预张拉纤维布约束混凝土圆柱预应力损失试验

Experimental Research on Pre stress Loss of Concrete Circular Columns Confined with Post tensioned FRP

摘要:

为了对混凝土墩柱有效施加环向预应力，研制了一种自锁式锚具用来环向张拉纤维布，从而对核心混凝土提供主动约束应力，提高混凝土墩柱的强度和延性.根据自锁式锚具的施工工艺，分析了引起预应力损失的主要原因，针对摩擦损失、碳纤维布应力松弛损失、混凝土收缩徐变损失等各种影响因素进行了试验研究和理论分析，得到了各项预应力损失的发展规律及其与相关影响因素的关系，提出了减少预应力损失的措施.

Abstract:

A new self locking anchor (SLA) is proposed in order to apply the lateral pre stress to the concrete columns. By using this device, the lateral fiber reinforced polymer (FRP) sheets can be post tensioned effectively so that the core concrete can be actively confined. Then the strength and ductility of concrete columns can be highly enhanced and strengthened with lateral pre stressed FRP sheets, and the strength of FRP can be fully used. According to the construction process of SLA, the major reason for the lateral pre stress loss is analyzed. Based on the experimental research and theory analysis, including the friction loss，carbon fiber reinforced polymer(CFRP) relaxation loss，concrete creep loss and other factors, various discipline and related relationship are found. Finally, proposals to reduce the lateral pre stress loss are put forward.