高强钢筋混凝土桥墩抗震性能试验研究与分析

EXPERIMENTAL STUDY AND ANALYSIS ON ASEISMIC PERFORMANCE OF HIGH STRENGTH REINFORCEMENT CONCRETE BRIDGE PIERS

通过拟静力试验研究配置高强钢筋混凝土桥墩的抗震性能。分析桥墩试件的破坏形态,对往复荷载作用下桥墩试件的滞回特性、承载能力、延性性能、耗能能力等抗震性能指标进行比较研究。分析轴压比、剪跨比、箍筋间距及钢筋强度等对抗震性能的影响规律。研究表明:配置高强钢筋混凝土桥墩试件的破坏形态与配置普通钢筋的混凝土桥墩的一致,剪跨比较小的桥墩变形能力有限,呈弯剪破坏形态;剪跨比较大的桥墩变形能力较大,呈弯曲破坏形态。提高轴压比虽能提高试件的承载能力,但使其抗震性能指标降低,不利于桥墩抗震。提高钢筋强度和加密箍筋能提高其各方面的抗震性能指标,有利于结构抗震。

Aseismic performance of high-strength steel-bar-concrete-bridge piers designed is verified by quasi-static test. The damage characteristic of bridge piers was analyzed. The hysteretic characteristic, bearing capacity, ductility performance and energy dissipation were investigated. The effect of different improvement measures on aseismic behavior in terms of axial compression ratio, shear span ratio, stirrup space and reinforcement strength grade were analyzed. The results show that the damage behavior of concrete bridge piers with high strength reinforcement are similar to those with conventional stirrup. With a finite deformation, the small shear-span-ratio bridge-piers suffered flexural-shear failure models while the large shear-span-ratio one suffered flexural failure models and possessed large deformations. The bearing capacity of bridge piers is enhanced while the other aseismic index performance become low with the increased of axial compression ratio, which is disadvantage of aseismic performance of bridge piers. The more the reinforcement strength grade and stirrup ratio are, the better the aseismic performance is. Therefore, it is better for aseismic performance of bridge piers.