Applied Mechanics and Materials Vols. 351-352

Abstract: To ensure the safe use of double column tri-axis deflection machine for processing and manufacturing railway vehicles. This paper analyzes the use conditions of double column tri-axis deflection machine, and makes a contact nonlinear finite element analysis on various typical use conditions. The positions of parts subject to danger can be found out through the results of static strength analysis, which finds out the weaknesses and prejudges the failure trend of parts, and which provides guidance for prejudging the faults in actual production and can prevent occurrence of accidents.

Abstract: Now concrete beams reinforced with near surface mounted FRP bars has been researched at home and abroad. This article research the Bearing capacity of concrete beams reinforced with near surface mounted FRP bars by test, and also, Immunobead binding test, infer the calculation formula of ultimate bearing capacity with near surface mounted some bars base on the the single bar.

Abstract: The current research work lacks systematizations on ductility features in failure process for cable-strut arch structures. To improve this disadvantage, an intensive study is performed with the strategies of experimental verification and finite element analysis. Firstly, considering the mechanical characteristics of cable-strut arch structures, a calculation method of displacement ductility are proposed to analyze its features in failure process. On this basis, the law of ductility features on bearing failure for cable-strut arch structures, is studied through the analysis of the results of experimental verification and finite element analysis. It indicates that their failures are brittle. It provides some references for the reasonable design of these structures.

Abstract: Put forward binding bars prestressed concrete filled steel box girder and analyses it’s advantage, Study on the bending moment by the fiber model method to analyze the beam-Curvature and load-Relation curves of deflection theory.Through the finite element software analysis of prestressed concrete steel box beam prestressed concrete filled steel tubes and four ways to set binding bars the ultimate bearing capacity of the beam,Analysis of the influence of the thickness of the steel plate and rod diameter, constraint, constraint rod axial spacing on various beam flexural capacity.The results show that,Binding bar has more advantages for prestressed concrete steel box using a thin plate bending ability improvement,Diameter, spacing of the binding bars binding bars as long as not bending capacity of prestressed concrete with binding bars of steel box beam structure under the condition of impact.

Abstract: To reveal the harm of member initial stress on space frame structure, several models which are different in initial imperfection methods, material computational models and upper optimized stress ratios are employed to do nonlinear finited element analysis. It finds that the initial stress method and Marshall model are more accurate to simulate. When design the space frame structure, it must be avoided to optimize the cross section excessively in pursuit of economic factors.

Abstract: Prestressed tendon constraint partial compression concrete is a new approach to solve the phenomenon of insufficient bearing capacity in partial compression concrete members .The keystone of Strut-and-tie theory is presented.The development of strut-and-tie model is in-depth analyzed based on the description of the stress distribution in the members , the author considers that this theory can yet be regard as an ideal calculation method in partial compression members which is constrained by prestressed tendon or steel mesh.

Abstract: A full rang of external prestressing CFRP concrete box girder flexural performance have been tested. Crack distribution, deflection,strain distribution, stress increment of external CFRP have been measured. The results demonstrate that that as the load increase, the shear lag phenomenon on the upper and bottom plate of the box girder is more significantly; There is a certain friction Loss on the interface between CFRP and two steering block which arrange in the mid-span. If suitable element models and material constitutive laws are chose, the ANSYS program may simulate the fully flexural experimental process of the box girder, the result is well agree with the experimental result.

Abstract: A practical connection method of wall-column subassembly in new precast reinforced concrete frame-shearwall structure was proposed in this paper. Based on the general finite element software ABAQUS, numerical simulations were carried out on the mechanical performance of the precast and cast-in-situ wall-column subassemblies by using concrete damaged plastic model and bilinear kinematic hardening model. Results showed that mechanical performance of the precast wall-column subassembly, such as carrying capacities, deformations and failure modes, were almost equal to the cast-in-situ wall-column subassembly. Feasibility of the connection method which this paper proposed is verified preliminarily. The research results can provide theoretical references for related experimental researches, engineering designs and constructions.

Abstract: This paper focuses on the numerical simulation of the flexural behavior of reinforced concrete beams under impact loading by the LS-DYNA finite element code. An enhanced version of the Concrete Damage Model Release 3 (K&C) was used for the concrete materials and a Plastic Kinematic Model was adopted for steel reinforcement, both material models used parameters to cope with the effects of strain rate. The simulation also took the bond between concrete and steel bar into consideration, and its behavior model was based on high strain rate experimental results. The simulation of the mid span drop tests, both with and without bond consideration, were compared to experimental results to investigate the influence of bond consideration and the reliability of the overall simulation model. Compared with experimental results, the calculated mid-span deflections with the bond model agreed much better than those without the bond model, and a simplified formulation was drawn from the trend on deformation depending on the impact velocity.

Abstract: The multi-tower large basement structure is some different with general super-long structure in crack control due to thermal stress. Characteristics of thermal stress in the multi-tower large basement structure were analyzed. The effective crack control measures aiming at multi-tower large basement structure are put forward. Low grade of concrete is preferred. The maximum concrete shrinkage should be limited in bid document. Double-layer two-way reinforcements in upper plate should be increased according to stress value to ensure crack width. Setting groove in exterior walls of the basement, spacing 30~50 meters, can effectively reduce thermal stress. Covering on upper plate should be overlaid timely as long as bearing capacity of the structure meets requirements.