Research On Similarity Of Small Scale Reinforced Concrete Structural Model

Earthquake simulation test has developed for several decades since it is been used, meanwhile, model similitude theory has got a great development. However, prototype material hardly be used in small-scale RC structure model test, in addition, to research the seismic response of the model excited by vary level ground motions, step loading is usually be used; then following problems have to be analyzed:(1) The problem of similitude harmony between vary materials (reinforcement and concrete) should be considered in RC model design.(2) Step loading is usually be used in shaking table test, so accumulative damage existing in the model when it is excited by repeated ground motions, then, errors existing in experiment results.In this thesis,following research has been done according to the problems above:(1) This paper presents a design method in small-scale RC structural shaking table test, similitude harmony design method. That is to adjust the reinforcement, cover thickness and stirrup space in the model to reach the harmony between concrete and reinforcement. We create models use similitude harmony design method and commonly used design method respectively, and study the similarity error by component test, shaking table test and numerical simulation. In this way, we verify the effectiveness, rationality and feasibility of this method.(2)Step loading is usually used in small-scale RC structural model shaking table test. According to this, we propose the classified similitude relation. By reference the test result of natural frequency after one step and relationship between natural frequency and elastic modulus, we change the elastic modulus ratio to adjust the similarity relation, and then apply the next step's loads to simulate the response behavior of the prototype structural. By small-scale RC structural model test result and simulation result of prototype structural, we study the similarity error between model designed according to classified similitude relation and model not designed according to this. Also we study its improvement to the error caused by gradually loading.