Water Resistance Of Bamboo Component And Monitoring And Evaluation Of Structural State On Bamboo Bridge

This paper relies on the major project of the national forestry public welfare research projects, which is research and demonstration of key technology for construction of large span bamboo engineering(201204701).In the 21 st century, Under the background of "low-carbon, environmentally friendly, economical and sustainable development", with the depth and perfection of the reconstituted bamboo technology, extensive source of the bamboo, and the outstanding advantage of its light weight, high strength, good toughness, environmental protection, etc. Modern bamboo bridge will be widely built, applies not only to the pedestrian and landscape bridge, and also partly applies to the dealers bridge, has been an unprecedented development. However, the research of monitoring and evaluation on bamboo(wood) bridge is initial stage, this paper has important research significance and the necessity.This paper studies the water resistance of recombinant bamboo components(shear, bending and compressive specimens) and the influence of strength, stiffness for Interlaminar adhesive cracking of beam, and on this basis, combined with the specific characteristics of a Fengdu bamboo bridge, established a monitoring and evaluation system of the bridge, discussed the selection, collection and evaluation of monitoring indicators in the monitoring system, Using comprehensive evaluation method of AHPVariable Weight Theory to assess the structural state levels, providing the basis for custody decisions. In this paper, the main research is as follows:①Taking the component of recombinant bamboo as the research object, studied the water resistance test of shear, compressive and bending components, analysis failure mode of them, obtain the moisture absorbent equation with soaking time, and the water resistance decay equation of the mechanical properties with soaking time or moisture.②Interlaminar adhesive cracking is one of the main defects of reconstituted Bamboo lumber. Using the large-scale general finite element software ABAQUS to simulate that 10 kinds of adhesive cracking form make an effect on flexural bamboo beam, resulting in different locations in different lengths of plastic cracking attenuation of its strength, stiffness and load capacity.③Based on the concept and related criterion of monitoring system and sensor, established monitoring system of the bamboo bridge structure, proposed the method of data acquisition, classified and evaluated the monitoring indicators, which can not be directly assessed should selected appropriate function by dimensionless processing. According to the service environment and the structure features of a Fengdu bamboo bridge, identified several on-site monitoring projects.④Based on the comprehensive assessment framework of AHP- variable weight theory, established a hierarchy structure model of the condition assessment in Fengdu bamboo bridge, using variable weight theory, as a whole reflect the work status of all components, especially the smaller weight components, namely the secondary member, making the evaluation results more realistic, more reasonable.