钢筋砼粘结锚固性能的试验研究

通过钢筋与混凝土拉式粘结试验，测试了高强度带肋钢筋与不同强度等级混凝土的粘结强度，分析了带肋钢筋与混凝土的粘结受力机理；采用双线性软化本构对开裂区的软化行为进行描述，建立了综合考虑开裂区及未开裂区混凝土影响的粘结强度理论计算模型；研究了开裂区不同径向位移分布对计算结果的影响，并将计算结果与试验结果进行对比，验证了计算模型的有效性。
结果表明：模型采用基于等效弹性假设的开裂区径向位移分布时，计算值与试验值最为吻合，但却过高的估计了低强度混凝土试件的粘结强度；为确保有足够的安全储备，建议采用弹性假设作为开裂区混凝土径向位移分布。

Experimental research on bonding and anchoring performance of reinforced concrete

The bond strength between high-strength rebars and concrete with different strengths was tested by pull-out tests. The bonding mechanism between rebars and concrete was analyzed. The bilinear softening constitutive model was used to describe the softening behavior of concrete in the cracked zone, and the theoretical calculation model of the bond strength considering the influence of concrete in cracked and non-cracking zones were established. The effects of different radial displacement distributions in the cracked zone on the calculation results are studied.
The validity of the calculation model was verified by comparing the calculated results with the experimental results. The results show that the computational model has the best accuracy when the radial displacement distribution in the fracture zone is assumed to be equivalently elastic. However, the bond strength of low-strength concrete specimens was overestimated under this assumption. It is suggested that the elastic assumption be used as the radial displacement distribution of concrete in the cracked zone to ensure adequate safety reserves.