The Test Analysis On The Comprehensive Seismic Resistant Behaviors Of The Long-span Pre-stressed Concrete Hypo-beam Floor System

Through the analysis of the two test results of the space model specimens of the Long-span Pre-stressed concrete hypo-beam floor system, the thesis discuss the seismic resistant behaviors of the structure system under horizontal force. The thesis explores that problem from three factors that are the internal-force redistributing law of the structure system under period iterative load and the seismic resistant behaviors of the space joints of the structure system, as well as the influence on the seismic resistant caused by the distance between the columns.The two specimens, which are designed as: main beam-pre-stress beam—floor—frame columniation assemble the space specimens. In order to checkout whether the code can be applied for the special structure systems, the structure of the specimens refer to the current GB50010-2002 concrete structure design code and GB50011-2001 seismic resistant code. The detection methods, load procedure and selecting the sample of material, etc. all be done by the request of the "test on the building structure" strictly.From the test and study the following conclusions are reached 1. The behaviors under seismic horizontal force are very different between the hypo-beams through joint and not. The passed-joint hypo-beam as the first line of defence organization against horizontal force ineluctably bear most curves during the first period under the seismic force, which can't be balanced by the pre-stressing force of the pre-stressed hypo-beam, therefore, the first crack will occur on it's end and at last develop into the plastic-hinge. If the ordinary top longitudinal steel bars of the passed-joint hypo-beam yield, the yield will penetrate into the joint area and the slip of bar anchorage is much worse than the ordinary frame joint. Meanwhile, the rotational capability of the plastic hinge on the end of the passed-joint hypo-beam determine the capability of dissipation earthquake energy and occurrence of the process of internal force redistributing in the last period under earthquake force of the structure system in this test.The conclusion that the torsion of main-beam can improve the earthquake resistant behaviors of the beam-to-column joints can be reached from the results of the test and other people's studies. The earthquake resistant behaviors of the beam-to-column joints can't be weaken by the resistant2. mechanism under the action of moment, shear and torsion. Meanwhile, if there isn't the passing-joint hypo-beam on the column, it will occur another destroying style such as the middle joint of the second specimen3. It is very important that the influence on the seismic resistant of the whole structure caused by the torsion resistant capability and the turn capability of torsion plastic ream in the end of beam. Therefore the design of torsion resistant should be noticed in engineering design.4. The construct method and require of the column joint of frame beam in the current design code can be still used in this structure system: passing-jiont hypo-beam—main beam—column joint. The anchor length of longitudinal steel bars of the main beam can be designed according to frame beam, otherwise, he hoop steel bars can be lay in the joint if it don't raise the construction difficulty.