高强预压锚固技术抗拔力提升效应  

Uplift Effect of High Strength Preloaded Anchorage

作　　者：刘杰[1,2] 孙涛 杨渝南[1,2] 叶志强 李洪亚 LIU Jie;SUN Tao;YANG Yunan;YE Zhiqiang;LI Hongya(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education,Three Gorges University,Yichang 443002,China;College of Civil Engineering&Architecture,Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002 [2]三峡大学土木与建筑学院,湖北宜昌443002

出　　处：《建筑材料学报》2021年第2期323-332,共10页Journal of Building Materials

基　　金：国家自然科学基金资助项目(51439003,51579138);湖北省技术创新重点项目(2017ACA189);湖北省自然科学基金杰出青年人才计划项目(2018CFA065);三峡大学技术人才计划项目(KJ2014H012);三峡大学硕士学位论文培优基金(2019SSPY035);湖北长江三峡滑坡国家野外科学观测研究站开放基金(2018KTL08)。

摘　　要：提出了一种以大掺量膨胀锚固体作为锚固体的新型自膨胀高强预压锚固技术,阐明了其工作原理.研发了能消除CT伪影、获取极大膨胀应力(大于35 MPa)、精确定位扫描的高强预压锚固体系测试装置及方法,并结合分圈层定量CT图像解析技术,建立了以膨胀剂掺量及临空面距离为变量的CT值预测公式.对自膨胀锚固体及锚固体外土体进行了对比试验,以CT值、径向和环向膨胀应力、体应变为主要表征量,分别得到了其CT值随膨胀压力的线性变化规律、膨胀力径向和环向空间演化规律、体应变随圈层变化规律,定量阐明了锚固体外土体从内圈层到外圈层密实度呈线性降低,而大直径锚固体线性增加的力学机理;揭示了高强预压锚固体系中自膨胀作用引发的密实度和正应力的增大对锚固体抗拔力提升的贡献.A new type of self-expansion and high-strength preloading anchorage technology was presented with large amount of expansion anchor solids as anchor solids.Test device and method for high-strength pre-compression anchorage system that can eliminate CT artifacts,obtain maximum expansion stress(>35 MPa),and accurately locate and scan were developed.Combined with the analysis technology of the quantitative CT image of the ring layer,a prediction formula for CT value was established with the content of expansion agent and the distance of overlying surface as variables.To compare expansive soil anchor solid and anchoring in vitro,let CT value,diameter,ring to the expansion stress and strain be the main representation,CT value was get along with the changing regularity of linear expansion,expansion force size,ring to the spatial evolution rule,body strain increases with the increasing layers of change rule.Layers of soil anchor in vitro from internal to external layers of compactness linearly reduced.Mechanism of linear increase of large diameter anchor solid was elucidated.The results reveals the contribution of the increase of density and normal stress induced by auto expansion to the anti-uplift effect of pulling force in the high-strength preloaded anchorage system.

关 键 词：自膨胀高强预压锚固 CT图像解析 径、环向膨胀应力 

分 类 号：TU455[建筑科学—岩土工程]