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2010 Vol. 40, No. 12
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2010, 40(12): 1-3.
doi: 10.13204/j.gyjz201012001
Abstract:
The energy consumption of building is very large.Implementation of building energy conservation has important significance to decrease the energy consumption and protect environment.Starting from the social fairness it is pointed out that different technical standards of building energy-saving should be used for different quality level of buildings.More strict index demands should be given to high quality buildings,to control building energy consumption per unit building area.So the state should publish a series of incentive measures,establish the working and regulatory system,invest a lot of money;establish the standard of building energy-saving and perfect legal system of building energy-saving.
The energy consumption of building is very large.Implementation of building energy conservation has important significance to decrease the energy consumption and protect environment.Starting from the social fairness it is pointed out that different technical standards of building energy-saving should be used for different quality level of buildings.More strict index demands should be given to high quality buildings,to control building energy consumption per unit building area.So the state should publish a series of incentive measures,establish the working and regulatory system,invest a lot of money;establish the standard of building energy-saving and perfect legal system of building energy-saving.
2010, 40(12): 4-7.
doi: 10.13204/j.gyjz201012002
Abstract:
Huainan is an old haunt with a long history and civilization,and is also an important energy base in China.By studying the old city of Huainan,there are many abandoned factories.In view of this situation,what should be taken is the development of eradication,or reconstruction.The program gives full play to cultural values and economic values of Huainan,and takes account of geographical features of the city,whose buildings will be transformed in the way of reservation-recycle-recreation,so that the sustainable development idea of energy saving enjoys popular support.Reuse of old buildings is a necessary process for the citys current transformation and development,which can raise the citys historical and cultural features.
Huainan is an old haunt with a long history and civilization,and is also an important energy base in China.By studying the old city of Huainan,there are many abandoned factories.In view of this situation,what should be taken is the development of eradication,or reconstruction.The program gives full play to cultural values and economic values of Huainan,and takes account of geographical features of the city,whose buildings will be transformed in the way of reservation-recycle-recreation,so that the sustainable development idea of energy saving enjoys popular support.Reuse of old buildings is a necessary process for the citys current transformation and development,which can raise the citys historical and cultural features.
ENERGY EFFICIENCY REFORMATION FOR EXTERNAL STRUCTURES OF OLD FACTORY BUILDINGS IN SEVERE COLD REGION
2010, 40(12): 8-12.
doi: 10.13204/j.gyjz201012003
Abstract:
Old factory buildings in severe cold region are facing historic choice to be repaired,be torn down and be protected.Because of the geography and weather factors,the enclosures of these factory buildings have insulation function and historic characteristics.Adopting the reasonable and viable development countermeasures is the key to the correct development.Through investigation and research,experiment and test,practicable reformation measures,can be got,which will make the old factory buildings have a sustainable development,thus attaining the purpose of energy-saving and beautifying city in the process of city development.
Old factory buildings in severe cold region are facing historic choice to be repaired,be torn down and be protected.Because of the geography and weather factors,the enclosures of these factory buildings have insulation function and historic characteristics.Adopting the reasonable and viable development countermeasures is the key to the correct development.Through investigation and research,experiment and test,practicable reformation measures,can be got,which will make the old factory buildings have a sustainable development,thus attaining the purpose of energy-saving and beautifying city in the process of city development.
2010, 40(12): 13-15.
doi: 10.13204/j.gyjz201012004
Abstract:
It has been proposed the energy-saving strategies of high-rise office buildings,which can adapt to local climatic characteristics through an investigation on the present status of the high-rise office buildngs in Xian City,and also by way of the analysis of the existing main problems.Which would provide useful experience for the energy-saving design of high-rise office buildings.
It has been proposed the energy-saving strategies of high-rise office buildings,which can adapt to local climatic characteristics through an investigation on the present status of the high-rise office buildngs in Xian City,and also by way of the analysis of the existing main problems.Which would provide useful experience for the energy-saving design of high-rise office buildings.
2010, 40(12): 16-18,38.
doi: 10.13204/j.gyjz201012005
Abstract:
It has been conducted that some technical trials of the improvement on the traditional constructing artifices,as well as the use of technical and ecological artifices by means of an actual case.The experience and lessons obtained have also been discussed.
It has been conducted that some technical trials of the improvement on the traditional constructing artifices,as well as the use of technical and ecological artifices by means of an actual case.The experience and lessons obtained have also been discussed.
2010, 40(12): 19-21.
doi: 10.13204/j.gyjz201012006
Abstract:
According to the northeast climate characteristics and natural conditions in rural areas and the working principle of solar house,this paper designed the house type and structure of rural houses to use effectively solar energy for solving the problems of winter heating and summer cooling of rural houses.In addition,it was analyzed the economic benefit by solar energy.Through the pilot project,it has been proved that the solar house design can improve greatly the thermal performance of a rural house,reduce the energy consumption of rural house for winter heating and adjust its summer indoor temperature to achieve the purpose of energy-saving,environmental protection and low cost.Hence it is feasible to take the road of sustainable development.
According to the northeast climate characteristics and natural conditions in rural areas and the working principle of solar house,this paper designed the house type and structure of rural houses to use effectively solar energy for solving the problems of winter heating and summer cooling of rural houses.In addition,it was analyzed the economic benefit by solar energy.Through the pilot project,it has been proved that the solar house design can improve greatly the thermal performance of a rural house,reduce the energy consumption of rural house for winter heating and adjust its summer indoor temperature to achieve the purpose of energy-saving,environmental protection and low cost.Hence it is feasible to take the road of sustainable development.
2010, 40(12): 22-24,33.
doi: 10.13204/j.gyjz201012007
Abstract:
Qinghai Province is located in a arctic region,where most of the formers and herdsmen have poor resident conditions with backward economy,who have only original mode of energy with single structure.There also is a had lack of energy in the region.Passive solar heating technology is the applied one that is relatively simple,practical,effective,and can compete with conventional energy sources.It is analyzed in-depth the actual use of passive solar heating technology by way of an investigation on partial passive solar projects in Qinghai Province.
Qinghai Province is located in a arctic region,where most of the formers and herdsmen have poor resident conditions with backward economy,who have only original mode of energy with single structure.There also is a had lack of energy in the region.Passive solar heating technology is the applied one that is relatively simple,practical,effective,and can compete with conventional energy sources.It is analyzed in-depth the actual use of passive solar heating technology by way of an investigation on partial passive solar projects in Qinghai Province.
2010, 40(12): 25-27,83.
doi: 10.13204/j.gyjz201012008
Abstract:
It was presented the material,tructure and use of a prefabricated insulation-decoration panel,and expounded the construction technique of the panel,combining with the construction of the prefabricated panels for the decoration of the building of Maternity and Child Health Center in Jiexiu County of Shanxi Province.It was also pointed out the significance of this sort of prefabricated panel to the creative energy-saving of the decoration of a modern architecture.
It was presented the material,tructure and use of a prefabricated insulation-decoration panel,and expounded the construction technique of the panel,combining with the construction of the prefabricated panels for the decoration of the building of Maternity and Child Health Center in Jiexiu County of Shanxi Province.It was also pointed out the significance of this sort of prefabricated panel to the creative energy-saving of the decoration of a modern architecture.
2010, 40(12): 28-33.
doi: 10.13204/j.gyjz201012009
Abstract:
Traditional random vibration method requires a large number of numerical integrations,which is very time-consuming in multi-excitation analysis.Based on closed-form integration for polynomial-type power spectral density functions in log-log scales,a robust integration technique which has been applied in ANSYS can overcome these drawbacks and has been verified to be efficient and accurate.The stochastic responses of corridors of connected high-rise structures under multi-support excitations of bilateral horizontal seismic action are numerically simulated by the technique in this paper.The mean of maximum and variance response values obtained from the spatially varying earthquake ground motions are compared.The results show that the axial forces of the bars of the corridors have been increased when considering the wave-passage and the partial coherence,so the spatially varying earthquake ground motions should be considered in the analysis.
Traditional random vibration method requires a large number of numerical integrations,which is very time-consuming in multi-excitation analysis.Based on closed-form integration for polynomial-type power spectral density functions in log-log scales,a robust integration technique which has been applied in ANSYS can overcome these drawbacks and has been verified to be efficient and accurate.The stochastic responses of corridors of connected high-rise structures under multi-support excitations of bilateral horizontal seismic action are numerically simulated by the technique in this paper.The mean of maximum and variance response values obtained from the spatially varying earthquake ground motions are compared.The results show that the axial forces of the bars of the corridors have been increased when considering the wave-passage and the partial coherence,so the spatially varying earthquake ground motions should be considered in the analysis.
2010, 40(12): 34-38.
doi: 10.13204/j.gyjz201012010
Abstract:
Twelve finite element models of a ten-story frame structure were set up to investigate the influences on its horizontal stiffness of the filled wall under different seismic waves.The main influential factors included the walls material,its spatial arrangement,and its quantity in every story.Results indicate that from standard brick to hollow brick and aerated concrete block,the effect on changing stiffness of filled wears materials becomes smaller and smaller,but its influences cannot be ignored.When the cross-section ratio of first layers filled wall to next layers filled wall is smaller than 45%,the layer should be treaded as weak layer.The cross-section ratio can be equal or greater than 60% in design.Based on numerical analysis,the formulas for calculating horizontal stiffness are presented,on which the influences of filled wall are given.
Twelve finite element models of a ten-story frame structure were set up to investigate the influences on its horizontal stiffness of the filled wall under different seismic waves.The main influential factors included the walls material,its spatial arrangement,and its quantity in every story.Results indicate that from standard brick to hollow brick and aerated concrete block,the effect on changing stiffness of filled wears materials becomes smaller and smaller,but its influences cannot be ignored.When the cross-section ratio of first layers filled wall to next layers filled wall is smaller than 45%,the layer should be treaded as weak layer.The cross-section ratio can be equal or greater than 60% in design.Based on numerical analysis,the formulas for calculating horizontal stiffness are presented,on which the influences of filled wall are given.
2010, 40(12): 39-42.
doi: 10.13204/j.gyjz201012011
Abstract:
In current design codes,column moment magnification coefficient is provided for in accord with the fundamental law of strong column-weak beam of reinforced concrete structure.However,in actual projects,the real beam moment is usually larger than the designed moment,and the magnification coefficient of beam moment may be larger than that of column moment in code,which results in column-hinge failure mechanism when an earthquake occurs.The effects of the pressed reinforcing bars in beams and bars in concrete slabs were analyzed on flexural bearing capacity,the beam moment magnification coefficicent was calculated and compared with that of column moment.The discussion on column moment magnification coefficient was carried out and some advices were put forward.
In current design codes,column moment magnification coefficient is provided for in accord with the fundamental law of strong column-weak beam of reinforced concrete structure.However,in actual projects,the real beam moment is usually larger than the designed moment,and the magnification coefficient of beam moment may be larger than that of column moment in code,which results in column-hinge failure mechanism when an earthquake occurs.The effects of the pressed reinforcing bars in beams and bars in concrete slabs were analyzed on flexural bearing capacity,the beam moment magnification coefficicent was calculated and compared with that of column moment.The discussion on column moment magnification coefficient was carried out and some advices were put forward.
2010, 40(12): 43-46,54.
doi: 10.13204/j.gyjz201012012
Abstract:
Base isolation is restricted on large aspect ratio structure due to the fact that the tensile ability of the laminated rubber bearing is poor.An innovation tensile-resistant device for laminated rubber bearing(TRDLRB) is proposed by way of taking advantage of compressive ability to resist the tensile force.Nonlinear dynamic analysis of an isolated high-rise building under severe earthquake loading is performed in this paper to study the effects of the TRDLRB.The analysis results show that,the TRDLRB is feasible because of the simple in both design and manufacture,and the vertical displacement of the isolation layer is reduced despite the tensile force caused by superstructure using TRDLRB.The study also shows that the dynamic response of the isolated high-rise building is reduced remarkably and the tensile ability of the isolation layer is improved significantly.
Base isolation is restricted on large aspect ratio structure due to the fact that the tensile ability of the laminated rubber bearing is poor.An innovation tensile-resistant device for laminated rubber bearing(TRDLRB) is proposed by way of taking advantage of compressive ability to resist the tensile force.Nonlinear dynamic analysis of an isolated high-rise building under severe earthquake loading is performed in this paper to study the effects of the TRDLRB.The analysis results show that,the TRDLRB is feasible because of the simple in both design and manufacture,and the vertical displacement of the isolation layer is reduced despite the tensile force caused by superstructure using TRDLRB.The study also shows that the dynamic response of the isolated high-rise building is reduced remarkably and the tensile ability of the isolation layer is improved significantly.
2010, 40(12): 47-50.
doi: 10.13204/j.gyjz201012013
Abstract:
According to the shear performance test of ordinary concrete beam,this paper designed and condusted the shear performance test of 7 recycled concrete beams which were simply supported,it was studied the forced characteristics and shear failure mechanism of recycled concrete beams,and analysis the influence of recycled aggregate replacement to the shear properties.Finally,it was discussed the shear strength calculation formula of recycled concrete beam,and considered that the shear strength formula of ordinary concrete beam in the Code for Design of Concrete Structures(GB 500102002) can still be used for recycled concrete beam,it contains a certain security reserve,and based on engineering requirement,is was suggested that a more applicable shear formula should be used for recycled concrete beam.
According to the shear performance test of ordinary concrete beam,this paper designed and condusted the shear performance test of 7 recycled concrete beams which were simply supported,it was studied the forced characteristics and shear failure mechanism of recycled concrete beams,and analysis the influence of recycled aggregate replacement to the shear properties.Finally,it was discussed the shear strength calculation formula of recycled concrete beam,and considered that the shear strength formula of ordinary concrete beam in the Code for Design of Concrete Structures(GB 500102002) can still be used for recycled concrete beam,it contains a certain security reserve,and based on engineering requirement,is was suggested that a more applicable shear formula should be used for recycled concrete beam.
2010, 40(12): 51-54.
doi: 10.13204/j.gyjz201012014
Abstract:
Based on the data of six HRBF500 RC columns cycle loading test,yield displacement and hysteretic energy of columns are calculated at the different axial compression ratio,shear span ratio and stirrup ratio.According to some problems of the classical model,scale parameter is proposed to coordinate the displacements of cycle loading and monotonic loading for amending the classical model.The columnsdamage process is analyzed by the amended dynamic model.The trend and law of the damage process are summarized considering the effect of axial compression ratio,shear span ratio and stirrup ratio.Finally the criterion for evaluation and design proposals are given.
Based on the data of six HRBF500 RC columns cycle loading test,yield displacement and hysteretic energy of columns are calculated at the different axial compression ratio,shear span ratio and stirrup ratio.According to some problems of the classical model,scale parameter is proposed to coordinate the displacements of cycle loading and monotonic loading for amending the classical model.The columnsdamage process is analyzed by the amended dynamic model.The trend and law of the damage process are summarized considering the effect of axial compression ratio,shear span ratio and stirrup ratio.Finally the criterion for evaluation and design proposals are given.
2010, 40(12): 55-59.
doi: 10.13204/j.gyjz201012015
Abstract:
Up to now,in all codes for design of dynamic machine foundation,the effect of variation of pressure in soils at various depths under foundation base on the value Cz of the coefficient of elastic uniform compression of base was not considered.All these codes of design only considered the effect of area of foundation base on the coefficient Cz.However,the results of research of this paper verify that the coefficient of elastic uniform compression depends not only on the area of foundation base but also on the acting pressure on soils.When determing the coefficient Cz,considering the effect of pressure on soil is fully necessary.On the basis of that one,the precision degree of computing of foundation vibration will be improved considerably.
Up to now,in all codes for design of dynamic machine foundation,the effect of variation of pressure in soils at various depths under foundation base on the value Cz of the coefficient of elastic uniform compression of base was not considered.All these codes of design only considered the effect of area of foundation base on the coefficient Cz.However,the results of research of this paper verify that the coefficient of elastic uniform compression depends not only on the area of foundation base but also on the acting pressure on soils.When determing the coefficient Cz,considering the effect of pressure on soil is fully necessary.On the basis of that one,the precision degree of computing of foundation vibration will be improved considerably.
2010, 40(12): 60-64,42.
doi: 10.13204/j.gyjz201012016
Abstract:
Peck method and Stochastic Medium Model(SMM) were widely used for predicting ground movement induced by shield tunneling in China.But it is difficult to determine the parameters of this two methods.So the relation between tunnel relative depth and maximum surface settlement was plotted according to 46 measured engineering cases.It shows that ground settlements induced by shield tunneling change greatly when tunnel relative depths are less than 5;influence of tunnel relative depth is little when it is greater than 5.Based on the maximum surface settlement calculating formula of soil non-uniform convergence model,and according to Peck and SMM method,an applied calculation method was deduced,which considered the influence of all different soil conditions,tunnel radius and depth,whose rationality was validated by the analysis of 5 engineering cases.
Peck method and Stochastic Medium Model(SMM) were widely used for predicting ground movement induced by shield tunneling in China.But it is difficult to determine the parameters of this two methods.So the relation between tunnel relative depth and maximum surface settlement was plotted according to 46 measured engineering cases.It shows that ground settlements induced by shield tunneling change greatly when tunnel relative depths are less than 5;influence of tunnel relative depth is little when it is greater than 5.Based on the maximum surface settlement calculating formula of soil non-uniform convergence model,and according to Peck and SMM method,an applied calculation method was deduced,which considered the influence of all different soil conditions,tunnel radius and depth,whose rationality was validated by the analysis of 5 engineering cases.
2010, 40(12): 65-69.
doi: 10.13204/j.gyjz201012017
Abstract:
Accurate choosing value on shear strength parameters have significant influence on slope stability analysis,which is especially true for the analysis of high fills constructed in mountainous region.The Mohr-Coulomb failure envelope for rockfill which is widely used in high fills is obviously nonlinear.Only using nonlinear shear strength criterion,can the real safe state of slope be well reflected.Analysis method based on logarithmic relationship advanced by Duncan in limit equilibrium method was studied.The differences in slope stability analysis by the linear and nonlinear criteria were discussed.The results of a series of calculation examples show that the confining pressure should be taken into account when the linear shear strength parameters are chosen,and the linear criterion without cohesion c is not appropriate for high fills of rockfill.
Accurate choosing value on shear strength parameters have significant influence on slope stability analysis,which is especially true for the analysis of high fills constructed in mountainous region.The Mohr-Coulomb failure envelope for rockfill which is widely used in high fills is obviously nonlinear.Only using nonlinear shear strength criterion,can the real safe state of slope be well reflected.Analysis method based on logarithmic relationship advanced by Duncan in limit equilibrium method was studied.The differences in slope stability analysis by the linear and nonlinear criteria were discussed.The results of a series of calculation examples show that the confining pressure should be taken into account when the linear shear strength parameters are chosen,and the linear criterion without cohesion c is not appropriate for high fills of rockfill.
2010, 40(12): 70-74.
doi: 10.13204/j.gyjz201012018
Abstract:
Taking account of concrete cube strength and coarse aggregate replacement rate,tensile strength and shear strength property of recycled aggregate concrete had researched.In this paper,the tensile samples were standard cube,bending strength test used non-standard samples,section of the shear test beams was uniform depth and varying width.The stress strength and the strain of the test samples were researched.The following results were obtained: 1) the split strength of recycled concrete was lower than the natural aggregate concrete;2) bending strength of recycled concrete had a large range discrete,a reasonable regression formula could not be found;3) the ultimate shear stress was not changed with the replacement variation,regression of the shear strength and the cube strength had a lower relationship coefficient;4) the shear stress-principal strain curve of sample beams was a line when the indicated value was less than about 70% maximum value,the measured nominal stress of shear and shear modulus of elasticity were lower than natural coarse concrete.
Taking account of concrete cube strength and coarse aggregate replacement rate,tensile strength and shear strength property of recycled aggregate concrete had researched.In this paper,the tensile samples were standard cube,bending strength test used non-standard samples,section of the shear test beams was uniform depth and varying width.The stress strength and the strain of the test samples were researched.The following results were obtained: 1) the split strength of recycled concrete was lower than the natural aggregate concrete;2) bending strength of recycled concrete had a large range discrete,a reasonable regression formula could not be found;3) the ultimate shear stress was not changed with the replacement variation,regression of the shear strength and the cube strength had a lower relationship coefficient;4) the shear stress-principal strain curve of sample beams was a line when the indicated value was less than about 70% maximum value,the measured nominal stress of shear and shear modulus of elasticity were lower than natural coarse concrete.
2010, 40(12): 75-78.
doi: 10.13204/j.gyjz201012019
Abstract:
In this study,pull-out tests are carried out to research the bond behavior between steel bar and frozen concrete during winter construction.Test parameters are construction temperature,amount of anti-freezing admixture and curing condition.load-slip curve of steel bar and concrete is obtained,and factors such as ultimate bond strength and bond slip are analyzed and compared with specimens in standard curing condition.The test results show that bond properties between steel bar and concrete are degenerated due to inadequate amount of anti-freezing admixture and poor curing condition in low temperature.
In this study,pull-out tests are carried out to research the bond behavior between steel bar and frozen concrete during winter construction.Test parameters are construction temperature,amount of anti-freezing admixture and curing condition.load-slip curve of steel bar and concrete is obtained,and factors such as ultimate bond strength and bond slip are analyzed and compared with specimens in standard curing condition.The test results show that bond properties between steel bar and concrete are degenerated due to inadequate amount of anti-freezing admixture and poor curing condition in low temperature.
2010, 40(12): 79-83.
doi: 10.13204/j.gyjz201012020
Abstract:
The integral sliding form construction technology of integrating automatic hydraulic control system with pumping and pouring concrete by separatory bin etc was used for the construction of six connected silos of Xiushan Sanlei Cement Co.in Chongqing.Excellent results were obtained in the actual use of this project,which provided a powerful guarantee for the requirements of quality and time limit for the project.
The integral sliding form construction technology of integrating automatic hydraulic control system with pumping and pouring concrete by separatory bin etc was used for the construction of six connected silos of Xiushan Sanlei Cement Co.in Chongqing.Excellent results were obtained in the actual use of this project,which provided a powerful guarantee for the requirements of quality and time limit for the project.
2010, 40(12): 84-86,15.
doi: 10.13204/j.gyjz201012021
Abstract:
Through application of the 11.5 m long cantilever beam in China Jiyuan Basket-Ball City,the construction project and design method about steel-concrete-pestress large cantilever beam was depicted;the composite tension scheme combining vertical tension on the top of steel with horizontal tension to bonded string and measure ensuring structure working together was explored.It is the optimizing structural concept of the big cantilever structure,the long-span beam or the big eccentric structure or the transformation structure for the load of frequent change,and high efficiency prestressed technique is the initiative measure to guarantee the collaborating structure,steel pressure forced displacement method can give full play to the steel tensile strength and improve the anticrack and deformation performance of the structure.
Through application of the 11.5 m long cantilever beam in China Jiyuan Basket-Ball City,the construction project and design method about steel-concrete-pestress large cantilever beam was depicted;the composite tension scheme combining vertical tension on the top of steel with horizontal tension to bonded string and measure ensuring structure working together was explored.It is the optimizing structural concept of the big cantilever structure,the long-span beam or the big eccentric structure or the transformation structure for the load of frequent change,and high efficiency prestressed technique is the initiative measure to guarantee the collaborating structure,steel pressure forced displacement method can give full play to the steel tensile strength and improve the anticrack and deformation performance of the structure.
2010, 40(12): 87-89,122.
doi: 10.13204/j.gyjz201012022
Abstract:
Utilizing finite element program,this article analyze displacements of complex wall cladding in horizontal load,discusses the influence of thickness of structural layer,horizontal truss,vertical truss and steel net,it has been found by analysis that the main influence factor of wall cladding stiffness is thickness of structural layer,second factor is horizontal truss,other factors have less influence,it provides a theoretic basis for development of new type of complex wall cladding.
Utilizing finite element program,this article analyze displacements of complex wall cladding in horizontal load,discusses the influence of thickness of structural layer,horizontal truss,vertical truss and steel net,it has been found by analysis that the main influence factor of wall cladding stiffness is thickness of structural layer,second factor is horizontal truss,other factors have less influence,it provides a theoretic basis for development of new type of complex wall cladding.
2010, 40(12): 90-94.
doi: 10.13204/j.gyjz201012023
Abstract:
Based on flexibility and fiber model,the beam-column element of the modeling methods for concrete-filled steel tube columns is researched and a parametric analysis is carried out by Opensees software.The effects of the constitutive relationship of material,the mesh division of fiber cross-section and the number of integration points on the simulation precision and the calculation efficiency are discussed.The results show that the descending section of confined concrete constitutive relationship and the enhancing section of steel constitutive relationship are the main factors which affect the accuracy of hysteretic model.On the other hand,both the mesh division of fiber cross-section and the number of integration points affect the calculation efficiency.The research can supply a theoretic basis for the use of this sort of element in a composite structure.
Based on flexibility and fiber model,the beam-column element of the modeling methods for concrete-filled steel tube columns is researched and a parametric analysis is carried out by Opensees software.The effects of the constitutive relationship of material,the mesh division of fiber cross-section and the number of integration points on the simulation precision and the calculation efficiency are discussed.The results show that the descending section of confined concrete constitutive relationship and the enhancing section of steel constitutive relationship are the main factors which affect the accuracy of hysteretic model.On the other hand,both the mesh division of fiber cross-section and the number of integration points affect the calculation efficiency.The research can supply a theoretic basis for the use of this sort of element in a composite structure.
2010, 40(12): 95-97.
doi: 10.13204/j.gyjz201012024
Abstract:
This text states the general method of linear controls of steel structure manufacturing both at home and abroad,analyzes the arch model of the exhibition halls steel box beam structure with pre-camber using finite element software of ANSYS,calculates the deformation of steel box beam structure subjected to its weight,which proves that the results match the formula very well,and provides a basis for structure pre-camber designs.
This text states the general method of linear controls of steel structure manufacturing both at home and abroad,analyzes the arch model of the exhibition halls steel box beam structure with pre-camber using finite element software of ANSYS,calculates the deformation of steel box beam structure subjected to its weight,which proves that the results match the formula very well,and provides a basis for structure pre-camber designs.
2010, 40(12): 98-101.
doi: 10.13204/j.gyjz201012025
Abstract:
In the new century,the buildingsdisaster prevention affects the whole countrycapacity of resisting disaster due to the fact that the globe faces more serious situation of calamity.Calculation design and concept design in Code for Seismic Design of Buildings(GB 500112001) and Technical Specification for Concrete Structures of Tall Building(JGJ 32002) guarantee the basic prevention capacity for constructions in anti-seismic zone.However,for the multistory buildings in non-earthquake protection region there is no calculation for enhancement and little concept design for integrity in Code for Design of Concrete Structures(GB 500102002) and Code for Design of Masonry Structures(GB 500032001).Considering economic benefit,this paper suggests that concept design system should be used more in the two kinds of codes in order to improve the anti-disaster capacity of the multistory buildings in non-earthquake protection regions.
In the new century,the buildingsdisaster prevention affects the whole countrycapacity of resisting disaster due to the fact that the globe faces more serious situation of calamity.Calculation design and concept design in Code for Seismic Design of Buildings(GB 500112001) and Technical Specification for Concrete Structures of Tall Building(JGJ 32002) guarantee the basic prevention capacity for constructions in anti-seismic zone.However,for the multistory buildings in non-earthquake protection region there is no calculation for enhancement and little concept design for integrity in Code for Design of Concrete Structures(GB 500102002) and Code for Design of Masonry Structures(GB 500032001).Considering economic benefit,this paper suggests that concept design system should be used more in the two kinds of codes in order to improve the anti-disaster capacity of the multistory buildings in non-earthquake protection regions.
2010, 40(12): 102-106.
doi: 10.13204/j.gyjz201012026
Abstract:
A four-layer frame structure of benzene chloride workshop for Jinxi Chemical Plant reinforced with carbon fiber reinforced polymer(CFRP) is analyzed.Structure checking computations show that almost all members of the building must be reinforced except floor plate if it is used continuously as an industrial factory building.Reinforcing plan of beams and columns are presented in the design,and one of the max span beams is simulated with finite element method.The simulation shows that flexural bearing capacity of the beam reinforced by CFRP is improved effectively and the tensile stress is remarkably reduced of steel bar at bottom of beam.At the same time,the analysis of anti-seismic performance of the building by finite element simulation is completed between reinforced with and without CFRP.The simulations show that the CFRP can offer lateral resisting stiffness to reduce seismic response of the structure,and come up to seismic codes and standards.
A four-layer frame structure of benzene chloride workshop for Jinxi Chemical Plant reinforced with carbon fiber reinforced polymer(CFRP) is analyzed.Structure checking computations show that almost all members of the building must be reinforced except floor plate if it is used continuously as an industrial factory building.Reinforcing plan of beams and columns are presented in the design,and one of the max span beams is simulated with finite element method.The simulation shows that flexural bearing capacity of the beam reinforced by CFRP is improved effectively and the tensile stress is remarkably reduced of steel bar at bottom of beam.At the same time,the analysis of anti-seismic performance of the building by finite element simulation is completed between reinforced with and without CFRP.The simulations show that the CFRP can offer lateral resisting stiffness to reduce seismic response of the structure,and come up to seismic codes and standards.
2010, 40(12): 107-109.
doi: 10.13204/j.gyjz201012027
Abstract:
The bearing capacity and ductility can be obviously increased by the confinement of CFRP and angle steel.Based on the existing experimental data,the mechanical model and the confinement mechanism of concrete column reinforced by CFRP and angle steel are studied,the concept of effective confinement zone is introduced,and then the calculating method of effective confinement area of concrete column reinforced by CFRP or angle steel are respectively proposed.Therefore,the effect of CFRP layer,the area of angle steel,the rebar,and the shape of concrete column on bearing capacity are well considered,the calculating model for the bearing capacity of concrete column reinforced by CFRP and angle steel is established.The predictions of the model agree well with the experimental results,which may also provide the references for engineering practice.
The bearing capacity and ductility can be obviously increased by the confinement of CFRP and angle steel.Based on the existing experimental data,the mechanical model and the confinement mechanism of concrete column reinforced by CFRP and angle steel are studied,the concept of effective confinement zone is introduced,and then the calculating method of effective confinement area of concrete column reinforced by CFRP or angle steel are respectively proposed.Therefore,the effect of CFRP layer,the area of angle steel,the rebar,and the shape of concrete column on bearing capacity are well considered,the calculating model for the bearing capacity of concrete column reinforced by CFRP and angle steel is established.The predictions of the model agree well with the experimental results,which may also provide the references for engineering practice.
2010, 40(12): 110-112,3.
doi: 10.13204/j.gyjz201012028
Abstract:
The experiment on fatigue behavior of steel crane beam strengthened by CFRP has been carried out.In the paper,six steel beams are tested with different loads and reinforcement schemes.The result shows that fatigue damage of steel crane beam is brittle,whose stiffness will be decreased shapely and damage will accumulate largely when beam is close to fatigue failure.It also shows the fatigue life of steel crane beam strengthened by CFRP sheet can be increased by 52.94% ～ 85.56% as compared to un-reinforced of steel members.Load-strain curves and damage accumulated factor curves have been drawn.
The experiment on fatigue behavior of steel crane beam strengthened by CFRP has been carried out.In the paper,six steel beams are tested with different loads and reinforcement schemes.The result shows that fatigue damage of steel crane beam is brittle,whose stiffness will be decreased shapely and damage will accumulate largely when beam is close to fatigue failure.It also shows the fatigue life of steel crane beam strengthened by CFRP sheet can be increased by 52.94% ～ 85.56% as compared to un-reinforced of steel members.Load-strain curves and damage accumulated factor curves have been drawn.
2010, 40(12): 113-117.
doi: 10.13204/j.gyjz201012029
Abstract:
Based on the feasibility analysis and quantitative analysis of strengthening methods of frame beam after fire,the paper suggests a scientific strengthening method,i.e.,the carbon fiber reinforced polymer(CFRP).The paper then expounds the design and calculation of the strengthening with CFRP,the fire prevention and heat insulation with thin sheet,and the construction technology,etc.It is made a on-the-site static load test of frame beam before and after reinforcement,it is also examined and analysed the mechanical properties and deformation performance of the frame beam by comparing the bearing capacity,crack width and deflection.The research results show that frame beam with CFRP can improve the flexural capacity and shear-carrying capacity,delay the time of crack and minimize the crack width and deflection,which can ensure the security,applicability and durability.
Based on the feasibility analysis and quantitative analysis of strengthening methods of frame beam after fire,the paper suggests a scientific strengthening method,i.e.,the carbon fiber reinforced polymer(CFRP).The paper then expounds the design and calculation of the strengthening with CFRP,the fire prevention and heat insulation with thin sheet,and the construction technology,etc.It is made a on-the-site static load test of frame beam before and after reinforcement,it is also examined and analysed the mechanical properties and deformation performance of the frame beam by comparing the bearing capacity,crack width and deflection.The research results show that frame beam with CFRP can improve the flexural capacity and shear-carrying capacity,delay the time of crack and minimize the crack width and deflection,which can ensure the security,applicability and durability.
2010, 40(12): 118-122.
doi: 10.13204/j.gyjz201012030
Abstract:
Industrial heritage conservation and regeneration is a pressing subject in the rapid development of urbanization.At the macroscopic level,the paper analyzes the present situation and value factors in Shanxi Jinhua Textile Mill,puts forward the methods and strategies on its conservation and regeneration,i.e.Shanxi Modern National Industrial Museum is to be built at the same address,so as to give its full play to guide and promote its industrial heritage conservation and regeneration.
Industrial heritage conservation and regeneration is a pressing subject in the rapid development of urbanization.At the macroscopic level,the paper analyzes the present situation and value factors in Shanxi Jinhua Textile Mill,puts forward the methods and strategies on its conservation and regeneration,i.e.Shanxi Modern National Industrial Museum is to be built at the same address,so as to give its full play to guide and promote its industrial heritage conservation and regeneration.
2010, 40(12): 123-124,106.
doi: 10.13204/j.gyjz201012031
Abstract:
It has been expounded the necessity of using solar energy in rural houses during the construction of new rural areas,and also described the working principles and the use of solar energy.It is finally pointed out the problems of promoting solar energy at the present time,their solutions are also put forward.
It has been expounded the necessity of using solar energy in rural houses during the construction of new rural areas,and also described the working principles and the use of solar energy.It is finally pointed out the problems of promoting solar energy at the present time,their solutions are also put forward.
2010, 40(12): 125-128.
doi: 10.13204/j.gyjz201012032
Abstract:
This paper analyzes the role of the daylight which is applied in the underground space to ease negative psychological feelings,that easily occur in the underground space,such as the sense of closure,tension and anxiety etc,and to improve the environment quality of underground space.It is summarized the experience and patterns of application of daylight in the underground space and also explored how to introduce daylight external views downward to underground space through design techniques.
This paper analyzes the role of the daylight which is applied in the underground space to ease negative psychological feelings,that easily occur in the underground space,such as the sense of closure,tension and anxiety etc,and to improve the environment quality of underground space.It is summarized the experience and patterns of application of daylight in the underground space and also explored how to introduce daylight external views downward to underground space through design techniques.
