{"title":"Performance of high capacity socketed H-piles with long rock socket","authors":"Arthur K.O. So","doi":"10.1016/j.sandf.2024.101481","DOIUrl":null,"url":null,"abstract":"<div><p>The pile capacity is commonly calculated by the engineers as the lesser of its structural capacity and the ultimate resistance of ground supporting it using a generalized equation irrespective of the shaft type, socket diameter, socket length, rock type and grout strength. This equation may be over-simplified and risky if the pile/grout/rock interaction is not considered. Based on the loading tests of 6 instrumented socketed piles with 4–6 m rock socket by others and 35 non-instrumented socketed H-piles with 5–34 m rock socket by the author, the load-transfer mechanism in long rock socket is found dependent not only on the mobilization of shear resistance in soil and rock layers, but also largely on the steel/grout bond behavior. A side resistance distribution factor α<sub>s</sub> is introduced as a simple and practical index to represent the load-transfer mechanism along the pile shaft and to the socket. It would increase with an increase in loading and pile length in soils, but decrease with an increase in socket length indicating that critical socket length does exist which is likely depending on the grout bond strength. Average bond stress reduces with increased socket length when the critical socket length is exceeded. Residual settlement is largely due to the slip and bond failure at the interface. Creep settlement is largely affected by the properties of grout mix and tends to increase with increased socket length.</p></div>","PeriodicalId":21857,"journal":{"name":"Soils and Foundations","volume":"64 4","pages":"Article 101481"},"PeriodicalIF":3.3000,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0038080624000593/pdfft?md5=eb82393636865269cbeddb56927a5014&pid=1-s2.0-S0038080624000593-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Soils and Foundations","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0038080624000593","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The pile capacity is commonly calculated by the engineers as the lesser of its structural capacity and the ultimate resistance of ground supporting it using a generalized equation irrespective of the shaft type, socket diameter, socket length, rock type and grout strength. This equation may be over-simplified and risky if the pile/grout/rock interaction is not considered. Based on the loading tests of 6 instrumented socketed piles with 4–6 m rock socket by others and 35 non-instrumented socketed H-piles with 5–34 m rock socket by the author, the load-transfer mechanism in long rock socket is found dependent not only on the mobilization of shear resistance in soil and rock layers, but also largely on the steel/grout bond behavior. A side resistance distribution factor αs is introduced as a simple and practical index to represent the load-transfer mechanism along the pile shaft and to the socket. It would increase with an increase in loading and pile length in soils, but decrease with an increase in socket length indicating that critical socket length does exist which is likely depending on the grout bond strength. Average bond stress reduces with increased socket length when the critical socket length is exceeded. Residual settlement is largely due to the slip and bond failure at the interface. Creep settlement is largely affected by the properties of grout mix and tends to increase with increased socket length.
期刊介绍:
Soils and Foundations is one of the leading journals in the field of soil mechanics and geotechnical engineering. It is the official journal of the Japanese Geotechnical Society (JGS)., The journal publishes a variety of original research paper, technical reports, technical notes, as well as the state-of-the-art reports upon invitation by the Editor, in the fields of soil and rock mechanics, geotechnical engineering, and environmental geotechnics. Since the publication of Volume 1, No.1 issue in June 1960, Soils and Foundations will celebrate the 60th anniversary in the year of 2020.
Soils and Foundations welcomes theoretical as well as practical work associated with the aforementioned field(s). Case studies that describe the original and interdisciplinary work applicable to geotechnical engineering are particularly encouraged. Discussions to each of the published articles are also welcomed in order to provide an avenue in which opinions of peers may be fed back or exchanged. In providing latest expertise on a specific topic, one issue out of six per year on average was allocated to include selected papers from the International Symposia which were held in Japan as well as overseas.