Applied Mechanics and Materials Vol. 777

Abstract: Shield tunneling have varying degrees of impact on the surrounding buildings and the surrounding environment. Based on the shield tunneling of Hefei Subway Line 1 Ma'anshan viaduct, a 3D Fast Lagrangian Analysis of Continua is be used to simulate the shield tunnel construction and analyze the ground settlement and bridge pile deformation caused by tunnel construction. The numerical modeling results by analyzing the displacement variation and soil affected area at different distances show that when the shield tunnel excavation, the ground settlement becomes smaller with increasing distance from the shield center line of the pile and the maximum ground settlement is 10.778mm. The main deformation of bridge pile is in horizontal direction with a maximum horizontal direction of 2.0758mm. Horizontal displacement changes lager at the top of the pile, along with changes in the horizontal displacement of the pile depth becomes smaller, 15m is a turning point.

Abstract: HuJiaDi tunnel construction of Dai Gong highway is troublesome, the surrounding-rock mass give priority to full to strong weathering basalt, surrounding rock integrity is poor, weak self-stability of surrounding rock, and tunnel is prone to collapse. In order to reduce disturbance, taking advantage of the ability of rock mass, excavation adopt the method of "more steps, short footage and strong support". The excavation method using three steps excavation, The excavation footage is about 1.2 ~ 1.5 m; The surrounding rock bolting system still produce a large deformation after completion of the first support construction, it shows that the adopted support intensity cannot guarantee the stability of the tunnel engineering. Using ABAQUS to simulate tunnel excavation support, optimizing the support parameters of the tunnel, conducting comparative analysis with Monitoring and Measuring and numerical simulation results, it shows that the displacement - time curves have a certain consistency in numerical simulation of ABAQUS and Monitoring and Measuring.

Abstract: By the analysis of reinforced concrete slab, combined with experiment tests the feasibility of damaged plasticity model for concrete. Using parametric analyses, further the plastic damage model of related parameters set methods were discussed, concrete dilatation Angle, viscous coefficient, tensile stiffness, tensile damage on the results, in order to the design of slab-column connections engineering personnel to provide the reference.

Abstract: Dynamic characteristics calculation analysis on a super high-rise office building structure under seismic effect has been done by using currently popular software called PKPM in civil engineering. It turns out that the result calculated with PKPM software has great reference value for the seismic analysis of high-rise building structure. Analysis method tailored for dynamic characteristics of earthquakes in this paper can be used as reference for similar seismic analysis and design of super high-rise buildings.

Abstract: This study presents finite element analyses for a special steel bridge under the action an actual seismic wave. The maximum stress and the maximum deflection of the bridge are calculated based on the dynamic analyses. It is found that the bracing system and the beams between the two columns at the end of the bracing system are the critical members in the steel bridge under seismic action. The maximum displacement of the steel bridge is located at the overhang beams at the bridge end. However, the dynamic response is different when the seismic wave is input in different directions. Based on the numerical results, it is found that the special steel bridge is safe under the seismic action.

Abstract: The force performance of semi-rigid nodes connection between rigid connection and hinged connection ,which has very high strength and rigidity, good ductility and energy dissipation capacity. At present, it is one of the hot topics in the study of steel structure. This article will study about type T and cross-shaped frame plane frame node characteristics by some experiments. And we will observe the deflection of the two kinds of nodes, the force transmission mechanism and the failure pattern under low reversed cyclic loading test.And then compare the failure mechanism of failure mode and ultimate deformation state and hysteretic performance of the two kinds of nodes, The test results show that the yield load and the yield displacement and energy dissipation coefficient and the equivalent viscous damping ratio of Cross nodes are all greater than type T nodes’. So in the design of steel structure, increasing the component’s constraint can help to improve the seismic performance and stability of the whole structure.

Abstract: For a long-span prestressed concrete box-girder bridge erected by the double-cantilever segmental method, concrete of segmental joints and concrete in their nearby area may be different from integrally-cast concrete in structural performances. For example, the stiffness of segmental joints could be weakened significantly. To reveal influences of weakening in the stiffness of segmental joints on the deflection at mid-span of box girder, a typical continuous rigid frame bridge in China was taken as the analysis example, and its finite element models were established. In these models, weakening joints were simulated. After the validity of finite element models were warranted, the deflection in the completed construction stage and the long-term deflection in the running period of box girder were calculated, and then the variation of these deflections with the stiffness reduction in all segmental joints was described. Results showed that, compared with the shearing stiffness reduction in segmental joints, the bending stiffness reduction played more significant role in affecting the deflection of box girder. When the weakening times of joint stiffness arrived at 100, deflection values of the box girder increased significantly. However, in the practical engineering, the determination of stiffness reduction in segmental joints according by their damages, and the incorporation of weakening segmental joints into the bearing capacity assessment for existing box girders were all worth further study.

Abstract: Part of the bottom column in the frame structure is buried in the soil,sometimes it should be considered the affects from the body of the soil when calculating the ground floor of the frame structure. The Winkler assumes is quoted in this article, as considering the coefficient of the Soil-column interaction, the equivalent height calculating formula of the column restrained by the earth is deduced , this can change the frame structure that restrained by the earth into the commonly structure to calculate. It illustrates that the restrained load by the earth in the bottom of the structure has the big affects on the internal force and lateral. It provides a simple calculating method for such structure.

Abstract: Following with the development of construction industry, small diameter anti-sliding pile has been widely implemented in slope stabilization and deep foundation support. Much attention has been paid on researching lateral resistance of pile body. By orthogonally testing factors of small diameter anti-slide reinforcement pile models including concrete strength, sectional dimension and reinforcement bar gauge, The article analyzed sensitive influence to lateral resistance of pile body. The results indicate that concrete strength appears the most sensitive factor, next sectional dimension, and then reinforcement bar gauge. By comparing with shearing test of small diameter anti-slide reinforcement pile models, the conclusion follows that reinforcement of pile body does not fully unleash its shear resistance characteristic. Thus conclusion provides reference for implementation and designing of small diameter anti-slide pile.