Evaluating the efficiency of a composite geosynthetic reinforcement in container yard pavements via laboratory plate load test

ABSTRACT

This paper experimentally studies the efficiency of a multi-task geosynthetic comprised of a geogrid and a nonwoven geotextile layer in diminishing the required thickness of base course constructed over different soft subgrades in container yards pavements. In this research, a total number of 24 laboratory static plate load tests (PLT) were conducted in a large-scale steel test box. In all tests, the reinforcement was embedded at the interface of the base course and subgrade to get both reinforcing and separation functions involved simultaneously. The investigated parameter was bearing capacity coefficient K₃₀ obtained directly from the results of laboratory PLTs through a 305 mm-diameter circular steel plate. Results illustrated that in the case of composite-geosynthetic inclusion, the required thickness of the base course could be reduced from 17 to 23 percent depending on the strength of the underlying subgrade layer. This could be both economically and environmentally instrumental in real heavy-duty pavement design. Moreover, considering the geosynthetic end-fixation led to better functionalities of all reinforcements in fixed-end models compared to free-end ones. The results also demonstrated that the efficiency of the geocomposite is contingent on the thickness of the base course. As the thickness increases, the efficiency of the reinforcement reduces.

KEYWORDS:

• Geogrid
• geotextile
• geocomposite
• plate load test
• bearing capacity coefficient
• container yard pavements

Acknowledgements

The authors sincerely appreciate NAUE GmbH & Co. KG and its agent in Iran, Windavar Co., for providing the reinforcement product (Combigrid) with the testing programme. They also wish to thank Dr. S.A. Naeini, head of geotechnical engineering laboratory of Imam Khomeini International University (IKIU) for his valuable comments. Soil mechanics laboratory personnel at IKIU are highly acknowledged for their technical assistance during this research.

Disclosure statement

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