扩大头锚杆研究进展综述  

Advance on the Bit Expanded Anchor

作　　者：蔡强[1,2] 李宝幸 宋军[4] CAI Qiang;LI Bao-xing;SONG Jun(Institute of Exploration Technology,CAGS,Chengdu 611734,China;Technical Center for Geological Hazard Prevention and Control,CGS,Chengdu 611734,China;School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China;Institute of Multipurpose Utilization of Mineral Resources,CAGS,Chengdu 610041,China)

机构地区：[1]中国地质科学院探矿工艺研究所,成都611734 [2]中国地质调查局地质灾害防治技术中心,成都611734 [3]中国地质大学(北京)地球科学与资源学院,北京100083 [4]中国地质科学院矿产综合利用研究所,成都610041

出　　处：《科学技术与工程》2022年第25期10819-10828,共10页Science Technology and Engineering

基　　金：国家重点研发计划(2019YFC1509900)。

摘　　要：扩大头锚杆技术作为一种经济有效的支护方式,被广泛应用于工程建设中,其承载性能优良,在工程地质条件较差、对变形控制要求高的实际工程中发挥着重要作用,然而,目前还没有对这一类型锚杆做过全面系统的梳理。从扩大头锚杆类型、适用性、承载特性、破坏模式、参数选取5个方面综述了近年来扩大头锚杆的主要研究成果,得到如下认识:新型扩大头锚杆的类型较多,大部分不依赖扩孔技术,施工便捷,但新型扩大头锚杆的适用范围相对较窄,一般仅适用于软土地层。常规扩大头锚杆的适用性相较于普通锚杆要广泛,在软弱土地层中也能发挥较好的支护效果,但在黄土、膨胀土和冻土等特殊土地层中的适用性还有待研究。极限承载力是扩大头锚杆承载特性方面的核心内容,但已有理论存在经验值过多、经验系数取值范围大、计算公式尚未形成统一认识的缺陷,同时关于扩大头锚杆轴力、剪应力的研究仍属于扩大头锚杆承载特性的研究空白区。对于扩大头锚的破坏模式,已有研究多是对试验现象的阐述说明,缺乏对现象背后力学机理的解释。扩大头锚杆本身具备较多的可研究参数,目前研究主要集中在扩大头长度和直径,缺乏如扩孔段数、锚固角等各参数以及参数之间的组合研究。As an economic and effective support method,expanded head bolt technology is widely used in engineering construction.It has excellent bearing performance and plays an important role in practical projects with poor engineering geological conditions and high requirements for deformation control.However,at present,no comprehensive and systematic summary of expanded head bolt have been made.The main research results of bit expanded anchor in recent years were summarized from five aspects including type,applicability,load-bearing characteristics,failure mode and parameter.The conclusions can be summarized as follows.There are many new types of bit expanded anchor,most of which are independent of reamed hole technology and convenient for construction.However,the application scope of each new type is narrow,generally only applicable to soft soil layer.The applicability of conventional bit expanded anchor is wider than that of ordinary bolt,and it also has good supporting effect in soft soil layer,but its applicability in special soil layer such as loess,expansive soil and permafrost needs further study.The ultimate bearing capacity is the core content in load features of bit expanded anchor.However,There are many problems with existing theories.For example,there is too much experience value,and the range of empirical coefficient is large,in addition,the calculation formula has not been unified.At the same time,there is still little research on axial force and shear stress of bit expanded anchor.As for the failure mode of bit expanded anchor,previous studies have focused on the elaboration of experimental phenomena,and lacked of explanation of the mechanical mechanism behind the phenomenon.The bit expanded anchor itself has many parameters that can be studied.The research mainly focuses on the length and diameter of the expanded head,and lacks the research on parameters such as the number of reaming segments,anchoring angle and the combination of parameters.

关 键 词：扩大头锚杆 锚杆类型 适用性 承载特性 破坏模式 参数研究 

分 类 号：TV223[水利工程—水工结构工程]