锈蚀钢筋混凝土简支梁斜截面抗剪性能研究

锈蚀钢筋混凝土构件抗剪性能是迫切需要研究的问题,本文通过18根锈蚀钢筋混凝土简支梁和3根无锈蚀的普通钢筋混凝土对比梁的斜截面抗剪试验研究及理论分析,研究了不同剪跨比下箍筋锈蚀程度对钢筋混凝土简支梁斜截面变形、裂缝形成和开展、承载能力、破坏机理等方面的影响。试验结果表明:箍筋锈蚀使箍筋对混凝土的约束降低,斜面裂缝发展较快,从而削弱了斜裂缝两侧骨料之间的咬合作用;剪压区箍筋锈蚀所产生的锈胀裂缝对试验构件抗剪强度的影响很大;剪跨比决定了试验构件的破坏形态,箍筋锈蚀对破坏形态影响较小;箍筋锈蚀对试验构件斜截面承载能力有较大影响。本文在试验研究基础上,运用根据极限平衡理论,建立了锈蚀钢筋混凝土简支梁斜截面承载力计算模型。

The shear behavior of corroded simply supported reinforced concrete beam

The effect of corrosion of stirrups on shear strength of corroded re inforced concrete beam is an important problem that needs to be studied. In this paper, through the experiment of 18 corroded reinforced concrete beams and 3 un corroded reinforced concrete beams, the effects of corrosion rate of stirrups on deformation, crack forming and development, bearing capacity and failure mechanism of the inclined section of simply supported reinforced concrete beam were investigated. The test results s howed that: the corrosion of stirrups reduces the constraint of stirrups to conc rete; the grip action of aggregates at both sides of the crack are deteriorated as the diagonal crack develops rapidly; the influence of cracks in shear-compre ssion zone of concrete due to stirrup corrosion on shear strength of beam is qui te large; the failure mechanism of beam is determined by the shear-span ratio, rather than by the degree of stirrup corrosion; stirrup corrosion has significan t influence on the shear bearing capacity of the beam. Based on this research an d using the ultimate equilibrium theory, the calculation model of shear bearing capacity of corroded simply supported reinforced concrete beam is established.