基于ECC裹覆钢丝网的复合加固技术抗弯试验研究

Study on Bending Resistance Test of Composite Reinforcement Technology Based on ECC Wrapped Steel Wire Mesh

本文提出基于水泥基纤维混凝土(简称:ECC)裹覆钢丝网的复合加固技术,首先对水泥基纤维混凝土进行了改良设计,开展了相关性能试验;其次,介绍了ECC裹覆钢丝网的复合加固技术的原理和锚固、张拉特点。借助设计ECC裹覆钢丝网的复合加固技术抗弯加固试验,测试和研究了该技术的可靠性以及加固前后梁体的性能参数。试验结果表明:选用玄武岩纤维的水泥基纤维混凝土具有很高的化学稳定性、抗拉伸强度高、抗老化性,可以有效改善混凝土结构的耐久性问题;水泥基纤维混凝土表现出明显的塑性破坏特征,并具有应变硬化与多重开裂特征,极限拉应变有明显提高;ECC裹覆钢丝网的复合加固技术能够有效提高试验的开裂荷载、屈服荷载和极限承载力。预应力钢丝从镦头到锚固全过程性能良好、安全可靠,锚固板在梁体发生破坏时仍能良好工作。

In this paper,the composite reinforcement technology based on cement-based fiber concrete(ECC)wrapped steel wire mesh is proposed.First,the improved design of cement-based fiber concrete is carried out,and the related performance tests are carried out.Secondly,the principle of composite reinforcement technology of ECC wrapped steel wire mesh and the characteristics of anchorage and tension are introduced.The reliability of the technology and the performance parameters of the beam before and after reinforcement are tested and studied by means of the flexural reinforcement test of the composite reinforcement technology with ECC wrapped steel wire mesh.The test results show that the basalt fiber cement-based fiber concrete has high chemical stability,high tensile strength and aging resistance,which can effectively improve the durability of concrete structure.Cement-based fiber concrete shows obvious plastic failure characteristics,strain hardening and multiple cracking characteristics,and the ultimate tensile strain is obviously increased.The composite reinforcement technology of ECC coated steel wire mesh can effectively improve the cracking load,yield load and ultimate bearing capacity of the test.The performance of the prestressed steel wire from heading to anchoring is good,safe and reliable,and the anchoring plate can still work well when the beam body is damaged.