超长混凝土结构收缩徐变机理及抗裂技术研究

Study on Shrinkage Creep Mechanism and Anti-Crack Technology of Ultra-Long Concrete Structure

文章以超长混凝土结构为主要研究对象,首先阐述了混凝土收缩、徐变机理及与开裂的内在联系,基于规范和文献中提供的最大裂缝宽度计算公式对预应力混凝土裂缝宽度计算方法进行了归纳,并对超长混凝土地下结构的抗裂技术进行了研究。结果表明,施加预应力可有效减小钢筋混凝土结构的裂缝宽度。通过结构底板与垫层之间铺设薄膜滑动层与底板施加预应力相结合的措施,解决了不设缝地下结构工程底板开裂的问题,并有效降低投资成本,为超长混凝土结构的抗裂技术提供了一种解决方案。

This paper takes ultra-long concrete structure as the main research object.Firstly,it elaborates on the internal relationship between the shrinkage and creep mechanism and crack of the concrete.Then it summarizes the calculation method of crack width of prestressed concrete based on the maximum crack width calculation formula provided in specifications and literature,and studies the anti-crack technology of ultra-long concrete underground structure.The results show that the prestress can effectively reduce the crack width of reinforced concrete structures.Through the combination of laying thin film sliding layer between the bottom plate and the cushion and applying prestress on the bottom plate,the problem of floor cracking in underground structure engineering without joint is solved,and the investment is effectively reduced,which provides a solution for anti-cracking technology of ultra-long concrete structures.