混凝土柱“强剪弱弯”设计可靠度对随机变量的敏感度分析

研究了在地震作用下钢筋混凝土柱“强剪弱弯”设计可靠度及其对随机变量的敏感度分析方法计算了在不同的柱截面尺寸、不同的配筋率与配箍率、不同的剪切增强系数时柱“强剪弱弯”设计可靠度指标与敏感度指标。结果表明:柱“强剪弱弯”设计可靠度指标对抗剪计算模式、混凝土抗拉强度十分敏感,规范所采用的剪切增强系数难以保证“强剪弱弯”设计可靠度。因此,现行《混凝土结构设计规范》(GB50010-2002)所采用的抗剪设计公式需要进一步完善,剪切增强系数应该适当提高,同时,混凝土抗拉强度的统计参数提供要相对精确。

SENSITIVITY ANALYSIS ON RANDOM VARIABLES OF STRONG SHEAR WEAK BENDING DESIGN RELIABILITY OF RC COLUMN

The strong shear weak bending design reliability of RC column and sensitivity thereof on random variables under earthquake action are calculated. The influence of section dimensions, reinforcements areas and hoop reinforcements areas and shear-enlarged coefficients on reliability and sensitivity thereof is investigated. The results indicate that strong shear weak bending design reliability, which can′t be ensured by shear-enlarged coefficients taken in the current design code, is very sensitive on calculating model of shear-resistance and concrete fiexural strength. So the calculating model of shear-resistance taken in the current design code is necessary to be perfected and the statistical characters of concrete flexural strength should be more accurate.