Analytical evaluation of partially stiffened granular piled raft with the effect of rigidity of bearing stratum

ABSTRACT

Present study aims to improve the utilisation of granular piles (GP) for ground improvement by analysing the partially stiffened end-bearing granular piled raft (EBGPR) resting on the bearing stratum (BS). The study incorporates the use of the mirror image method and an elastic continuum approach to estimate the vertical settlement of the soil at the interface of the EBGPR. The study focuses on finding normalised variables such as settlement ratio, settlement reduction factor, settlement reduction factor for the BS, settlement influence factor (SIF), SIF for any depth, percentage load on the GP and on the base and normalised shear stress along the length of the GP with the effect of relative size of the raft. Based on the study, it was concluded that the SIF tends to decrease with an increase in the stiffening factor for the top portion of the GP. This finding suggests that the stiffening of the upper part of the GP can improve its strength and stiffness, and can potentially enhance the performance of the EBGPR foundation. Overall, the study is a comprehensive analysis of the partially stiffened EBGPR foundation, and provides useful insights into the behaviour and performance of such foundations.

KEYWORDS:

• Partially stiffened EBGPR
• relative stiffness of bearing stratum (RSBS)
• SIF
• relative stiffness of GP (RSG)
• relative length of stiffening (RLS) from top of pile

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1. At larger spacing between two granular piled raft systems, they will approach as a single granular piled raft due to the lesser influence of the adjacent piled raft.

Additional information

Notes on contributors

Ashish Solanki

Mr. Ashish Solanki is a PhD research scholar in Department of Civil Engineering (Geotechnical Engineering), at Rajasthan Technical University, Kota. He obtained his BTech degree in Civil Engineering from Rajasthan Technical University, Kota in 2014. and MTech degree in Geotechnical Engineering from Rajasthan Technical University, Kota in 2018 with Hons. He has research interests in ground improvement technique, numerical and analytical modelling of pile foundation, computational geomechanics, and stabilization techniques. He has co-guided 01 MTech student. He has authored 11 papers (07 papers in referred journals and 04 in conferences). He is currently serving as a Student Member of American Society of Civil Engineers and also was the reviewer of International Foundations Congress and Equipment Expo (IFCEE21) held in Dallas, Texas, published by ASCE.

Raksha Rani Sanadhya

Dr. Raksha Rani Sanadhya is presently working as Lecturer, Civil Engineering Department, Government Polytechnic College, Kota, since 2009. She obtained her Bachelor's degree from Engineering college Kota, under University of Rajasthan in 2005 with Hons. in Civil Engineering and Master of Technology in Structural Engineering from Rajasthan Technical University in 2013 with Hons. She has research interest in geotechnical and structural engineering. She has authored 07 papers (05 papers in referred journals and 02 in conferences).

Jitendra Kumar Sharma

Dr. Jitendra Kumar Sharma is currently working as a Professor and HOD in Department of Civil, Petroleum, and Petrochemical Engineering at Rajasthan Technical University, Kota and serving since 1990. He also served as Director at Rajkiya Engineering College, Mainpuri. He obtained his PhD degree in Geotechnical Engineering from IIT, Kanpur in 2000. He is an active researcher with research interests includes ground improvement technique, numerical and mathematical modelling, ANN, soil-structure interaction, stabilization techniques and deep foundation. He is guiding 11 PhD (6 awarded one submitted) and more than 15 MTech students. He has authored more than 40 papers in journals and 42 in conferences. He is currently serving as life member of Indian Geotechnical Society, Indian Society for Technical Education, and Indian Grade Drawing, Maharashtra and also reviewer of ELSEVIER and SPRINGER Journals. He addressed several lectures and key note address on Recent Advances in Geotechnical Engineering at MITS, Gwalior. He received IGS-Prof. Dinesh Mohan Biannual Prize in 1997 and was selected as a Young Geotechnical Engineer of IGS from India in 2000. Recently his paper “Effect of Nonlinear Non-homogeneity of Floating Granular Pile and Soil on Settlement” (published in the Series A Journal of IEI, Vol. 100, Issue 2) was selected for the subject prize, ‘Sir Arthur Cotton Memorial’, which was presented at the Prize Distribution Ceremony of the 36th Indian Engineering Congress held at Vigyan Bhawan, Maulana Azad Road, New Delhi 110003 on December 26, 2021.