In order to analyze the characteristics of pile-soil stress ratio of the composite foundation of cement-soil mixing pile under flexible foundation, this paper points out the displacement mode of friction pile; According to the deformation characteristic of friction pile, ascertain the neutral point of composite foundation. And this paper also derives the exact formula about length-stress ratio which addresses the problem of soft soil foundation according to the deformation co-ordination conditions of the pile composite foundation. The calculation of actual example proves that the formula about pile-soil stress ratio is in accordance with actual measurement number. The pile-soil stress ratio which addresses the problem of soft soil foundation is generally between 2~4. If other conditions keep invariable, pile-soil stress ratio become big when cushion modulus become big. Cushion modulus effect the length-stress ratio greatly.

Retinal vascular bypass surgery (RVBS) is a kind of complicated operation, with high precision and dexterous manipulation limited to small workspace. It is necessary to design a robot-assisted manipulator for performing such a task. The process of RVBS is described according to clinic operation at first. The motion of surgeon and workspace of surgical instruments are analyzed; correspondingly, motions of robot-assisted manipulator are obtained. Then, mechanism of manipulator including remote center of motion (RCM) is proposed through considering constraints induced by pierce points of sclera. Finally, inverse kinematics of the proposed robot-assisted manipulator is done to realize retinal surface motion. The analysis results show the end-effectors of robot-assisted manipulator can reach arbitrary position on the retinal surface.

The unification differential equation of buckling and motion of viscoelastic beam subjected to the uniformly distributed follower forces in time domain was established by differential operators including extension viscosity, shearing viscosity and moment of inertia. According to the unification differential equation, dynamic stability of three-parameter model of viscoelastic beams subjected to follower forces with clamped-free supported boundary condition was firstly analyzed by power series. The relations of the follower force versus vibration frequency and decay coefficient were obtained, so was the effect of viscous coefficient on the critical load of beams.

The field socket gas pipeline is taken to make the loading experiment in order to study the deformation and force state of the pipelines and the limit value of the deformation curvature of the pipeline．The monitoring data from the shield tunnel construction are analyzed, the effect of shield tunneling on the deformation of ground surface and buried pipelines is studied, and the rationality of the deformation monitoring value of gas pipelines in the Shenyang area is discussed．

Time domain analysis on earthquake response of soil-asymmetric structure interaction system was carried out in this paper in order to study the feasibility of the forced decoupling method. Acoording to lateral-torsional coupling vibration equations of soil-asymmetric structure system, the direct integral MATLAB program in time domain were made used method. Feasibility of forced decoupling method was carried out by comparing the result in time domain with the result in frequency domain. Finally, it is derived that the results are very close to each other, which verify the feasibility of forced decoupling method. This conclusion can supply references to engineering calculation and design of structure.