Large scale tests on geosynthetic reinforced unpaved roads subjected to surface maintenance

Abstract Geosynthetic can be effectively used as reinforcement in paved and unpaved roads. This paper presents a study on the use of geosynthetic to reinforce unpaved roads on poor subgrade. A large equipment was used to perform the tests under cyclic loading and a nonwoven geotextile and a geogrid were used as reinforcing layers installed at the fill-subgrade interface. Displacements along the fill surface and stresses and strains in the subgrade were measured during the tests. Three cyclic loading stages were applied in each test up to a rut depth at the fill surface of 25 mm be reached in each stage. At the end of a loading stage the fill surface was repaired for the following loading stage. Monotonic loading tests were also carried out for comparisons. The results obtained show the significant contribution of the presence of the reinforcement layer in increasing the number of load cycles for a given rut depth to be reached and in reducing the stresses and strains in the subgrade, particularly when geogrid reinforcement was used. It was also observed that monotonic loading tests underestimated the contribution from the reinforcement. A simple cost-effectiveness analysis showed that the reduction of maintenance works due to the use of geosynthetic reinforcement may yield to significant savings in this type of problem, seldom considered in the analysis of the economics of this type of application on a routine basis.

[1]  S W Perkins,et al.  Geosynthetic Reinforcement of Flexible Pavements: Laboratory Based Pavement Test Sections , 1999 .

[2]  Steve L Webster,et al.  Geogrid Reinforced Base Courses for Flexible Pavements for Light Aircraft: Test Section Construction, Behavior Under Traffic, Laboratory Tests, and Design Criteria , 1993 .

[3]  Arthur Casagrande,et al.  Embankment dam engineering;: Casagrande volume , 1973 .

[4]  J. Giroud,et al.  Geotextile-Reinforced Unpaved Road Design , 1981 .

[5]  Xuejun Wen,et al.  Model studies on geogrid- or geocell-reinforced sand cushion on soft soil , 2008 .

[6]  Imad L. Al-Qadi,et al.  LABORATORY EVALUATION OF GEOSYNTHETIC-REINFORCED PAVEMENT SECTIONS , 1994 .

[7]  R. B. Sahu,et al.  Bearing Capacity of a Geotextile-Reinforced Unpaved Road as a Function of Deformation: A Model Study , 1999 .

[8]  G P Raymond,et al.  INVESTIGATION REVEALS THE INTERFACE IS NOT THE BEST PLACE FOR GEOSYNTHETIC REINFORCEMENT , 1995 .

[9]  Raúl J. Marsal,et al.  Large Scale Testing of Rockfill Materials , 1967 .

[10]  Robert M. Koerner,et al.  Designing with Geosynthetics , 1986 .

[11]  Sarah M. Springman,et al.  Full-scale field tests on geosynthetic reinforced unpaved roads on soft subgrade , 2006 .

[12]  R. J. Fannin,et al.  Field Observations on Stabilization of Unpaved Roads with Geosynthetics , 1996 .

[13]  Steve L. Webster.  Geogrid Reinforced Base Course for Flexible Pavements for Light Aircraft: Literature Review and Test Section Design , 1991 .

[14]  Gerald P Raymond,et al.  The effect of geogrid reinforcement on unbound aggregates , 2003 .

[15]  Jie Han,et al.  Investigation of geotextile–soil interaction under a cyclic vertical load using the discrete element method , 2010 .

[16]  R. J. Marsal,et al.  MECHANICAL PROPERTIES OF ROCKFILL , 1973 .

[17]  Ralph Haas,et al.  GEOGRID REINFORCEMENT OF GRANULAR BASES IN FLEXIBLE PAVEMENTS , 1988 .

[18]  S. K. Bhattacharyya,et al.  Construction of unpaved rural road using jute–synthetic blended woven geotextile – A case study , 2009 .

[19]  S W Perkins,et al.  A Synthesis and Evaluation of Geosynthetic-Reinforced Base Layers in Flexible Pavements- Part II , 1997 .

[20]  Cancela Rey,et al.  FIFTH INTERNATIONAL CONFERENCE ON GEOTEXTILES, GEOMEMBRANES AND RELATED PRODUCTS , 1995 .

[21]  Ennio M. Palmeira,et al.  Performance of geosynthetic-reinforced alternative sub-ballast material in a railway track. , 2008 .

[22]  Ennio M. Palmeira,et al.  A STUDY OF THE MECHANICS OF UNPAVED ROADS WITH REFERENCE TO THE EFFECTS OF SURFACE MAINTENANCE , 1993 .

[23]  S. Chandrakaran,et al.  Laboratory performance of unpaved roads reinforced with woven coir geotextiles , 2009 .

[24]  Guy T. Houlsby,et al.  ANALYTICAL AND MODEL STUDIES OF REINFORCEMENT OF A LAYER OF GRANULAR FILL ON A SOFT CLAY SUBGRADE , 1987 .

[25]  S. W. Perkins,et al.  MECHANICAL RESPONSE OF GEOSYNTHETIC-REINFORCED FLEXIBLE PAVEMENTS , 1999 .

[26]  Krystyna Kazimierowicz-Frankowska,et al.  Influence of geosynthetic reinforcement on the load-settlement characteristics of two-layer subgrade , 2007 .