The Mechanical Properties After Fire Of Prestressed SRC Beams

The combination of modern technology in prestressing and SRC structure reinforeces the SRC structure's advantage, and also relarge the scale of the application for a longer span and more load. So, the prestressed SRC structure can be used to long-span construction, heavy-Loaded-structure, tall building and transfer structure in high-rise Buildings. Experiments are carried out to determine the high-temperature mechanical properties of pre-stressed concrete simple-supported beam. It investigates the main factors influencing properties of pre-stressed concrete beam and analyzes the degradation of the beam's mechanical performance in the high tempreture. The main contents of the results of research are as following:1. By means of finite element analysis software ABAQUS, it analyzes the heat transfer process of the pre-stressed concrete in the international standard temperature-time curve and gets the temperature field's distribution map of the pre-stressed concrete simple-supported beam in the time of 30min,60min,90min,120min,150min, 180min, which are compared with the test results.2. Taking into account of the fire duration time, the beam's fire-resistant tests in the Structure laboratory of the Shandong Jianzhu university analyzes the rules of bearing capacity of pre-stressed concrete simple-supported beam and reveals the degradation of the beam's mechanical performance in the high tempreture.3. Through comparating the results that the beams are applied by two concentrated loads at ordinary temperatures and high temperatures, it reveals the distribution and development of the cracks, the change rules of the vertical deflection and the variation of bearing capacity of the beams.4. Based on the effective section method, it puts forwards the formula of the flexural carrying capacity of the pre-stressed concrete beam after the fire,which the results agree well with the tested ones.