Deformation-Resistance Model for Geogrid-Reinforced Unpaved Road

Unpaved road sections experience degradation and accumulation of plastic deformation under repeated loading. Geogrid placed between subgrade and aggregate base course (ABC) can improve section performance through several mechanisms and lead to reduction in stresses and plastic deformation. An unpaved road design model that includes provisions for mobilization of subgrade bearing capacity under axisymmetric condition is proposed. The model incorporates base course property, mobilization of subgrade bearing capacity with rutting, degradation of base course stress attenuation with cyclic load, and the effect of reinforcement inclusion. An elastic layer method has been used to back-analyze the vertical stresses on subgrade with data from previous cyclic plate load tests performed in the laboratory. The degradation of unpaved sections was expressed as a reduction in base course-subgrade elastic modulus ratio (E1/E2) with an increasing number of cycles or a decrease in stress distribution angle of base course. ...

[1]  Guy T. Houlsby,et al.  A NEW APPROACH TO THE DESIGN OF UNPAVED ROADS--PART 1 , 1989 .

[2]  J. P. Giroud,et al.  DESIGN OF UNPAVED ROADS AND TRAFFICKED AREAS WITH GEOGRIDS. POLYMER GRID REINFORCEMENT: PROCEEDINGS OF A CONFERENCE SPONSORED BY THE SCIENCE AND ENGINEERING RESEARCH COUNCIL AND NETLON LTD AND HELD IN LONDON 22-23 MARCH 1984 , 1985 .

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

[4]  George Eason,et al.  The plastic indentation of a semi-infinite solid by a perfectly rough circular punch , 1960 .

[5]  Jie Han,et al.  Design Method for Geogrid-Reinforced Unpaved Roads. I. Development of Design Method , 2004 .

[6]  H. G. Hopkins,et al.  Axially symmetric plastic deformations in soils , 1961, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

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

[8]  Mohammed A. Gabr,et al.  Numerical analysis of stress–deformation response in reinforced unpaved road sections , 2005 .

[9]  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 .

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

[11]  Y H Huang.  INFLUENCE CHARTS FOR TWO-LAYER ELASTIC FOUNDATIONS , 1969 .

[12]  E. T. Selig.  Tensile zone effects on performance of layered systems , 1987 .

[13]  Mohammed A. Gabr,et al.  Characteristics of Geogrid-Reinforced Aggregate Under Cyclic Load , 2002 .

[14]  W. Heukelom,et al.  Dynamics Testing of Pavements , 1960 .

[15]  S W Perkins,et al.  Modeling Effects on Reinforcement of Lateral Confinement of Roadway Aggregate , 2005 .