复杂地层下钻孔灌注桩护壁泥浆对钻孔灌注桩承载性能影响研究分析  

Research and Analysis on the Impact of Wall Protection Grout on the Bearing Capacity of Bored Piles in Complex Formations

作　　者：侯向阳 张旭 孙巍 苗鑫 卞伟 王振军 HOU Xiangyang;ZHANG Xu;SUN Wei;MIAO Xin;BIAN Wei;WANG Zhenjun(China Railway First Group Building&Installation Engineering Co.,Ltd.,Xian Shaanxi 710000,China;Shandong Transportation Institute,Jinan Shandong 250104,China)

机构地区：[1]中铁一局集团建设安装工程有限公司,陕西西安710000 [2]山东省交通科学研究院,山东济南250104

出　　处：《工程质量》2024年第8期77-81,共5页Construction Quality

基　　金：山东省交通运输厅科技计划项目(2023B46)。

摘　　要：本研究重点考察了护壁泥浆对钻孔灌注桩稳定性的影响,并归纳出如下主要结论:①桩体在初始承受荷重时,沉降主要由于桩内部弹性变形产生,随着荷重增大,桩与土之间发生相对位移,此时桩侧摩擦力成为承载的主力;②泥皮的存在能减弱桩体的承载力,泥皮越厚,桩的承载力下降越显著,与无泥皮桩相比,最大承载力分别降低了 14.8 %、16.4 %、26.6 % 和 33.6 %;③泥皮不仅对桩侧的承载力有显著的削弱作用,且随其厚度增加而损失更多,同时也使得施工效率降低;④桩端的阻力会随泥皮的增厚有所提高,在加载初期,桩端阻力在总承载中占据较大份额,但是随着荷重的持续增加,其比重将趋于一个相对稳定的水平。This study specifically focuses on investigating the impact of wall protection mud on the stability of bored piles and presents the following key findings:①Initially,the settlement of the pile is primarily attributed to elastic deformation within the pile.As the load increases,relative displacement occurs between the pile and soil,causing friction on the side of the pile to become the main bearing force.②The presence of a mud skin can diminish the bearing capacity of a pile.The thicker this mud skin becomes,the more pronounced its impact on pile bearing capacity.Compared to piles without a mud skin,there is a reduction in maximum bearing capacity by 14.8%,16.4%,26.6%and 33.6%respectively.③Mud skin not only significantly weakens lateral bearing capacity but also leads to decreased construction efficiency as its thickness increases.④Conversely,as mud skin thickens,it enhances tip resistance in piles.In initial loading stages,tip resistance accounts for a significant portion of total load;however,with continued load increase,its proportion stabilizes at a relatively constant level.

关 键 词：黄河流域 复杂地层 泥浆护壁 钻孔灌注桩 承载性能 

分 类 号：TU753[建筑科学—建筑技术科学]