摘要
为研发适用于锚固碳纤维增强复合材料(CFRP)绞线的粘结式锚具,通过静载试验研究了CFRP绞线在超高性能活性粉末混凝土(RPC)中的粘结锚固性能,并基于试验结果提出了CFRP绞线在RPC中的合理锚固方式,建立了不同锚固体系的界面平均黏结强度和CFRP绞线临界锚固长度计算公式。结果表明:CFRP绞线在锚固段内的锚固布置方式对其锚固性能影响显著,将绞线在锚固段内打散后再进行单丝分散锚固可有效提高绞线的锚固效率;CFRP绞线中周围丝的扭曲形态有利于其与RPC的粘结锚固,但会使其抗拉强度有所降低;对于抗拉强度为2 470 MPa的CFRP绞线,其在抗压强度128.8 MPa的RPC中的临界锚固长度分别为120(中间单丝)、114(周围单丝)、106(分散锚固的绞线)、231mm(整束锚固的绞线);RPC中掺入体积不超过2%的钢纤维对CFRP绞线与RPC间粘结性能无明显影响。
In order to develop a bond-type anchorage for the carbon fiber reinforced polymer/plastic（CFRP）strand,the bonding behavior of CFRP strand embedded in ultra-high performance reactive powder concrete（RPC）was investigated by static test.Based on the test results,the efficient anchoring modes of CFRP strands in RPC as well as the equations to calculate the interface average bond strength and the critical anchorage length of CFRP strands under different anchoring systems were proposed.The results show that the anchoring mode of CFRP strand in anchoring section has a significant influence on its anchoring performance.The anchoring efficiency of the strand can be significantly improved by decentralizing the CFRP and using single strand to anchor separately strands within the bonding length;the twisted mode of circumjacent wire in CFRP strand is beneficial for its bonding anchorage with RPC but its tensile strength becomes lower.For the CFRP strands with a tensile strength of 2 470 MPa anchoring in the RPC with a compressive strength of 128.8 MPa,the critical anchorage lengths are 120 mm for thesingle centric wire,114 mm for the single circumjacent wire,106 mm for the decentralized CFRP strand and 231 mm for the whole anchored CFRP strand,respectively.Adding steel fibers by less than 2% of the total volume into the RPC has no obvious influence on the bonding behavior between CFRP strands and RPC.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2016年第6期198-206,共9页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51478177)
