型钢轻骨料混凝土粘结滑移本构关系研究

本文研究了型钢与轻骨料混凝土的局部粘结滑移本构关系. 在型钢表面刻槽贴应变片,并在与型钢应变片对应位置的混凝土表面贴应变片,由试验结果和分析：得到了型钢表面粘结应力沿锚固长度的负指数分布函数;绘制了局部滑移分布曲线;给出了加载端局部粘结滑移本构关系. 局部最大粘结应力主要与混凝土强度、配箍率、混凝土相对保护层厚度有关. 引入粘结滑移本构关系的型钢轻骨料混凝土梁有限元分析结果和试验结果吻合较好.

THE BOND STRESS-SLIP RELATIONSHIP FOR STEEL REINFORCED LIGHTWEIGHT CONCRETE

The bond-slip constitutive relationship is studied based on the push-out tests of nine steel reinforced lightweight concrete specimens. The section steel is instrumented with strain gauges in a machined axial cavity at the flanges and webs, and gauges are also stuck on the concrete surface corresponding to the gauge positions of the section steel. According to the test results, the negative exponent distribution function of the bond stress along the anchorage length is analyzed and the local relative slip curves are obtained. The constitutive relationship between the local bond stress and the slip at the loading end is investigated. The maximum local bond stress mainly depends on the strength of the concrete, the stirrup ratio and and concrete cover depth. The steel reinforced lightweight aggregate concrete beams are analyzed through introducing the local bond-slip constitutive relationship. The test values agree very well with those obtained with finite element analysis.