In-Situ Stabilization of Soil Slopes Using Nailed or Anchored Geosynthetics

Robert M Koerner

doi:10.1007/s40891-014-0002-2

Abstract

The incidence of soil slope instability is, and has been, a natural hazard of major proportions and is ongoing to this day. While stabilization can be afforded by excavation and reconstruction, oftentimes structures and utilities are involved requiring in situ stabilization methods. This paper is focused accordingly. The method uses soil nails or soil anchors connected to a geosynthetic surface covering which is tensioned thereby stabilizing the encapsulated soil and providing tensile reinforcement. The paper is subdivided as follows: (i) introduction and theoretical background, (ii) required theoretical modifications, (iii) basics of soil nailing and anchors along with surface geosynthetics effects, (iv) implementation of the technique, (v) current activities by manufacturers, suppliers and ground modification companies, and (vi) summary and conclusions.

Highlights

Introduction and Theoretical BackgroundOf the various types of ground failure hazards, landslides are at, or near the top, of such lists
Soil Nailing and Surface Geosynthetic Effects. The concept of this in situ stabilization method is shown in Fig. 2 wherein the original focus was on soil nails and the surface geosynthetic
Its focus is on relatively small and localized soil slopes which can be remediated in a low-cost manner

Summary

Introduction and Theoretical Background

Of the various types of ground failure hazards, landslides are at, or near the top, of such lists. There are many geotechnical engineering methods available to analyze such slopes wherein the trajectory of the potential failure plane is of major importance. If it is rotational (circular) a simplified Bishop method (SBM) is commonly used and if it is translational (polygonal) the U.S Army Corps of Engineers (COE) wedge method is commonly used. The COE method consists of utilizing force polygons of active, passive and sometime neutral block wedges, and searching for equilibrium of the soil masses within the potential failure planes. The situation can be configured into the quadratic equation as follows which can be adapted using a spread sheet analysis, Koerner and Soong [7]

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5.10 Watershed

Findings

Summary and Conclusions