Login
Register
E-alert
2009 Vol. 39, No. 7
Display Method:
2009, 39(7): 1-3.
doi: 10.13204/j.gyjz200907001
Abstract:
Based on life-cycle energy analysis,circular economy theory and system engineering concept,it is presented that building energy-saving should be studied from the view of life-cycle.The current situation of building energy consumption at each stage in China is analyzed.Some feasible energy-saving measures are proposed according to respective details of various stages.
Based on life-cycle energy analysis,circular economy theory and system engineering concept,it is presented that building energy-saving should be studied from the view of life-cycle.The current situation of building energy consumption at each stage in China is analyzed.Some feasible energy-saving measures are proposed according to respective details of various stages.
2009, 39(7): 4-6.
doi: 10.13204/j.gyjz200907002
Abstract:
It is an important approach to reconstruct the energy-saving heating system of an existing residential building in reducing its energy consumption.The technology of energy-saving reconstruction consists of two aspects,one is architectural energy-saving,and the other is heating energy-saving.Energy-saving reconstruction mainly takes the energy-saving reconstruction of envelope structure and renewable energy sources into consideration.It plays a key role in analyzing the comprehensive efficiency and reasonable technology in the process of reconstruction.It is analyzed the technology of energy-saving reconstruction of wall for envelope structure,and put forward some measures in energy-saving reconstruction of existing residential buildings.
It is an important approach to reconstruct the energy-saving heating system of an existing residential building in reducing its energy consumption.The technology of energy-saving reconstruction consists of two aspects,one is architectural energy-saving,and the other is heating energy-saving.Energy-saving reconstruction mainly takes the energy-saving reconstruction of envelope structure and renewable energy sources into consideration.It plays a key role in analyzing the comprehensive efficiency and reasonable technology in the process of reconstruction.It is analyzed the technology of energy-saving reconstruction of wall for envelope structure,and put forward some measures in energy-saving reconstruction of existing residential buildings.
2009, 39(7): 7-9,19.
doi: 10.13204/j.gyjz200907003
Abstract:
With the accelerated development of urbanization process in our country,and the present situation of the high consumption of energy,and low level of energy-saving technologies in our country,as a result,the task of energy efficiency of buildings is very arduous.By analyzing the relationship between the energy efficiency of buildings and interior design,it is proposed that the main factors which have effects on the energy conservation of interior decoration,and makes a studied the method that how to save energy by combining modern technology with interior design,which can adapt to the ecological balance and harmony,and create a suitable indoor environment.It is also a new topic needing careful exploration by interior decoration and related industries.
With the accelerated development of urbanization process in our country,and the present situation of the high consumption of energy,and low level of energy-saving technologies in our country,as a result,the task of energy efficiency of buildings is very arduous.By analyzing the relationship between the energy efficiency of buildings and interior design,it is proposed that the main factors which have effects on the energy conservation of interior decoration,and makes a studied the method that how to save energy by combining modern technology with interior design,which can adapt to the ecological balance and harmony,and create a suitable indoor environment.It is also a new topic needing careful exploration by interior decoration and related industries.
2009, 39(7): 10-12.
doi: 10.13204/j.gyjz200907004
Abstract:
A solar energy rural residence is designed based on the analysis of plant greenhouse technology in rural area and aim to decrease the energy consumption on heating of rural residences in winter in the northern area of China.To a building,its roof is the largest area receiving solar energy,it has great influence on the amout of energy consumption.By modifying its tranditional form,a new one is designed with integrated solar panels to achieve a better natural lighting and collect more solar energy.Relying on the new roof system,energy saving and pollutant reduction will become the reality.
A solar energy rural residence is designed based on the analysis of plant greenhouse technology in rural area and aim to decrease the energy consumption on heating of rural residences in winter in the northern area of China.To a building,its roof is the largest area receiving solar energy,it has great influence on the amout of energy consumption.By modifying its tranditional form,a new one is designed with integrated solar panels to achieve a better natural lighting and collect more solar energy.Relying on the new roof system,energy saving and pollutant reduction will become the reality.
2009, 39(7): 13-15.
doi: 10.13204/j.gyjz200907005
Abstract:
It was analyzed that the general quality problems and structural defects of industrial buildings with colored steel sandwich panel;and it was also presented that the structure,technical innovations and examples of applied projects of energy-saving system of industrial buildings with HS-SSP colored steel sandwich panel.
It was analyzed that the general quality problems and structural defects of industrial buildings with colored steel sandwich panel;and it was also presented that the structure,technical innovations and examples of applied projects of energy-saving system of industrial buildings with HS-SSP colored steel sandwich panel.
2009, 39(7): 16-19.
doi: 10.13204/j.gyjz200907006
Abstract:
The chief measure for energy efficiency of a building is the heat preservation within the building,however,that external thermal insulation on system of organic material has some shortcomings at present,such as bad fireproofing,short lifetime and environmental pollution.Expanded and vitrified microball has some good performances because it is a inorganic material,and adapts to fature energy development trend.It is analyzed to foundation for designing energy efficiency in building to research the performances and application of heat preservation system of expanded and vitrified microball.
The chief measure for energy efficiency of a building is the heat preservation within the building,however,that external thermal insulation on system of organic material has some shortcomings at present,such as bad fireproofing,short lifetime and environmental pollution.Expanded and vitrified microball has some good performances because it is a inorganic material,and adapts to fature energy development trend.It is analyzed to foundation for designing energy efficiency in building to research the performances and application of heat preservation system of expanded and vitrified microball.
2009, 39(7): 20-22.
doi: 10.13204/j.gyjz200907007
Abstract:
It is introduced the methods of calculating energy consumption equilibrium of the buildings.Then it is also analyzed the energy-saving effect during use of a residential building to provide a quantitative assessment on energy conservation of buildings,which may provide main ways to save energy for buildings.
It is introduced the methods of calculating energy consumption equilibrium of the buildings.Then it is also analyzed the energy-saving effect during use of a residential building to provide a quantitative assessment on energy conservation of buildings,which may provide main ways to save energy for buildings.
2009, 39(7): 23-25,40.
doi: 10.13204/j.gyjz200907008
Abstract:
Analyzing the actuality of rural housings in the cold regions of China and considering all the factors including local economy,technology,productivity and eco-environment,etc,and from energy-saving and comfort point of view,it was presented that highly workable reform mesaures of rural housings in order to make northern rural housings be comfortable,healthy,energy efficient and environmental friendly.
Analyzing the actuality of rural housings in the cold regions of China and considering all the factors including local economy,technology,productivity and eco-environment,etc,and from energy-saving and comfort point of view,it was presented that highly workable reform mesaures of rural housings in order to make northern rural housings be comfortable,healthy,energy efficient and environmental friendly.
2009, 39(7): 26-28.
doi: 10.13204/j.gyjz200907009
Abstract:
Energy-Efficient Design of the Wall for a residential building has become a basic research on architectural sustainable development.It is studied the suitable energy efficiency technology of Building envelope,in view of the climate characteristics in Hunan area.
Energy-Efficient Design of the Wall for a residential building has become a basic research on architectural sustainable development.It is studied the suitable energy efficiency technology of Building envelope,in view of the climate characteristics in Hunan area.
2009, 39(7): 29-31.
doi: 10.13204/j.gyjz200907010
Abstract:
Because of indifferent concept of energy-saving,more energy consumption and poor living couditions in the rural areas of north Jiangsu Province,in order to meet the needs of sustainable development,the planning and design scheme of ecoenergy-saving new ruralities in north Jiangsu was studied by starting from the view of ecology and suitability,as well as combined with subjects,which provided experience for the future developing direction of new ruralities in north Jiangsu.
Because of indifferent concept of energy-saving,more energy consumption and poor living couditions in the rural areas of north Jiangsu Province,in order to meet the needs of sustainable development,the planning and design scheme of ecoenergy-saving new ruralities in north Jiangsu was studied by starting from the view of ecology and suitability,as well as combined with subjects,which provided experience for the future developing direction of new ruralities in north Jiangsu.
2009, 39(7): 32-36,31.
doi: 10.13204/j.gyjz200907011
Abstract:
Environment vibration caused by equipment of coal preparation plant is quite serious,typical equipments were selected due to real project and the vibration of soil layers and surrounding building were simulated by sub-structure method,the influence of different hardened ground modes on transportation and attenuation of vibration wave and that on human body were mainly examined.The research result shows that vibration screen caused a strong vibration and it can be felt obviously within 30 meter of the plant,for a hardened ground,the amplitude of the surface is reduced,but acceleration is increased and vibration level is boosted accordingly than the unhardened one.For an unhardened ground,the vibration grade is close to the requirements of criterion of environment vibration and the vibrations on the surrounding buildings were very distinct.
Environment vibration caused by equipment of coal preparation plant is quite serious,typical equipments were selected due to real project and the vibration of soil layers and surrounding building were simulated by sub-structure method,the influence of different hardened ground modes on transportation and attenuation of vibration wave and that on human body were mainly examined.The research result shows that vibration screen caused a strong vibration and it can be felt obviously within 30 meter of the plant,for a hardened ground,the amplitude of the surface is reduced,but acceleration is increased and vibration level is boosted accordingly than the unhardened one.For an unhardened ground,the vibration grade is close to the requirements of criterion of environment vibration and the vibrations on the surrounding buildings were very distinct.
2009, 39(7): 37-40.
doi: 10.13204/j.gyjz200907012
Abstract:
Based on anti-seismic mechenism of the mega-frame structure,multi-rib open-web frame structure system with embedded concrete frame units is put forward.Though analyzing the horizontal earthquake action of multi-rib open-web frame structure by ETABS program,it is calculated and compared the variation rules of several major structural dynamic properties according to the density of frame grid element.The result shows that multi-rib open-web frame elements improve lateral stiffness of frame,and it can solve the torsion problem,which caused by short of lateral stiffness of ordinary frame or elements' arrangement.Pushover analysis shows multi-rib open-web frame structure obeys the ductility failure mechanism: first frame unit,then outer frame,and the safety margin of structure has been raised under strong earthquake.
Based on anti-seismic mechenism of the mega-frame structure,multi-rib open-web frame structure system with embedded concrete frame units is put forward.Though analyzing the horizontal earthquake action of multi-rib open-web frame structure by ETABS program,it is calculated and compared the variation rules of several major structural dynamic properties according to the density of frame grid element.The result shows that multi-rib open-web frame elements improve lateral stiffness of frame,and it can solve the torsion problem,which caused by short of lateral stiffness of ordinary frame or elements' arrangement.Pushover analysis shows multi-rib open-web frame structure obeys the ductility failure mechanism: first frame unit,then outer frame,and the safety margin of structure has been raised under strong earthquake.
2009, 39(7): 41-43,102.
doi: 10.13204/j.gyjz200907013
Abstract:
Steel frame filled with reinforced concrete deep beam(RCDB) is a new kind of lateral resisting system for tall building structure.The programming ANSYS was used to analyze the hysteretic behavior of the reinforced concrete deep beam with different high-to-span ratio and thickness.The results indicate that the reinforced concrete deep beam with different geometric parameter filled in the frame can effectively affect the lateral resisting stiffness,ultimate bearing capacity,ductility and energy dissipation capacity of the frame structure and meet requirement of a wide range variation of the lateral stiffness of the structure.Based on comparison analysis of the hysteretic behavior of reinforced concrete deep beam with different geometric parameter,the value of high-to-span ratio 1.5 is suggested for the deep beam that can be used in the new structure,structural reinforcement as well.
Steel frame filled with reinforced concrete deep beam(RCDB) is a new kind of lateral resisting system for tall building structure.The programming ANSYS was used to analyze the hysteretic behavior of the reinforced concrete deep beam with different high-to-span ratio and thickness.The results indicate that the reinforced concrete deep beam with different geometric parameter filled in the frame can effectively affect the lateral resisting stiffness,ultimate bearing capacity,ductility and energy dissipation capacity of the frame structure and meet requirement of a wide range variation of the lateral stiffness of the structure.Based on comparison analysis of the hysteretic behavior of reinforced concrete deep beam with different geometric parameter,the value of high-to-span ratio 1.5 is suggested for the deep beam that can be used in the new structure,structural reinforcement as well.
2009, 39(7): 44-47,82.
doi: 10.13204/j.gyjz200907014
Abstract:
On the basis of test researching on four unbonded prestressed assembly specimens,it was used the tool of moment-curvature to analyse the performances on elastic and elastic-plastic phase of the four unbonded prestressed precast samples.It was gained the moment-curvature model of prestressed precast specimens,by which the validity of theoretical analysis was verified by comparing the test results.Computing programmed was made and the theoretical results showed a good agreement with those of the test.Which provided a reasonable and effective nonlinear moment-curvature model for studying the non-linear performance of prestressed precast structures under a big earthquake.
On the basis of test researching on four unbonded prestressed assembly specimens,it was used the tool of moment-curvature to analyse the performances on elastic and elastic-plastic phase of the four unbonded prestressed precast samples.It was gained the moment-curvature model of prestressed precast specimens,by which the validity of theoretical analysis was verified by comparing the test results.Computing programmed was made and the theoretical results showed a good agreement with those of the test.Which provided a reasonable and effective nonlinear moment-curvature model for studying the non-linear performance of prestressed precast structures under a big earthquake.
2009, 39(7): 48-51,86.
doi: 10.13204/j.gyjz200907015
Abstract:
N-type concrete masonry is a new type of small-size concrete block masonry by improving the block shape to realize fully aligned web-shells.And,N-type masonry could be built with straight joint.Based on 6 half-grouted specimens,the compressive behaviors of N-type masonry were investigated.Test results showed that the average compressive strength of half-grouted N-type masonry was about 30% higher than that of the common concrete masonry.The main reason for the strength rising was the full-alignment of web-shells in N-type concrete masonry prisms.And a formula of average compressive strength of half-grouted N-type masonry was given,whose result agreed well with the result of test.
N-type concrete masonry is a new type of small-size concrete block masonry by improving the block shape to realize fully aligned web-shells.And,N-type masonry could be built with straight joint.Based on 6 half-grouted specimens,the compressive behaviors of N-type masonry were investigated.Test results showed that the average compressive strength of half-grouted N-type masonry was about 30% higher than that of the common concrete masonry.The main reason for the strength rising was the full-alignment of web-shells in N-type concrete masonry prisms.And a formula of average compressive strength of half-grouted N-type masonry was given,whose result agreed well with the result of test.
2009, 39(7): 52-55.
doi: 10.13204/j.gyjz200907016
Abstract:
It is presented a new method to determine the tip bearing capacity characteristic value of large diameter belled pile on soft substratum according to the settlement.Compared to the presented methods,it is a converse procedure here.First of all,the additional stress corresponding to the settlements is calculated with the settlement formula of single-pile in the code.Then,the tip pressure is obtained by substituting the additional stress into the Mindlin solution for a circular uniform distributed load.At last,the tip bearing capacity is obtained.Those factors,such as the bottom diameter,pile length,thickness and physical and mechanical properties of the bearing layer and substratum,etc,which effect the tip bearing capacity of large diameter belled pile on soft substratum,were considered in this method.
It is presented a new method to determine the tip bearing capacity characteristic value of large diameter belled pile on soft substratum according to the settlement.Compared to the presented methods,it is a converse procedure here.First of all,the additional stress corresponding to the settlements is calculated with the settlement formula of single-pile in the code.Then,the tip pressure is obtained by substituting the additional stress into the Mindlin solution for a circular uniform distributed load.At last,the tip bearing capacity is obtained.Those factors,such as the bottom diameter,pile length,thickness and physical and mechanical properties of the bearing layer and substratum,etc,which effect the tip bearing capacity of large diameter belled pile on soft substratum,were considered in this method.
2009, 39(7): 56-60,73.
doi: 10.13204/j.gyjz200907017
Abstract:
Under the condition of progressive loading,considering a parabolic variation of the horizontal permeability of soil in the disturbed zone and the combination seepage along both radial direction and vertical direction in the surrounding soil,the governing equations for the consolidation of a composite foundation was derived and their solutions were obtained.On the basis of the solutions for the excess pore water pressures,the average degree of consolidation for the composite foundation was obtained.Then the consolidation behaviors of the composite foundation were analyzed and a comparison between the present solution and some previous solutions was made.The results show: the longer the loading period,the slower the rate of consolidation;the greater the disturbance effect,the slower the rate of consolidation;the rate of consolidation calculated by the present solution is more rapid than that by the previous solutions which assumed the horizontal permeability of soil in the disturbed zone was linearly changed or kept constant as a reduced value.
Under the condition of progressive loading,considering a parabolic variation of the horizontal permeability of soil in the disturbed zone and the combination seepage along both radial direction and vertical direction in the surrounding soil,the governing equations for the consolidation of a composite foundation was derived and their solutions were obtained.On the basis of the solutions for the excess pore water pressures,the average degree of consolidation for the composite foundation was obtained.Then the consolidation behaviors of the composite foundation were analyzed and a comparison between the present solution and some previous solutions was made.The results show: the longer the loading period,the slower the rate of consolidation;the greater the disturbance effect,the slower the rate of consolidation;the rate of consolidation calculated by the present solution is more rapid than that by the previous solutions which assumed the horizontal permeability of soil in the disturbed zone was linearly changed or kept constant as a reduced value.
2009, 39(7): 61-66.
doi: 10.13204/j.gyjz200907018
Abstract:
It is well-established that the shaft capacity of piles jacked-in increases with time.In clays,this behaviour arises predominantly from the dissipation of positive excess pore pressures.In sands,this increase in the absence of pore pressure dissipation can't be attributed to the aforementioned mechanisms.A series of triaxial strain-holding tests are conducted,and a hypothesis is proposed to explain pile set-up in sand that an increase in radial stress due to restrained creep dilation of the soil close to the pile shaft causes an increase in shaft resistance.
It is well-established that the shaft capacity of piles jacked-in increases with time.In clays,this behaviour arises predominantly from the dissipation of positive excess pore pressures.In sands,this increase in the absence of pore pressure dissipation can't be attributed to the aforementioned mechanisms.A series of triaxial strain-holding tests are conducted,and a hypothesis is proposed to explain pile set-up in sand that an increase in radial stress due to restrained creep dilation of the soil close to the pile shaft causes an increase in shaft resistance.
2009, 39(7): 67-69,15.
doi: 10.13204/j.gyjz200907019
Abstract:
The resistance to the penetration of chloride ions of cover concrete has a direct influence on the durability of reinforced concrete structures.In order to improve the resistance to the penetration of chloride ions of cover concrete many technologies were developed,such as controlled permeability formwork,water repellence agent and antirust coat etc.A nondestructive in-situ test method called PERMIT ion migration test and the application of controlled permeability formwork,water repellence agent and antirust coat in the construction of Qingdao bay bridge were introduced.The PERMIT ion migration test was used to estimate the effect of them.The experimental results show that the PERMIT ion migration test can be used to estimate the effect of different kind of improving technologies.The improving technologies all can improve the resistance to the penetration of chloride ions of cover concrete.The different types of controlled permeability formwork have different grades of effect.Water repellence agent and antirust coat are the bests.
The resistance to the penetration of chloride ions of cover concrete has a direct influence on the durability of reinforced concrete structures.In order to improve the resistance to the penetration of chloride ions of cover concrete many technologies were developed,such as controlled permeability formwork,water repellence agent and antirust coat etc.A nondestructive in-situ test method called PERMIT ion migration test and the application of controlled permeability formwork,water repellence agent and antirust coat in the construction of Qingdao bay bridge were introduced.The PERMIT ion migration test was used to estimate the effect of them.The experimental results show that the PERMIT ion migration test can be used to estimate the effect of different kind of improving technologies.The improving technologies all can improve the resistance to the penetration of chloride ions of cover concrete.The different types of controlled permeability formwork have different grades of effect.Water repellence agent and antirust coat are the bests.
2009, 39(7): 70-73.
doi: 10.13204/j.gyjz200907020
Abstract:
Flexural performance of RC beams reinforced by ferrocement was tested after different high temperature,and the influence law of the high temperature on flexural performance was analyzed.The results indicated that the reinforcement method of ferrocement could increase flexural rigidity of RC Beams,and it could decrease the deflection of midspan.The bearing capacity of reinforced RC beam decreased to some extent with the increasing of heating temperature;while the temperature was below 450 ℃,the bearing capacity of reinforced RC beams decreased by less than 5%.It indicated that RC beams reinforced by ferrocement had well flameresistant capacity.
Flexural performance of RC beams reinforced by ferrocement was tested after different high temperature,and the influence law of the high temperature on flexural performance was analyzed.The results indicated that the reinforcement method of ferrocement could increase flexural rigidity of RC Beams,and it could decrease the deflection of midspan.The bearing capacity of reinforced RC beam decreased to some extent with the increasing of heating temperature;while the temperature was below 450 ℃,the bearing capacity of reinforced RC beams decreased by less than 5%.It indicated that RC beams reinforced by ferrocement had well flameresistant capacity.
2009, 39(7): 74-78.
doi: 10.13204/j.gyjz200907021
Abstract:
The additive was applied to change the property of cement soil.When the cement soil was made,the additive materials such as the powdered silicon,natural powdered pumice,sodium salt and surface active agent were added into the cement clay.It was found that,through the experiment,these additives can effectively improve the mechanical property and increase the compressive strength and frost resistance property.The strength characteristic and effect of cement clay with added admixtures were studied by experiment in laboratory and outdoors.The research results will provide a foundation for applying powdered silicon etc in engineering practice.
The additive was applied to change the property of cement soil.When the cement soil was made,the additive materials such as the powdered silicon,natural powdered pumice,sodium salt and surface active agent were added into the cement clay.It was found that,through the experiment,these additives can effectively improve the mechanical property and increase the compressive strength and frost resistance property.The strength characteristic and effect of cement clay with added admixtures were studied by experiment in laboratory and outdoors.The research results will provide a foundation for applying powdered silicon etc in engineering practice.
2009, 39(7): 79-82.
doi: 10.13204/j.gyjz200907022
Abstract:
There is a very strict corresponding relation between infrared spectra and the structure of a matter,which may be used to study the change in chemical composition of asphalt during its use.It was analyzed that the ageing mechanism of asphalt and the inhibitation of epoxy resin on asphalt ageing through comparison of the spectra from host asphalt,aged asphalt and aged epoxy resin-modified asphalt.
There is a very strict corresponding relation between infrared spectra and the structure of a matter,which may be used to study the change in chemical composition of asphalt during its use.It was analyzed that the ageing mechanism of asphalt and the inhibitation of epoxy resin on asphalt ageing through comparison of the spectra from host asphalt,aged asphalt and aged epoxy resin-modified asphalt.
2009, 39(7): 83-86.
doi: 10.13204/j.gyjz200907023
Abstract:
In order to generalize HRB500 reinforcement and provide warrant for the redaction of Code for Design of Concrete Structures,the experiment researches should be done on the main characteristic of HRB500 reinforcement concrete members.The results of experimental study of 4 HRB500 reinforcement concrete columns under monotonous eccentric compression are summarized.Based on 4 tests,the typical features of deflection,the failing forms and the compressive behavior of columns are analyzed.It is shown that the failure shape,the pattern of deflection and the strain distribution of section of experimental columns are similar to the ordinary high strength concrete columns.The actual capacity of bearing of higher strength concrete columns are smaller than the result with formula.
In order to generalize HRB500 reinforcement and provide warrant for the redaction of Code for Design of Concrete Structures,the experiment researches should be done on the main characteristic of HRB500 reinforcement concrete members.The results of experimental study of 4 HRB500 reinforcement concrete columns under monotonous eccentric compression are summarized.Based on 4 tests,the typical features of deflection,the failing forms and the compressive behavior of columns are analyzed.It is shown that the failure shape,the pattern of deflection and the strain distribution of section of experimental columns are similar to the ordinary high strength concrete columns.The actual capacity of bearing of higher strength concrete columns are smaller than the result with formula.
2009, 39(7): 87-91.
doi: 10.13204/j.gyjz200907024
Abstract:
Based on some comparisons between the advantages and disadvantages of the two structural systems and the shaking table tests had verified that the preliminary design has a good seismic performance,the special concentrically braced steel frame with pinned connections was selected for the main building of a large thermal power plant.Taking the detailed design of this structure as prototype,the numerical analysis had been conducted.The results show that,this structure is the one with torsion and vertical mass irregularity,but considering that no members yield or out-of-plane buckling under frequent earthquakes,the inter-storey drift angles are all less than the limit values of the GB 500112001 under frequent and rare earthquakes,the detailed design is reasonable and it is predicted that the structure can meet the requirements of no damage under frequent earthquake and no-collapse under rare earthquake.The results of the present study once again show that if the design is reasonable,the special concentrically braced steel frame with pinned connections has a good seismic performance in the seismic region with aseismic fortification of intensity 8 and the building height of such a structure can exceed the required limitation height of a 12-story civil building.At last,some suggestions on the seismic design method of connections are proposed.
Based on some comparisons between the advantages and disadvantages of the two structural systems and the shaking table tests had verified that the preliminary design has a good seismic performance,the special concentrically braced steel frame with pinned connections was selected for the main building of a large thermal power plant.Taking the detailed design of this structure as prototype,the numerical analysis had been conducted.The results show that,this structure is the one with torsion and vertical mass irregularity,but considering that no members yield or out-of-plane buckling under frequent earthquakes,the inter-storey drift angles are all less than the limit values of the GB 500112001 under frequent and rare earthquakes,the detailed design is reasonable and it is predicted that the structure can meet the requirements of no damage under frequent earthquake and no-collapse under rare earthquake.The results of the present study once again show that if the design is reasonable,the special concentrically braced steel frame with pinned connections has a good seismic performance in the seismic region with aseismic fortification of intensity 8 and the building height of such a structure can exceed the required limitation height of a 12-story civil building.At last,some suggestions on the seismic design method of connections are proposed.
2009, 39(7): 92-94,91.
doi: 10.13204/j.gyjz200907025
Abstract:
Bending behavior of 24 G550 high strength cold-formed steel continuous hat section purlins with two-span are tested.The section forms are divided into two kinds: TS40 and TS61.Using finite strip method and direct strength method to calculate the ultimate bending resistance of these continuous purlins.The results calculated by formulas are close to those of the test.And then,the paper use finite element method is used to analyse the test specimens,the results are compared with the test.Comparison shows that the test results are higher than those calculated by direct strength method,the direct strength method for designing the high strength cold-formed steel continuous hat section purlin with two-span are safe,as reference for engineering design;the results of finite element method agree well with those of the test,so the finite element method can simulate the bending behavior of these purlins accurately.
Bending behavior of 24 G550 high strength cold-formed steel continuous hat section purlins with two-span are tested.The section forms are divided into two kinds: TS40 and TS61.Using finite strip method and direct strength method to calculate the ultimate bending resistance of these continuous purlins.The results calculated by formulas are close to those of the test.And then,the paper use finite element method is used to analyse the test specimens,the results are compared with the test.Comparison shows that the test results are higher than those calculated by direct strength method,the direct strength method for designing the high strength cold-formed steel continuous hat section purlin with two-span are safe,as reference for engineering design;the results of finite element method agree well with those of the test,so the finite element method can simulate the bending behavior of these purlins accurately.
2009, 39(7): 95-97.
doi: 10.13204/j.gyjz200907026
Abstract:
Based on unified strength theory and some essential suppositions,the ultimate bearing capacity formula of concentrically compressed stub columns reinforced by concrete filled circular CFRP-steel tube is deduced,considering the restriction of CFRP-steel tube to inner concrete and vertical bearing capacity of outer reinforced concrete.The results of the proposed formula are found in good agreement with experiment results.In the last,the effects of the total confinement factor,confinement factor of steel tube and confinement factor of CFRP on the ultimate bearing capacity are analyzed.
Based on unified strength theory and some essential suppositions,the ultimate bearing capacity formula of concentrically compressed stub columns reinforced by concrete filled circular CFRP-steel tube is deduced,considering the restriction of CFRP-steel tube to inner concrete and vertical bearing capacity of outer reinforced concrete.The results of the proposed formula are found in good agreement with experiment results.In the last,the effects of the total confinement factor,confinement factor of steel tube and confinement factor of CFRP on the ultimate bearing capacity are analyzed.
2009, 39(7): 98-102.
doi: 10.13204/j.gyjz200907027
Abstract:
In this paper,the maximum depth-to-thickness ratio of steel plate without local buckling is given,and an equation for the calculation of bearing capacity of composite sections with both stocky and slender steel elements has been proposed and validated against extensive experimental results available in the literatures.At the same time,the experimental results are compared with the results calculated according to CECS code,DBJ code,EC4 code,LFRD code and AIJ code,and among them the simplified method in this paper is best to calculate the bearing capacity of specimen.The simplified method can be used to calculate the bearing capacity of rectangular composite columns with thick or slender steel plate.
In this paper,the maximum depth-to-thickness ratio of steel plate without local buckling is given,and an equation for the calculation of bearing capacity of composite sections with both stocky and slender steel elements has been proposed and validated against extensive experimental results available in the literatures.At the same time,the experimental results are compared with the results calculated according to CECS code,DBJ code,EC4 code,LFRD code and AIJ code,and among them the simplified method in this paper is best to calculate the bearing capacity of specimen.The simplified method can be used to calculate the bearing capacity of rectangular composite columns with thick or slender steel plate.
2009, 39(7): 103-106.
doi: 10.13204/j.gyjz200907028
Abstract:
According to the full-range nonlinear dynamic response analysis method,dynamic stability of geodesic single layer reticulated shells under earthquake excitation is discussed systematically.Primary parameters are taken into account,such as combinations of vertical and horizontal earthquake action,material nonlinearities,rise to span ratios,initial geometric imperfection,cross-sectional areas of members,supporting condition,structure damp and different earthquake waves and so on.The results obtained in this paper can provide a valuable reference for practical design of reticulated shells.
According to the full-range nonlinear dynamic response analysis method,dynamic stability of geodesic single layer reticulated shells under earthquake excitation is discussed systematically.Primary parameters are taken into account,such as combinations of vertical and horizontal earthquake action,material nonlinearities,rise to span ratios,initial geometric imperfection,cross-sectional areas of members,supporting condition,structure damp and different earthquake waves and so on.The results obtained in this paper can provide a valuable reference for practical design of reticulated shells.
2009, 39(7): 107-110.
doi: 10.13204/j.gyjz200907029
Abstract:
To understand mechanical properties of circular steel tube composite columns filled with steel reinforced concrete under low frequency cyclic loading,five circular steel tube composite columns filled with steel reinforced concrete under horizontal low-cyclic loading are tested,whose results are analyzed.The looping curves and the skeleton curves under different axial compression ratios and different steel ratios are obtained,and it is compared the effects of different axial compression ratios and different steel ratios on bearing capacity of members.The results show that circular steel tube composite columns filled with steel reinforced concrete has a high bearing capacity,and a good capacity of energy dissipation.From the skeleton curve,it is found that with the increase of steel ratio,the bearing capacity and ductility of columns have been significantly improved;in addition,with increase in the axial compression ratio,ductility of the components is decreased and the lower the axial compression ratio,the better the ductility of the components.
To understand mechanical properties of circular steel tube composite columns filled with steel reinforced concrete under low frequency cyclic loading,five circular steel tube composite columns filled with steel reinforced concrete under horizontal low-cyclic loading are tested,whose results are analyzed.The looping curves and the skeleton curves under different axial compression ratios and different steel ratios are obtained,and it is compared the effects of different axial compression ratios and different steel ratios on bearing capacity of members.The results show that circular steel tube composite columns filled with steel reinforced concrete has a high bearing capacity,and a good capacity of energy dissipation.From the skeleton curve,it is found that with the increase of steel ratio,the bearing capacity and ductility of columns have been significantly improved;in addition,with increase in the axial compression ratio,ductility of the components is decreased and the lower the axial compression ratio,the better the ductility of the components.
2009, 39(7): 111-114,106.
doi: 10.13204/j.gyjz200907030
Abstract:
Based on the experiment of nine RC approximate full-size square columns,the impact on performance of axial compressive RC columns caused by drilled core with 100 mm diameter is studied.After drilling core on axial compressive RC columns,not only the load-bearing capacity has a 5.63%～22.14% decrease and the ultimate displacement has a(1.88%～)26.14% decrease,but also the failure mode will transfer from axial compression to small eccentricity compression.The experimental results are firstly described,then effective factors such as cross-section of column,position of core,filled the core with HSC,cut off of the reinforcement are studied,and mechanisms of these factors are also analyzed.
Based on the experiment of nine RC approximate full-size square columns,the impact on performance of axial compressive RC columns caused by drilled core with 100 mm diameter is studied.After drilling core on axial compressive RC columns,not only the load-bearing capacity has a 5.63%～22.14% decrease and the ultimate displacement has a(1.88%～)26.14% decrease,but also the failure mode will transfer from axial compression to small eccentricity compression.The experimental results are firstly described,then effective factors such as cross-section of column,position of core,filled the core with HSC,cut off of the reinforcement are studied,and mechanisms of these factors are also analyzed.
2009, 39(7): 115-117.
doi: 10.13204/j.gyjz200907031
Abstract:
Steel structures are often used in the reconstruction project of concrete structures.The connection between added steel girders and existing concrete structures are commonly encountered.The behavior of the connection affects the global working state of the joint and the stress status of added members.Finite element calculation and analysis were conducted in details on the connection joint in common use.The connection stiffness,deformation of steel anchoring plate,contact stress and the stress state of bonded rebar were analyzed and suggestions on application in projects were provided,which may be a important reference for similar projects.
Steel structures are often used in the reconstruction project of concrete structures.The connection between added steel girders and existing concrete structures are commonly encountered.The behavior of the connection affects the global working state of the joint and the stress status of added members.Finite element calculation and analysis were conducted in details on the connection joint in common use.The connection stiffness,deformation of steel anchoring plate,contact stress and the stress state of bonded rebar were analyzed and suggestions on application in projects were provided,which may be a important reference for similar projects.
2009, 39(7): 118-119,110.
doi: 10.13204/j.gyjz200907032
Abstract:
Based on the example of building safety apprasial in ground fissure zone,how to make safety appraisal for those buildings and which measures should be taken were studied.Which is useful for buildings of fissures zones in Xi'an and also provides experience for other regions suffering from ground fissure disasters.
Based on the example of building safety apprasial in ground fissure zone,how to make safety appraisal for those buildings and which measures should be taken were studied.Which is useful for buildings of fissures zones in Xi'an and also provides experience for other regions suffering from ground fissure disasters.
2009, 39(7): 120-123.
doi: 10.13204/j.gyjz200907033
Abstract:
In early March of 2007,the northeast region in China encountered an unusual snowstorm,which caused a large number of light-weight steel structure engineering accidents.It is necessary to summarize and intruspect.An overall analysis on a certain mill building of light-weight steel structure with portal frame.It is introduced the damage condition and appraisal result,and summarized the accident causes,moreover,it is also described the scheme of strengthening and rehabilitation.The paper comes to the conclusion that accumulated snow effect of parapet and southern attached building in North area and secondary disasters produced in the process of snow cleaning are the causes,so as to give suggestions on the current design of light-weight steel structures.
In early March of 2007,the northeast region in China encountered an unusual snowstorm,which caused a large number of light-weight steel structure engineering accidents.It is necessary to summarize and intruspect.An overall analysis on a certain mill building of light-weight steel structure with portal frame.It is introduced the damage condition and appraisal result,and summarized the accident causes,moreover,it is also described the scheme of strengthening and rehabilitation.The paper comes to the conclusion that accumulated snow effect of parapet and southern attached building in North area and secondary disasters produced in the process of snow cleaning are the causes,so as to give suggestions on the current design of light-weight steel structures.
