Full-scale investigations into installation damage of nonwoven geotextiles

Sardehaei, Ehsan Amjadi; Mehrjardi, Gholamhossein Tavakoli; Dawson, Andrew

Abstract

Due to the importance of soil reinforcement using geotextiles in geotechnical engineering, study and investigation into long-term performance, design life and survivability of geotextiles, especially due to installation damage are necessary and will affect their economy. During installation, spreading and compaction of backfill materials, geotextiles may encounter severe stresses which can be higher than they will experience in-service. This paper aims to investigate the installation damage of geotextiles, in order to obtain a good approach to the estimation of the material's strength reduction factor. A series of full-scale tests were conducted to simulate the installation process. The study includes four deliberately poorly-graded backfill materials, two kinds of subgrades with different CBR values, three nonwoven needle-punched geotextiles of classes 1, 2 and 3 (according to AASHTO M288-08) and two different relative densities for the backfill materials. Also, to determine how well or how poorly the geotextiles tolerated the imposed construction stresses, grab tensile tests and visual inspections were carried out on geotextile specimens (before and after installation). Visual inspections of the geotextiles revealed sedimentation of fine-grained particles in all specimens and local stretching of geotextiles by larger soil particles which exerted some damage. A regression model is proposed to reliably predict the installation damage reduction factor. The results, obtained by grab tensile tests and via the proposed models, indicated that the strength reduction factor due to installation damage was reduced as the median grain size and relative density of the backfill decreases, stress transferred to the geotextiles' level decreases and as the as-received grab tensile strength of geotextile and the subgrades' CBR value increase.

Citation

Sardehaei, E. A., Mehrjardi, G. T., & Dawson, A. (2019). Full-scale investigations into installation damage of nonwoven geotextiles. Geomechanics and Engineering, 17(1), 81-95. https://doi.org/10.12989/gae.2019.17.1.081

• Journal Article Type: Article
• Acceptance Date: Dec 10, 2018
• Online Publication Date: Jan 20, 2019
• Publication Date: Jan 20, 2019
• Deposit Date: Dec 11, 2018
• Publicly Available Date: Jan 21, 2020
• Journal: Geomechanics and Engineering
• Print ISSN: 2005-307X
• Electronic ISSN: 2092-6219
• Peer Reviewed: Peer Reviewed
• Volume: 17
• Issue: 1
• Pages: 81-95
• DOI: https://doi.org/10.12989/gae.2019.17.1.081
• Keywords: geotextiles; installation damage; grab tensile strength; retained tensile strength; strength
• Public URL: https://nottingham-repository.worktribe.com/output/1406039
• Publisher URL: http://www.techno-press.org/content/?page=article&journal=gae&volume=17&num=1&ordernum=8