低合金耐蚀钢筋粘结锚固性能试验研究

    摘要：为探究低合金耐蚀钢筋粘结锚固性能的影响因素，并提出锚固长度的设计建议，通过45个低合金耐蚀钢筋试件拉拔试验，统计回归分析了耐蚀钢筋的粘结强度表达式，基于临界锚固长度极限状态方程，提出耐蚀钢筋的临界锚固长度计算公式，并与GB 50010—2010（2015年版）锚固长度计算式进行对比。结果表明，低合金耐蚀钢筋的粘结锚固性能与相对保护层厚度、配箍率和混凝土强度正相关，与钢筋直径、相对锚固长度负相关，与钢筋强度无明显相关性；提出的耐蚀钢筋粘结强度计算公式与实测值吻合较好；耐蚀钢筋的锚固长度可采用拟合公式计算，出于工程安全设计考虑，低合金耐蚀钢筋的相对锚固长度可取0.14fy /ft。

    关键词：低合金耐蚀钢筋；粘结强度；临界锚固长度

    中图分类号：TU511.3+2        文献标识码：A        文章编号：1001-702X（2023）01-0019-05

 

Experimental study on bond-anchorage properties between concrete and low-alloy corrosion-resistant steel bars

ZHANG Xiaonian1，XU Qing1，2，XU Man1，YANG Xiao3

（1.Central Research Institute of Building and Construction Co. Ltd.，MCC Group，Beijing 100088，China；
2.Department of Civil Engineering，Tsinghua University，Beijing 100084，China；

3.China Architecture Design & Research Group，Beijing 100044，China）

    Abstract：In order to investigate the influencing factors of the bond-anchorage properties of low-alloy corrosion-resistant steel bars and to propose the recommendations of designing anchorage length，this paper analyzed the expression of bonding strength of corrosion-resistant steel bars by statistical regression through 45 low-alloy corrosion-resistant steel bars specimens pulling tests，and proposed the critical anchorage length calculation formula of corrosion-resistant steel bars based on the critical anchorage length limit state equation，and compared it with the calculation formula of anchorage length in GB 50010—2010（2015 edition）. The re-

sults show that the bond-anchorage properties of low-alloy corrosion-resistant steel bars are positively correlated with the relative protective layer thickness，stirrup ratio and concrete strength，negatively correlated with the diameter and relative anchorage length of the bars，and not significantly correlated with the strength of the steel bars；the proposed formula for calculating the bonding strength of corrosion-resistant steel bars is in good agreement with the measured values；the anchorage length of corrosion-resistant steel bars can be calculated by the fitted equation. For engineering safety design consideration，the relative anchorage length of low-alloy corrosion-resistant steel can be taken as 0.14fy /ft according to the current specification.

    Key words：corrosion-resistant reinforcing bar，bond strength，critical anchorage length