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2005 Vol. 35, No. 5
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2005, 35(5): 1-4,23.
doi: 10.13204/j.gyjz200505001
Abstract:
A new type of relative rigidity expression of pile- raft foundation is proposed using pile- raft foundation's simplified analytic method with interaction taken into account, it is analyzed that the effect of pile-raft foundation's relative rigidity on settlement of the raft, internal forces and reaction distribution of pile head; the relationship between the relative rigidity and length/width ratio of the raft is also researched. A rational formula of the raft thickness is put forward according to giving full play to the bearing capacity of the piles. Finally the rationality of the formula and the feasibility of engineering use are verified by two examples.
A new type of relative rigidity expression of pile- raft foundation is proposed using pile- raft foundation's simplified analytic method with interaction taken into account, it is analyzed that the effect of pile-raft foundation's relative rigidity on settlement of the raft, internal forces and reaction distribution of pile head; the relationship between the relative rigidity and length/width ratio of the raft is also researched. A rational formula of the raft thickness is put forward according to giving full play to the bearing capacity of the piles. Finally the rationality of the formula and the feasibility of engineering use are verified by two examples.
2005, 35(5): 5-9,15.
doi: 10.13204/j.gyjz200505002
Abstract:
By finite element method, the distributions of additional stress of piled raft foundations in different raft rigidities are analyzed. The results show pile top reaction, pile tip resistance and additional stress of the substratum are greatly influenced by raft rigidities, especially in the rigid foundations. Combined the results by finite element analyzing and Geddes' stress formula calculating, the raft rigidities also impact the relationships between vertical additional stress and depth and stress'respondence depth.
By finite element method, the distributions of additional stress of piled raft foundations in different raft rigidities are analyzed. The results show pile top reaction, pile tip resistance and additional stress of the substratum are greatly influenced by raft rigidities, especially in the rigid foundations. Combined the results by finite element analyzing and Geddes' stress formula calculating, the raft rigidities also impact the relationships between vertical additional stress and depth and stress'respondence depth.
2005, 35(5): 10-15.
doi: 10.13204/j.gyjz200505003
Abstract:
Through analysis of field test results drawn from pile-raft foundation settlement and reaction force of Shaanxi Postal Telecommunication Net Centre Building,a three-dimensional finite element model of ultra-high tube-in-tube structure,pile-raft foundation and subsoil is established by use of large-scale finite element software ANSYS,elastoplastic constitutive relation and medium plate theory;and non-linear numerical interaction analysis of the three under vertical loadis also done.Observed data of foundation settlement,proportion of pile to soilshare,etc.correspond well with those of numerical analysis.Further,pile-raft foundation settlement,force receiving and proportion of pile-soil share of ultra-high building in loess area are discussed.The analysis results indicate:adoption of super-lengthy perfusion pile has remarkable effect to decrease settlement in loess area,tube structures contribution to foundation rigidity ranges about 8 floors,which can reduce foundation differential settlement,the internal force distribution of the raft is very complicated,which is closely related with such factors as superstructure forms,piling arrangement and so on,moreover,the curving moment at rafts cantilever end is awfully great.
Through analysis of field test results drawn from pile-raft foundation settlement and reaction force of Shaanxi Postal Telecommunication Net Centre Building,a three-dimensional finite element model of ultra-high tube-in-tube structure,pile-raft foundation and subsoil is established by use of large-scale finite element software ANSYS,elastoplastic constitutive relation and medium plate theory;and non-linear numerical interaction analysis of the three under vertical loadis also done.Observed data of foundation settlement,proportion of pile to soilshare,etc.correspond well with those of numerical analysis.Further,pile-raft foundation settlement,force receiving and proportion of pile-soil share of ultra-high building in loess area are discussed.The analysis results indicate:adoption of super-lengthy perfusion pile has remarkable effect to decrease settlement in loess area,tube structures contribution to foundation rigidity ranges about 8 floors,which can reduce foundation differential settlement,the internal force distribution of the raft is very complicated,which is closely related with such factors as superstructure forms,piling arrangement and so on,moreover,the curving moment at rafts cantilever end is awfully great.
2005, 35(5): 16-19.
doi: 10.13204/j.gyjz200505004
Abstract:
Considering the interaction among pile-support,piles and soil and the elastoplastic property of soil,pile-support system is researched by three-dimensional non-linear finite element method.The change of soil non-uniform settlement with increase of load,pile counterforce development and stress distributing in the pile-support and link beam are researched.The working behavior of pile-support system is defined.The secondary stress for the non-uniform settlement is further studied and the effect of the non-uniform settlement is got.It is pointed out the rational piles and the decreases of asymmetric settlement are the effective methods to reduce the secondary stress and the steel ratio of platform and avoid inconvenience of construction。
Considering the interaction among pile-support,piles and soil and the elastoplastic property of soil,pile-support system is researched by three-dimensional non-linear finite element method.The change of soil non-uniform settlement with increase of load,pile counterforce development and stress distributing in the pile-support and link beam are researched.The working behavior of pile-support system is defined.The secondary stress for the non-uniform settlement is further studied and the effect of the non-uniform settlement is got.It is pointed out the rational piles and the decreases of asymmetric settlement are the effective methods to reduce the secondary stress and the steel ratio of platform and avoid inconvenience of construction。
2005, 35(5): 20-23.
doi: 10.13204/j.gyjz200505005
Abstract:
With the increase of the amount of high-rise buildings,it is shown that introducing the soil nonlinear behavior into the foundation design is very important.In this paper,the nonlinear behavior of soil in loading state is described and analyzed.By which, a certain understanding of the failure process of a raft foundation is obtained.
With the increase of the amount of high-rise buildings,it is shown that introducing the soil nonlinear behavior into the foundation design is very important.In this paper,the nonlinear behavior of soil in loading state is described and analyzed.By which, a certain understanding of the failure process of a raft foundation is obtained.
2005, 35(5): 24-27.
doi: 10.13204/j.gyjz200505006
Abstract:
The working condition of a composite pile foundation under vertical and uniform loads is simulated by finite element method.With some experiment results and classical solution of Boussinesq,the behavior of distribution of additional stress and deformation in the composite pile foundation is concluded by comparing with the calculated results of common pile foundation.Biggish additional stress exits in the soil between the piles and the stress is distributed equally along the pile shaft.There is a certain compression in the soil between the piles,which must be considered in the composite pile foundation settlement calculation as well as that under the pile bottom.In the end,a simple calculated method is presented and also applied to projects.
The working condition of a composite pile foundation under vertical and uniform loads is simulated by finite element method.With some experiment results and classical solution of Boussinesq,the behavior of distribution of additional stress and deformation in the composite pile foundation is concluded by comparing with the calculated results of common pile foundation.Biggish additional stress exits in the soil between the piles and the stress is distributed equally along the pile shaft.There is a certain compression in the soil between the piles,which must be considered in the composite pile foundation settlement calculation as well as that under the pile bottom.In the end,a simple calculated method is presented and also applied to projects.
2005, 35(5): 28-32.
doi: 10.13204/j.gyjz200505007
Abstract:
In order to overcome the shortcomings of determining the raft thickness of a pile-raft foundation traditionally,a complete method of determining the thickness of a raft can be obtained by the following steps:It is proposed that a method in which the thickness of a raft can be determined first in accordance with the limit state of normal service and is then checked according to the limit state of bearing capacity,and the basic factors influencing the raft thickness in the two limit states are analyzed,the simplified formulas of estimating the raft thickness,external force and resistance of two-way shearing are given by combining the plate theory,coworking of the pile-raft foundation and superstructure,strut-and-tie theory of pile cap punching as well as project experience,the calculative examples and other methods to determine raft thickness are also discussed.
In order to overcome the shortcomings of determining the raft thickness of a pile-raft foundation traditionally,a complete method of determining the thickness of a raft can be obtained by the following steps:It is proposed that a method in which the thickness of a raft can be determined first in accordance with the limit state of normal service and is then checked according to the limit state of bearing capacity,and the basic factors influencing the raft thickness in the two limit states are analyzed,the simplified formulas of estimating the raft thickness,external force and resistance of two-way shearing are given by combining the plate theory,coworking of the pile-raft foundation and superstructure,strut-and-tie theory of pile cap punching as well as project experience,the calculative examples and other methods to determine raft thickness are also discussed.
2005, 35(5): 33-36.
doi: 10.13204/j.gyjz200505008
Abstract:
A rectangular element of thick-thin plate on elastic continuum considering both normal and tangential reactions is presented based on element of plane rectangle and plate.It can be used for superstructure-foundation-soil interaction analyses.By means of comparing this consequence with the one from thin plate-theory,the correction of the thick-thin plate-theory is concluded.
A rectangular element of thick-thin plate on elastic continuum considering both normal and tangential reactions is presented based on element of plane rectangle and plate.It can be used for superstructure-foundation-soil interaction analyses.By means of comparing this consequence with the one from thin plate-theory,the correction of the thick-thin plate-theory is concluded.
2005, 35(5): 37-40.
doi: 10.13204/j.gyjz200505009
Abstract:
The present status of constructing single family housings in towns of China and their problems are analyzed according to the practice of constructing test housings in towns. The applicable techniques for construction of settlements in towns are discussed, based on which the principles of architectural design and technical use of constructing town settlements are also discussed.
The present status of constructing single family housings in towns of China and their problems are analyzed according to the practice of constructing test housings in towns. The applicable techniques for construction of settlements in towns are discussed, based on which the principles of architectural design and technical use of constructing town settlements are also discussed.
2005, 35(5): 41-44.
doi: 10.13204/j.gyjz200505010
Abstract:
In the modern and contemporary architecture, industrial architecture holds important place throughout, its narrative design concept and the structural esthetics characteristic has an important influence on the modern architecture and architects. Examining the influential stages in the industrial architecture development, this paper discusses the effect of the western industry architecture on the modern architecture, the architects, the environment landscape as well as in cultural art, and their expression.
In the modern and contemporary architecture, industrial architecture holds important place throughout, its narrative design concept and the structural esthetics characteristic has an important influence on the modern architecture and architects. Examining the influential stages in the industrial architecture development, this paper discusses the effect of the western industry architecture on the modern architecture, the architects, the environment landscape as well as in cultural art, and their expression.
2005, 35(5): 45-46,71.
doi: 10.13204/j.gyjz200505011
Abstract:
It is explored that three radical problems which are the concept of ecological residential area, the definition of ecological residential area, and whether ecological residential area is a real pattern or an ideal objective of residential area. The views of the author are also proposed.
It is explored that three radical problems which are the concept of ecological residential area, the definition of ecological residential area, and whether ecological residential area is a real pattern or an ideal objective of residential area. The views of the author are also proposed.
2005, 35(5): 47-49.
doi: 10.13204/j.gyjz200505012
Abstract:
Traditional checking of building design will be changed by automatic checking technology for code of building design, from manpower to computer automatic execution. This change will not only speed the process of checking, help find flaws of design, save time, but also avoid the interference of man to achieve justice.
Traditional checking of building design will be changed by automatic checking technology for code of building design, from manpower to computer automatic execution. This change will not only speed the process of checking, help find flaws of design, save time, but also avoid the interference of man to achieve justice.
2005, 35(5): 50-53.
doi: 10.13204/j.gyjz200505013
Abstract:
The dynamic characteristics of earthquake and structure response can be reflected precisely by the theory of response spectrum. A dynamic can be changed into a static when the theory of response spectrum is used to do the aseismic design of a structure. However it is difficult to conduct the aseismic designs of modern and large complicated structures with long spans, and deal with non proportional damping etc. Using power spectrum based on pseudo excitation method can solve the above problems and save time. Meanwhile the computing errors can also be avoided during the process of solutions.
The dynamic characteristics of earthquake and structure response can be reflected precisely by the theory of response spectrum. A dynamic can be changed into a static when the theory of response spectrum is used to do the aseismic design of a structure. However it is difficult to conduct the aseismic designs of modern and large complicated structures with long spans, and deal with non proportional damping etc. Using power spectrum based on pseudo excitation method can solve the above problems and save time. Meanwhile the computing errors can also be avoided during the process of solutions.
2005, 35(5): 54-55,62.
doi: 10.13204/j.gyjz200505014
Abstract:
Hidden beam should be designed between columns for frame supported flat plate structure(FSFPS)according to the new codes and punching shear reinforcements are set to immprove the punching shear strength of the slab column connections. To study the calculative methods for the slab, the spot experiment of a pilot project is done. The test result shows that EFM(equivalent frame method) still is an effective method on studying slab of frame supported flat plate structure. Based on which some design proposals for the new system are put forward.
Hidden beam should be designed between columns for frame supported flat plate structure(FSFPS)according to the new codes and punching shear reinforcements are set to immprove the punching shear strength of the slab column connections. To study the calculative methods for the slab, the spot experiment of a pilot project is done. The test result shows that EFM(equivalent frame method) still is an effective method on studying slab of frame supported flat plate structure. Based on which some design proposals for the new system are put forward.
2005, 35(5): 56-59,84.
doi: 10.13204/j.gyjz200505015
Abstract:
By the popularization of structure calculating software, designers of nowadays only need to input necessary data to the computer and then get the final result of calculation and analysis. But calculating software itself is a `camera obscure' to most of the designers due to the fact that the total process of calculating and processing might be beyond monitoring and control. Structure designers must possess of realizing structure concept so as to comprehend the elementary hypothesis, calculating model and extent of application of the calculating software, therefore to make better control of strucure performance to ensure its safety, economical cost and rational quality.
By the popularization of structure calculating software, designers of nowadays only need to input necessary data to the computer and then get the final result of calculation and analysis. But calculating software itself is a `camera obscure' to most of the designers due to the fact that the total process of calculating and processing might be beyond monitoring and control. Structure designers must possess of realizing structure concept so as to comprehend the elementary hypothesis, calculating model and extent of application of the calculating software, therefore to make better control of strucure performance to ensure its safety, economical cost and rational quality.
2005, 35(5): 60-62.
doi: 10.13204/j.gyjz200505016
Abstract:
In the dwelling construction of a city, when meeting the ground under which there is a certain thickness of soft soil, it is a better choice to let a static bol-t pressing pile and foundation under wall work together in consideration of condition restriction of the building place and economic cost. Engineering practice shows that this method is very effect in controlling settlement of building and also an economic one.
In the dwelling construction of a city, when meeting the ground under which there is a certain thickness of soft soil, it is a better choice to let a static bol-t pressing pile and foundation under wall work together in consideration of condition restriction of the building place and economic cost. Engineering practice shows that this method is very effect in controlling settlement of building and also an economic one.
2005, 35(5): 63-67.
doi: 10.13204/j.gyjz200505017
Abstract:
The damage experiments of reinforced concrete samples under synergistic effects of cyclic freeze thaw, deicing salt attack, rebar corrosion and bending load were investigated using a comprehensive experimental method. Synergistic effects of these factors on the damage evolvement of the reinforced concrete was studied by measuring the change of dynamic modulus, rebar strain and concrete strain. Experimental results showed similar rule in damage evolvement,but different damage rate between the normal strength concrete (C45) and the high strength concrete (C70). The dynamic modulus of the reinforced concrete degraded with increasing effecting factors. Meanwhile, an interesting phenomenon is revealed that the amplitude of cyclic strains increase with the numbers of freeze thaw cycles within a fixed temperature difference.
The damage experiments of reinforced concrete samples under synergistic effects of cyclic freeze thaw, deicing salt attack, rebar corrosion and bending load were investigated using a comprehensive experimental method. Synergistic effects of these factors on the damage evolvement of the reinforced concrete was studied by measuring the change of dynamic modulus, rebar strain and concrete strain. Experimental results showed similar rule in damage evolvement,but different damage rate between the normal strength concrete (C45) and the high strength concrete (C70). The dynamic modulus of the reinforced concrete degraded with increasing effecting factors. Meanwhile, an interesting phenomenon is revealed that the amplitude of cyclic strains increase with the numbers of freeze thaw cycles within a fixed temperature difference.
2005, 35(5): 68-71.
doi: 10.13204/j.gyjz200505018
Abstract:
According to technical specisication for inspection of concrete compressive strength by rebound method, several problems are discussed in inspection of concrete compressive strength and those of inspective data analysis are discussed chiefly.
According to technical specisication for inspection of concrete compressive strength by rebound method, several problems are discussed in inspection of concrete compressive strength and those of inspective data analysis are discussed chiefly.
2005, 35(5): 72-74.
doi: 10.13204/j.gyjz200505019
Abstract:
Based on the fuzzy partition clustering, an evaluation method of components durability is proposed. According to the principle that the sum of squares of generalized Euclid distance of durability indexes between components and their clustering center should be the least, the durability fuzzy partition matrix is modified by use of iteration until the optimum result is obtained. The method proves to be correct. It avoids the irrationality in the conventional method and can be easily realized by programming.
Based on the fuzzy partition clustering, an evaluation method of components durability is proposed. According to the principle that the sum of squares of generalized Euclid distance of durability indexes between components and their clustering center should be the least, the durability fuzzy partition matrix is modified by use of iteration until the optimum result is obtained. The method proves to be correct. It avoids the irrationality in the conventional method and can be easily realized by programming.
2005, 35(5): 75-80,109.
doi: 10.13204/j.gyjz200505020
Abstract:
The methods of joint time frequency analysis have been widely applied in civil engineering due to its ability to provide local time frequency characteristics of signal and the ability to analyze nonstationary signal. Linear transform, bi linear transform and Hilbert Huang transform have been applied in the simulation of artificial seismic wave, dynamic analysis and estimation of the reliability of structures, parameters identification and damage detection in civil engineering. The existing problems are presented and the further research direction is discussed based on the summation of the application of the methods in civil engineering.
The methods of joint time frequency analysis have been widely applied in civil engineering due to its ability to provide local time frequency characteristics of signal and the ability to analyze nonstationary signal. Linear transform, bi linear transform and Hilbert Huang transform have been applied in the simulation of artificial seismic wave, dynamic analysis and estimation of the reliability of structures, parameters identification and damage detection in civil engineering. The existing problems are presented and the further research direction is discussed based on the summation of the application of the methods in civil engineering.
2005, 35(5): 81-84.
doi: 10.13204/j.gyjz200505021
Abstract:
Wind load is one of the major dynamic loads on structures. Especially for high and long span buildings, it must be considered in the design. This paper represents an overview of several computational aspects on the generation procedure of wind velocity, including auto regressive method, harmony superposition method, inverse Fourier transform method and wavelet methods, which is hopeful of some use to researchers as well as practitioners in wind dynamic analysis.
Wind load is one of the major dynamic loads on structures. Especially for high and long span buildings, it must be considered in the design. This paper represents an overview of several computational aspects on the generation procedure of wind velocity, including auto regressive method, harmony superposition method, inverse Fourier transform method and wavelet methods, which is hopeful of some use to researchers as well as practitioners in wind dynamic analysis.
2005, 35(5): 85-87.
doi: 10.13204/j.gyjz200505022
Abstract:
The knee bracing steel frame(KBF) is a new kind of energy dissipating frame,which combines excellent ductility and lateral stiffness.As the structural fuse of the frame,the knee element will yield firstly under major earthquake so that no damage occurs to the major structural members and the rehabilitation will then be easy.To help fully understand the relations between the seismic performance and the structural parameters,systematic elastoplastic analysis of the KBF structure was conducted using the finite element method(FEM).Finally,general design recommendations were made according to the results of the FEM analysis.
The knee bracing steel frame(KBF) is a new kind of energy dissipating frame,which combines excellent ductility and lateral stiffness.As the structural fuse of the frame,the knee element will yield firstly under major earthquake so that no damage occurs to the major structural members and the rehabilitation will then be easy.To help fully understand the relations between the seismic performance and the structural parameters,systematic elastoplastic analysis of the KBF structure was conducted using the finite element method(FEM).Finally,general design recommendations were made according to the results of the FEM analysis.
2005, 35(5): 88-91.
doi: 10.13204/j.gyjz200505023
Abstract:
Cylindrical latticed sheel structures are widely used in indoor coal storage yard of the power palnt.However,due to the rusty atmosphere and the gravity of the coal,the rusty and bending bars appeared in the use of the structures.If there are too many members have seriously rusted and bent,the safety of the structures will be greatly decreased and even be collapsed.Taking the example of a practical engineering,this paper studied the influence of imperfection to the strength and stability of structures and established a model for calculating the corrosion and bending of members.In the final,the paper introduced the method of calculating the bearing capacity of this kind of structures with a random imperfection model.
Cylindrical latticed sheel structures are widely used in indoor coal storage yard of the power palnt.However,due to the rusty atmosphere and the gravity of the coal,the rusty and bending bars appeared in the use of the structures.If there are too many members have seriously rusted and bent,the safety of the structures will be greatly decreased and even be collapsed.Taking the example of a practical engineering,this paper studied the influence of imperfection to the strength and stability of structures and established a model for calculating the corrosion and bending of members.In the final,the paper introduced the method of calculating the bearing capacity of this kind of structures with a random imperfection model.
2005, 35(5): 92-94.
doi: 10.13204/j.gyjz200505024
Abstract:
The arrangement form of prestressed cables and rational choice of prestress level in the novel structural form of prestressed latticed structures are very important.By comparing of different types of arrangement for prestressed cables of a typical prestressed latticed structure,a general arrangement rule for prestressed cables is presented,which could be used a reference in the designing of similar structures.
The arrangement form of prestressed cables and rational choice of prestress level in the novel structural form of prestressed latticed structures are very important.By comparing of different types of arrangement for prestressed cables of a typical prestressed latticed structure,a general arrangement rule for prestressed cables is presented,which could be used a reference in the designing of similar structures.
2005, 35(5): 95-97.
doi: 10.13204/j.gyjz200505025
Abstract:
The pseudo-excitation method is applied to the random seismic response analysis of long-span space latticed structures.The difference of the structure response is studied generally under multiple support excitation and simple support excitation from two aspects of the displacements response variance and acceleration power spectrum.Some important conclusions are gained.On the other hand,it shows the pseudo-excitation method is efficient and precise and is applicable to the random seismic response analysis of the complicated structure under multiple support excitation,such as long-span space latticed structure.
The pseudo-excitation method is applied to the random seismic response analysis of long-span space latticed structures.The difference of the structure response is studied generally under multiple support excitation and simple support excitation from two aspects of the displacements response variance and acceleration power spectrum.Some important conclusions are gained.On the other hand,it shows the pseudo-excitation method is efficient and precise and is applicable to the random seismic response analysis of the complicated structure under multiple support excitation,such as long-span space latticed structure.
2005, 35(5): 98-100.
doi: 10.13204/j.gyjz200505026
Abstract:
It is put forward that a new method of testing steel framework joints stiffness, deflection method.From the basic definition of the joints stiffness,it considers that the deflection of a certain point of the beam consists of two parts,one is produced by the beams ideal elastic bend,the other is produced by the deformation of joint field.By the deflection test,the deflection produced by the deformation of joint field can be gained,accordingly,the change in the included angle that the beam axis relative to the pole axis can be gained too.
It is put forward that a new method of testing steel framework joints stiffness, deflection method.From the basic definition of the joints stiffness,it considers that the deflection of a certain point of the beam consists of two parts,one is produced by the beams ideal elastic bend,the other is produced by the deformation of joint field.By the deflection test,the deflection produced by the deformation of joint field can be gained,accordingly,the change in the included angle that the beam axis relative to the pole axis can be gained too.
2005, 35(5): 101-104.
doi: 10.13204/j.gyjz200505027
Abstract:
Basing on the experiment of 23 prototype reinforced concrete columns under eccentric simple-loaded action,four influence factors on the strength capacity and ductility of the columns have been studied respectively,which are the CFRP bond manner,load eccentricity,concrete strength and the longitudinal reinforcement ratio of columns.The research is significant to the strengthening of the RC columns with CFRP sheets.
Basing on the experiment of 23 prototype reinforced concrete columns under eccentric simple-loaded action,four influence factors on the strength capacity and ductility of the columns have been studied respectively,which are the CFRP bond manner,load eccentricity,concrete strength and the longitudinal reinforcement ratio of columns.The research is significant to the strengthening of the RC columns with CFRP sheets.
2005, 35(5): 105-106.
doi: 10.13204/j.gyjz200505028
Abstract:
The treatment scheme of strengthening the mill building was proposed through the analysis of the damages to the concrete structure by chlorides,by which the strengthening of the mill building was completed,which provided useful experience for the design and construction of similar projects.
The treatment scheme of strengthening the mill building was proposed through the analysis of the damages to the concrete structure by chlorides,by which the strengthening of the mill building was completed,which provided useful experience for the design and construction of similar projects.
CAUSE ANALYSIS AND PRECAUTIONS OF ACCIDENTS OF SCAFFOLD AND FORMWORK DURING CONSTRUCTION OF PROJECTS
2005, 35(5): 107-109.
doi: 10.13204/j.gyjz200505029
Abstract:
Combining with safety troubles of scaffold and formwork in constructions,the author describes the reasons of collapse of scaffold and formwork,and puts forward corresponding precautions in order to work safely.
Combining with safety troubles of scaffold and formwork in constructions,the author describes the reasons of collapse of scaffold and formwork,and puts forward corresponding precautions in order to work safely.
