Study On Anti-lateral Performance Of Bamboo Frame Withdiagonal Prestressed Cable

At present,China commit to promote green building materials,fabricated modern wooden structure.Bamboo frame has high degree of prefabrication and convenient construction,meet the national architectural policy of "applicable,economic,green,beautiful".The experiment and earthquake experience show that:the anti-lateral performance of the traditional bamboo frame is not enough,prone to collapse in the earthquake.Therefore,this group has proposed the structure of a diagonal prestressed bamboo frame to overcome the shortcoming of anti-lateral performance of traditional bamboo frame.There is little research on the whole reinforcement of bamboo frame by prestressed cable,Therefore,it is necessary to study the stress characteristics of bamboo frame under the reinforcement of prestressed cable.This paper starts with the finite element analysis,on the basis of a comprehensive understanding of the stress characteristics of the diagonal prestressed bamboo frame,gives the design method of the diagonal prestressed bamboo frame.The key problems in the elastic-plastic design method of bamboo frame based on strength are discussed.Finally,the seismic vulnerability analysis of the diagonal prestressed bamboo frame was carried out.The main contents and conclusions are as follows:(1)The finite element analysis was carried out on bamboo frame with diagonal prestressed cable.Adopt the method of modeling the three-dimensional entity refinement and result is consistent with actual stress state.The pinch of the hysteresis curve is caused by the slip of the bolt connection.The results shows that the prestressed cable can significantly improve the stiffness of bamboo frame.Finally,the influence of the prestress size and the cross-sectional area of the cable on the lateral resistance of the frame is analyzed.(2)The stiffness calculation formula of the diagonal prestressed bamboo frame is deduced.the design method of cable cross-sectional area and prestress size is given,and the correctness of the design method is verified by a example.(3)The characteristics of the elastic-plastic design method of bamboo frame based on strength are analyzed.The strength reduction factor of the bamboo frame in the elastic-plastic design method is calculated by the example,the relationship between the strength reduction coefficient and the related parameters of ordinary frame and bamboo frame with diagonal prestressed cable was compared.(4)The probabilistic earthquake demand curve and seismic vulnerability curve of the bamboo frame with diagonal prestressed cable are given by choosing the corresponding performance standard.The results shows that diagonal prestressed cable can reduce the probability of transcending each performance state of bamboo frame,and obviously reduce the probability of collapse of the frame under large earthquakes.