Because of urbanization,land resources in China’s cities has become increasingly scarce.Therefore,modern buildings are becoming taller,making high-rise steel frame structures the new favorite of the construction indu...Because of urbanization,land resources in China’s cities has become increasingly scarce.Therefore,modern buildings are becoming taller,making high-rise steel frame structures the new favorite of the construction industry.However,the construction of high-rise steel frame structures requires advanced technology.If the construction technology is effectively implemented and the welding techniques of the construction personnel align with the requirements for high-rise steel frame structures,it can help mitigate deformations in the steel structure,thus preserving the overall construction quality of high-rise steel frame structures.To enhance the applicability of steel frame structures in high-rise buildings,this paper focuses on analyzing the optimization path for the construction process of high-rise steel frame structures.It introduces a tailored approach to control welding-induced deformations in steel frame structures,aiming to make a valuable contribution to the advancement of China’s construction industry.展开更多
The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA. The multi-material Eulerian and Lagrangian coupling algorithm was adopted. A flu-id-structure coupling finite ele...The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA. The multi-material Eulerian and Lagrangian coupling algorithm was adopted. A flu-id-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground, multiple ALE element for simulating air and TNT explosive material. Numerical simulations of the blast pressure wave propagation, struc-tural dynamic responses and deformation, and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed. The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure. The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation. The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic defor-mation subjected to intensive blast waves, and columns lost carrying capacity, subsequently lead-ing to the collapse of the whole structure. The approach coupling influence between struc-tural deformation and fluid load well simulated the progressive collapse process of structures, and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load.展开更多
Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle's frame. Results indicated that the maximum stress occurs on the front beam 's variable section area. Dynamic ...Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle's frame. Results indicated that the maximum stress occurs on the front beam 's variable section area. Dynamic sensitivity analysis elucidated the relationship between the maximum stress and the thickness of a particular beam,e. g.,top,middle,and bottom beam. Displacement was analyzed by the key part that influenced the maximum stress. Finally,the new plan using BS960 super-high-strength beam steel and the preferred beam thickness was compared with the original plan. New combinations of beam thickness were introduced on the basis of different purposes; the maximum responding light w eight ratio was 21%.展开更多
The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has ...The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has been rapidly developed and widely used in the field of the civil engineering because of its high building applicability,the fast construction speed,the low cost of the foundation and the good mechanical properties.Various kinds of the large-span,heavy-load and high-rise buildings emerge in endlessly,and the requirement for the structural performance is becoming higher and higher.The reinforced concrete column-steel beam composite frame structure is a high-performance structural system with the broad development prospects in China because of its good mechanical performance,durability,fire resistance and the building use space.展开更多
In order to find out the dynamic characteristics of a steel frame structure project in the 8 degree (0.3g) area, the artificial wave, Taft wave and El Centro wave were input by using the finite element analysis softwa...In order to find out the dynamic characteristics of a steel frame structure project in the 8 degree (0.3g) area, the artificial wave, Taft wave and El Centro wave were input by using the finite element analysis software ANSYS. The dynamic time-history analysis of the structure shows the dynamic performance of the structure under the frequent earthquakes and rare earthquakes.展开更多
Determining initial pretension values of pre-stressed cables is one of the key problems for a steel mega frame and pre-stressed composite bracing structure.Through the mechanical analysis of the composite bracing unde...Determining initial pretension values of pre-stressed cables is one of the key problems for a steel mega frame and pre-stressed composite bracing structure.Through the mechanical analysis of the composite bracing under vertical loading,the critical factors deciding the initial pretention value were found.According to these factors,a rule for the initial pretension value was put forward.The determination equations were acquired based on the principle of force equilibrium at nodes.The numerical results indicate that the internal force disequilibrium in composite bracings resulted from symmetrical load can be eliminated only in a symmetrical way,so that initial pretention values are decided only by vertical loads.The influencing coefficient leveling method,taking into account interactions between story and story,is accurate and feasible.展开更多
The study on the dynamic characteristics of light steel residential structural system has both theoretical and practical significance for the application and promotion of light steel residential structural system. In ...The study on the dynamic characteristics of light steel residential structural system has both theoretical and practical significance for the application and promotion of light steel residential structural system. In this paper, we analyze several common types of light steel residential structural system, describe the dynamic characteristics of the light steel residential structural system for an overview on the basis of former related studies, and then summarize the advantages of light steel residential structure system.展开更多
On the 2011 off the Pacific Coast of Tohoku Earthquake, gymnasium buildings exhibited the unexpected structural damages, which prevented a use as evacuation shelters in during- and post-disaster periods. The major fai...On the 2011 off the Pacific Coast of Tohoku Earthquake, gymnasium buildings exhibited the unexpected structural damages, which prevented a use as evacuation shelters in during- and post-disaster periods. The major failure occurr<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ing</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> on the connection between the RC column top and steel roof as well as the cracks in the RC column base w</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">as</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> observed during the emergent inspection. According to the earlier studies, it was implied that the presence of the slotted hole possibly deteriorates the seismic capacity;however, the length of slotted hole was fixed at a certain value. Facing this concern, this research attempts to clarify the influence of the slotted hole length through a comprehensive parametric study by pushover and seismic response analyses. In conclusion, it has been discovered that the slotted hole deteriorates the seismic capacity for the connection failure up to almost 50% of that without slotted hole. Moreover, the discrepancy of characteristics obtained by the static and dynamic analyses is originated by means of the presence of slotted hole. This slotted hole effect should be noted by structural engineers and researchers to provide the adequate seismic diagnosis and strengthening.</span></span></span>展开更多
In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, s...In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.展开更多
Input ground motions have significant impacts on the uncertainty of structural responses in time-history analysis.In this study,records were selected and scaled for the evaluation of mean structural responses accordin...Input ground motions have significant impacts on the uncertainty of structural responses in time-history analysis.In this study,records were selected and scaled for the evaluation of mean structural responses according to the target spectrum.The Newmark-Hall spectrum is closely related to seismic response of short,medium and long-period structures,so it was taken as the target spectrum here.The nonlinear time-history analyses of 9-story and 20-story steel moment-resisting frame structures were carried out as examples.They represent medium and long-period buildings,respectively.Three target spectra with risk of 50%,10%and 2%probabilities for exceedance in 50 years were calculated by the average Newmark-Hall spectrum method for three ground motion sets developed in the SAC Steel Project.The predicted structural mean responses of these Newmark-Hall spectra were compared with those calculated by the average spectral acceleration method for the same record set.It is found that both methods have similar accuracy for estimating the structural mean response.However,the method proposed herein is more effective in reducing the variability of the structural responses.Also,the proposed method is more advantageous for the time-history analysis of long-period structures or structures with more severe nonlinear responses under strong seismic excitations.展开更多
Taking the construction project of the National Cybersecurity Talents and Innovation Base as an example,this paper studies the construction technology of freeform surface spatial bending-torsion steel structure based ...Taking the construction project of the National Cybersecurity Talents and Innovation Base as an example,this paper studies the construction technology of freeform surface spatial bending-torsion steel structure based on structural design model transformation,including the parametric modeling of deepening design model,computer-aided bending and torsion frame production,flexible docking in the bending-torsion combination unit,and welding stress deformation,in hope to provide reference for similar projects in the future.展开更多
文摘Because of urbanization,land resources in China’s cities has become increasingly scarce.Therefore,modern buildings are becoming taller,making high-rise steel frame structures the new favorite of the construction industry.However,the construction of high-rise steel frame structures requires advanced technology.If the construction technology is effectively implemented and the welding techniques of the construction personnel align with the requirements for high-rise steel frame structures,it can help mitigate deformations in the steel structure,thus preserving the overall construction quality of high-rise steel frame structures.To enhance the applicability of steel frame structures in high-rise buildings,this paper focuses on analyzing the optimization path for the construction process of high-rise steel frame structures.It introduces a tailored approach to control welding-induced deformations in steel frame structures,aiming to make a valuable contribution to the advancement of China’s construction industry.
基金Supported by National Natural Science Foundation of China(No.50608026)
文摘The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA. The multi-material Eulerian and Lagrangian coupling algorithm was adopted. A flu-id-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground, multiple ALE element for simulating air and TNT explosive material. Numerical simulations of the blast pressure wave propagation, struc-tural dynamic responses and deformation, and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed. The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure. The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation. The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic defor-mation subjected to intensive blast waves, and columns lost carrying capacity, subsequently lead-ing to the collapse of the whole structure. The approach coupling influence between struc-tural deformation and fluid load well simulated the progressive collapse process of structures, and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load.
文摘Static strength finite element analysis was conducted to decrease the weight of a skeleton vehicle's frame. Results indicated that the maximum stress occurs on the front beam 's variable section area. Dynamic sensitivity analysis elucidated the relationship between the maximum stress and the thickness of a particular beam,e. g.,top,middle,and bottom beam. Displacement was analyzed by the key part that influenced the maximum stress. Finally,the new plan using BS960 super-high-strength beam steel and the preferred beam thickness was compared with the original plan. New combinations of beam thickness were introduced on the basis of different purposes; the maximum responding light w eight ratio was 21%.
文摘The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has been rapidly developed and widely used in the field of the civil engineering because of its high building applicability,the fast construction speed,the low cost of the foundation and the good mechanical properties.Various kinds of the large-span,heavy-load and high-rise buildings emerge in endlessly,and the requirement for the structural performance is becoming higher and higher.The reinforced concrete column-steel beam composite frame structure is a high-performance structural system with the broad development prospects in China because of its good mechanical performance,durability,fire resistance and the building use space.
文摘In order to find out the dynamic characteristics of a steel frame structure project in the 8 degree (0.3g) area, the artificial wave, Taft wave and El Centro wave were input by using the finite element analysis software ANSYS. The dynamic time-history analysis of the structure shows the dynamic performance of the structure under the frequent earthquakes and rare earthquakes.
基金Project of Ministry of Housing and Urban-Rural Development of China(No.2012-K2-28)
文摘Determining initial pretension values of pre-stressed cables is one of the key problems for a steel mega frame and pre-stressed composite bracing structure.Through the mechanical analysis of the composite bracing under vertical loading,the critical factors deciding the initial pretention value were found.According to these factors,a rule for the initial pretension value was put forward.The determination equations were acquired based on the principle of force equilibrium at nodes.The numerical results indicate that the internal force disequilibrium in composite bracings resulted from symmetrical load can be eliminated only in a symmetrical way,so that initial pretention values are decided only by vertical loads.The influencing coefficient leveling method,taking into account interactions between story and story,is accurate and feasible.
文摘The study on the dynamic characteristics of light steel residential structural system has both theoretical and practical significance for the application and promotion of light steel residential structural system. In this paper, we analyze several common types of light steel residential structural system, describe the dynamic characteristics of the light steel residential structural system for an overview on the basis of former related studies, and then summarize the advantages of light steel residential structure system.
文摘On the 2011 off the Pacific Coast of Tohoku Earthquake, gymnasium buildings exhibited the unexpected structural damages, which prevented a use as evacuation shelters in during- and post-disaster periods. The major failure occurr<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ing</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> on the connection between the RC column top and steel roof as well as the cracks in the RC column base w</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">as</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> observed during the emergent inspection. According to the earlier studies, it was implied that the presence of the slotted hole possibly deteriorates the seismic capacity;however, the length of slotted hole was fixed at a certain value. Facing this concern, this research attempts to clarify the influence of the slotted hole length through a comprehensive parametric study by pushover and seismic response analyses. In conclusion, it has been discovered that the slotted hole deteriorates the seismic capacity for the connection failure up to almost 50% of that without slotted hole. Moreover, the discrepancy of characteristics obtained by the static and dynamic analyses is originated by means of the presence of slotted hole. This slotted hole effect should be noted by structural engineers and researchers to provide the adequate seismic diagnosis and strengthening.</span></span></span>
文摘In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.
基金National Natural Science Foundation of Hebei Province under Grant No.E2020202038the National Natural Science Foundation of China under Grant No.51778206。
文摘Input ground motions have significant impacts on the uncertainty of structural responses in time-history analysis.In this study,records were selected and scaled for the evaluation of mean structural responses according to the target spectrum.The Newmark-Hall spectrum is closely related to seismic response of short,medium and long-period structures,so it was taken as the target spectrum here.The nonlinear time-history analyses of 9-story and 20-story steel moment-resisting frame structures were carried out as examples.They represent medium and long-period buildings,respectively.Three target spectra with risk of 50%,10%and 2%probabilities for exceedance in 50 years were calculated by the average Newmark-Hall spectrum method for three ground motion sets developed in the SAC Steel Project.The predicted structural mean responses of these Newmark-Hall spectra were compared with those calculated by the average spectral acceleration method for the same record set.It is found that both methods have similar accuracy for estimating the structural mean response.However,the method proposed herein is more effective in reducing the variability of the structural responses.Also,the proposed method is more advantageous for the time-history analysis of long-period structures or structures with more severe nonlinear responses under strong seismic excitations.
基金The Hubei Provincial Building Technology Project in 2021(No.43)。
文摘Taking the construction project of the National Cybersecurity Talents and Innovation Base as an example,this paper studies the construction technology of freeform surface spatial bending-torsion steel structure based on structural design model transformation,including the parametric modeling of deepening design model,computer-aided bending and torsion frame production,flexible docking in the bending-torsion combination unit,and welding stress deformation,in hope to provide reference for similar projects in the future.
