玻璃纤维增强聚合物锚杆在地下结构抗浮工程中的研究进展

Research Progress on Glass Fiber Reinforced Polymer Anchors in Anti-floating Engineering of Underground Structures

随着地下空间的不断开发利用,地下结构的埋深越来越大,对岩土体进行锚固已成为工程中至关重要的一环。由于全球环境污染造成极端气候频发,许多城市经常出现地下水位暴涨,从而产生较大的浮力,威胁到建筑结构整体的稳定性。抗浮锚杆因具有施工便捷、成本低、工期短、分散应力、抗浮效果好等优势,成为目前广泛推广的抗浮措施。钢筋锚杆即使采取涂覆防锈层或在注浆中掺加防腐剂等防锈措施,在复杂的地下环境中也极易发生锈蚀,无法作为永久性锚固结构使用,严重影响建筑物的使用寿命,因此选用耐久性较好的锚杆是现阶段抗浮工程中的研究热点。玻璃纤维增强聚合物(Glass fiber reinforced polymer,GFRP)抗浮锚杆与传统钢筋抗浮锚杆相比具有更高的抗拉强度、优异的耐腐蚀性能及良好的绝缘性能,与芳纶纤维增强聚合物(AFRP)锚杆、碳纤维增强聚合物(CFRP)、玄武岩纤维增强聚合物(BFRP)锚杆相比价格更低、性价比更高,近年来在地下结构抗浮工程中备受推崇和青睐。虽然GFRP材料用作锚杆的年限较短,且GFRP锚杆用于地下结构抗浮工程中的相关试验研究较少,未有较为完善的锚固系统应力传递机制及有关GFRP材料与混凝土间黏结性能的研究,有关部门未制定适用于GFRP材料的抗浮锚杆技术规程,但其取代钢筋锚杆用于岩土工程中的研究趋势逐年增长。本文简要介绍了GFRP抗浮锚杆的主要组成部分及工作原理,并对GFRP锚杆在地下结构工程中的抗浮设计相关的试验研究以及在试验基础上进行数值模拟分析的研究现状进行介绍,分析讨论GFRP锚杆在抗浮工程应用中存在的不足,并对GFRP锚杆在抗浮工程领域的未来发展提出建议。

With the continuous development and utilization of underground space,the buried depth of underground structures is getting larger and larger,and anchoring rock and soil has become a vital part of the project.Due to the frequent occurrence of extreme climate caused by global environmental pollution,many cities often experience a phenomenon of groundwater level surge,which causes greater buoyancy and threatens the overall stability of the building structure.The anti-floating anchor has become a widely popular anti-floating measure because of its advantages such as convenient construction,low cost,short construction period,distributed stress,and good anti-floating effect.Even if the steel anchor is coated with anti-rust layer or anti-corrosion agent such as preservative in the grouting,it is easy to rust in the complex underground environment and cannot be used as a permanent anchor,which has an important impact on the service life of the building.Nowadays,the use of more durable anchors for anti-floating engineering is a hot spot in the industry.Glass fiber reinforced polymer(GFRP)anti-floating anchor has higher tensile strength,superior corrosion resistance and insulation than traditional steel anchors.GFRP anchor is less expensive and cost-effective than AFRP(aramid fiber reinforced polymer)anchor,CFRP(carbon fiber reinforced polymer)anchor,and BFRP(basalt fiber reinforced polymer)anchor.In recent years,it has been highly praised and favored in underground structure anti-floating engineering.Due to the short length of the GFRP material used as the anchor rod,the GFRP anchor rod is seldom used in the anti-floating engineering of underground structures.There is no complete stress transmission mechanism of the anchoring system and research on the bonding performance between the GFRP material and the concrete.The relevant departments have not formulated a technical specification for anti-floating anchor rods suitable for GFRP.But many projects have attempted to use GFRP anchors for anti-floating in underground structures,the trend of replacing steel anchors for geotechnical engineering is also increasing year by year.This review briefly introduces the main components and working principle of GFRP anti-floating anchor,and introduces the experimental research on the anti-floating design of GFRP anchor in underground structure engineering and the research status of numerical simulation analysis based on the test.In addition,this review analyzes and discusses the shortcomings of GFRP anchors in the research and application of anti-floa-ting engineering,and puts forward suggestions for the future development of GFRP anchors in the field of anti-floating engineering.