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.