济南某石灰岩区高速桥桩底沉渣缺陷处理研究  

Research on Treating the Bottom Sediment of Cast-in-place Piles for an Expressway Bridge in the Limestone Region of Ji′nan

作　　者：姜文富 JIANG Wen-fu(China National Building Materials Group Shandong Building Material&Surveying Institute Co.,Ltd.,Ji′nan 250100,China;Shandong Branch of China National Geological Exploration Center of Building Materials Industry,Ji′nan 250100,China)

机构地区：[1]中建材山东勘测设计研究院有限公司,济南250100 [2]中国建筑材料工业地质勘查中心山东总队,济南250100

出　　处：《价值工程》2024年第16期76-78,共3页Value Engineering

摘　　要：灌注桩的沉渣问题一直是业内关注和研究的重点之一,基本可分为沉渣的成因、沉渣厚度的测量、清孔除渣、后注浆、沉渣缺陷的检测、沉渣缺陷桩的处理这6个研究内容。沉渣缺陷桩的处理,可根据沉渣的严重程度归纳为5种方法。以济南平阴县石灰岩丘陵区某高速桥梁大直径嵌岩灌注桩项目为例,分析了岩溶及其充填物、风化砂岩夹层、泥质条带灰岩层等不良地层条件;选取某棵沉渣缺陷桩,分析了其声波透射法检测结果;重点论述沉渣厚度和分布范围;采用钻杆高压水旋喷、两孔连通交替冲洗清渣;用孔内电视确认清渣效果;最后采用压力注浆,向清渣后形成的空洞内注入P.O 52.5纯水泥浆,成功处理了沉渣缺陷。相关工艺可为相关工程提供参考。The problem with bottom sediment in cast-in-place piles has been one of the key issues that has been the focus of attention and research in the industry for quite some time now.Six research topics are available,including the causes of sediment creation,measuring sediment thickness,cleaning holes for sediment,post-greasing,detecting sediment defects,and treating sediment defect piles.And it is summarized into 5 methods for treating sediment defects depending on the severity of the sediment.The case of the thesis is about the large diameter rock-socketed cast-in-place pile project for an expressway bridge in the limestone region of Jinan Pingyin county.The detrimental effects of poor geological conditions,including Karst and its fillings,weathered sandstone interlayer,and muddy strip limestone layer,have been analyzed.One sediment defect pile with impact-shock hole forming technology has been selected.The detection results of the ultrasonic transmission method have been analyzed.One of the topics of discussion was how to confirm the thickness and distribution range of sediment using the core drilling method with multiple cores.The alternate irrigation technique for cleaning sediment involves using two connected core drillings for high-pressure jet grouting through a drill pipe.Then the effects of cleaning were examined using downhole TV technology.Finally,the pure cement slurry of P.O 52.5 was injected into the cavity formed by the cleaned sediment.After that,the sediment defect pile was successfully treated.Related processes in this thesis may provide some reference to the similar constructions.

关 键 词：沉渣 一桩一探 声波透射法 钻芯法 孔内电视 注浆填充 

分 类 号：TU473.1[建筑科学—结构工程]