Applied Mechanics and Materials Vols. 204-208

Abstract: After the Wenchuan earthquake, a large number of infilled frame structure of underlying weak layer (the bottom of non-filled walls, the upper wall of clouds filling) of the housing system did not appear "weak beam strong column" of the failure mode. Established pure frame structure of finite element model which considered the quality of in filled wall without taking into account of its stiffness and strength and the frame of finite element model which contains filler wall, and carried out elastic-plastic time-history analysis with established finite element model of two under earthquake, through analysis and comparison understand reasons which infilled frame structure of underlying weak layer did not achieve the "weak beam strong column" ductile failure mechanism, and further explored how to achieve "weak beam strong column" failure mechanism for infilled frame structure of underlying weak layer, raised a number of assurance measures.

Abstract: The railway canopy and mechanical canopy in the granary are large span special structure industrial architecture, has the design standard uncertainty, influence factor multiplicity, construction craft complexity questions and so on in the design and the construction. On the basis of obtaining the characteristics of granary railroad canopy, the design methods of roof, column and foundation for granary railway canopy are described, the defects of stability theory are analyzed, and the reasons of instability is summarized in this paper. The results will has good reference to similar projects in the future.

Abstract: Considering the structure type and load feature of vertical lifting tridimensional parking structures are similar to those of bamboo, a new structure arrangement style of tridimensional parking structure is presented, that is to set hoop-layers like bamboo knots at its proper height, according to the imitating bamboo principle that any two adjacent hoop-layers have equal stability and lateral displacement. The static and stability property of imitating bamboo structure and non-imitating bamboo structures is studied. It is shown that the lateral displacement of imitating bamboo structure is constrained effectively and the storey relative lateral displacement becomes smaller and more uniformly distributed; additionally, the internal force mutation of columns is relatively moderate and resisting overturning ability of structures is enhanced; moreover, the overall stability of structures controlled by equivalent short columns results in the great improvement of stability bearing capacity. All above verifies the rationality of the imitating bamboo principle.

Abstract: Many thin cylindrical shells are used in structural applications in which the dominant loading condition is global bending. Key examples include chimneys, tubular piles, wind generation towers and tall silos. Their thickness lies in a tricky range which is extremely thin for the structural tube community and very thick for the shell buckling community. The buckling strength of these structures is dominated by extensive plasticity, but the fully plastic state is usually far from being attained. This paper explores the buckling strength of imperfect thin cylindrical shells under global bending in the elastic-plastic range. The capacity curves of the new Eurocode EN 1993-1-6 (2007) are used to match the final results. The results show that the capacity curves can capture this buckling behavior accurately and safely for different types of material models. It is assumed that the shell is held circular by rings or boundaries at reasonable intervals, effectively restraining ovalisation. It is hoped that these results will make a useful contribution towards resolving the misunderstandings and controversy that has been evident in this field in recent years.

Abstract: How to determine cable’s pretension is one of key problems in pre-stressed mega brace and steel frame structure. According to superposition principle of structural deformation, the inner force increment of pre-stressed cable under vertical and horizontal loads was approached separately by analyzing the structural deformation and inner force increment. Based on the rule that the required pre-tension force of cable equals to the sum of inner force increment of compressed cable under vertical and horizontal load, the qualitative estimation theory on cable’s initial pre-tension considering construction influence is ultimately established.

Abstract: The welding quality of the steel structure is one of the most important segments in the whole construction project, especially in the condition of special geographical environment and wicked climate. In this article, by means of the mechanical test and finite element simulation analysis, a welding treating technology has been summarized in the subzero surrounding, which is based on the fundamental of component size selecting, preheat, heat preservation, and change of the ambient temperature including the rising material temperature before welding. Therefore the thermal crack and cold crack can been effectively eliminated. Rigorous controlling the temperature of the welding procedure and scientific construction play an important role to ensure the welding quality of the big span truss beam and column.

Abstract: This paper takes the under-frame of 300t storage silo produced by a certain company as the main research subject, modal analysis on the under-frame is made by three-dimension finite element method to obtain the basic natural vibration period,modal parameters and the distribution characteristics of the overall stiffness.The best optimal design can be got through the optimization design of the under-frame.All of the above provide a reliable reference for the design of storage silo.

Abstract: Four specially shaped columns with HRB500 reinforcement were tested under low cyclic loading. The hysteretic curve, yield load, ultimate load, displacement ductility and rigidity degradation were compared in order to research the effect of axial compression ratio on ductility and bearing capacity of specially shaped column with HRB500 reinforcement. It is shown that the axial compression ratio has greater influence on ductility and bearing capacity. With the increase of axial compression ratio, the bearing capacity of HRB500 reinforcement concrete specially shaped column can be enhanced while the deformation capacity becomes worse. The hysteretic characteristic of specially shaped columns with HRB500 reinforcement is improved and the stiffness degeneration becomes slow with the decrease of axial compression ratio.

Abstract: Sheli Tower in Jing chuan county is a steel frame system, whose connected construction between steel components and antiqued components is very complex. Considering the construction difficulties of Sheli Tower,this paper introduces how to fix the wooden brackets by using welding screw and steel sheet that connected with the columns and the method of packaging the steel eaves purlins into cornice with wooden antiqued components.These solutions ensure the union of force and architectural form, accurately comply with the architecture of Tang style.

Abstract: It introduces the current research status about prestressed concrete cable-beam structure system at home and abroad, and anylyzes the phase of elasticity-plasticity by the FEM software.In this paper ,it builds the geometric models of slabs in different thickness and gets all kinds of results.It compares the results of different slabs and gets the conclusion that the working mechanism of beam changes with the quantity adding of cable.