论文部分内容阅读
目前我国预应力混凝土连续箱梁中间锚附近开裂现象比较普遍,已经严重影响了该类桥梁的安全性和耐久性。造成该问题的原因可能与我国混凝土应力非规则区域设计理论不成熟有关,我国目前混凝土设计规范多以平截面假定为基础进行设计,而中间锚区是严重的非规则区域,不符合平截面假定。以预应力混凝土连续箱梁中间锚为分析对象,首先进行局部应力分析得到局部区域主应力矢量图,在此基础上提出相应的拉—压杆设计模型,并进行中间锚固区配筋设计,该方法具有思路清晰明确,便于应用等优点。
At present, the phenomenon of cracking near the middle anchor of prestressed concrete continuous box girders in our country is relatively common, which has seriously affected the safety and durability of such bridges. The cause of this problem may be related to the immature design theory of irregular stress in concrete stress field in our country. At present, the design code of concrete in China is mostly based on the assumption of flat section, while the middle anchorage area is a serious irregular area, which does not fit the assumption of flat section . Taking the middle anchor of continuous box girder of prestressed concrete as the analysis object, local stress analysis is firstly carried out to get the principal stress vector diagram of local area. Based on this, a corresponding design model of tension-compression bar is proposed and the design of reinforcement in middle anchorage zone The method is clear and clear, easy to apply and so on.