Login
Register
E-alert
2007 Vol. 37, No. 9
Display Method:
2007, 37(9): 1-8.
doi: 10.13204/j.gyjz200709001
Abstract:
The construction mechanic combines structure mechanic and constructiontechnology together. Its main feature isthat the geometry profiles, the physical properties and the boundary conditions of a research object will change withconstruction duration. It is evident that the different construction processes and procedures will lead to different deformationand internal force distribution locked within a structure after the construction is ended. Therefore a structural design statemust be estimated accurately if a construction finished structure meetsthe design andservice requirements. Itwillbe focusedon the construction mechanic problems which are explored from many large and complex steel structure construction anderection processes currently. The ten key construction mechanic problems have been pointed out, and they are analyzed anddiscussed comprehensively. The discussion on these problems has of great importance to further developing constructionmechanics and engineering application.
The construction mechanic combines structure mechanic and constructiontechnology together. Its main feature isthat the geometry profiles, the physical properties and the boundary conditions of a research object will change withconstruction duration. It is evident that the different construction processes and procedures will lead to different deformationand internal force distribution locked within a structure after the construction is ended. Therefore a structural design statemust be estimated accurately if a construction finished structure meetsthe design andservice requirements. Itwillbe focusedon the construction mechanic problems which are explored from many large and complex steel structure construction anderection processes currently. The ten key construction mechanic problems have been pointed out, and they are analyzed anddiscussed comprehensively. The discussion on these problems has of great importance to further developing constructionmechanics and engineering application.
2007, 37(9): 9-15.
doi: 10.13204/j.gyjz200709002
Abstract:
If the structural members are fabricated and erected according to the structural design configuration (SDC)during the construction process of steel structures, it may lead to a considerable deviation between the structuralconstruction completed configuration and the SDC. Therefore it is necessary to take pre-set deformation values (PDV) forthe structural members during the construction process. It will be focused on three computational procedures for determiningpre-set deformation values of the structural members, namely, forward iteration method, backward iteration method andstepped comprehensive iteration method. Their advantages and disadvantages are pointed out where different constructionapproaches are employed. Numerical studies and engineering applications are given for different structural forms.
If the structural members are fabricated and erected according to the structural design configuration (SDC)during the construction process of steel structures, it may lead to a considerable deviation between the structuralconstruction completed configuration and the SDC. Therefore it is necessary to take pre-set deformation values (PDV) forthe structural members during the construction process. It will be focused on three computational procedures for determiningpre-set deformation values of the structural members, namely, forward iteration method, backward iteration method andstepped comprehensive iteration method. Their advantages and disadvantages are pointed out where different constructionapproaches are employed. Numerical studies and engineering applications are given for different structural forms.
2007, 37(9): 16-21.
doi: 10.13204/j.gyjz200709003
Abstract:
The new CCTV headquarters consists of two towers leaning 6 off vertical in both directions, a tremendous 14 -story -high cantilever joining two leaning towers at the top and a 9 -story -high podium at the bottom. Due to the continuouslyadded gravity and additional bending moment conducted during the construction process, the variation of the structuraldeformation is very complicated. During the construction process of the structure, it may lead to a considerable deviationbetween the structural construction -completed configuration and the structural design configurationwithout taking the pre -setdeformation value (PDV) for the structural members. It will be presented a computational method to determine PDVs forthese inclined high -rise structures, i. e. stepped comprehensive iteration method. This analysismethod has been conductedand directly applied in the determination of PDVs of structural members of the new CCTV headquarters. Lots of numericalresults have been obtained and used as guidelines for the erection and construction of the new CCTV headquarters.
The new CCTV headquarters consists of two towers leaning 6 off vertical in both directions, a tremendous 14 -story -high cantilever joining two leaning towers at the top and a 9 -story -high podium at the bottom. Due to the continuouslyadded gravity and additional bending moment conducted during the construction process, the variation of the structuraldeformation is very complicated. During the construction process of the structure, it may lead to a considerable deviationbetween the structural construction -completed configuration and the structural design configurationwithout taking the pre -setdeformation value (PDV) for the structural members. It will be presented a computational method to determine PDVs forthese inclined high -rise structures, i. e. stepped comprehensive iteration method. This analysismethod has been conductedand directly applied in the determination of PDVs of structural members of the new CCTV headquarters. Lots of numericalresults have been obtained and used as guidelines for the erection and construction of the new CCTV headquarters.
2007, 37(9): 22-29.
doi: 10.13204/j.gyjz200709004
Abstract:
The new CCTV headquarters consists of two towers leaning 6 -off vertical in both directions, a tremendous 14 -story -high cantilever joining two leaning towers at the top and a 9 -story -high podium at the bottom. Different constructionprocedures will lead to different internal force and deformation distribution during the construction process in this complexsteel structure. They will be locked within the structure and have to be considered in the structural design. It is evident thatthere is a great difference in internal force and deformation distribution between according to design model one time loadingand according to step -by -step construction process. And it is necessary to take reasonable construction procedures andmeasuresto guarantee the internal force and deformation of the construction -completed structure to meet the requirementgiven by designers. It is presented the internal force and deformation analysis of the CCTV new headquarters during theconstruction process by employing nonlinear finite element method, and the internal force anddeformationdistribution lockedin the structure is determined. Lots of numerical results have beenobtained asguidelinesfor the erection and construction ofthe project.
The new CCTV headquarters consists of two towers leaning 6 -off vertical in both directions, a tremendous 14 -story -high cantilever joining two leaning towers at the top and a 9 -story -high podium at the bottom. Different constructionprocedures will lead to different internal force and deformation distribution during the construction process in this complexsteel structure. They will be locked within the structure and have to be considered in the structural design. It is evident thatthere is a great difference in internal force and deformation distribution between according to design model one time loadingand according to step -by -step construction process. And it is necessary to take reasonable construction procedures andmeasuresto guarantee the internal force and deformation of the construction -completed structure to meet the requirementgiven by designers. It is presented the internal force and deformation analysis of the CCTV new headquarters during theconstruction process by employing nonlinear finite element method, and the internal force anddeformationdistribution lockedin the structure is determined. Lots of numerical results have beenobtained asguidelinesfor the erection and construction ofthe project.
2007, 37(9): 30-34,108.
doi: 10.13204/j.gyjz200709005
Abstract:
For the new CCTV headquarters, the deformation produced due to not only the loading affection resulting from itsinclined towers and cantilevered structure system but also the foundation settlement must be estimated to determine itsconstruction and erection procedure. It is focused on the integrative modeling analysis which includes the influence offoundation settlement and the interaction of pile group. Besides, the deformations calculated from FE model and measuredfrom actual project are compared, which shows that this analysis method can simulate the actual condition quite well.
For the new CCTV headquarters, the deformation produced due to not only the loading affection resulting from itsinclined towers and cantilevered structure system but also the foundation settlement must be estimated to determine itsconstruction and erection procedure. It is focused on the integrative modeling analysis which includes the influence offoundation settlement and the interaction of pile group. Besides, the deformations calculated from FE model and measuredfrom actual project are compared, which shows that this analysis method can simulate the actual condition quite well.
2007, 37(9): 35-40,15.
doi: 10.13204/j.gyjz200709006
Abstract:
The whole lift design and analysis of steel roof in A380 air craft hangar are presented. Some key mechanicalproblems are outlined and analyzed. To solve these problems, a hoisting process analysis procedure based on an integratedmodel is proposed. In this model, the interaction of a lifting steel roof, the latticed towers and the cables are consideredautomatically, as well as the influences of wind loads and temperature change are involved in the analysis. The continuouschecking of the deformation and stress distribution during hoisting process in A380air craft hangar are monitored and traced,and some important references are given as the guidelines of the lifting construction.
The whole lift design and analysis of steel roof in A380 air craft hangar are presented. Some key mechanicalproblems are outlined and analyzed. To solve these problems, a hoisting process analysis procedure based on an integratedmodel is proposed. In this model, the interaction of a lifting steel roof, the latticed towers and the cables are consideredautomatically, as well as the influences of wind loads and temperature change are involved in the analysis. The continuouschecking of the deformation and stress distribution during hoisting process in A380air craft hangar are monitored and traced,and some important references are given as the guidelines of the lifting construction.
2007, 37(9): 41-44.
doi: 10.13204/j.gyjz200709007
Abstract:
The erection technologies of large span chord -tension truss structure for Harbin International Exhibition Centerare introduced. Which include the organization of construction, the splicing and erectiontechnology of large span andweightchord -tension truss, the sliding technology of truss in different bearing level, the tension and analysis technology of prestresscable, the application of cast steel products etc, which provides experience for erection of steel structures in the future.
The erection technologies of large span chord -tension truss structure for Harbin International Exhibition Centerare introduced. Which include the organization of construction, the splicing and erectiontechnology of large span andweightchord -tension truss, the sliding technology of truss in different bearing level, the tension and analysis technology of prestresscable, the application of cast steel products etc, which provides experience for erection of steel structures in the future.
2007, 37(9): 45-47.
doi: 10.13204/j.gyjz200709008
Abstract:
The contradiction between the diversification and standardization of houses has been solved to a large extent bythe development of member standardization in Japan, which raises the industrial level of house industry.By the research onthe development of house parts in Japan, the aim, mode and problem analysis of house parts at each developing stage, it isdefined the role of such development and is also analyzed the effect of the rapid development of house memberstandardization on design.
The contradiction between the diversification and standardization of houses has been solved to a large extent bythe development of member standardization in Japan, which raises the industrial level of house industry.By the research onthe development of house parts in Japan, the aim, mode and problem analysis of house parts at each developing stage, it isdefined the role of such development and is also analyzed the effect of the rapid development of house memberstandardization on design.
2007, 37(9): 48-50,72.
doi: 10.13204/j.gyjz200709009
Abstract:
It is analyzed the design countermeasures for diversified demands on house design in Japan, which provesthat thesupport infill house is an effective means to realize diversifiedhouses; it is also definedthe demarcationbetween support infilland infill of a house through the analysis of NEXT21---a typical case of the support infillhouse. Thus clarifying the designproblems and subjects of house support infill.
It is analyzed the design countermeasures for diversified demands on house design in Japan, which provesthat thesupport infill house is an effective means to realize diversifiedhouses; it is also definedthe demarcationbetween support infilland infill of a house through the analysis of NEXT21---a typical case of the support infillhouse. Thus clarifying the designproblems and subjects of house support infill.
2007, 37(9): 51-54.
doi: 10.13204/j.gyjz200709010
Abstract:
The protecting andreuse of the industrial building heritage are concerned by more andmore people. As a famoushistoric city, there are large quantities of industrial building heritages in Shenyang, and these precious heritages are beingdestroyed. It is necessary to rescue these industrial building heritages. The general situation and character of industrialbuilding heritages are analyzed, andspecitic measures are brought up to protect and reuse of the industrial building heritagesin Shenyang. It is hopeful to encourage people to protect the industrial building heritages, reference and revelation will beprovided for the protecting and reuse of the industrial building heritages in Shenyang and up to the whole country.
The protecting andreuse of the industrial building heritage are concerned by more andmore people. As a famoushistoric city, there are large quantities of industrial building heritages in Shenyang, and these precious heritages are beingdestroyed. It is necessary to rescue these industrial building heritages. The general situation and character of industrialbuilding heritages are analyzed, andspecitic measures are brought up to protect and reuse of the industrial building heritagesin Shenyang. It is hopeful to encourage people to protect the industrial building heritages, reference and revelation will beprovided for the protecting and reuse of the industrial building heritages in Shenyang and up to the whole country.
2007, 37(9): 55-56,61.
doi: 10.13204/j.gyjz200709011
Abstract:
It is explored that the effects of the internal natural key element of base enviornmental characteristics and therestrained key element of peripheral environment on the design of buildings, via the creation of comprehensive buildings forgraduate students in new campus ofHenan University.
It is explored that the effects of the internal natural key element of base enviornmental characteristics and therestrained key element of peripheral environment on the design of buildings, via the creation of comprehensive buildings forgraduate students in new campus ofHenan University.
2007, 37(9): 57-61.
doi: 10.13204/j.gyjz200709012
Abstract:
Using the contrast tests of 13 recycled aggregate concrete beams and natural aggregate concrete beams, theeffects of replacement ratio of recycled coarse aggregate and shear -span ratio on the characters of shear capacity anddeformability of recycled concrete beams are investigated. The test result shows the deflection and diagonal crack of recycledaggregate concrete beams are bigger than natural aggregate concrete beams, the shear capacity of recycled concrete beamsreduceswith the increase of recycled coarse aggregate content, the shear capacity reduces with the increase of shear -spanratio. Based onthe result offailure by shear of recycled concrete beams andusing the ultimate equilibrium theory, a formulafor the shear strength of recycled concrete beams is recommended.
Using the contrast tests of 13 recycled aggregate concrete beams and natural aggregate concrete beams, theeffects of replacement ratio of recycled coarse aggregate and shear -span ratio on the characters of shear capacity anddeformability of recycled concrete beams are investigated. The test result shows the deflection and diagonal crack of recycledaggregate concrete beams are bigger than natural aggregate concrete beams, the shear capacity of recycled concrete beamsreduceswith the increase of recycled coarse aggregate content, the shear capacity reduces with the increase of shear -spanratio. Based onthe result offailure by shear of recycled concrete beams andusing the ultimate equilibrium theory, a formulafor the shear strength of recycled concrete beams is recommended.
2007, 37(9): 62-65.
doi: 10.13204/j.gyjz200709013
Abstract:
The experimental modal analysis has been adopted in Shanghai Kewei Building which is an ultra -code high -risebuilding. This paper introduces the designed engineering project as a special case to find the critical path method anddiscusses the main features in the anti-seismic design model.Analysis of the tested data and calculated data by finiteelement software are decided to find the reasonable errors and the experience from this project can be used for reference.
The experimental modal analysis has been adopted in Shanghai Kewei Building which is an ultra -code high -risebuilding. This paper introduces the designed engineering project as a special case to find the critical path method anddiscusses the main features in the anti-seismic design model.Analysis of the tested data and calculated data by finiteelement software are decided to find the reasonable errors and the experience from this project can be used for reference.
2007, 37(9): 66-68.
doi: 10.13204/j.gyjz200709014
Abstract:
The analogical ratio between scale models with less ballast andtheir prototypes are provided by the dimensionalanalysis. The analysis results of one 1/28 scale model and a 1/3.0 scale model of RC shear wall are given in order to verifythe correctness of the suggested analogical ratio in the paper, then the difference and modification of some parameters arediscussed.
The analogical ratio between scale models with less ballast andtheir prototypes are provided by the dimensionalanalysis. The analysis results of one 1/28 scale model and a 1/3.0 scale model of RC shear wall are given in order to verifythe correctness of the suggested analogical ratio in the paper, then the difference and modification of some parameters arediscussed.
2007, 37(9): 69-72.
doi: 10.13204/j.gyjz200709015
Abstract:
A new energy -saving composite wall structure is a new residential building structure characterized by low weight,energy-saving and good aseismic performance, which is mainly constructed with pre -cast multi-ribbed composite slabs,concealed frame and floor by means of assembling and casting.On the basis of previous study, the load -bearingcharacteristics of the wall are analyzed; heat transfer and thermal-insulating mechanism of the exterior slab are studied; localthermal bridge disposal and integral thermal -insulating disposal of the exterior slab are put forward;and finally, thehorizontal and vertical links of the slabs in the structure are discussed.
A new energy -saving composite wall structure is a new residential building structure characterized by low weight,energy-saving and good aseismic performance, which is mainly constructed with pre -cast multi-ribbed composite slabs,concealed frame and floor by means of assembling and casting.On the basis of previous study, the load -bearingcharacteristics of the wall are analyzed; heat transfer and thermal-insulating mechanism of the exterior slab are studied; localthermal bridge disposal and integral thermal -insulating disposal of the exterior slab are put forward;and finally, thehorizontal and vertical links of the slabs in the structure are discussed.
2007, 37(9): 73-76.
doi: 10.13204/j.gyjz200709016
Abstract:
Restoring force model plays a very important role in the research of earthquake -resistant structure. Taking thedeformation and internal force of a section as generalized stress -strain, utilizing plastic potential theory and flow rule as wellas hardening model and concrete yield criterion, it is induced the relation between force and deformation of frame columns(the skeleton curve of restoring force model). The choice of equation parameters and their identification are discussedaccording to the building code, and it is proved that the model agrees with the test resultswell.
Restoring force model plays a very important role in the research of earthquake -resistant structure. Taking thedeformation and internal force of a section as generalized stress -strain, utilizing plastic potential theory and flow rule as wellas hardening model and concrete yield criterion, it is induced the relation between force and deformation of frame columns(the skeleton curve of restoring force model). The choice of equation parameters and their identification are discussedaccording to the building code, and it is proved that the model agrees with the test resultswell.
2007, 37(9): 77-79,88.
doi: 10.13204/j.gyjz200709017
Abstract:
Triaxial shear tests are done before and after vibratory load actings, and the testing samples are the red clay inXiamen. The effects of vibratory loading on sample' s cohesive force, internal friction angle, shear strength equation and theability to resist side distortion etc are studied by analyzing test data. After vibratory load actings, the cohesive strength indexand internal friction angle of the sample are decreased by 51. 72% and 50% respectively;and the shear strength curveshifts down obviously under same testing conditions.The results show that vibratory load acting is disadvantage tostabilization and bearing capacity of red clay.The research conclusions have theoretic and practical significance for us toprevent geotechnical engineering disasters and geologic disasters
Triaxial shear tests are done before and after vibratory load actings, and the testing samples are the red clay inXiamen. The effects of vibratory loading on sample' s cohesive force, internal friction angle, shear strength equation and theability to resist side distortion etc are studied by analyzing test data. After vibratory load actings, the cohesive strength indexand internal friction angle of the sample are decreased by 51. 72% and 50% respectively;and the shear strength curveshifts down obviously under same testing conditions.The results show that vibratory load acting is disadvantage tostabilization and bearing capacity of red clay.The research conclusions have theoretic and practical significance for us toprevent geotechnical engineering disasters and geologic disasters
2007, 37(9): 80-83.
doi: 10.13204/j.gyjz200709018
Abstract:
Two -dimensional finite element analysis of strip surface foundations resting on undrained two -layered subsoilunder the effect of combined vertical(V)and moment(M)loading has been applied to investigate the ultimate bearingcapacity and failure mechanism of the subsoil. In this analysis, the material response of the soil is represented with elasticperfectly plastic constitutive law yielding according to Mohr -Coulomb failure criterion. The surface foundation is assumed tohave no uplift capacity, and the footing may detach from subsoil under a V -M load combination, which is significantlydifferent from the fully attached footing. The ultimate bearing capacity of the foundation on layered subsoil is presented interms of the failure envelope in vertical and moment loading space. The effects of the thickness of upper soil, the width offooting and the shear strength of soilson the shape of the failure envelope are examined in details. It is found that the shapeof failure envelope ismainly depended onthe thickness of upper soil and the undrained shear strength ratio of two layers, andthe failure mechanism has two forms according to the combination of V -M loads.
Two -dimensional finite element analysis of strip surface foundations resting on undrained two -layered subsoilunder the effect of combined vertical(V)and moment(M)loading has been applied to investigate the ultimate bearingcapacity and failure mechanism of the subsoil. In this analysis, the material response of the soil is represented with elasticperfectly plastic constitutive law yielding according to Mohr -Coulomb failure criterion. The surface foundation is assumed tohave no uplift capacity, and the footing may detach from subsoil under a V -M load combination, which is significantlydifferent from the fully attached footing. The ultimate bearing capacity of the foundation on layered subsoil is presented interms of the failure envelope in vertical and moment loading space. The effects of the thickness of upper soil, the width offooting and the shear strength of soilson the shape of the failure envelope are examined in details. It is found that the shapeof failure envelope ismainly depended onthe thickness of upper soil and the undrained shear strength ratio of two layers, andthe failure mechanism has two forms according to the combination of V -M loads.
2007, 37(9): 84-88.
doi: 10.13204/j.gyjz200709019
Abstract:
In present computational model of the ant-i slide pile, the anchoring segment is assumed as elastic foundationbeam, and the quantitative of the landslide thrust can be calculated. So, these two computational conditions aredeterministic. But the distributions of landslide thrust on ant-i slide pile are approximately determined to be in shapes oftriangle, rectangle, or echelon, solely based on rock characters of the gliding mass. In this article, a new method isproposed to improve the calculation of distributionforms according to stability of the gliding mass sliding through the specifiedshear opening. It is assumed that the potential slide surface is composedof a part of the original slide surface and a circularsurface through the specified shear opening. If this safety factor of the specified shear opening is less than the design one,then the landslide thrust of the corresponding slide surface is calculated. The shear openings are specified at the pile fromtop to bottom by a certain interval. By this method, the landslide thrust at many points of the pile can be calculated. Theincrement of landslide thrust of the section between two adjacent shear openings can be obtainedby comparing the landslidethrust of adjacent shear openings. So, the distribution forms of landslide thrust of the pile from top to bottom can bedetermined. As far as the sliding mass forward the pile, it can supply resistance force only when its safety factor is biggerthan the design one, and its distribution law can be calculated by the same method as that of the landslide thrust. Based onall the calculation, a deterministic computational model of the ant-i slide pile can be established.
In present computational model of the ant-i slide pile, the anchoring segment is assumed as elastic foundationbeam, and the quantitative of the landslide thrust can be calculated. So, these two computational conditions aredeterministic. But the distributions of landslide thrust on ant-i slide pile are approximately determined to be in shapes oftriangle, rectangle, or echelon, solely based on rock characters of the gliding mass. In this article, a new method isproposed to improve the calculation of distributionforms according to stability of the gliding mass sliding through the specifiedshear opening. It is assumed that the potential slide surface is composedof a part of the original slide surface and a circularsurface through the specified shear opening. If this safety factor of the specified shear opening is less than the design one,then the landslide thrust of the corresponding slide surface is calculated. The shear openings are specified at the pile fromtop to bottom by a certain interval. By this method, the landslide thrust at many points of the pile can be calculated. Theincrement of landslide thrust of the section between two adjacent shear openings can be obtainedby comparing the landslidethrust of adjacent shear openings. So, the distribution forms of landslide thrust of the pile from top to bottom can bedetermined. As far as the sliding mass forward the pile, it can supply resistance force only when its safety factor is biggerthan the design one, and its distribution law can be calculated by the same method as that of the landslide thrust. Based onall the calculation, a deterministic computational model of the ant-i slide pile can be established.
2007, 37(9): 89-92,29.
doi: 10.13204/j.gyjz200709020
Abstract:
By doing the comparative tests, it is evident that the method of getting the core test samples will have someeffects on the result of RCM -test for determining chloride ion diffusivity in concrete, on the basis of which the cause ofeffects is analyzed and the suitable methods of getting the RCM -test samples are also proposed.
By doing the comparative tests, it is evident that the method of getting the core test samples will have someeffects on the result of RCM -test for determining chloride ion diffusivity in concrete, on the basis of which the cause ofeffects is analyzed and the suitable methods of getting the RCM -test samples are also proposed.
2007, 37(9): 93-96.
doi: 10.13204/j.gyjz200709021
Abstract:
It is studied that the properties of high -performance grouting admixture and grouting material prepared withgrouting admixture. The tests show that the grouting material prepared with cement(P-O 52-5R or P?O 42-5R), riversand, crushed stone and grouting admixture gives good technical properties, convenient construction and low cost. Withadding grouting admixture, grouting material can be preparedto meet the requirements of different projects, andthis groutingadmixture has been applied extensively in projects.
It is studied that the properties of high -performance grouting admixture and grouting material prepared withgrouting admixture. The tests show that the grouting material prepared with cement(P-O 52-5R or P?O 42-5R), riversand, crushed stone and grouting admixture gives good technical properties, convenient construction and low cost. Withadding grouting admixture, grouting material can be preparedto meet the requirements of different projects, andthis groutingadmixture has been applied extensively in projects.
2007, 37(9): 97-100,112.
doi: 10.13204/j.gyjz200709022
Abstract:
As a new style material in concrete field, crumb rubber concrete is providedwith perfect ability of holding backcrack, better resistance to shock load and better energy dissipation, and is very suitable for new pavement material. Theprimary study on bending strength of crumb rubber concrete is done. The main factors of affecting bending strength of crumbrubber concrete are analyzed by the study on bending strength of crumb rubber concrete with more crumb rubber (max to150kg /m 3 ), and empirical formula is created, also, the rationality of the formula is validated. It is discussed and analyzedthatthe correlation between bending strength and compressive strength of crumb rubber concrete, and the correspondingempirical formula is also created.
As a new style material in concrete field, crumb rubber concrete is providedwith perfect ability of holding backcrack, better resistance to shock load and better energy dissipation, and is very suitable for new pavement material. Theprimary study on bending strength of crumb rubber concrete is done. The main factors of affecting bending strength of crumbrubber concrete are analyzed by the study on bending strength of crumb rubber concrete with more crumb rubber (max to150kg /m 3 ), and empirical formula is created, also, the rationality of the formula is validated. It is discussed and analyzedthatthe correlation between bending strength and compressive strength of crumb rubber concrete, and the correspondingempirical formula is also created.
2007, 37(9): 101-103.
doi: 10.13204/j.gyjz200709023
Abstract:
The corroded steel bars, which are taken from the beams destroyed by the fatigue loads, are tested in the statictensile experiment. Then the obtained correlative mechanics parameters are analyzed to attain the relationship of thecorrosion ratio, the lifespan and the nominal yield strength of the corroded steel bars. The steel bars static mechanicalproperty transforms with the variation of fatigue stress amplitude and the corrosion ratio of bars.
The corroded steel bars, which are taken from the beams destroyed by the fatigue loads, are tested in the statictensile experiment. Then the obtained correlative mechanics parameters are analyzed to attain the relationship of thecorrosion ratio, the lifespan and the nominal yield strength of the corroded steel bars. The steel bars static mechanicalproperty transforms with the variation of fatigue stress amplitude and the corrosion ratio of bars.
2007, 37(9): 104-108.
doi: 10.13204/j.gyjz200709024
Abstract:
Based on the references available, the state -o-f the -art of wood members strengthened with FRP is summarized.FRP strips, sheets and bars are used to strengthenwood beams for improving their bending capacity and shear capacity, tostrengthen wood columns for increasing their compression capacity, and to improve their creep and ductility performance.And the key points needing further researches on wood structures strengthened with FRP are proposed.
Based on the references available, the state -o-f the -art of wood members strengthened with FRP is summarized.FRP strips, sheets and bars are used to strengthenwood beams for improving their bending capacity and shear capacity, tostrengthen wood columns for increasing their compression capacity, and to improve their creep and ductility performance.And the key points needing further researches on wood structures strengthened with FRP are proposed.
2007, 37(9): 109-112.
doi: 10.13204/j.gyjz200709025
Abstract:
The adhesive bonding technique has been widely used in construction as an alternative of conventional jointtechniques. Spew fillet and tapered plate are suggested to reduce the stress concentration in the adhesive layer of retrofittedbeams. Finite element (FE)analysis was employed to determine the effects of the spew fillet and the taper on interfacialadhesive stresses. The cases, including squaredend, outside taper, inside taper and withfillet, have been considered. Theresults of the FE analysis show that the adhesive stresses in the upper and the lower interfaces are different due to thesingularity at the adhesive corner. Both tapers and spew fillet can reduce the adhesive stresses. The spew fillet is better thantapers in reducing the normal stress, but the inside taper is more effective in reducing the shear stress than the fillet. Theresults also show that the results largely agree with the findings on lapjoints, but the effect of spew filletsisfar less thanthatfor lap joints.
The adhesive bonding technique has been widely used in construction as an alternative of conventional jointtechniques. Spew fillet and tapered plate are suggested to reduce the stress concentration in the adhesive layer of retrofittedbeams. Finite element (FE)analysis was employed to determine the effects of the spew fillet and the taper on interfacialadhesive stresses. The cases, including squaredend, outside taper, inside taper and withfillet, have been considered. Theresults of the FE analysis show that the adhesive stresses in the upper and the lower interfaces are different due to thesingularity at the adhesive corner. Both tapers and spew fillet can reduce the adhesive stresses. The spew fillet is better thantapers in reducing the normal stress, but the inside taper is more effective in reducing the shear stress than the fillet. Theresults also show that the results largely agree with the findings on lapjoints, but the effect of spew filletsisfar less thanthatfor lap joints.
2007, 37(9): 113-114,118.
doi: 10.13204/j.gyjz200709026
Abstract:
To quarantee the seismic behavior of adding frame steel structure and the integrity between adding structure andoriginal structure, the steel base joint is the key to the project of adding story. It is analysed the configurationof column basejoint of steel frame structure adding story when the original structure is a concrete frame structure, and it is pointed out theseismic inadequacy of the base joint used at present, and a new seismic constructional disposal of the joint of steel frameadding story on the top of a tall building is suggested.
To quarantee the seismic behavior of adding frame steel structure and the integrity between adding structure andoriginal structure, the steel base joint is the key to the project of adding story. It is analysed the configurationof column basejoint of steel frame structure adding story when the original structure is a concrete frame structure, and it is pointed out theseismic inadequacy of the base joint used at present, and a new seismic constructional disposal of the joint of steel frameadding story on the top of a tall building is suggested.
2007, 37(9): 115-118.
doi: 10.13204/j.gyjz200709027
Abstract:
Masonry pagodas are outstanding examples of ancient high -rise buildings. Built long ago, many pagodas aresuffered from earthquakes. To prevent them from destruction by earthquakes, it is necessary to research on seismicreinforcement methods for them with mechanism of seismic disaster. Applying time history analysis method, the XingjiaoTemple? s Pagoda in Xi-an, Shaanxi Province which is a key national relic, the seismic analysis has been done for it underhorizontal and vertical affects by earthquake. In light of calculation results, the forming mechanism of masonry pagodas isdiscussed and some seismic reinforcement measures are put forward.
Masonry pagodas are outstanding examples of ancient high -rise buildings. Built long ago, many pagodas aresuffered from earthquakes. To prevent them from destruction by earthquakes, it is necessary to research on seismicreinforcement methods for them with mechanism of seismic disaster. Applying time history analysis method, the XingjiaoTemple? s Pagoda in Xi-an, Shaanxi Province which is a key national relic, the seismic analysis has been done for it underhorizontal and vertical affects by earthquake. In light of calculation results, the forming mechanism of masonry pagodas isdiscussed and some seismic reinforcement measures are put forward.
2007, 37(9): 119-123.
doi: 10.13204/j.gyjz200709028
Abstract:
It is presented a 24m depth excavation supporting that is very near to the surrounding basement. Through thesuccessful using again of the adjacent excavation pile -anchor supporting for new excavation. s pile supporting structure, itwas solved the difficult problem of excavation supporting and saved much engineering expenses. It was monitoreddisplacement of the top of pile and stress of pile reinforcing bar and anchor dragging force, an effective forecasting system ofexcavation displacement was made and measures were also taken to ensure the excavation. s safety after unexpected waterleaking out of fire water pipe and typhoon rainstorm.
It is presented a 24m depth excavation supporting that is very near to the surrounding basement. Through thesuccessful using again of the adjacent excavation pile -anchor supporting for new excavation. s pile supporting structure, itwas solved the difficult problem of excavation supporting and saved much engineering expenses. It was monitoreddisplacement of the top of pile and stress of pile reinforcing bar and anchor dragging force, an effective forecasting system ofexcavation displacement was made and measures were also taken to ensure the excavation. s safety after unexpected waterleaking out of fire water pipe and typhoon rainstorm.
