CONSTRUCTION ANALYSIS OF REINFORCED CONCRETE BRIDGE PIER

In this study, the construction of a reinforced concrete bridge pier is analyzed from durability point of view. The bridge is located at the western port area of Shenzhen, where the climate is high temperature and humidity. To control the cracking of concrete, a heat transfer problem as well as a thermal stress problem has to be solved. A shrinkage model for heat produced due to cement hydration and a Burger constitutive model to simulate the creep effect are used. The shrinkage due to the hygral and the plastic is considered. The modelling based on Femmasse (c) is verified by comparing with the testing results of a real underground abutment. For the bridge pier, the temperature and stress distribution, as well as their evolution with time are shown. To simulate the construction condition, four initial concrete temperatures (5 degrees C, 10 degrees C, 15 degrees C, 20 degrees C) and three demoulding time tips (48h, 72h, 96h) are investigated. From the results, it is concluded that a high initial concrete temperature could result in a high extreme internal temperature, which causes the early peak temperature and the larger principle stresses. The demoulding time seems to be less important for the chosen study cases. Currently used 72 hours in the construction practice may be a reasonable choice.