CFRP预应力筋夹片式锚具的试验研究  

Experimental investigation of wedge-type anchors for CFRP tendons

作　　者：蒋田勇[1] 方志[1] 

机构地区：[1]湖南大学,湖南长沙410082

出　　处：《土木工程学报》2008年第2期60-69,共10页China Civil Engineering Journal

基　　金：国家自然科学基金(50478052);教育部优秀青年师资助计划项目

摘　　要：传统的夹片式锚具应用于CFRP(Carbon Fiber Reinforced Polymer/Plastics)预应力筋时必须进行改进,改进后的夹片式锚具由凹齿曲面的夹片、锚杯、塑料薄膜以及薄壁铝套管等组成。在夹片式锚具设计过程中,首先通过锚具的静力分析,推导锚杯的应力公式,然后根据VonMises屈服准则确定锚杯的最小厚度,再由锚杯和夹片的几何关系得到夹片的几何尺寸。试验研究表明,当锚杯倾角为3°、夹片预紧力为100kN、铝片厚度为1mm、凹齿间距为12.85mm和凹齿深度为0.3mm时,夹片式锚具表现出较好的锚固性能,极限荷载达到了185kN,相应的锚固效率系数为96.4%。锚杯长度、锚杯倾角、夹片预紧力、凹齿间距、深度和宽度以及铝套管的厚度等试验参数,均对夹片式锚具的极限承载力及CFRP筋和夹片之间的滑移量有较大影响。锚杯应力的实测值与理论值吻合良好,验证了锚具应力分析的可靠性。极限荷载的计算式具有较好的适用性。The conventional wedge-type anchorage system for steel tendons must be improved for CFRP （Carbon Fiber Reinforced Polymer/Plastics） tendons. Wedge-type anchors for CFRP tendons have been developed by assembling smooth indented wedge, conical barrel, plastic film, and aluminum soft metal sleeve. Based on the mechanical behavior of wedge-type anchors, the stresses of conical barrel are derived, and the minimum thickness of conical barrel is obtained according to the Von Mises yield criterion. The dimensions of the wedges can be obtained from the geometric relationship between the conical barrel and the wedge. The static tests indicate that, when the anchor involves a 3^-conical barrel, a 100kN of presetting load, a 1.0 mm thick aluminum soft metal sleeve, a 12.85 mm space and 0.3 mm deep indented wedges, the anchorage system can perform well and undertake an ultimate capacity of 185kN with an anchorage efficiency of 96.4%. Factors that affect the anchorage performance and the slip of CFRP tendon are illustrated, including length and slope of conical barrel, presetting load level, space, depth and width of indented wedges, and thickness of aluminum sleeve. The good agreement between the analytical and experimental stresses of conical barrel validates the present approach. The equations developed for evaluating the ultimate load of the anchors are feasible.

关 键 词：CFRP 夹片 锚杯 锚具 

分 类 号：TU757.2[建筑科学—建筑技术科学]