Experimental Study And Numerical Analysis Of Mechanical Behavior Of Pile Foundation-Trimmer Beam-Retaining Wall Structure

Retaining wall is widely used in the construction of civil, hydraulic & electrical and traffic engineering. Among various kinds of forms, shelf-retaining wall is the most popular because of its multiplex advantages, such as simple structure, ease of constructability, and convenient procurement of local resources, etc. However, shelf-retaining wall holds rigid requirement upon the properties of foundation. In situation where the bearing capacity of the foundation can't meet the requirement of designing, the trimmer beam and pile foundation are usually designed under the retaining wall to transfer force from the retaining wall to the pile foundation through the trimmer beam to satisfy the requirements of the foundation. Hence the pile foundation, trimmer beam and retaining wall often appear as a braced retaining frame in engineering applications. Since the soil-structure interaction relates to many factors, and hyperstatic elements exist in the interaction between structures, up to now people can't thoroughly address the mechanism between the P-T-R structure and the soil mass. Further research is expected on the stressing characteristics and interaction of the pile foundation, trimmer beam and retaining wall. The study mainly consists of two parts: model experiment and finite element analysis. The goal is to study the forms of action and law of distribution of earth pressure of the backsoil, the transformation of pile foundation and the form of stressing of the trimmer beam, analyze the trend of settlement and transformation of the system, stress distribution of each structure of the system, and the value and distribution of the earth pressure of the backsoil, and reveal the main factors affecting the earth pressure of the backsoil and bearing capacity of pile foundation according to different foundations by means of model experiment and numerical analysis. Through the study and analysis the current calculation & analysis model of P-T-R structure is tested to verify the adequacy of the traditional designing method, enhance the rationalization of designing of P-T-R structure and accelerate the rapid development of the braced retaining structure in engineering applications. Both the earth foundation and batholith experiment schemes are adopted according to different conditions of foundation. The finite element analysis goes for comparison with the results of experiments and further analysis and calculation of the parts which can't be involved in experiments. The following results are obtained from the model experiment and finite element analog computation: 1.the trend of settlement and transformation of P-T-R structure ,stress distribution of the system, the value and distribution of the earth pressure of the backsoil; 2.the force of friction between earth pressure of the backsoil, the pile foundation and the soil mass and the variation of the pressure ; 3.the main factors affecting the action of the soil mass and the structure ,the stressing characteristic of the structure and the transferring mechanism between them.