岩石GFRP抗浮锚杆承载性能室内试验与机理分析
Full-scale test and mechanism analysis on bearing capacity of GFRP anti-floating anchor socketed into rock

基于4根岩石GFRP抗浮锚杆的室内足尺拉拔破坏性试验，探讨了风化岩地基中全长黏结GFRP抗浮锚杆的界面黏结特性和承载性能，揭示了GFRP锚杆的细观破坏机理。结果表明：GFRP抗浮锚杆发生拔出破坏，主要是由螺纹表面劣化所引起的剪胀破坏；直径25 mm、灌浆体强度M30、锚固长度1.3和0.55 m的GFRP抗浮锚杆的极限抗拔承载力分别为255、195 kN，满足工程抗浮要求；GFRP抗浮锚杆杆体与灌浆体界面平均黏结强度介于2.41~5.10 MPa之间，高于《岩土锚固与喷射混凝土支护工程技术规范》（GB 50086—2015）中钢锚杆与灌浆体的黏结强度推荐值。
Based on the laboratory full-scale tensile failure tests on four full-bonded GFRP anti-anchors socketed into rock, the interfacial adhesion and bearing capacity of the anchor on rock foundation were studied, from which the micro-failure mechanism of the anchor was revealed. The results show that the pull-out failure occurred in GFRP anti-floating anchor, attributing to the dilative shear failure from anchor thread's interfacial deterioration. The ultimate uplift bearing capacity of GFRP anti-floating anchor with diameter of 25 mm, concrete of M30, anchorage length of 1.3 m and 0.55 m, was 255 kN and 195 kN, respectively, indicating that the high bearing capacity of the anchor for anti-floating purpose. The average bond strength between GFRP anti-floating anchor and grouting body was between 2.41 MPa and 5.10 MPa, higher than the recommended values from Technical Code for Engineering of Ground Anchoring and Shotcrete Support"(GB 50086-2015).