| Under gravity loads and lateral seismic load, the slab-column connections must undertake the large unbalanced moment in addition to the punching shear caused by gravity loads, the seismic design of connections is very important. In foreign countries, such as the United States, the slab-column frame can be used as lateral force resistant system in low-intensity earthquake regions, a lot of researches of the behavior of slab-column connections under the combined action of punching shear and unbalanced moment, the seismic design requirements are proposed. The study on seismic behavior and design method of slab-column connections are proceeded to suffice for the domestic demands of design of slab-column frame structures, the main results of the study are listed as below:1. On the basis of the analysis of the collected experimental data of domestic and foreign researchers with the linear regression method, the correlative curve with 95% guaranteed rate of the inter-story drift ratio and the ratio of punching shear to nominal shear strength of punching critical section(V_g/V_u) of reinforced and prestressed concrete slab-column structure is obtained. The upper limits of V_g/V_u of slab-column connections without punching shear reinforcement correspond to 1/50 and 1/100 inter-story drift ratio are recommended, for those checking calculation ofseismic elastic-plastic deformation can be omitted.2. Seismic design method of slab-column connections is proposed, in which enlarged factors 1.65 or 1.5 is recommended for the design value of unbalanced moment of slab-column connections for aseismic grade one or aseismic grade two respectively.3. A simplified method for calculation of elastic-plastic inter-story drift ratio of slab-column structure is proposed, and it coincides well with the results by push-over method.4. The seismic design method of slab-column connections proposed in this thesis is applicable. |
