THE LOSS OF LOAD-TRANSFER CAPACITY AT JOINTS OF AIRFIELD CONCRETE PAVEMENTS UNDER REPETITIVE LOAD

Abstract

Joints are the weak parts of the airfield concrete pavement structure. When joints are working in better state, they have a fairly high capacity of load transfer. Generally, the load transfer capacity decreases with the increase number of repetition of loads, which leads to the loss of design bearing capacity of pavement. This process is called the loss of load transfer capacity. of joint. This may result the increase of edge stress and then the edge cracks, pumping. Then loss of support will appear. It is important to study deeply the loss of load- transfer capacity for several joints types under repetitive loads, and this is very important for improving the performance and durbility of concrete pavement of airfield. For this purpose, Transportaion Research Institute of Southeast University and China Airport construction company, Guangzhou Branch have made an experimental pavement which has five types of joints and is constructed in circular track road test platform in laboratory of Southeast University. The Falling Weight Deflectometer (FWD) is used to measure the loss of load transfer capacity of joint under loads. Through test and analysis, we have found the relationships of the loss of load transfer capacity of joints and the edge displacement with the loading repctetition numbers. And also the analysis indicates that the dowelled joint and the engaged joint are the best types of joints among the five.