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2011 Vol. 41, No. 3
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2011, 41(3): 1-5,45.
doi: 10.13204/j.gyjz201103001
Abstract:
Structural insulated panels(SIPs) are structural sandwich panels consisting of a foam plastic insulation core securely bonded between two structural facings made of the wheat-rice straw particleboard or oriented strand board other than metal surfaces.They have good characteristics of energy conservation and environmental protection.The paper systematically analyzed the mechanical properties of SIPs by using vacuum equipment and gained their load-deflection curves under uniformly distributed load,which will provide a basis getting future theoretical equations.
Structural insulated panels(SIPs) are structural sandwich panels consisting of a foam plastic insulation core securely bonded between two structural facings made of the wheat-rice straw particleboard or oriented strand board other than metal surfaces.They have good characteristics of energy conservation and environmental protection.The paper systematically analyzed the mechanical properties of SIPs by using vacuum equipment and gained their load-deflection curves under uniformly distributed load,which will provide a basis getting future theoretical equations.
2011, 41(3): 6-8.
doi: 10.13204/j.gyjz201103002
Abstract:
Based on theoretical analysis,the paper gained the deflection calculating equation with considering the influence of the local stiffness of the faces.The FE simulation of SIPs was done using ABAQUS,It was compared the results by the equation,FE and tests.Finally,the deflection calculating equation was improved for the practical use.
Based on theoretical analysis,the paper gained the deflection calculating equation with considering the influence of the local stiffness of the faces.The FE simulation of SIPs was done using ABAQUS,It was compared the results by the equation,FE and tests.Finally,the deflection calculating equation was improved for the practical use.
2011, 41(3): 9-15.
doi: 10.13204/j.gyjz201103003
Abstract:
Metal surface sandwich,is a kind of popular building insulation material.Now the new national code only has the bending capacity equation for steel face,not for other faces.This paper completed 48 different kinds of face sandwich bending test including stainless steel panel,aluminum panel and straw panel and 27 core material tests and gained the mechanical characters and bending bearing capacity of these materials,which provided basis for deducing the unified formula of bending capacity.
Metal surface sandwich,is a kind of popular building insulation material.Now the new national code only has the bending capacity equation for steel face,not for other faces.This paper completed 48 different kinds of face sandwich bending test including stainless steel panel,aluminum panel and straw panel and 27 core material tests and gained the mechanical characters and bending bearing capacity of these materials,which provided basis for deducing the unified formula of bending capacity.
2011, 41(3): 23-28,51.
doi: 10.13204/j.gyjz201103004
Abstract:
Experimental investigation,energy balance and finite element method were developed in this paper to study the dynamic response of metallic sandwich panel subjected to blast loading.First,an experimental set-up which could investigate the dynamic response of sandwich panel under blast loading was presented.Then,the deflection equation of sandwich panel was obtained which was based on an energy balance and assumed deflection field.Finally,finite elements simulations were undertaken using the LS-DYNA software,such as deformation processes of the sandwich panel.Both models were validated by comparing their predictions with the test results available in the literature.Parametric studies were then carried out to assess various factors that are influential in charactering dynamic behavior of sandwich panels subjected to blast loads.The result shows that,for the purposes of improving the impact resistance of sandwich panel can be realized by the method of increasing density of the foam core,thickness of face-sheets and foam core.
Experimental investigation,energy balance and finite element method were developed in this paper to study the dynamic response of metallic sandwich panel subjected to blast loading.First,an experimental set-up which could investigate the dynamic response of sandwich panel under blast loading was presented.Then,the deflection equation of sandwich panel was obtained which was based on an energy balance and assumed deflection field.Finally,finite elements simulations were undertaken using the LS-DYNA software,such as deformation processes of the sandwich panel.Both models were validated by comparing their predictions with the test results available in the literature.Parametric studies were then carried out to assess various factors that are influential in charactering dynamic behavior of sandwich panels subjected to blast loads.The result shows that,for the purposes of improving the impact resistance of sandwich panel can be realized by the method of increasing density of the foam core,thickness of face-sheets and foam core.
2011, 41(3): 29-35.
doi: 10.13204/j.gyjz201103005
Abstract:
This paper studied the sandwich insulation performance under the fire through the finite element method and gained the fire ratines of rock wool and EPS core sandwich panels which agreed with the test results well.Finally,a new arrangement was proposed to improve the fire rating to satisfy the requirements of the current code.
This paper studied the sandwich insulation performance under the fire through the finite element method and gained the fire ratines of rock wool and EPS core sandwich panels which agreed with the test results well.Finally,a new arrangement was proposed to improve the fire rating to satisfy the requirements of the current code.
2011, 41(3): 36-41.
doi: 10.13204/j.gyjz201103006
Abstract:
The numerical simulation method is used to calculate the sound transmission loss of two different sandwiches with different thicknesses.Comparing with the experimental results,simulation results are proved to be correct.Then it is analysed the relationship among steel thickness,sandwiches thickness,sandwiches density and sound transmission loss.Setting the resonance frequency as the boundary,formula of sandwiches sound transmission loss is fitted.Error between experimental results and calculated results is small.The formula can direct engineering practice.
The numerical simulation method is used to calculate the sound transmission loss of two different sandwiches with different thicknesses.Comparing with the experimental results,simulation results are proved to be correct.Then it is analysed the relationship among steel thickness,sandwiches thickness,sandwiches density and sound transmission loss.Setting the resonance frequency as the boundary,formula of sandwiches sound transmission loss is fitted.Error between experimental results and calculated results is small.The formula can direct engineering practice.
2011, 41(3): 42-45.
doi: 10.13204/j.gyjz201103007
Abstract:
THEORY AND EXPERIMENT STUDY ON THE FATIGUE BEHAVIOR OF METAL SANDWICH PANEL
THEORY AND EXPERIMENT STUDY ON THE FATIGUE BEHAVIOR OF METAL SANDWICH PANEL
2011, 41(3): 46-51.
doi: 10.13204/j.gyjz201103008
Abstract:
As a kind of new-style building insulation material,sandwich panel is widely applied step by step in all kinds of industrial and civil architectures.In this paper,the ultrasonic non-destructive testing method was used to detect the possible damage of sandwich panel in normal use,and the wavelet analysis technique was used to precede a soft threshold de-noising treatment to the ultrasonic echo signal,then the de-noised ultrasonic echo signal was decomposed and the local modulus maxima of each layer was got.The results show that: after wavelet de-noising and wavelet decomposition,through identifying the arrival time of the reflected echo signal and the change of the various layerswaveform of the wavelet decomposition,the ultrasonic non-destructive testing method can effectively identify various types of damages.
As a kind of new-style building insulation material,sandwich panel is widely applied step by step in all kinds of industrial and civil architectures.In this paper,the ultrasonic non-destructive testing method was used to detect the possible damage of sandwich panel in normal use,and the wavelet analysis technique was used to precede a soft threshold de-noising treatment to the ultrasonic echo signal,then the de-noised ultrasonic echo signal was decomposed and the local modulus maxima of each layer was got.The results show that: after wavelet de-noising and wavelet decomposition,through identifying the arrival time of the reflected echo signal and the change of the various layerswaveform of the wavelet decomposition,the ultrasonic non-destructive testing method can effectively identify various types of damages.
2011, 41(3): 52-56.
doi: 10.13204/j.gyjz201103009
Abstract:
Tongzhou is an important industrial area that promoting the development of Beijing City,its industrial resources have meny-sided value.But with the quickening pace of Tongzhou new town construction,large numbers of industrial enterprises need to reconstruct or move.Only by investigating in detail the industrial resources,classifying them according to their value,and adopting various suitable modes of conservation and reuse,can the value of the industrial heritages be protected,and the development of the city be also promoted to take a road of sustainable and renewal development.
Tongzhou is an important industrial area that promoting the development of Beijing City,its industrial resources have meny-sided value.But with the quickening pace of Tongzhou new town construction,large numbers of industrial enterprises need to reconstruct or move.Only by investigating in detail the industrial resources,classifying them according to their value,and adopting various suitable modes of conservation and reuse,can the value of the industrial heritages be protected,and the development of the city be also promoted to take a road of sustainable and renewal development.
2011, 41(3): 59-59,80.
doi: 10.13204/j.gyjz201103010
Abstract:
On the basis of discussion of the content and value of industrial ruins protection,the paper analyszed the status of industrial ruins protection in Henan Province.Taking No.3 State-Owned Textile Factory for example,the situation of industrial ruins,estimates the value of protection and provides the relative protection programs were analyzed.By protection,the industrial ruins could also bring more benefit to society.The status and the relative methods of current industrial ruins protection in Henan Province were probed,which would bring more positive effects to the protection.
On the basis of discussion of the content and value of industrial ruins protection,the paper analyszed the status of industrial ruins protection in Henan Province.Taking No.3 State-Owned Textile Factory for example,the situation of industrial ruins,estimates the value of protection and provides the relative protection programs were analyzed.By protection,the industrial ruins could also bring more benefit to society.The status and the relative methods of current industrial ruins protection in Henan Province were probed,which would bring more positive effects to the protection.
2011, 41(3): 60-62.
doi: 10.13204/j.gyjz201103011
Abstract:
Facing the global environmental problems and the shortage of natural resources,the design methods of old buildings reuse need to be researched urgently.Design flaws often cause irreparable damage.howewve,the objectivity and scientificalness of design will be improved greatly if advanced science and technology as well as the relevant data provided by them can be used.Based on the reuse design of state key laboratories,this paper discusses the support of the computer simulation technology in architecture reuse design.
Facing the global environmental problems and the shortage of natural resources,the design methods of old buildings reuse need to be researched urgently.Design flaws often cause irreparable damage.howewve,the objectivity and scientificalness of design will be improved greatly if advanced science and technology as well as the relevant data provided by them can be used.Based on the reuse design of state key laboratories,this paper discusses the support of the computer simulation technology in architecture reuse design.
2011, 41(3): 63-67,98.
doi: 10.13204/j.gyjz201103012
Abstract:
Mega hybrid frame-corewall structure is a new type of structural system for super high-rise buildings,which consists of mega SRC frame,RC corewall,and outrigger trusses.The lateral stiffness and cooperative working performance of structure can be effectively improved by using methods as follows: increasing the stiffness of mega beams and outriggers,setting mega braces on the mega frame.The analysis results indicate that using these methods can improve the lateral stiffness and reduce the stiffness irregularity.The transmission efficiency of internal forces between the substructure and the main structure under vertical load can be improved by setting mega braces as well as increasing the stiffness of mega beams.The axial force of core wall can be reduced by increasing the stiffness of outrigger under vertical load,therefore,the earthquake-resistant capacity of core wall can be improved.The bottom shear force and moment of the mega frame under earthquake can be increased significantly by setting mega braces.
Mega hybrid frame-corewall structure is a new type of structural system for super high-rise buildings,which consists of mega SRC frame,RC corewall,and outrigger trusses.The lateral stiffness and cooperative working performance of structure can be effectively improved by using methods as follows: increasing the stiffness of mega beams and outriggers,setting mega braces on the mega frame.The analysis results indicate that using these methods can improve the lateral stiffness and reduce the stiffness irregularity.The transmission efficiency of internal forces between the substructure and the main structure under vertical load can be improved by setting mega braces as well as increasing the stiffness of mega beams.The axial force of core wall can be reduced by increasing the stiffness of outrigger under vertical load,therefore,the earthquake-resistant capacity of core wall can be improved.The bottom shear force and moment of the mega frame under earthquake can be increased significantly by setting mega braces.
2011, 41(3): 68-72,139.
doi: 10.13204/j.gyjz201103013
Abstract:
Clinker silo is an important component of cement production line.The security problems existed in the design of traditional clinker silo are analyzed,and a new clinker silo roof structure system without central support columns is put forward.The critical factors,temperature and dynamic action,for the design of the new roof structure system are analyzed.Some key design elements are analyzed and construction measures are listed.Economical efficiency is analyzed,and some notices on applying this structure system are listed too.
Clinker silo is an important component of cement production line.The security problems existed in the design of traditional clinker silo are analyzed,and a new clinker silo roof structure system without central support columns is put forward.The critical factors,temperature and dynamic action,for the design of the new roof structure system are analyzed.Some key design elements are analyzed and construction measures are listed.Economical efficiency is analyzed,and some notices on applying this structure system are listed too.
2011, 41(3): 73-75,120.
doi: 10.13204/j.gyjz201103014
Abstract:
Based on the limits of the internal forces destroyed the equilibrium condition,it is derived theoretic formula of axial compression ratio of L-shaped steel-concrete short-limb shear wall.The optimum cross-section of the project is calculated according to the specified reinforcement ratio etc in codes;it is also recommended the axial compression ratio limib in the current code for short-limb shear wall,T-shaped and I-shaped short-limb shear walls.
Based on the limits of the internal forces destroyed the equilibrium condition,it is derived theoretic formula of axial compression ratio of L-shaped steel-concrete short-limb shear wall.The optimum cross-section of the project is calculated according to the specified reinforcement ratio etc in codes;it is also recommended the axial compression ratio limib in the current code for short-limb shear wall,T-shaped and I-shaped short-limb shear walls.
2011, 41(3): 76-80.
doi: 10.13204/j.gyjz201103015
Abstract:
The compression experiments of 12 masonry specimens with 4 different grades of mortar strength were made,it was analyzed its failure behaviors,deformation and other characters.The results show that cracking load and failure load have certain regularities,there is an obvious relationship between the compression strength and mortar.A proposed formula of compression strength is given for the sandwich masonry through data regression analysis.By the experimental investigation of 2 sandwich walls under low cyclic lodging,the failure features and basic seismic behavior such as deformation behavior,strength,ductility relations of this kind of walls have been analyzed.And studies show that this walls seismic behavior is excellent.
The compression experiments of 12 masonry specimens with 4 different grades of mortar strength were made,it was analyzed its failure behaviors,deformation and other characters.The results show that cracking load and failure load have certain regularities,there is an obvious relationship between the compression strength and mortar.A proposed formula of compression strength is given for the sandwich masonry through data regression analysis.By the experimental investigation of 2 sandwich walls under low cyclic lodging,the failure features and basic seismic behavior such as deformation behavior,strength,ductility relations of this kind of walls have been analyzed.And studies show that this walls seismic behavior is excellent.
2011, 41(3): 81-85.
doi: 10.13204/j.gyjz201103016
Abstract:
Confined compressive and direct shear tests were conducted on cohesive soil samples of different saturation degree impacted by different energy.The relationships between the density,compression curve,compression modulus and strength parameters after impact and impact energy were investigated.
Confined compressive and direct shear tests were conducted on cohesive soil samples of different saturation degree impacted by different energy.The relationships between the density,compression curve,compression modulus and strength parameters after impact and impact energy were investigated.
2011, 41(3): 86-90.
doi: 10.13204/j.gyjz201103017
Abstract:
In this paper,frost heave tests using frost susceptible silty clay were carried out by 1-D frost heaving test system with different temperature amplitudes and time intervals in continuous-intermittent freezing mode.Freezing front,frost heave and temperature gradient were analyzed when frost depth reached in stable stage.The influences of temperature amplitudes and time intervals on frost heave were acquaired.The results show that,in different temperature amplitudes,the curves of freezing front and frost heave fluctuate periodically and the period is 240 min which is equal to time intervals.Frost heave is 3.38 mm and 2.55 mm in different temperature amplitudes.With the increase of temperature amplitudes,frost heave reduce 23.2% and 42.0% respectively than that in continuous freezing mode.In different time intervals,frost heave increase in the parabolic,step and broken line type.Frost heave is 2.82 mm,2.55 mm and 1.81 mm when time intervals are 2 h,4 h and 8 h respectively.It is clear that frost heave reduces with the increase of time intervals.However,if time intervals are longer than 8 h,segregation ice and frost heave decrease.In that case,the strength of frozen wall will decrease in artificial freezing project.
In this paper,frost heave tests using frost susceptible silty clay were carried out by 1-D frost heaving test system with different temperature amplitudes and time intervals in continuous-intermittent freezing mode.Freezing front,frost heave and temperature gradient were analyzed when frost depth reached in stable stage.The influences of temperature amplitudes and time intervals on frost heave were acquaired.The results show that,in different temperature amplitudes,the curves of freezing front and frost heave fluctuate periodically and the period is 240 min which is equal to time intervals.Frost heave is 3.38 mm and 2.55 mm in different temperature amplitudes.With the increase of temperature amplitudes,frost heave reduce 23.2% and 42.0% respectively than that in continuous freezing mode.In different time intervals,frost heave increase in the parabolic,step and broken line type.Frost heave is 2.82 mm,2.55 mm and 1.81 mm when time intervals are 2 h,4 h and 8 h respectively.It is clear that frost heave reduces with the increase of time intervals.However,if time intervals are longer than 8 h,segregation ice and frost heave decrease.In that case,the strength of frozen wall will decrease in artificial freezing project.
2011, 41(3): 91-98.
doi: 10.13204/j.gyjz201103018
Abstract:
The influence of cover height,face supporting pressure and penetration rate on shield tunneling-induced ground surface settlement was studied with three-dimensinal physical model test.The mechanism of shield tunneling-induced ground surface settlement was analyzed,the ground settlement curves in different conditions were obtained,the influence of cover depth,face supporting pressure and penetration rate of shield tunnel on the surface settlement were discussed,and a newly-modified tunneling-induced ground settlement calculation method was presented.It is revealed that the maximum surface settlement decreases and the transverse settlement trough is widened with the increase of cover height,while the surface settlement increases with the augment of the face supporting pressure.The surface settlement is hardly influenced by the shield penetration,but obviously influenced by boundary soil disturbance induced by shield tunneling.
The influence of cover height,face supporting pressure and penetration rate on shield tunneling-induced ground surface settlement was studied with three-dimensinal physical model test.The mechanism of shield tunneling-induced ground surface settlement was analyzed,the ground settlement curves in different conditions were obtained,the influence of cover depth,face supporting pressure and penetration rate of shield tunnel on the surface settlement were discussed,and a newly-modified tunneling-induced ground settlement calculation method was presented.It is revealed that the maximum surface settlement decreases and the transverse settlement trough is widened with the increase of cover height,while the surface settlement increases with the augment of the face supporting pressure.The surface settlement is hardly influenced by the shield penetration,but obviously influenced by boundary soil disturbance induced by shield tunneling.
2011, 41(3): 99-102,126.
doi: 10.13204/j.gyjz201103019
Abstract:
The construction process of a press-in pile may lead to adverse effects on surrouding civil works.The in-situ monitoring tests were carried out in a practical construction.It is found that the central uplift displacement of surrounding buildings is lager than both of ends.The horizontal displacement along the direction of pressing is lager than back surface.The surrouding buildings may slope to construction site by pile pressing-in machine.The excessive pore water pressure is dying out with the distance extending from the pressing-in pile,and the effective radius is about 15 meters.
The construction process of a press-in pile may lead to adverse effects on surrouding civil works.The in-situ monitoring tests were carried out in a practical construction.It is found that the central uplift displacement of surrounding buildings is lager than both of ends.The horizontal displacement along the direction of pressing is lager than back surface.The surrouding buildings may slope to construction site by pile pressing-in machine.The excessive pore water pressure is dying out with the distance extending from the pressing-in pile,and the effective radius is about 15 meters.
2011, 41(3): 103-107,112.
doi: 10.13204/j.gyjz201103020
Abstract:
To study the hybrid effect of hybrid fiber sheets and its constitutive relation,uniaxial tensile tests of 1CnB(1 layer of CFRP sheet hybrid with n layers of BFRP sheets) hybrid fibers sheets with different hybrid ratio and two mixed modes are studied in this paper.The results show that when the volume ratio of BFRP is low,its damage mode still manifests in the form of linear elastic.But with the improving of the BFRP /CFRP ratio,the rupture strain become higher and higher,constitutive curve begins to showyield point elongationand the phenomenon of multi-level rupture;failure process is more gentle and with a clear sign,showing a certain degree of ductility and the shortcoming of brittle fracture of single fiber is overcome.The hybrid mode also has impact on the fiber hybrid effect,and the sandwich mixed mode is better than the outer layer mixed mode.Based on the test results,a formula of hybrid effect factor is put forward by regression analysis.Formula of critical volume ratio is derived,and further the constitutive relation of hybrid fiber is proposed.
To study the hybrid effect of hybrid fiber sheets and its constitutive relation,uniaxial tensile tests of 1CnB(1 layer of CFRP sheet hybrid with n layers of BFRP sheets) hybrid fibers sheets with different hybrid ratio and two mixed modes are studied in this paper.The results show that when the volume ratio of BFRP is low,its damage mode still manifests in the form of linear elastic.But with the improving of the BFRP /CFRP ratio,the rupture strain become higher and higher,constitutive curve begins to showyield point elongationand the phenomenon of multi-level rupture;failure process is more gentle and with a clear sign,showing a certain degree of ductility and the shortcoming of brittle fracture of single fiber is overcome.The hybrid mode also has impact on the fiber hybrid effect,and the sandwich mixed mode is better than the outer layer mixed mode.Based on the test results,a formula of hybrid effect factor is put forward by regression analysis.Formula of critical volume ratio is derived,and further the constitutive relation of hybrid fiber is proposed.
2011, 41(3): 108-112.
doi: 10.13204/j.gyjz201103021
Abstract:
Prestressing CFRP technique is a new retrofit method which gained more and more attention in recent years,but there is little research on the secondary load behavior of flexual member strengthened using prestressed CFRP plate at home and abroad.In this paper 2 reinforced concrete beams,which have a length of 7.2 m,were retrofitted with non-prestressed CFRP and prestressed CFRP respectively,and then were tested to investigate their secondary load performance.Based on the experiment result,the comparison of behavior between beam with non-prestressed CFRP plate and beam strengthened using prestressed CFRP after pre-loading was conducted.Furthermore,the advantages of flexual stiffness,ductility and material strength ratio were obtained through analyzing.The experiment result indicated that although having been loaded to its steel yielding before being strengthened,the specimen with prestressed CFRP plate had a bearing capacity no less than that with non-prestressed CFRP plate.Despite the degradation of its section,the defletion of the secondary load specimen was almost the same as the control specimen,which showed that strengthening reinforced concrete beams pre-loaded severely using prestressed CFRP plate could recover their flexural stiffness significantly.
Prestressing CFRP technique is a new retrofit method which gained more and more attention in recent years,but there is little research on the secondary load behavior of flexual member strengthened using prestressed CFRP plate at home and abroad.In this paper 2 reinforced concrete beams,which have a length of 7.2 m,were retrofitted with non-prestressed CFRP and prestressed CFRP respectively,and then were tested to investigate their secondary load performance.Based on the experiment result,the comparison of behavior between beam with non-prestressed CFRP plate and beam strengthened using prestressed CFRP after pre-loading was conducted.Furthermore,the advantages of flexual stiffness,ductility and material strength ratio were obtained through analyzing.The experiment result indicated that although having been loaded to its steel yielding before being strengthened,the specimen with prestressed CFRP plate had a bearing capacity no less than that with non-prestressed CFRP plate.Despite the degradation of its section,the defletion of the secondary load specimen was almost the same as the control specimen,which showed that strengthening reinforced concrete beams pre-loaded severely using prestressed CFRP plate could recover their flexural stiffness significantly.
2011, 41(3): 113-115,134.
doi: 10.13204/j.gyjz201103022
Abstract:
Density is an important indicator with durability and impermeability of rock-fill concrete.In order to study the feasibility of density detection method.Rock-fill concrete was applied to the additional second-line project of Lan-Xin railway between Wuxi and Jinghe,and the related experiments and study on that field were taken.Four methods,such as density measurement analysis,borehole core samples and core assessment,ultrasonic testing method,embedded tube nondestructive testing method,were used in some experimental section to detect the density of rock-fill concrete.And through the comparative analysis of detection results,it was found that the embedded tube nondestructive testing method in which the infrared imaging technology was used could detect the dense situation of concrete veritably with the simple operation and cheap cost.
Density is an important indicator with durability and impermeability of rock-fill concrete.In order to study the feasibility of density detection method.Rock-fill concrete was applied to the additional second-line project of Lan-Xin railway between Wuxi and Jinghe,and the related experiments and study on that field were taken.Four methods,such as density measurement analysis,borehole core samples and core assessment,ultrasonic testing method,embedded tube nondestructive testing method,were used in some experimental section to detect the density of rock-fill concrete.And through the comparative analysis of detection results,it was found that the embedded tube nondestructive testing method in which the infrared imaging technology was used could detect the dense situation of concrete veritably with the simple operation and cheap cost.
2011, 41(3): 116-120.
doi: 10.13204/j.gyjz201103023
Abstract:
Since the occurrence of prestress technology,the application and development of this technology in the pure stone structure are blank at present.The scope of stone application is greatly extended when applying the prestress to stone members,and mechanical property of stone components can be obviously improved;the development of stone architecture would no longer confined with its own flaws.Not only the characteristics of natural stone material could be still developed,but also the tenon and mortise technology of traditional architectural structure could be passed on from one generation to another.In addition,stone structures have permanent preservation value and the artistry of architecture.Based on the test and theory analysis,the application of new technology made breakthroughs in scales of stone structure,and combined contemporary long-span pre-stressed technique with stone perfectly;meanwhile,the new technology filled in the gap in which granite stone material could not be used in the long-span stone sturcture,which provided a theoretical basis for design of long-span pure stone structures in future.
Since the occurrence of prestress technology,the application and development of this technology in the pure stone structure are blank at present.The scope of stone application is greatly extended when applying the prestress to stone members,and mechanical property of stone components can be obviously improved;the development of stone architecture would no longer confined with its own flaws.Not only the characteristics of natural stone material could be still developed,but also the tenon and mortise technology of traditional architectural structure could be passed on from one generation to another.In addition,stone structures have permanent preservation value and the artistry of architecture.Based on the test and theory analysis,the application of new technology made breakthroughs in scales of stone structure,and combined contemporary long-span pre-stressed technique with stone perfectly;meanwhile,the new technology filled in the gap in which granite stone material could not be used in the long-span stone sturcture,which provided a theoretical basis for design of long-span pure stone structures in future.
2011, 41(3): 121-126.
doi: 10.13204/j.gyjz201103024
Abstract:
Doule-Tee(DT) floor has an optimistic application prospect attribute to its mechanical characteristics and the merits of precast structures.The composition feature and design principles of DT floors,the design method of connections are introduced and the possible development trend is proposed to provide references for the understanding,design and further research of DT floors.
Doule-Tee(DT) floor has an optimistic application prospect attribute to its mechanical characteristics and the merits of precast structures.The composition feature and design principles of DT floors,the design method of connections are introduced and the possible development trend is proposed to provide references for the understanding,design and further research of DT floors.
2011, 41(3): 127-130,62.
doi: 10.13204/j.gyjz201103025
Abstract:
The structural damages,which result from the inadequate bearing capacity or the asymmetric support of foundation,are one of the crucial works in the conservation of historical masonry constructions.Firstly,the box girders are slowly and evenly jacked by the manual pipe jacking technique,and then casting the core beam to form a whole,so the construction is gradually situated on a traywith sufficient rigidity.Consequently,the structural damages caused by the inadequate bearing capacity or the asymmetric support of foundation are thoroughly treated.According to a practical engineering,the principle of the underpinning by manual pipe-jacking,the design of the box-section beam,the techniques of jacking are investigated in detail,and some suggestions and specific implementation measures are presented.
The structural damages,which result from the inadequate bearing capacity or the asymmetric support of foundation,are one of the crucial works in the conservation of historical masonry constructions.Firstly,the box girders are slowly and evenly jacked by the manual pipe jacking technique,and then casting the core beam to form a whole,so the construction is gradually situated on a traywith sufficient rigidity.Consequently,the structural damages caused by the inadequate bearing capacity or the asymmetric support of foundation are thoroughly treated.According to a practical engineering,the principle of the underpinning by manual pipe-jacking,the design of the box-section beam,the techniques of jacking are investigated in detail,and some suggestions and specific implementation measures are presented.
2011, 41(3): 131-134.
doi: 10.13204/j.gyjz201103026
Abstract:
In recent years,a lot of problems appeared in some steel structure engineerings and steel structure industry,such as :the strange structures,the complex constructions,the difficulty of manufacture erection,the waste of materials,the expensive investment and so forth.All of the basic reasons come from the strange conception and design.Hence,the correction of design conception,the mastery of advanced technique and the meticulous creation of designing will be the key to the sound and active development of the steel structure industry in China.
In recent years,a lot of problems appeared in some steel structure engineerings and steel structure industry,such as :the strange structures,the complex constructions,the difficulty of manufacture erection,the waste of materials,the expensive investment and so forth.All of the basic reasons come from the strange conception and design.Hence,the correction of design conception,the mastery of advanced technique and the meticulous creation of designing will be the key to the sound and active development of the steel structure industry in China.
2011, 41(3): 135-139.
doi: 10.13204/j.gyjz201103027
Abstract:
With the information collection and field investigation,this paper introduces the origin and typical cases of the ecovillage in Demark,analyzes the trends of the development changes and tries to discuss the role which ecovillage plays in the ecological transition of the whole housing department.Finally,it proposes a way in sustainable transition which makes a combination of the top-down central government strategy and bottom-up local grassroots experimental activity.
With the information collection and field investigation,this paper introduces the origin and typical cases of the ecovillage in Demark,analyzes the trends of the development changes and tries to discuss the role which ecovillage plays in the ecological transition of the whole housing department.Finally,it proposes a way in sustainable transition which makes a combination of the top-down central government strategy and bottom-up local grassroots experimental activity.
