纵肋大开洞预应力混凝土双T板受力性能分析

Mechanical Property Analysis of Prestressed Concrete Double Tees with Large Web Openings

工业上楼的兴起对传统厂房结构构件和建造技术提出了新挑战。预应力混凝土双T板是最常用的预制预应力构件之一,具有自重较小、经济高效等优势。然而由于现代厂房设备管线布置的系统性和复杂性,一般需在其纵肋大开洞。结合开洞梁设计理论,提出一种新式楼盖构造,即纵肋大开洞双T板,给出相应设计方法和补强措施,并采用有限元模型对其受力性能进行对比分析。计算结果表明,经过设计补强处理后的开洞双T板构件应力和变形均满足规范要求,且与未开洞普通双T板相比,设计参数并未表现出明显差别,整体承载力基本不受影响,表明纵肋开洞补强受力安全,技术可行。随着洞口数量和长度等开洞参数的增加,双T板构件的整体初始刚度呈现出不同程度削弱,需在设计中予以注意。

Today a new challenge is proposed for structural members and constructional technologies of traditional factory by the growing up for high⁃rise industrial plant.Prestressed concrete double tees(PCDT),which has several performance advantages such as lighter self⁃weight and more economical and efficient,is one of the most commonly used prestressed concrete components.However,it is need to open rectangular holes in its web as systemic and complex layout of pipeline equipment in modern workshop.A new type floor details called PCDT with large web openings is presented based on design theory of prestressed concrete beams with openings.Then its design method and reinforcement measure are given,and comparative analysis is conducted by corresponding finite element model.Numerical results show that both stress and deformation values of PCDT with large web openings meet relevant code’s requirements after strengthening.There is little difference on design parameter and overall bearing capacity between PCDT with or without large web openings.As a result,it is safe and feasible on mechanical properties for reinforcing PCDT with large web openings.In addition,it should be noted in design process that integral initial stiffness of PCDT will be reduced with different degrees by the increase in numbers or lengths of its web openings.