Investigation of soil plug formation in hollow piles using PIV technique

IF 1.7 Q3 ENGINEERING, GEOLOGICAL

Geomechanics and Geoengineering-An International Journal Pub Date : 2021-12-30 DOI:10.1080/17486025.2021.2018509

Sreelakshmi G, Asha M. N

{"title":"Investigation of soil plug formation in hollow piles using PIV technique","authors":"Sreelakshmi G, Asha M. N","doi":"10.1080/17486025.2021.2018509","DOIUrl":null,"url":null,"abstract":"ABSTRACT The foundation systems for bridges and marine structures demand deep foundations like hollow driven open-ended piles, where hard-bearing strata exist on deep soil underneath loose inland and oceanic sea floors. During this driving process, a soil plug is formed near the hollow pile tip region, resulting in soil crushing and compression at the pile tip. The conventional methods fail to predict such volume changes and densification of the embedded soil. The present study utilised Particle Image Velocimetry (PIV) technique to assess the plugging at the pile tip and compare the penetration rate under different infill densities. The PIV results indicated that at a specific energy, pile geometric parameters and infill conditions strongly influenced pile drivability in a granular medium. Due to disturbance caused by pile driving at the base, high compressive strains are observed for large diameter piles, while large dilative strains developed soil plug during the penetration stage for small diameter piles. The plug surface profile was concave for larger diameter piles due to active arching mechanism, while it was convex for small diameter piles due to passive arching generated by lateral soil confinement within the pile wall surface.","PeriodicalId":46470,"journal":{"name":"Geomechanics and Geoengineering-An International Journal","volume":"18 1","pages":"133 - 148"},"PeriodicalIF":1.7000,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geomechanics and Geoengineering-An International Journal","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1080/17486025.2021.2018509","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}

引用次数: 0

Abstract

ABSTRACT The foundation systems for bridges and marine structures demand deep foundations like hollow driven open-ended piles, where hard-bearing strata exist on deep soil underneath loose inland and oceanic sea floors. During this driving process, a soil plug is formed near the hollow pile tip region, resulting in soil crushing and compression at the pile tip. The conventional methods fail to predict such volume changes and densification of the embedded soil. The present study utilised Particle Image Velocimetry (PIV) technique to assess the plugging at the pile tip and compare the penetration rate under different infill densities. The PIV results indicated that at a specific energy, pile geometric parameters and infill conditions strongly influenced pile drivability in a granular medium. Due to disturbance caused by pile driving at the base, high compressive strains are observed for large diameter piles, while large dilative strains developed soil plug during the penetration stage for small diameter piles. The plug surface profile was concave for larger diameter piles due to active arching mechanism, while it was convex for small diameter piles due to passive arching generated by lateral soil confinement within the pile wall surface.

查看原文本刊更多论文

应用PIV技术研究空心桩土塞的形成

摘要：桥梁和海洋结构的基础系统需要像空心开放式桩这样的深基础，在这种情况下，内陆和海洋松散海床下的深层土壤上存在坚硬的持力层。在打桩过程中，在空心桩端区域附近形成土塞，导致桩端土壤被压碎和压缩。传统的方法无法预测这种体积变化和嵌入土壤的致密化。本研究利用粒子图像测速（PIV）技术来评估桩端的堵塞情况，并比较不同填充密度下的渗透率。PIV结果表明，在特定能量下，桩的几何参数和填充条件对颗粒介质中的桩的可驱动性有很大影响。由于基底打桩引起的扰动，大直径桩的压缩应变较高，而小直径桩在贯入阶段产生了较大的膨胀应变。由于主动起拱机制，大直径桩的插塞表面轮廓是凹形的，而小直径桩的堵塞表面轮廓则是凸形的，这是由于桩壁表面内横向土壤约束产生的被动起拱。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Geomechanics and Geoengineering-An International Journal ENGINEERING, GEOLOGICAL-

CiteScore

3.80

自引率

0.00%

发文量

期刊介绍： Geomechanics is concerned with the application of the principle of mechanics to earth-materials (namely geo-material). Geoengineering covers a wide range of engineering disciplines related to geo-materials, such as foundation engineering, slope engineering, tunnelling, rock engineering, engineering geology and geo-environmental engineering. Geomechanics and Geoengineering is a major publication channel for research in the areas of soil and rock mechanics, geotechnical and geological engineering, engineering geology, geo-environmental engineering and all geo-material related engineering and science disciplines. The Journal provides an international forum for the exchange of innovative ideas, especially between researchers in Asia and the rest of the world.