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2022 Vol. 52, No. 7
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2022, 52(7): 1-7.
doi: 10.13204/j.gyjzg21060807
Abstract:
At present, the surface of super high-rise complex is mostly in the form of large-area glass walls, which cannot effectively respond to the indoor's light and heat requirements and climatic conditions. Therefore, the paper analyzed the difference characteristics of super high-rise complexes' different functional spaces for the requirements of light and heat performance, established three types of space unit skin parameter models for offices, hotel rooms and apartments, and performed performance on the Rhino&Grasshopper and Ladybug&Honeybee simulation platforms. Then Octopus was applied to complete multi-objective optimization. The results of multi-objective optimization were simulaneously analyzed, the suitable skin parameters were found, and the skin parameters of each space unit were analyzed and summarized, which could provide parameter suggestions for the skin design of super high-rise complex, and echo the difference of light and heat performance requirements of indoor space of super high-rise complex.
At present, the surface of super high-rise complex is mostly in the form of large-area glass walls, which cannot effectively respond to the indoor's light and heat requirements and climatic conditions. Therefore, the paper analyzed the difference characteristics of super high-rise complexes' different functional spaces for the requirements of light and heat performance, established three types of space unit skin parameter models for offices, hotel rooms and apartments, and performed performance on the Rhino&Grasshopper and Ladybug&Honeybee simulation platforms. Then Octopus was applied to complete multi-objective optimization. The results of multi-objective optimization were simulaneously analyzed, the suitable skin parameters were found, and the skin parameters of each space unit were analyzed and summarized, which could provide parameter suggestions for the skin design of super high-rise complex, and echo the difference of light and heat performance requirements of indoor space of super high-rise complex.
2022, 52(7): 8-16.
doi: 10.13204/j.gyjzg21102305
Abstract:
Due to the intensive use of land, high-rise housing is the main form of housing in China in the future. Under the dual-carbon background of China's government's efforts to achieve "carbon neutrality" and "carbon peak", the study of its life-cycle carbon emission reduction is of great significance for China's energy conservation and reduction. Based on the future weather data of a typical weather year in 2050, the paper took high-rise residential buildings under different climatic conditions in China as the research object, the carbon emissions in the whole life cycle of buildings with different building types, window-to-wall ratios, photoelectric conversion of photovoltaic panel and other factors were analyzed. Using building energy consumption simulation software, combined with related building carbon emission calculation methods, the net carbon C, building materials Cm, operating carbon emissions Co, and photovoltaics of 210 combinations of high-rise residential buildings with 4 variables were caltulated. The carbon reduction Cp in the whole life cycle of correlation analysis of calculation results was conducted, as well as the quantification and analysis of the mechanism of regional and architectural design variables and low-carbon targets. Studies have shown that it is increasingly difficult for high-rise residential buildings to achieve carbon neutrality in cold regions, hot summer and warm winter regions, mild regions, severe cold regions, and hot summer and cold winter regions. In order to achieve China's carbon neutrality goal by 2060, carbon-neutral high-rise residential buildings should be recommended in cold regions. From the perspective of carbon neutrality, the future development trend of high-rise residential buildings in the country is 30-34-storey residences; 34-storey building with I-shaped and 2 terraces and 4 households, 33-storey building with 2 terraces and 3 households should be the recommended types of carbon-neutral and high-rise residences in the southern and northern regions, respectively; the use of solar photovoltaic panels and the improvement of photovoltaic panel photoelectric conversion rate are effective means to achieve carbon neutrality of high-rise residential buildings in cold regions represented by Beijing.
Due to the intensive use of land, high-rise housing is the main form of housing in China in the future. Under the dual-carbon background of China's government's efforts to achieve "carbon neutrality" and "carbon peak", the study of its life-cycle carbon emission reduction is of great significance for China's energy conservation and reduction. Based on the future weather data of a typical weather year in 2050, the paper took high-rise residential buildings under different climatic conditions in China as the research object, the carbon emissions in the whole life cycle of buildings with different building types, window-to-wall ratios, photoelectric conversion of photovoltaic panel and other factors were analyzed. Using building energy consumption simulation software, combined with related building carbon emission calculation methods, the net carbon C, building materials Cm, operating carbon emissions Co, and photovoltaics of 210 combinations of high-rise residential buildings with 4 variables were caltulated. The carbon reduction Cp in the whole life cycle of correlation analysis of calculation results was conducted, as well as the quantification and analysis of the mechanism of regional and architectural design variables and low-carbon targets. Studies have shown that it is increasingly difficult for high-rise residential buildings to achieve carbon neutrality in cold regions, hot summer and warm winter regions, mild regions, severe cold regions, and hot summer and cold winter regions. In order to achieve China's carbon neutrality goal by 2060, carbon-neutral high-rise residential buildings should be recommended in cold regions. From the perspective of carbon neutrality, the future development trend of high-rise residential buildings in the country is 30-34-storey residences; 34-storey building with I-shaped and 2 terraces and 4 households, 33-storey building with 2 terraces and 3 households should be the recommended types of carbon-neutral and high-rise residences in the southern and northern regions, respectively; the use of solar photovoltaic panels and the improvement of photovoltaic panel photoelectric conversion rate are effective means to achieve carbon neutrality of high-rise residential buildings in cold regions represented by Beijing.
2022, 52(7): 17-26.
doi: 10.13204/j.gyjzg20122320
Abstract:
The research proposd a climate responsive design strategy for low- and middle-rise residential buildings in typical Chinese cities, in order to establish a multi-variable, multi-objective correlation parameter analysis framework based on the climate characteristics of typical cities in different climate zones. Through the residential building form parameters, such as the length-to-width ratio, the body shape coefficient, the community floor area ratio and other parameters, base on the meteorological parameters of five typical cities in China, with the objectives of lighting environment comfort and building energy demand, the study aimed to search for the optimal building form parameters in each city, and use multi-objective optimization as a pre-analytical method for building energy efficiency, to summarize the design rules of low and middle-rise residential buildings in Chinese typical cities.
The research proposd a climate responsive design strategy for low- and middle-rise residential buildings in typical Chinese cities, in order to establish a multi-variable, multi-objective correlation parameter analysis framework based on the climate characteristics of typical cities in different climate zones. Through the residential building form parameters, such as the length-to-width ratio, the body shape coefficient, the community floor area ratio and other parameters, base on the meteorological parameters of five typical cities in China, with the objectives of lighting environment comfort and building energy demand, the study aimed to search for the optimal building form parameters in each city, and use multi-objective optimization as a pre-analytical method for building energy efficiency, to summarize the design rules of low and middle-rise residential buildings in Chinese typical cities.
2022, 52(7): 27-31,232.
doi: 10.13204/j.gyjzg21040504
Abstract:
In order to construct the performance-based design method used by architects in the initial stage of design, the design strategy of building thermal performance with the calculation method of solar heating efficiency was explored. Taking the building height-to-width ratio, height-to-length ratio, and south-facing window-to-wall ratio as the building shape elements, the building solar heating potential function based on the building shape elements was obtained through orthogonal experiments, dynamic energy consumption simulation, and mathematical statistical analysis. After graphing the function, it was found that increasing the aspect ratio and the south-facing window-to-wall ratio could increase the solar heating potential of buildings. For the convenience of designers, a BIM-based building solar heating potential analysis software was developed and applied to actual projects. This research explored the performance-based analysis method at the preliminary stage of building design, provided designers with a collaborative analysis method for design strategy flexibility and energy consumption intensity change law, and improved the construction of a green performance-based design system for buildings.
In order to construct the performance-based design method used by architects in the initial stage of design, the design strategy of building thermal performance with the calculation method of solar heating efficiency was explored. Taking the building height-to-width ratio, height-to-length ratio, and south-facing window-to-wall ratio as the building shape elements, the building solar heating potential function based on the building shape elements was obtained through orthogonal experiments, dynamic energy consumption simulation, and mathematical statistical analysis. After graphing the function, it was found that increasing the aspect ratio and the south-facing window-to-wall ratio could increase the solar heating potential of buildings. For the convenience of designers, a BIM-based building solar heating potential analysis software was developed and applied to actual projects. This research explored the performance-based analysis method at the preliminary stage of building design, provided designers with a collaborative analysis method for design strategy flexibility and energy consumption intensity change law, and improved the construction of a green performance-based design system for buildings.
2022, 52(7): 32-39.
doi: 10.13204/j.gyjzg21091408
Abstract:
As the center of county economic and social development, it is of great significance to promote urban and rural green development and achieve the goal of carbon emission reduction. However, the county lacks the evaluation index system of green and low-carbon construction level at block scale. Based on the analysis of current research on big cities and the particularity of county towns, the paper selected four typical block types:residential, commercial, industrial and mixed, and constructed an evaluation index system of low-carbon construction level in the county block scale from five aspects:space, traffic, efficiency, facilities and greening. Finally, taking the area on the south bank of Pihe River in Jintang County as an example, this evaluation system was applied to evaluate the selected blocks, identify the weak links of carbon control in blocks, and put forward guidelines for low-carbon construction, which could provide important feedback and correction basis for low-carbon planning and construction in county towns.
As the center of county economic and social development, it is of great significance to promote urban and rural green development and achieve the goal of carbon emission reduction. However, the county lacks the evaluation index system of green and low-carbon construction level at block scale. Based on the analysis of current research on big cities and the particularity of county towns, the paper selected four typical block types:residential, commercial, industrial and mixed, and constructed an evaluation index system of low-carbon construction level in the county block scale from five aspects:space, traffic, efficiency, facilities and greening. Finally, taking the area on the south bank of Pihe River in Jintang County as an example, this evaluation system was applied to evaluate the selected blocks, identify the weak links of carbon control in blocks, and put forward guidelines for low-carbon construction, which could provide important feedback and correction basis for low-carbon planning and construction in county towns.
2022, 52(7): 40-47.
doi: 10.13204/j.gyjzg21090901
Abstract:
School-run factories appear at a special stage of development in our country and are facing transformation. The physical environment is an important dimension for evaluating the transformation of existing buildings. Taking the thermal environment as the starting point, field surveys were conducted on the regeneration space of the school-run factory. The indoor thermal environment in winter was objectively presented, and its influencing factors and mechanism were revealed preliminarily. The experimental results showed that:1) under non-extreme climatic conditions in winter, the indoor air temperature was 7.0-10.0℃, the relative humidity was 40.0%-60.0%, and there was no obvious heat stratification in indoor space, and feeling cold was mainly due to low air temperature; 2) the moderately renovated envelope structure met the needs of space use and distinctive features, but had a limited role in regulating the indoor thermal environment, and there was a 0.5-1.0 h lag time for outdoor temperature and humidity fluctuations; 3) the foyer space effectively buffered outdoor temperature and humidity fluctuations and reduced heat loss in winter. Evaluation of the school-run factory renovation from environmental results could provide new thinking dimensions for the renovation design of similar existing buildings.
School-run factories appear at a special stage of development in our country and are facing transformation. The physical environment is an important dimension for evaluating the transformation of existing buildings. Taking the thermal environment as the starting point, field surveys were conducted on the regeneration space of the school-run factory. The indoor thermal environment in winter was objectively presented, and its influencing factors and mechanism were revealed preliminarily. The experimental results showed that:1) under non-extreme climatic conditions in winter, the indoor air temperature was 7.0-10.0℃, the relative humidity was 40.0%-60.0%, and there was no obvious heat stratification in indoor space, and feeling cold was mainly due to low air temperature; 2) the moderately renovated envelope structure met the needs of space use and distinctive features, but had a limited role in regulating the indoor thermal environment, and there was a 0.5-1.0 h lag time for outdoor temperature and humidity fluctuations; 3) the foyer space effectively buffered outdoor temperature and humidity fluctuations and reduced heat loss in winter. Evaluation of the school-run factory renovation from environmental results could provide new thinking dimensions for the renovation design of similar existing buildings.
2022, 52(7): 48-54.
doi: 10.13204/j.gyjzg21062414
Abstract:
In urban renewal, many old industrial plants have not been fully utilized. Most of them still adopt the method of "demolition and large-scale construction, overturning and restarting". Combining old industrial plants with green ecological transformation technology is a very urgent problem that needs to be solved in the renewal and transformation of old industrial plants in our country. It is also the only way to practice the concept of adhering to the harmonious coexistence of human and nature. It is very important to carry out research on the green transformation of old industrial factories. Taking COOMO Furnishings Ltd. transformation project as an example, the described technical points of the old industrial plant green ecological reconstruction and expansion. The space layout was optimized for the original layout, according to the original layout of the addition of earth-covered buildings and L-shaped buildings to ensure the expansion of the used space, while optimizing the site zoning, traffic layout and green space configuration; in terms of the integration of old and new buildings, the concept of "mountain building" was implemented to create a good working environment, and modern concepts were introduced to update the façade of existing industrial buildings, so that the old and new buildings could be integrated; in the field of green ecological practice, the building would be hidden into green vegetation, the planting roofs or photovoltaic power generation, wind utilization and other measures would be introduced to achieve energy conservation and environmental protection.
In urban renewal, many old industrial plants have not been fully utilized. Most of them still adopt the method of "demolition and large-scale construction, overturning and restarting". Combining old industrial plants with green ecological transformation technology is a very urgent problem that needs to be solved in the renewal and transformation of old industrial plants in our country. It is also the only way to practice the concept of adhering to the harmonious coexistence of human and nature. It is very important to carry out research on the green transformation of old industrial factories. Taking COOMO Furnishings Ltd. transformation project as an example, the described technical points of the old industrial plant green ecological reconstruction and expansion. The space layout was optimized for the original layout, according to the original layout of the addition of earth-covered buildings and L-shaped buildings to ensure the expansion of the used space, while optimizing the site zoning, traffic layout and green space configuration; in terms of the integration of old and new buildings, the concept of "mountain building" was implemented to create a good working environment, and modern concepts were introduced to update the façade of existing industrial buildings, so that the old and new buildings could be integrated; in the field of green ecological practice, the building would be hidden into green vegetation, the planting roofs or photovoltaic power generation, wind utilization and other measures would be introduced to achieve energy conservation and environmental protection.
2022, 52(7): 55-65.
doi: 10.13204/j.gyjzg21020208
Abstract:
The guiding design of railway passenger station interior is the key factor that affects passenger transfer efficiency and traffic experience. It needs more intuitionistic method and more objective data to evaluate and quantify. Taking the space-oriented function and passenger transfer efficiency as the evaluation factors of space-oriented, and the EPB research mode of railway passenger station transfer as the framework, virtual reality technology and space syntax were used to set up the multi-group transfer route-finding experiment, based on the subjective evaluation index of the volunteer questionnaire, the linear efficiency of the volunteer transfer and the waiting time of the volunteer transfer, which were accurately collected by the Unity trajectory recording system, were taken as the objective evaluation indexes, the oriented evaluation model was proposed. The applicability of the proposed guidance evaluation model in the case study was verified by taking the space of the arrival floor of Wuhan Station as the object of study, in order to provide new research ideas and means for the guidance study of traffic buildings.
The guiding design of railway passenger station interior is the key factor that affects passenger transfer efficiency and traffic experience. It needs more intuitionistic method and more objective data to evaluate and quantify. Taking the space-oriented function and passenger transfer efficiency as the evaluation factors of space-oriented, and the EPB research mode of railway passenger station transfer as the framework, virtual reality technology and space syntax were used to set up the multi-group transfer route-finding experiment, based on the subjective evaluation index of the volunteer questionnaire, the linear efficiency of the volunteer transfer and the waiting time of the volunteer transfer, which were accurately collected by the Unity trajectory recording system, were taken as the objective evaluation indexes, the oriented evaluation model was proposed. The applicability of the proposed guidance evaluation model in the case study was verified by taking the space of the arrival floor of Wuhan Station as the object of study, in order to provide new research ideas and means for the guidance study of traffic buildings.
2022, 52(7): 66-71.
doi: 10.13204/j.gyjzG21021904
Abstract:
The necessity and urgency of transforming the industrial buildings in city center into nursing homes were analyzed. The combined strategies of the technology skill and art culture were studied and analyzed from the aspects of structure reconstruction, updated function, updated interface, environmental improvement, humanistic care, humanity and intelligent, the historical and cultural elements were also taken into account, the reconstruction of No.2 Towel Factory of Shanghai into a nursing home was taken as an example. The research could provide effective methods and measures to solve the reconstruction problems of industrial buildings in urban renewl.
The necessity and urgency of transforming the industrial buildings in city center into nursing homes were analyzed. The combined strategies of the technology skill and art culture were studied and analyzed from the aspects of structure reconstruction, updated function, updated interface, environmental improvement, humanistic care, humanity and intelligent, the historical and cultural elements were also taken into account, the reconstruction of No.2 Towel Factory of Shanghai into a nursing home was taken as an example. The research could provide effective methods and measures to solve the reconstruction problems of industrial buildings in urban renewl.
2022, 52(7): 72-78.
doi: 10.13204/j.gyjzg21070909
Abstract:
The horizontal relative slip of the precast shear wall joints has a negative impact on the seismic performance of the precast shear wall.In order to improve the mechanical properties of the precast shear wall joints, a new type of precast shear wall with large-size reinforced tenon to resist the shear force of the joints and the longitudinal connecting steel bars to bear tensile and compressive stress and yield energy dissipation was proposed.In order to investigate the seismic performance of reinforced tenon precast low-rise shear walls, two reinforced tenon precast low-rise shear walls with aspect ratio of 1.76 and 1.5 were tested under quasi-static loading.The crack development law and failure mode of the specimens were observed, and the hysteresis curve, skeleton curve, bearing capacity, stiffness degradation, ductility, energy dissipation capacity, steel bar strain and joint connection performance were analyzed.The results showed that the failure modes of the two specimens were compressive bending failure at the bottom joint of the wall, but there was no large shear slip at the joint interface, which showed a good shear bearing capacity.The mechanical properties such as initial stiffness, energy dissipation capacity and ductility of the wall could reach the level of ‘equivalent cast-in-situ’.At the same time, the specimens with lower aspect ratio showed better seismic performance.
The horizontal relative slip of the precast shear wall joints has a negative impact on the seismic performance of the precast shear wall.In order to improve the mechanical properties of the precast shear wall joints, a new type of precast shear wall with large-size reinforced tenon to resist the shear force of the joints and the longitudinal connecting steel bars to bear tensile and compressive stress and yield energy dissipation was proposed.In order to investigate the seismic performance of reinforced tenon precast low-rise shear walls, two reinforced tenon precast low-rise shear walls with aspect ratio of 1.76 and 1.5 were tested under quasi-static loading.The crack development law and failure mode of the specimens were observed, and the hysteresis curve, skeleton curve, bearing capacity, stiffness degradation, ductility, energy dissipation capacity, steel bar strain and joint connection performance were analyzed.The results showed that the failure modes of the two specimens were compressive bending failure at the bottom joint of the wall, but there was no large shear slip at the joint interface, which showed a good shear bearing capacity.The mechanical properties such as initial stiffness, energy dissipation capacity and ductility of the wall could reach the level of ‘equivalent cast-in-situ’.At the same time, the specimens with lower aspect ratio showed better seismic performance.
2022, 52(7): 79-85.
doi: 10.13204/j.gyjzG22041708
Abstract:
The static loading test was carried out on six full-scale steel-concrete composite girders with stud-epoxy mortar hybrid connectors. The effect of the spacing between stud groups on the mechanical properties of composite girders was considered. The bearing capacity and the interface slip characteristics, as well as the shear force distribution sequence and the strain evolution of the bolts were analyzed and summarized. The results indicated that the epoxy mortar bonding layer bore the main shear force in the elastic stage. After entering the elastic-plastic stage, the stud began to bear the main shear force; in the failure stage, the interface sliding shift between the precast concrete and the steel beam should not exceed 2 mm at the loading point and middle position of the composite girders, indicating that there was a good cooperative work between the precast concrete slab and the steel beam. The residual flexural bearing capacity of composite girder was still more than 60%, which indicated that it had good ductility.When the spacing between the stud groups was reduced from 700 mm to 525 mm and 525 mm to 420 mm, the ultimate bearing capacity and the total energy consumption increased by 3.4% and 41.9%, 4.1% and 2.5%, respectively. Finally, based on the plastic theory, a formula for calculating the flexural bearing capacity of steel-concrete composite beams with hybrid connections was proposed.
The static loading test was carried out on six full-scale steel-concrete composite girders with stud-epoxy mortar hybrid connectors. The effect of the spacing between stud groups on the mechanical properties of composite girders was considered. The bearing capacity and the interface slip characteristics, as well as the shear force distribution sequence and the strain evolution of the bolts were analyzed and summarized. The results indicated that the epoxy mortar bonding layer bore the main shear force in the elastic stage. After entering the elastic-plastic stage, the stud began to bear the main shear force; in the failure stage, the interface sliding shift between the precast concrete and the steel beam should not exceed 2 mm at the loading point and middle position of the composite girders, indicating that there was a good cooperative work between the precast concrete slab and the steel beam. The residual flexural bearing capacity of composite girder was still more than 60%, which indicated that it had good ductility.When the spacing between the stud groups was reduced from 700 mm to 525 mm and 525 mm to 420 mm, the ultimate bearing capacity and the total energy consumption increased by 3.4% and 41.9%, 4.1% and 2.5%, respectively. Finally, based on the plastic theory, a formula for calculating the flexural bearing capacity of steel-concrete composite beams with hybrid connections was proposed.
2022, 52(7): 86-92,65.
doi: 10.13204/j.gyjzG21042714
Abstract:
Diamond grid braced frames structure(DBF) is a new type of lateral force support structure, which can be used in multi-high-rise steel structure housing to facilitate the installation of enclosure wall.In order to verify the seismic performance of diamond grid brace, the finite element quasi-static analysis of single-span two-story diamond grid braced structure was carried out, and compared with the traditional single diagonal bar brace, herring-bone brace and cross brace under the same steel consumption.The results showed that the diamond grid braced was not prone to buckling failure, and the structure had good ductility and stiffness without increasing the amount of steel.The diamond grid braced structure had adverse effects on the frame, especially on the side columns. Therefore, according to the basic assumptions of structural mechanics, considering the adverse effects of the diamond grid braced structure on the side columns, a design method for diamond grid braced structure was proposed, which could be used as a reference for practical engineering.
Diamond grid braced frames structure(DBF) is a new type of lateral force support structure, which can be used in multi-high-rise steel structure housing to facilitate the installation of enclosure wall.In order to verify the seismic performance of diamond grid brace, the finite element quasi-static analysis of single-span two-story diamond grid braced structure was carried out, and compared with the traditional single diagonal bar brace, herring-bone brace and cross brace under the same steel consumption.The results showed that the diamond grid braced was not prone to buckling failure, and the structure had good ductility and stiffness without increasing the amount of steel.The diamond grid braced structure had adverse effects on the frame, especially on the side columns. Therefore, according to the basic assumptions of structural mechanics, considering the adverse effects of the diamond grid braced structure on the side columns, a design method for diamond grid braced structure was proposed, which could be used as a reference for practical engineering.
2022, 52(7): 93-97.
doi: 10.13204/j.gyjzg20042008
Abstract:
In order to study the influence of fire local high temperature on the Pushover analysis of high-rise building structures, the steel-concrete composite structure was taken as the research object, the lateral load was considered in the form of uniform distribution, and the numerical model was established by using ABAQUS finite element software to analyze the structural elastic-plastic response and compare the effects of different temperature effects on the analysis results. The results showed that with the increase of the local high temperature, the relative errors of the top displacement and interlayer displacement of the structure were gradually increasing, and the local high temperature had a significant effect on the Pushover analysis results of the structure. The research results could provide a reference for reducing the damage to the structure caused by the simultaneous action of local high temperature and lateral load.
In order to study the influence of fire local high temperature on the Pushover analysis of high-rise building structures, the steel-concrete composite structure was taken as the research object, the lateral load was considered in the form of uniform distribution, and the numerical model was established by using ABAQUS finite element software to analyze the structural elastic-plastic response and compare the effects of different temperature effects on the analysis results. The results showed that with the increase of the local high temperature, the relative errors of the top displacement and interlayer displacement of the structure were gradually increasing, and the local high temperature had a significant effect on the Pushover analysis results of the structure. The research results could provide a reference for reducing the damage to the structure caused by the simultaneous action of local high temperature and lateral load.
2022, 52(7): 98-105,97.
doi: 10.13204/j.gyjzG22050303
Abstract:
There are few researches on stainless steel high strength bolts worldwide, and there is a lack of uniform standards for bolt product specifications. In order to study the mechanical properties and tightening methods of stainless steel high strength bolts, physical tensile tests, hardness tests and tightening tests were carried out on two kinds of 10.9 grade stainless steel high-strength bolts. The tensile strength and hardness were obtained. The preload and tightening process were determined. The results showed that the two kinds of stainless steel high-strength bolts met the requirements of mechanical properties of grade 10.9 high-strength bolts. The thread galling of stainless steel bolts occurred during the tightening process. The lubricant Molykote D-321R had the best friction reduction effect on the galling and could reduce the torque coefficient of stainless steel high-strength bolts to the limit of torque coefficients of the high-strength bolts for steel structures. For the two methods of applying bolt preload, the torque method and the rotation angle method, the bolt preload obtained by the torque method was more consistent. The requirements for the construction preload of stainless steel high-strength bolts were proposed, and the construction torque was given to provide a reference for engineering application.
There are few researches on stainless steel high strength bolts worldwide, and there is a lack of uniform standards for bolt product specifications. In order to study the mechanical properties and tightening methods of stainless steel high strength bolts, physical tensile tests, hardness tests and tightening tests were carried out on two kinds of 10.9 grade stainless steel high-strength bolts. The tensile strength and hardness were obtained. The preload and tightening process were determined. The results showed that the two kinds of stainless steel high-strength bolts met the requirements of mechanical properties of grade 10.9 high-strength bolts. The thread galling of stainless steel bolts occurred during the tightening process. The lubricant Molykote D-321R had the best friction reduction effect on the galling and could reduce the torque coefficient of stainless steel high-strength bolts to the limit of torque coefficients of the high-strength bolts for steel structures. For the two methods of applying bolt preload, the torque method and the rotation angle method, the bolt preload obtained by the torque method was more consistent. The requirements for the construction preload of stainless steel high-strength bolts were proposed, and the construction torque was given to provide a reference for engineering application.
2022, 52(7): 106-112,71.
doi: 10.13204/j.gyjzG22010612
Abstract:
The compressive strength of grout after high temperature was studied, and the formula for calculating the compressive strength of grout after being subjected to high temperature was derived. In order to study the mechanical properties of semi-grouting sleeve connection after of high temperature, the pull-out test of semi-grouting sleeve connection after being subjected to high temperature was designed with temperature, anchorage length and protective layer thickness as variables. The test results showed that the failure mode of specimens changed with the increase of temperature, and the failure mode changed gradually from steel bar fracture failure to steel bar pull-out failure. Increasing anchorage length could effectively improve the mechanical properties of semi-grouting sleeve connections. At 600℃, the ultimate load and ultimate displacement losses of specimens with anchor length of 120 mm were 6% and 46% respectively, which were far smaller than those of specimens with anchor length of 100 mm. The existence of protective layer was beneficial to improve the bearing capacity and ductility of semi-grouting sleeve connections. Based on the test results, the bearing capacity formula of semi-grouting sleeve connection after being subjected to high temperature was deduced, and the predicted values were in good agreement with the test values.
The compressive strength of grout after high temperature was studied, and the formula for calculating the compressive strength of grout after being subjected to high temperature was derived. In order to study the mechanical properties of semi-grouting sleeve connection after of high temperature, the pull-out test of semi-grouting sleeve connection after being subjected to high temperature was designed with temperature, anchorage length and protective layer thickness as variables. The test results showed that the failure mode of specimens changed with the increase of temperature, and the failure mode changed gradually from steel bar fracture failure to steel bar pull-out failure. Increasing anchorage length could effectively improve the mechanical properties of semi-grouting sleeve connections. At 600℃, the ultimate load and ultimate displacement losses of specimens with anchor length of 120 mm were 6% and 46% respectively, which were far smaller than those of specimens with anchor length of 100 mm. The existence of protective layer was beneficial to improve the bearing capacity and ductility of semi-grouting sleeve connections. Based on the test results, the bearing capacity formula of semi-grouting sleeve connection after being subjected to high temperature was deduced, and the predicted values were in good agreement with the test values.
2022, 52(7): 113-118.
doi: 10.13204/j.gyjzG21121307
Abstract:
In order to explore the evolution law of acoustic emission in the process of bending damage of timber with different service life, three groups of wood with different service life were prepared for three-point bending acoustic emission test. The paper studied the correlation between the bearing process of timber with the characteristics of acoustic emission parameters, and deeply analyzed the evolution of acoustic emission dominant frequency and energy characteristics precursors before timber instability and failure. The test results showed that the service life of timber affected the acoustic emission activity, and the change of acoustic emission parameters could reflect the internal damage of timber, so as to indirectly reflect the service state of timber; the service life affected the main frequency distribution to a certain extent. The main frequency was mainly distributed in 0-200 kHz, which was obviously distributed in segments. The main frequency distribution of timber with long service life was relatively discrete; the change of energy in each frequency band of each group of specimens in the damage process corresponded to different specimen states. When the proportion of medium and low frequency band was relatively high, it was mainly elastic deformation, and when the proportion of high frequency band was relatively high, it indicated the fracture of specimens, which had a certain value for predicting timber fracture.
In order to explore the evolution law of acoustic emission in the process of bending damage of timber with different service life, three groups of wood with different service life were prepared for three-point bending acoustic emission test. The paper studied the correlation between the bearing process of timber with the characteristics of acoustic emission parameters, and deeply analyzed the evolution of acoustic emission dominant frequency and energy characteristics precursors before timber instability and failure. The test results showed that the service life of timber affected the acoustic emission activity, and the change of acoustic emission parameters could reflect the internal damage of timber, so as to indirectly reflect the service state of timber; the service life affected the main frequency distribution to a certain extent. The main frequency was mainly distributed in 0-200 kHz, which was obviously distributed in segments. The main frequency distribution of timber with long service life was relatively discrete; the change of energy in each frequency band of each group of specimens in the damage process corresponded to different specimen states. When the proportion of medium and low frequency band was relatively high, it was mainly elastic deformation, and when the proportion of high frequency band was relatively high, it indicated the fracture of specimens, which had a certain value for predicting timber fracture.
2022, 52(7): 119-122,150.
doi: 10.13204/j.gyjzg21070805
Abstract:
By using the medium-sized triaxial apparatus, the miscellaneous fill in the dump of the Jishan mining area in Nanjing was studied. Through the confining pressure tests of 100 kPa, 200 kPa and 400 kPa for miscellaneous fillings of silty clay, sand and silt with the stone content of 30%, the influence of matrixs on the mechanical properties of miscellaneous fillings was analyzed. The results showed that the (σ1-σ3)-ε1 curves of miscellaneous fillings were hyperbolic and displayed a strain hardening tendency. Under the same confining pressure, when the confining pressure was low, with the change of the matrixs, the differences for deviation stress of miscellaneous fillings were very similar. When the confining pressure was high, with the change of the matrixs, the differences of deviation stress of miscellaneous fillings were significant. For the same matrix, with the increase of confining pressure, the deviation stress differences of miscellaneous fillings increased gradually, and the increase of deviation stress differences for miscellaneous fillings of silt was the largest. For the miscellaneous fillings of silty clay and silt, the volume was always in shear shrinkage. With the increase of axial strain, changes for the volume strain of miscellaneous fillings of sand were more complex. When the confining pressure was 100 kPa, the miscellaneous fillings of sand showed a shear shrinkage tendency first, and then dilatancy. When the confining pressure was 200 kPa and 400 kPa, sand was always in shear shrinkage. Based on comprehensive comparisons of strength parameters and constitutive model parameters, it indicated that the matrix was an important factor influencing the mechanical parameters of miscellaneous fillings.
By using the medium-sized triaxial apparatus, the miscellaneous fill in the dump of the Jishan mining area in Nanjing was studied. Through the confining pressure tests of 100 kPa, 200 kPa and 400 kPa for miscellaneous fillings of silty clay, sand and silt with the stone content of 30%, the influence of matrixs on the mechanical properties of miscellaneous fillings was analyzed. The results showed that the (σ1-σ3)-ε1 curves of miscellaneous fillings were hyperbolic and displayed a strain hardening tendency. Under the same confining pressure, when the confining pressure was low, with the change of the matrixs, the differences for deviation stress of miscellaneous fillings were very similar. When the confining pressure was high, with the change of the matrixs, the differences of deviation stress of miscellaneous fillings were significant. For the same matrix, with the increase of confining pressure, the deviation stress differences of miscellaneous fillings increased gradually, and the increase of deviation stress differences for miscellaneous fillings of silt was the largest. For the miscellaneous fillings of silty clay and silt, the volume was always in shear shrinkage. With the increase of axial strain, changes for the volume strain of miscellaneous fillings of sand were more complex. When the confining pressure was 100 kPa, the miscellaneous fillings of sand showed a shear shrinkage tendency first, and then dilatancy. When the confining pressure was 200 kPa and 400 kPa, sand was always in shear shrinkage. Based on comprehensive comparisons of strength parameters and constitutive model parameters, it indicated that the matrix was an important factor influencing the mechanical parameters of miscellaneous fillings.
2022, 52(7): 123-127.
doi: 10.13204/j.gyjzg21061304
Abstract:
The stress of soil particles in seepage pore channels of sand in penetration processes was analyzed. Based on the criterion for the probability of particles across filter clothes, comprehensively considering the influence of pore sizes for filter clothes in inverted layers and filter wire diameters, hydraulic slopes, grain size distribution, densities and angles of internal friction on the seepage loss of soil particles, the equation for soil particle seepage loss of sand soil based on the probability was established. The radial permeability tests of sandy soil from Yongding River in Beijing were conducted in the conditions of different pore sizes for filter clothes, and the loss of soil particles in tests were collected. The test results were compared with the calculated results by the seepage loss equation of soil particles, and the two were consistent. It could be regarded that the size of filter clothes was positively correlated with the radial permeability coefficient of sandy soil and the soil particle loss. The established seepage loss equation of soil particles based on the probability could be better calculated the seepage loss of sandy soil particles in the condition for the seepage boundary of filters.
The stress of soil particles in seepage pore channels of sand in penetration processes was analyzed. Based on the criterion for the probability of particles across filter clothes, comprehensively considering the influence of pore sizes for filter clothes in inverted layers and filter wire diameters, hydraulic slopes, grain size distribution, densities and angles of internal friction on the seepage loss of soil particles, the equation for soil particle seepage loss of sand soil based on the probability was established. The radial permeability tests of sandy soil from Yongding River in Beijing were conducted in the conditions of different pore sizes for filter clothes, and the loss of soil particles in tests were collected. The test results were compared with the calculated results by the seepage loss equation of soil particles, and the two were consistent. It could be regarded that the size of filter clothes was positively correlated with the radial permeability coefficient of sandy soil and the soil particle loss. The established seepage loss equation of soil particles based on the probability could be better calculated the seepage loss of sandy soil particles in the condition for the seepage boundary of filters.
2022, 52(7): 128-136,118.
doi: 10.13204/j.gyjzg21070206
Abstract:
To revealing the reasons for shallow landslides of expansive soil slopes, in reference to the existing calculation ways of multifield-coupling numerical analysis, the seepage processes from unsaturation to saturation in expansive soil slopes and hygroscopic expansion processes were simulated by the two-phase flow module and thermal module of the finite difference software FLAC2D;based on the transformation relations for saturation degrees, temperatures and thermal expansion coefficients of expansive soil and integrating and extracting the information from both of the modules simultaneously, the hygroscopic expansion effect of expansive soil was simulated in time;the three fields involving the seepage field, displacement field and stress field were coupled under consideration for the changes of groundwater levels and permeability coefficients and intensity attenuation. And then, the numerical model with or without expansive deformation was constructed. The seepage processes from unsaturation to saturation in slopes considered and not considered the hygroscopic expansion during rainfall and the stability of slopes were simulated individually;the difference of seepage fields and slopes stability between considering and not considering the hygroscopic expansion effect in the same rainfall intensities but different rainfall duration was contrasted and analyzed. The important reason caused shallow landslides of expansive soil slopes was revealed, it was hygroscopic expansion of expansive soil. Furthermore, the stability of expansive soil slopes under different rainfall intensities and durations was further studied, the variation and distribution of the seepage field and stress field in slopes were compared and analyzed at the same time, and the effects of different rainfall conditions on shallow landslides were obtained.
To revealing the reasons for shallow landslides of expansive soil slopes, in reference to the existing calculation ways of multifield-coupling numerical analysis, the seepage processes from unsaturation to saturation in expansive soil slopes and hygroscopic expansion processes were simulated by the two-phase flow module and thermal module of the finite difference software FLAC2D;based on the transformation relations for saturation degrees, temperatures and thermal expansion coefficients of expansive soil and integrating and extracting the information from both of the modules simultaneously, the hygroscopic expansion effect of expansive soil was simulated in time;the three fields involving the seepage field, displacement field and stress field were coupled under consideration for the changes of groundwater levels and permeability coefficients and intensity attenuation. And then, the numerical model with or without expansive deformation was constructed. The seepage processes from unsaturation to saturation in slopes considered and not considered the hygroscopic expansion during rainfall and the stability of slopes were simulated individually;the difference of seepage fields and slopes stability between considering and not considering the hygroscopic expansion effect in the same rainfall intensities but different rainfall duration was contrasted and analyzed. The important reason caused shallow landslides of expansive soil slopes was revealed, it was hygroscopic expansion of expansive soil. Furthermore, the stability of expansive soil slopes under different rainfall intensities and durations was further studied, the variation and distribution of the seepage field and stress field in slopes were compared and analyzed at the same time, and the effects of different rainfall conditions on shallow landslides were obtained.
2022, 52(7): 137-144,214.
doi: 10.13204/j.gyjzg2022050907
Abstract:
In the petrochemical industry, heavy crawler cranes are often used for lifting of large equipment. In order to meet the requirements of the foundation bearing capacity for the crane, the soil replaced cushion is often employed to treat the ground and then steel tie plates are laid on the cushion underneath the crane. The composition of that soil and foundation system and consequently its bearing characteristics, are obviously different from that of buildings. Combined with a practical project of hoisting foundation treatment, the bearing characteristics of that kind of foundation system were studied through numerical simulations. Firstly, through the calculation and field measurement analysis under the actual hoisting loads, the deformation and load transfer characteristics of that kind of foundation system under the working loads were revealed, and the feasibility of the proposed elastoplastic finite element model was verified. Then, the safety factor for the bearing capacity of that foundation system was studied through finite element calculations. Comparing with the simplified checking results by Technical Code for Ground Treatment of Buildings(JGJ 79-2012), it showed that the checking calculation of that kind of foundation by the code was too conservative. It was also discussed whether the tie plates under the crane were connected, whether just one raw of the steel tie plates could be taken for the bearing capacity calculation, whether it could be calculated by a two-dimensional model. All of the above research results could provide reference to the development of simplified checking methods.
In the petrochemical industry, heavy crawler cranes are often used for lifting of large equipment. In order to meet the requirements of the foundation bearing capacity for the crane, the soil replaced cushion is often employed to treat the ground and then steel tie plates are laid on the cushion underneath the crane. The composition of that soil and foundation system and consequently its bearing characteristics, are obviously different from that of buildings. Combined with a practical project of hoisting foundation treatment, the bearing characteristics of that kind of foundation system were studied through numerical simulations. Firstly, through the calculation and field measurement analysis under the actual hoisting loads, the deformation and load transfer characteristics of that kind of foundation system under the working loads were revealed, and the feasibility of the proposed elastoplastic finite element model was verified. Then, the safety factor for the bearing capacity of that foundation system was studied through finite element calculations. Comparing with the simplified checking results by Technical Code for Ground Treatment of Buildings(JGJ 79-2012), it showed that the checking calculation of that kind of foundation by the code was too conservative. It was also discussed whether the tie plates under the crane were connected, whether just one raw of the steel tie plates could be taken for the bearing capacity calculation, whether it could be calculated by a two-dimensional model. All of the above research results could provide reference to the development of simplified checking methods.
2022, 52(7): 145-150.
doi: 10.13204/j.gyjzG21071406
Abstract:
In the engineering design of modal analysis for the foundation of Centrifugal Hypergravity and Interdisciplinary Experiment Facility (CHIEF) to obtain structural dynamic characteristics, as the equipment foundation is deeply embedded, the restraint effect of side soil on the structure must be fully considered. According to the properties of different layers of soil, the linear spring element was used to simulate the boundary conditions of each contact surface between foundation and soil, and five different bases such as lateral loading test were used to take the value of spring stiffness. The calculation results of the five groups of models were similar, and the discrete deviation of the results was small, which led to more reliable modal analysis results. Further, the sensitivity analysis of the stiffness of the boundary spring on the side of the foundation structure was carried out, and the tangential constraint of soil on the foundation structure was considered by the tangential spring. Through the numerical results, the influence of the side soil boundary on the natural frequency of each section of the hypergravity centrifuge foundation in the project was more comprehensively grasped, so as to guide the blueprint design and avoid invalid investment.
In the engineering design of modal analysis for the foundation of Centrifugal Hypergravity and Interdisciplinary Experiment Facility (CHIEF) to obtain structural dynamic characteristics, as the equipment foundation is deeply embedded, the restraint effect of side soil on the structure must be fully considered. According to the properties of different layers of soil, the linear spring element was used to simulate the boundary conditions of each contact surface between foundation and soil, and five different bases such as lateral loading test were used to take the value of spring stiffness. The calculation results of the five groups of models were similar, and the discrete deviation of the results was small, which led to more reliable modal analysis results. Further, the sensitivity analysis of the stiffness of the boundary spring on the side of the foundation structure was carried out, and the tangential constraint of soil on the foundation structure was considered by the tangential spring. Through the numerical results, the influence of the side soil boundary on the natural frequency of each section of the hypergravity centrifuge foundation in the project was more comprehensively grasped, so as to guide the blueprint design and avoid invalid investment.
2022, 52(7): 151-158.
doi: 10.13204/j.gyjzG20122608
Abstract:
The prediction of chloride diffusion in concrete is the key and difficult point of durability prediction of concrete in chloride environment. Nernst-Einstein equation was used to improve the general formula of GEM equation. Combined with test data, the chloride diffusion process equation of concrete with different void characteristics and different thicknesses of protective layer was derived. The influence of concrete curing age, mineral admixture and fiber content on the diffusion index n in the equation was analyzed. The life prediction model, with chloride ion concentration as the control target, predicted the critical porosity requirements of concrete under different concrete cover thicknesses with 100-year design life. When the minimum cover thickness was 6 cm, the concrete porosity should be controlled below 8%. The prediction results were basically reasonable. The prediction method could provide a reference for the optimal design of chloride corrosion durability of coastal concrete structures.
The prediction of chloride diffusion in concrete is the key and difficult point of durability prediction of concrete in chloride environment. Nernst-Einstein equation was used to improve the general formula of GEM equation. Combined with test data, the chloride diffusion process equation of concrete with different void characteristics and different thicknesses of protective layer was derived. The influence of concrete curing age, mineral admixture and fiber content on the diffusion index n in the equation was analyzed. The life prediction model, with chloride ion concentration as the control target, predicted the critical porosity requirements of concrete under different concrete cover thicknesses with 100-year design life. When the minimum cover thickness was 6 cm, the concrete porosity should be controlled below 8%. The prediction results were basically reasonable. The prediction method could provide a reference for the optimal design of chloride corrosion durability of coastal concrete structures.
2022, 52(7): 159-172,47.
doi: 10.13204/j.gyjzG21090801
Abstract:
Architectural design is a complex process, which not only needs knowledge and experience of architects but also their imagination and creativity. Artificial intelligence (AI) technology can digitize the architectural theory and design experience, improve the efficiency of the design process, and also provide more ideas for design. To solve different problems in architectural design, a variety of AI technologies have been applied and many methods have been proposed. Relevant achievements in the past five years were summarized and sorted out from the perspective of design problems, AI technologies and solutions. And the research status and development trends were analyzed. The summarization revealed distribution features of relevant researches in recent years. In the design task, the most popular issues were the layout and shape, which reached 42% and 26% of the reports respectively, and in AI technology, the most extensive application was optimization algorithms and neural networks, which accounted for 41% and 22% of the reports respectively. However, the application of AI in the field of architectural design has not formed a unified theoretical system yet, facing a crucial challenge of generality and standardization.
Architectural design is a complex process, which not only needs knowledge and experience of architects but also their imagination and creativity. Artificial intelligence (AI) technology can digitize the architectural theory and design experience, improve the efficiency of the design process, and also provide more ideas for design. To solve different problems in architectural design, a variety of AI technologies have been applied and many methods have been proposed. Relevant achievements in the past five years were summarized and sorted out from the perspective of design problems, AI technologies and solutions. And the research status and development trends were analyzed. The summarization revealed distribution features of relevant researches in recent years. In the design task, the most popular issues were the layout and shape, which reached 42% and 26% of the reports respectively, and in AI technology, the most extensive application was optimization algorithms and neural networks, which accounted for 41% and 22% of the reports respectively. However, the application of AI in the field of architectural design has not formed a unified theoretical system yet, facing a crucial challenge of generality and standardization.
2022, 52(7): 173-185.
doi: 10.13204/j.gyjzG20111808
Abstract:
Shrinkage reduction and crack prevention for concrete are the key problems in concrete durability research. There are many shrinkage combination control methods for modern concrete, which can be divided into three categories:internal admixtures combination, internal-external combination, and active-passive combination. From the perspectives of physics, chemistry, mechanics, and microcosmic, the synergistic mechanism and occurrence conditions of the three kinds of combined regulation were summarized. Several urgent problems in theoretical and experimental research were analyzed, and suggestions for future research were proposed. Through scientific matching design, the combined methods can realize timing and orientation, high efficiency, complementary advantages and mutual elimination of disadvantages, and are expected to provide a whole process and a much better adaptability technical solutions for shrinkage reduction and crack prevention of concrete.
Shrinkage reduction and crack prevention for concrete are the key problems in concrete durability research. There are many shrinkage combination control methods for modern concrete, which can be divided into three categories:internal admixtures combination, internal-external combination, and active-passive combination. From the perspectives of physics, chemistry, mechanics, and microcosmic, the synergistic mechanism and occurrence conditions of the three kinds of combined regulation were summarized. Several urgent problems in theoretical and experimental research were analyzed, and suggestions for future research were proposed. Through scientific matching design, the combined methods can realize timing and orientation, high efficiency, complementary advantages and mutual elimination of disadvantages, and are expected to provide a whole process and a much better adaptability technical solutions for shrinkage reduction and crack prevention of concrete.
2022, 52(7): 186-191,127.
doi: 10.13204/j.gyjzG20091001
Abstract:
Three-point bending fatigue test was carried out on basalt fiber reinforced concrete specimens with four kinds of fiber contents under three stress levels. Mathematical statistics was used to test the Weibull distribution of the bending fatigue life on the fatigue test data, and fitting the double logarithmic fatigue equation under different failure probabilities. The results showed that the bending fatigue life of basalt fiber reinforced concrete conformed to the two-parameter Weibull distribution, as the stress level decreased, the Weibull shape parameter first decreased and then increased, the dispersion of bending fatigue life first increased and then decreased; with the increase of fiber content, the distribution of bending fatigue life was more uniform, the dispersion was smaller, and the fatigue life was greatly increased.
Three-point bending fatigue test was carried out on basalt fiber reinforced concrete specimens with four kinds of fiber contents under three stress levels. Mathematical statistics was used to test the Weibull distribution of the bending fatigue life on the fatigue test data, and fitting the double logarithmic fatigue equation under different failure probabilities. The results showed that the bending fatigue life of basalt fiber reinforced concrete conformed to the two-parameter Weibull distribution, as the stress level decreased, the Weibull shape parameter first decreased and then increased, the dispersion of bending fatigue life first increased and then decreased; with the increase of fiber content, the distribution of bending fatigue life was more uniform, the dispersion was smaller, and the fatigue life was greatly increased.
2022, 52(7): 192-198.
doi: 10.13204/j.gyjzg21101009
Abstract:
A deep convolutional neural network damage identification method considering residual learning was proposed and applied to the damage identification of the frame structure joints. The proposed method was deeply discussed by means of experimental research, and the results showed that this method could solve the problems of convergence difficulty and poor recognition accuracy caused by the network degradation and gradient explosion, dispersion problems when the network deepening. In the comparative study of joint damage identification of test frame, the convergence speed and accuracy of deep convolutional neural network considering residual learning were higher than those of shallow conventional neural network and deep neural network, and had high accuracy and stability, and increased the possibilities to build a deeper and more complex network for damage diagnosis of complex structures in engineering. In addition, in order to improve the quality and quantity of training samples for network, a new data processing method was proposed according to the law of sample division. This method could significantly increase the sample size for training, weaken the information loss caused by data truncation under the same conditions, and greatly improve the recognition accuracy and convergence speed, and the research showed its effectiveness and applicability.
A deep convolutional neural network damage identification method considering residual learning was proposed and applied to the damage identification of the frame structure joints. The proposed method was deeply discussed by means of experimental research, and the results showed that this method could solve the problems of convergence difficulty and poor recognition accuracy caused by the network degradation and gradient explosion, dispersion problems when the network deepening. In the comparative study of joint damage identification of test frame, the convergence speed and accuracy of deep convolutional neural network considering residual learning were higher than those of shallow conventional neural network and deep neural network, and had high accuracy and stability, and increased the possibilities to build a deeper and more complex network for damage diagnosis of complex structures in engineering. In addition, in order to improve the quality and quantity of training samples for network, a new data processing method was proposed according to the law of sample division. This method could significantly increase the sample size for training, weaken the information loss caused by data truncation under the same conditions, and greatly improve the recognition accuracy and convergence speed, and the research showed its effectiveness and applicability.
2022, 52(7): 199-203.
doi: 10.13204/j.gyjzg21090610
Abstract:
By analyzing the existing problems of biomedical industrial parks on the market, the importance of stimulating site vitality and creating a distinctive atmosphere for innovative biomedical park was explained. On this basis, the design strategy of innovative biomedical industry park vitality creation was summarized. Combined with the Beijing Yizhuang Cell Therapy R&D Pilot Base Project, the paper explored how to create an innovative industrial community with unique vitality and place spirit.
By analyzing the existing problems of biomedical industrial parks on the market, the importance of stimulating site vitality and creating a distinctive atmosphere for innovative biomedical park was explained. On this basis, the design strategy of innovative biomedical industry park vitality creation was summarized. Combined with the Beijing Yizhuang Cell Therapy R&D Pilot Base Project, the paper explored how to create an innovative industrial community with unique vitality and place spirit.
2022, 52(7): 204-207.
doi: 10.13204/j.gyjzg21043008
Abstract:
Shenzhen is a karst-prone city in China. The karsts are mainly developed in the eastern region and are mainly covered karsts. The poor engineering geological conditions have brought many unfavorable conditions to the construction projects. In order to analyze the technology of karst foundation treatment in Shenzhen, foundation pit project in Shenzhen was taken as an example. First, the karst geological development of the project site was comprehensively analyzed through detailed geotechnical engineering survey, geological drilling and geophysical exploration. Then, the method of using high-pressure grouting was proposed for karst cave treatment. The overall foundation adopted CFG pile composite foundation + raft foundation to jointly exert the bearing effect of CFG pile and soil between piles, so as to improve the bearing capacity of the karst formation.
Shenzhen is a karst-prone city in China. The karsts are mainly developed in the eastern region and are mainly covered karsts. The poor engineering geological conditions have brought many unfavorable conditions to the construction projects. In order to analyze the technology of karst foundation treatment in Shenzhen, foundation pit project in Shenzhen was taken as an example. First, the karst geological development of the project site was comprehensively analyzed through detailed geotechnical engineering survey, geological drilling and geophysical exploration. Then, the method of using high-pressure grouting was proposed for karst cave treatment. The overall foundation adopted CFG pile composite foundation + raft foundation to jointly exert the bearing effect of CFG pile and soil between piles, so as to improve the bearing capacity of the karst formation.
2022, 52(7): 208-214.
doi: 10.13204/j.gyjzG21080310
Abstract:
At present, China has entered the era of stock planning. How to scientifically and effectively reuse industrial remains has become one of the key points and difficulties in China's urban planning industry. As the world's largest industrialized country, the United Kingdom has a well-established industrial heritage protection management system. Based on this, the paper selected the world heritage "Saltaire Industrial Heritage Area" in the British textile industry era as an example, and interpreted its construction background, current situation and value composition; the protection and management mode of the adaptive reuse of Saltaire Industrial Heritage Area was analyzed and explored from the three dimensions of protection strategy, environmental capacity assessment and operation management mode of industrial heritage area. Finally, the paper proposed a proposal from three aspects:protection measures and strategies, environmental capacity assessment scheme, and scientific and effective operation management mode.
At present, China has entered the era of stock planning. How to scientifically and effectively reuse industrial remains has become one of the key points and difficulties in China's urban planning industry. As the world's largest industrialized country, the United Kingdom has a well-established industrial heritage protection management system. Based on this, the paper selected the world heritage "Saltaire Industrial Heritage Area" in the British textile industry era as an example, and interpreted its construction background, current situation and value composition; the protection and management mode of the adaptive reuse of Saltaire Industrial Heritage Area was analyzed and explored from the three dimensions of protection strategy, environmental capacity assessment and operation management mode of industrial heritage area. Finally, the paper proposed a proposal from three aspects:protection measures and strategies, environmental capacity assessment scheme, and scientific and effective operation management mode.
2022, 52(7): 215-219,16.
doi: 10.13204/j.gyjzG21102006
Abstract:
Old Ashikaga City Model Twisting Silk Factory is an important historical building which witnessed the development of textile industry in the western regions of Kitakantou, Japan. Based on architectural investigation and historical data investigation, the background of the construction of the heritage site was sorted out and its heritage value was analyzed. On this basis, from the perspective of single heritage protection, the paper studied and analyzes the regeneration of the external space and the internal space of the heritage site, and the key implementation strategies of China's industrial heritage protection were discussed.
Old Ashikaga City Model Twisting Silk Factory is an important historical building which witnessed the development of textile industry in the western regions of Kitakantou, Japan. Based on architectural investigation and historical data investigation, the background of the construction of the heritage site was sorted out and its heritage value was analyzed. On this basis, from the perspective of single heritage protection, the paper studied and analyzes the regeneration of the external space and the internal space of the heritage site, and the key implementation strategies of China's industrial heritage protection were discussed.
2022, 52(7): 220-226,78.
doi: 10.13204/j.gyjzG20032303
Abstract:
A detailed interpretation of the slow environment in the world-famous German town of Bad Wörishofen was conducted. In the context of reaching a consensus on the concept that the environment can affect people's health and the slow system is strongly advocated, in order to promote the construction of the slow system in China and make the slow environment better play the health benefits. The research on the strategy of creating healthy atmosphere in slow environment was conducted, as well as the analysis of environment and facilities of featured slow line. It was found that the following strategies could be used to create a healthy atmosphere in slow walking environment:1) distinct health concept, choice of various sports and exercise activities, active use of natural environment intervention, distinct health theme of service facilities, combined with exercise therapy, etc; 2) the featured slow line should carry out these strategies and display them vividly.
A detailed interpretation of the slow environment in the world-famous German town of Bad Wörishofen was conducted. In the context of reaching a consensus on the concept that the environment can affect people's health and the slow system is strongly advocated, in order to promote the construction of the slow system in China and make the slow environment better play the health benefits. The research on the strategy of creating healthy atmosphere in slow environment was conducted, as well as the analysis of environment and facilities of featured slow line. It was found that the following strategies could be used to create a healthy atmosphere in slow walking environment:1) distinct health concept, choice of various sports and exercise activities, active use of natural environment intervention, distinct health theme of service facilities, combined with exercise therapy, etc; 2) the featured slow line should carry out these strategies and display them vividly.
2022, 52(7): 227-232.
doi: 10.13204/j.gyjzG22052903
Abstract:
As a public area of great significance to urban development, campus plays an important role in history, culture, and environment. According to the cultural background and ecological environment of the city where the campus is located, the campus is divided into different types, and the campus planning also forms different strategies. The factors affecting campus planning come from the relationship between users and the campus environment, which not only represents the image of the city where the campus is located, but also involves social, ecological, educational and financial issues. In the past three decades, many colleges and universities have renovated or expanded their campuses, and different types of campuses have adopted different planning and design strategies. Through the investigation and evaluation of three typical European campus planning cases, the paper discussed how to balance the relationship between various influencing factors in the process of campus planning, while meeting the local cultural characteristics and ecological attributes.
As a public area of great significance to urban development, campus plays an important role in history, culture, and environment. According to the cultural background and ecological environment of the city where the campus is located, the campus is divided into different types, and the campus planning also forms different strategies. The factors affecting campus planning come from the relationship between users and the campus environment, which not only represents the image of the city where the campus is located, but also involves social, ecological, educational and financial issues. In the past three decades, many colleges and universities have renovated or expanded their campuses, and different types of campuses have adopted different planning and design strategies. Through the investigation and evaluation of three typical European campus planning cases, the paper discussed how to balance the relationship between various influencing factors in the process of campus planning, while meeting the local cultural characteristics and ecological attributes.
