Effects of Hoop in Steel and R/C Composite

本研究的主要结论如下：(1)提出的型钢混凝土‘钢’-‘混凝土’-‘箍筋’组合体系具有较好的抗震性能。(B)在受弯剪裂缝作用的型钢混凝土构件中，弯曲裂缝主要集中在临界截面，没有观察到弯剪裂缝。(C)箍筋改善了混凝土的抗压性能，并防止钢筋局部屈曲。(D)在各种荷载条件下，箍筋有助于提高构件的延性。(E)型钢混凝土受压构件的变形不仅与压应变有关，还与沿斜裂缝的滑移有关，并受H型钢本身存在的影响。型钢混凝土的压应力与变形的关系不能用混凝土和钢材的压力和变形之和来评价。(F)弯剪作用下构件临界截面处的最大弯矩大于弯曲作用下的最大弯矩。弯剪构件中混凝土的压应力-应变关系应受到相邻实体混凝土约束的影响。

The main conclusions of this study are as follows; (a) The proposed SRC system, 'steel' - 'concrete' - 'hoop reinforcement' composite has quite good aseismic performance. (b) Flexural cracks concentrated at the critical sections in the proposed SRC members subjected to bending-shear cracks, and flexural-shear cracks were not observed. (c) Hoop reinforcement improved the compressive behaviour of the concrete and protected the steel from local buckling. (d) Hoop reinforcement contributed to the ductility of members under various loading conditions. (e) Deformation of the SRC member under compression is due not only to compressive strain but also to slip along the inclined crack, and affected by the existance of the H-shaped steel itself. The relation between compressive force and deformation of SRC cannot be evaluated as the sum of those of concrete and steel. (f) The maximun moment carried at the critical sections of members under bending-shear were greater than those under bending. Compressive stress - strain relationship of concrete in the members under bending-shear should be affected by the restraint of thr neighbouring solid concrete.