Experimental Study On Mechanics Performance And Numerical Simulation Of Bamboo Tubes

Bamboo tubes are a kind of anisotropic material whose mechanical properties along the transverse axes are far less than axial.The failure of bamboo tubes often occur under the transverse concentrated force in structural application.In order to make full use of bamboo,this paper conducts experimental analysis and numerical simulation of bamboo pipes' edge bearing capacity,and conducts experimental research on connections in a space grid structure.It is shown in the failure experiments of the bamboo tubes with and without joints form the Anji County that the edge bearing capacity can increase about 50%because the supporting effect of joints on bamboo tubes.Exploring the reinforcement technology of bamboo tubes' edge bearing capacity,and then conducting the failure tests of bamboo specimens reinforced by the "internal filling " and "external wall using hose clamps".It is found that "internal filling" can significantly improve the bearing capacity of the bamboo tubes,while the "external wall using hose clamps"can prevent crack propagation after the crack appears.This article proposed hierarchical model and computing method of bamboo tubes' edge bearing test.The analog values of bearing capacity and the initial crack's position of short tubes with joints,long tubes without joints and long tube with joints are well matched with the test value,which prove that the finite element method and parameter values have great computational accuracy.The bending test of single tube was completed by distributive girder,and the longitudinal elastic modulus of bamboo was calculated based on the simply supported beam model of experiment.Since bamboo tubes are often combined into bundles in bamboo construction,the bending test of the bundles is carried out by the distributive girder.However,all multiple bamboo tube bundles were found to be failed in local crushing at mount point,this article proposed a multi-point loading device for bamboo bundles.The writer contrasted and analyzed the failure characteristics and bearing capacity of single tube and bundles.The characteristics of the spatial grid structure are summarized,and the strengths and weaknesses of existing connection forms of bamboo tube triangular in the structure are analyzed.Aiming at the mechanical properties of the steel bar-grouting junction in application,the bending test of butt-joint which is the most unfavorable situation was completed.The edge bearing test was conducted to analyze the influence of carbonization and high-temperature cooking on the mechanical properties of the structural bamboo tubes.The simplified bearing model was used to measure the bearing capacity of the bamboo tubes between the bamboo tube triangular,and the designed bearing capacity of the bamboo tubes was obtained.