压花锚在岩土锚固工程中的应用  

Application of Bulb Anchor to Geotechnical Anchorage Engineering

作　　者：赵向阳 

机构地区：[1]重庆高速公路发展有限公司东南分公司,重庆400060

出　　处：《地下空间与工程学报》2008年第5期932-936,958,共6页Chinese Journal of Underground Space and Engineering

摘　　要：普通预应力锚索的常见破坏模式是钢绞线与注浆体脱粘，为防止该类破坏模式的发生并增强内锚固段的承栽强度，将结构工程的压花锚进行改进并应用到岩土锚固工程，设计了8种不同配合比的水泥基注浆体，将普通锚、压花锚锚固在中风化砂岩中，通过抗拔试验获得了岩锚的荷载～位移全过程曲线。结果表明：压花结构在注浆体里产生楔形效应，导致压花锚的荷载传递机理与普通锚明显不同，其承载强度显著高于对应的普通锚，降低了岩锚承载强度对内锚固段长度及注浆体力学性能改变的敏感性。压花锚的上述特性有利于减少锚固工程的用锚数量，节约工程造价，提高安全可靠度，值得推广应用。Debonding of interface between steel strand and grout is the dominant failure mode of conventional prestressed anchor cable, in order to avoid this failure mode, the bulb anchor of structural engineering is modified and used for geotechnical anchorage project to enhance the bearing strength of embedded section. This paper presents eight cement- based grouts with different mixture proportion, the conventional anchors and bulb anchors are grouted in medium - weathered sandstone by these cement - based grouts, the load - displacement curves of these rock cable belts have been obtained from laboratory pull - out tests. The results of tests indicate that load - transfer mechanism of conventional anchor and bulb anchor is obviously different due to wedging effect of bulb structure, the bearing strength of bulb anchor is markedly higher than that of conventional anchor, the bulb structure decreases sensibility of the beating strength of rock cable bolt to embedment length and mechanical performance of cement-based grout. These characteristics of bulb anchor can reduce magnitude of anchor in anchorage engineering, economize the project cost and enhance security and reliability, it is worthy of applying popularly bulb anchor to geotechnical anchorage project.

关 键 词：压花锚 普通锚 岩土锚固 承载强度 

分 类 号：TU753.8[建筑科学—建筑技术科学]