The influence of various end restraints and grain shape on the cyclic undrained behaviour of granular materials

ABSTRACT

The paper describes the effect of the various ends restraints on the cyclic liquefaction potential of Karlsruhe fine sand and examines the influence of grain shape and gradation on the cyclic liquefaction susceptibility of granular materials. To assess the influence of grain shape and gradation, three materials with same mean size but two different gradations were considered. Different scenarios were considered including the influence of differing sizes of the porous discs at end platens, influence of sample size ratio at similar diameter and varying membrane thickness. Additionally, the influence of using end lubrication or filter papers is investigated. The results reflect a pronounced effect of the liquefaction resistance of KFS using porous discs with a larger diameter, where a significant increase in the number of cycles to initial liquefaction was noted. Furthermore, initial liquefaction resistance for angular/sub-angular materials reduced with increasing gradation. In contrast, it remained relatively unchanged for round materials.

KEYWORDS:

• Initial liquefaction resistance
• cyclic undrained tests
• end restraints
• grain shape
• cyclic stress ratio

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contributions

Debdeep Sarkar contributed to conceptualization, performing the experiments, data analysis, writing and editing the manuscript, Frederik Koch assisted during the experiments and assisted in proofreading the manuscript, Meisam Goudarzy assisted in conceptualization, data analysis, reviewing and proofreading the manuscript, Torsten Wichtmann contributed in the conceptualization and proofreading the manuscript. All authors have read and approved the manuscript for submission.

Additional information

Funding

This work was supported by the Deutscher Akademischer Austauschdienst [57299294].

Notes on contributors

Debdeep Sarkar

Mr. Debdeep Sarkar is currently a Doctoral student at the Chair of Soil Mechanics, Foundation Engineering and Environmental Geotechnics at the Ruhr-University Bochum. He completed his Bachelors and Masters from the Indian Institute of Engineering Science and Technology, Shibpur and Indian Institute of Technology Bombay in India respectively. His main research focus lies on static, dynamic and cyclic behavior of soils.

Frederik Koch

Mr. Frederik Koch is employed as a scientific assistant at the Chair of Soil Mechanics, Foundation Engineering and Environmental Geotechnics at the Ruhr-University Bochum. He completed his Bachelors and Masters from the same institution. His research focus lies on large scale laboratory testing, centrifuge modeling as well as particle image velocimetry (PIV) techniques.

Meisam Goudarzy

Dr.-Ing. Meisam Goudarzy is a Post doc researcher at the Chair of Soil Mechanics, Foundation Engineering and Environmental Geotechnics at the Ruhr-University Bochum. He has completed his Masters from Amirkabir University of Technology in Iran, and his PhD from Ruhr-University Bochum. His research interests are based in grain shape characterization, static, dynamic and cyclic testing of soils, peat, as well as sand-fine mixtures.

Torsten Wichtmann

Prof. Dr.-Ing. Torsten Wichtmann is the head of the Chair of Soil Mechanics, Foundation Engineering and Environmental Geotechnics at the Ruhr-University Bochum. He has completed his Bachelors, Diploma and PhD from the Ruhr-University Bochum, after which he completed his Habilitation from the Karlsruhe Institute of Technology in Germany. His research interests are but not limited to soil dynamics, experimental soil testing, numerical simulations of geotechnical problems, constitutive modeling of soil behavior, foundations of offshore wind turbines, Thermo-, chemo- and biomechanical interactions in soils as well as mechanized tunneling.