深受弯构件抗剪影响参数显著性分析

SIGNIFICANCE ANALYSIS OF INFLUENCE PARAMETERS ON SHEAR CAPACITY OF DEEP FLEXURAL MEMBER

为合理量化不同规范中深受弯构件抗剪影响参数的显著性,结合691组受剪试验数据,通过相关分析系统地研究了单因素、组合因素对其抗剪能力影响的显著性,采用Kendall相关系数、Spearman相关系数和偏相关系数进行量化评估,并利用主成分分析法给出四项综合指标,分析各指标对实际受剪承载力的影响比重。研究表明:单因素条件下,混凝土强度等级fc'对受剪承载力影响较为显著,截面尺寸b和h0,剪跨比a/h_0次之;组合因素下,fc'、bh_0、ab、a/h_0对受剪承载力影响较显著。同时,由主成因素分析得到的四项综合指标对深受弯构件受剪能力贡献比重依次为31%、16%、13%、9%,为深受弯构件的抗剪设计提供理论参考。

Based on code provisions, this paper collected 691 test results to reasonably quantify the significant influence parameters on the shear capacity of deep flexural members. Through correlation analysis, single influence parameters and combination factors are quantifiably evaluated by Kendall, Spearman and Partial Correlation coefficients. Four comprehensive indexes are integrated by principal component analysis to analyze the contribution ratio of actual shear capacity. The results show that：for a single influence parameter, the most significant factor is cylinder concrete strength fc＇, section size h0 and b, and the shear-span ratio a/h0 are also significant. For combination factors, the influences of fc＇, bh0, ab and a/h0 on shear capacity are more important. The contribution ratios of four comprehensive indexes using principal component analysis are 31%, 16%, 13% and 9%, respectively. The research provides a theoretical reference for the shear design of deep flexural members.