玄武岩纤维筋粘结式锚索的力学性能与破坏形式研究

Study of Mechanical Properties and Failure Modes of Basalt Fiber Reinforced Polymer Bonded Anchor Cable

基于10组玄武岩纤维筋(BFRP)粘结式锚索的静载拉伸试验,分析了不同环氧树脂胶粘结介质、锚固形式(锚固段中部索体削细缩颈处理与未削细)和索体束数对锚索力学性能与破坏形式的影响。研究结果表明:玄武岩纤维筋粘结式锚索单束BFRP平均极限承载力达143.85 kN,3束组合情况下极限承载力达389.61 kN,组合后筋材发生效率折减。由于筋材的脆性特征,锚索张拉过程中达极限强度后筋材易发生炸裂式破坏。对于BFRP粘结式锚索,影响锚固端锚固效果的主要因素为环氧树脂粘结介质的抗压强度与弹性模量。当单根BFRP筋端头进行削细缩径处理时,锚索的极限承载力降低。

Based on the static load tensile tests of 10 groups of basalt fiber reinforced polymer(BFRP)bonded anchor cables,the effects of different epoxy resin bonding medium,anchoring types(cable body trimming in the middle of the anchoring section or not trimming),and the number of cable roots on the mechanical properties and failure modes of the anchor cables were analyzed.The results show that the average ultimate bearing capacity of a single bundle of BFRP bars is 143.85 kN,and the ultimate bearing capacity of three bundles of BFRP bars is 389.61 kN.The reinforcement efficiency decreases after the combination.Due to the brittleness of the reinforcement,it is easy for the reinforcement to rupture when the ultimate strength of the anchor cable is reached during tensioning.For BFRP bonded anchor cable,the main factors affecting the anchoring effect of the anchor end are the compressive strength and elastic modulus of epoxy resin bonding medium.When the end of a single BFRP is reduced,the ultimate bearing capacity of the anchor cable is reduced.