提升结构抗力的拱桥加固技术新方法研究

Research on New Methods of Arch Bridge Reinforcement Technology for Structural Resistance Enhancement

一般的拱桥设计主要考虑让主拱圈在恒载作用下,及恒载与主要活载的组合荷载下,拱轴线与拱轴压力线重合(五点重合法),但是由于交通量不断增加,长期运营过程中,活载不断增加导致拱轴线与压力线出现偏移,这便是导致拱桥损伤的主要因素,其外观特征体现在拱圈部位和拱上建筑会出现不同程度的损坏,在严重损坏的情况下不能满足结构的安全使用性能。该文以207国道岑溪市水汶镇内的水汶大桥为依托,采用现场调查和收集相关文献资料等方法,就当前主拱圈病害尚不明显、承载能力能够满足基本需求的圬工拱桥状况进行了系统分析,并结合实际将传统拱桥加固方法进行融合创新。针对主拱圈病害尚不明显的圬工拱桥,应尽量从克服其主要影响因素方面出发,从根本上解决问题,恢复因长期运营过程中活载不断增加导致拱轴线与压力线出现的偏移,让主拱圈在恒载作用下及恒载与主要活载的组合荷载下拱轴线与拱轴压力线再次重合,从而有效解决拱桥主体结构损伤问题,使加固后结构的长期可靠性得到保证。针对薄弱构件采取加固补强措施,能够提升结构整体安全使用性能,经济效益效果显著。

The general design of an arch bridge mainly considers that the arch axis and the arch axis pressure line coincide (in 5 points) under the action of the main arch ring and the combined dead load and the main live load. However, due to the increasing traffic volume, the live load is increasing during the long-term operation, causing the arch axis to deviate from the pressure line, which largely contributes to arch damages. Its appearance characteristics are reflected in the arch ring and the arched building will show different degrees of damage, and it can not meet the safety performance of the structure in the case of severe damage. Based on the Shuiwen Bridge in Shuiwen Town of Cenxi City on National Highway 207, this paper systematically analyzes the condition of masonry arch bridge that the main arch ring disease is not obvious and the bearing capacity can meet the basic requirements by means of field investigation and literature summarization, and combines the traditional arch bridge reinforcement methods with the actual situation to carry on the fusion innovation. For the masonry arch bridge with no obvious disease in the main arch ring, the main influencing factors should be overcome to fundamentally solve the problem and restore the deviation of the arch axis and the pressure line caused by the continuous increase of live load during the long-term operation, making the arch axis and the arch pressure line of the main arch ring coincide again under dead load and combined dead load and the main live load, effectively solving the damage problem of the main structure of the arch bridge and ensuring the long-term reliability of the reinforced structure. Reinforcing the weak members can improve the overall safety performance of the structure, with remarkable economic benefits.