Advanced Materials Research Vols. 163-167

Abstract: The differential equations about distortional buckling are established according to the distortional buckling mode of cold-formed thin-walled C steel on the lateral and vertical loads. The formula of critical moment is obtained according to the differential equations of bending. This formula can calculate the critical moment if the properties of the section of C steel are given.

Abstract: By terms of the numerical modeling of ABAQUS software, the analysis of the stress concentration factor (SCF) of tubular T-joints subjected to axial load is analyzed in this paper. The magnitude and the distribution of the SCF are also obtained. Through the finite element analysis of 816 models, the effect of geometrical parameters on the value and distribution of the SCF is investigated. Then based on these results, the parametric equations of the maximal SCF and SCF distribution for T-joints subjected to axial load are presented. Error analysis of these parametric equations is also carried out.

Abstract: By setting cables and struts in place in the single-layer cylindrical latticed shell, a new-style prestressed spatial steel structure--cable supported barrel vault structure is constructed, the static load test research on which is carried out for the first time in this paper. Based on the prototype building, a scale model with the scale of 1:15 is designed and manufactured for the test. The research results indicate, the static behavior of the prototype structure can be reflected approximately by this scale model. The static behavior of the single-layer cylindrical latticed shell is improved significantly by adding cables and struts, i.e., the cable supported barrel vault structure is a kind of highly efficient prestressed spatial steel structure. Compared with the case of full-span load, the half-span load makes the cable supported barrel vault structure unsafer.

Abstract: The wide range of grouting technology, theory and construction technology are relatively mature, but as a result of the promotion of its application is still uneven, and grouting construction works are hidden, so often cost more is spent in grouting reinforcement work, but the expected results of the problem is not yet achieved. In this paper, it is given a comprehensive summary of the effect of grouting and the application of inspection techniques. It is given analysis of the key issues of technology, and hopes to provide reference with the grouting reinforcement of engineering practice.

Abstract: The paper designs the models of double-tube BRBs with contact rings by applying the existing general materials and carries out an experimental research on static properties, exploring on its bearing performance under the condition of unidirectional loading and the relationship between the bearing performance and the stiffness of outer-tube, clearance and slenderness ratio of inner-tube, so as to provide references for the engineering application of double-tube BRBs with contact rings.

Abstract: A structure with “changeable boundaries”, changed from construction stage to service stage, is a new design idea used in long span spatial structures. The inner force distribution will be more reasonable and the structure self-weight will be lighter, if the idea is adopted. Adoption of the idea enables the inner force distribution of the structure changing from the construction stage to the service stage. Although the time of the inner force changing is much short, it has a significant influence on the loading behavior and the construction cost of the structure. As an example, a simple beam with different boundaries (unchangeable and changeable), under uniformly distributed lateral loads, is analyzed in this paper. Through static analysis, the loading behavior of the beam under three different boundaries, including simple support, fixed support and changeable boundary, is compared. The linear buckling behavior of the beam with changeable boundaries is also investigated. The critical equilibrium equation is derived subsequently for computing the critical stability load. A new computation method for the beam with changeable boundaries is proposed.

Abstract: Steel bridge towers have been widely applied in the countries like the United States and Japan for many years. However, in recent years, China has begun to use steel bridge towers in the bridge construction because of the national situation. In this paper, the development, application and related researches of steel bridge towers in China are presented. Two tests on the local buckling behaviors of steel bridge towers are introduced. Through the tests, the local buckling modes and mechanical characteristics of steel bridge towers are summarized and analyzed, and the mechanical behaviors between steel bridge towers with different cross sections are also demonstrated. The new achievements have been adopted by the new edition of China highway steel bridge design code. At last, the prospects of steel bridge towers are discussed.

Abstract: This paper investigates the flexural strength and ductility of hybrid high performance steel (HPS) I-beams. Three simple supported I-beams were tested to study the bending behavior of hybrid beams with Q&T HPS 485W in flanges and Q235 in webs. Experimentally verified nonlinear finite element modeling techniques were then employed in a parametric study including the influence of cross section compactness and material match in hybrid design on rotation capacity of beams. It is observed that the compactness of flange and web have a major influence on the rotation capacity of flexural beam. As a result, appropriate compactness criteria are suggested for use in the design of HPS 485W hybrid beams employing compact webs made from lower strength steels.

Abstract: The roof structures of Guangzhou South Railway Station are long-span spatial steel structures, The form and structure system are complicated. Prestress cable-arch structure, cable-shell structure and tri-directional truss-string spatial structure are applied. It recommend the construction and design process of roof structure, and also give an analysis of roof structure's working principle on prestress cable-arch structure , cable-shell structure, and the tri-directional truss-string structures. The results show that working stability of the roof structures is good.

Abstract: Use finite element analysis software ABAQUS to analyze the bearing capacity, strength and wave attenuation performance of very large ocean engineering floating structure based on spatial grid structure, and analyze selected ocean engineering floating structures with different geometrical dimensions. The ocean engineering floating grid structure attenuates wave effectively, whose bearing capacity and strength are high. In the static loads and wave forces analysis, with the dip angle α of belly poles increasing, the maximum stresses decrease, and the bearing capacity lowers; with the height h of the pyramid larger, the maximum stresses and the bearing capacity increase; with the od D of the poles and sphere joints subjoining, the maximum stresses change in concave shape in the whole, and the bearing capacity increases in turn; with the wall thickness t1 of the poles increasing, the maximum stresses under static loads become smaller, but under wave forces the maximum stresses change in concave shape, the bearing capacity declines. The bearing capacity, strength and wave attenuation performance of the structure are influenced by it’s geometrical dimension regularly, and so will affect the project implementation in a practical way.