Studies On The Environmental Simulation Test Scheme Of Concrete Bridge Structures And The Loading Device

The durability problem caused by concrete deterioration has brought unprecedented challenges to the whole world.In recent years,many domestic and foreign scholars have done a lot of research work from the macro and micro aspects of concrete,in order to predict the service life of concrete and improve the durability of concrete.The experiment is the basic and important method to study the durability of concrete.However,there has not yet formed a unified standard about the durability test method of concrete bridge structure at aspect.And in the durability tests on concrete,mostly are about the durability of the material,few are about multi-factor erosion coupled condition based on the real service environment and load characteristics of the bridge structures.Based on the applied basic research project of Ministry of Transport(2013 319 812 100),this paper studies the environmental simulation test scheme of concrete bridge structures.According to the real service environment of the bridge structure,the durability disease of the concrete bridge structure in China could be classified into two categories: the northern freezing and thawing damage and the southern rust damage which are based on the systematic investigation of the disease characteristics and damage mechanism,meanwhile,the northern and southern disease environment model are established by taking the typical city as an example.With the similarity theory,it is proposed that there should be four aspects of similarity between the simulation test and the real environment.At the same time,the basis of the environmental simulation test plan is given.Then,from the aspects of functional design,layout design and index parameter design,the general situation of structural climate and environment simulation laboratory construction are introduced.The main functions,such as salt fog,rain,carbonization and so on,are shown by flow charts.The standard specimens for the test are designed based on the basis.The loading devices for the column and beam specimens are designed by analyzing the specimens loading characteristic.Finally,according to the durability factors of the two disease environment models and the settings of environmental parameter in accelerated test both in china and abroad,the northern and southern for multi-factor coupling environment simulation of bridge structure are proposed and the test steps are described in detail.It is believed that the research could unify the test scheme of bridge durability and have some significance in promoting the study of the durability of concrete bridge.