Abstract
This paper is a review of twenty years of geotechnical investigations conducted at the Na'ur Landslide No. 4, the most historical and important landslide which occurred along the road between Amman-Na'ur and the Dead Sea in Jordan.
The area at Landslide No. 4 is thouroughly studied and many solutions were suggested to pass the road safely through this area. The road was abandoned after successive settlements of the embankment. The adopted solution, however, was to shift the route to the west, cutting through the mountain bordering the studied area. Unfortunately the adopted measures caused many problems and proved to be inadequate in the new road.
This paper presents the hydrology, geomorphology, geology, engineering geology and geotechnical studies of the landslide area. The studies are reviewed in detail to understand the main causes of the movement. Previous geotechnical studies at this site are summarized and discussed and a solution is recommended to stabilize the sliding area in order to let the road pass. This solution is simply to excavate the weak material constituting the embankment of the abandoned road and to reconstruct an embankment founded on solid bedrock. A stability analysis for this solution is presented and a comparison is made between the present as-built road and the recommended solution.
The main conclusions reached in this paper are that the present as-built road will continuously have sliding problems in the future. A reconstruction of the road through the slided area is feasible, the upper slope above the embankment should be flattened; and proper drainage is absolutely necessary.