Slope Instability at Nablus-Al Bathan Road, Palestinian Territories (Causes, Analysis and Remedy Measurements)

Nablus-Al Bathan Road which connects Nablus City and Jordan Valley in the West Bank of Palestinian Territories, was widened, reconstructed and rehabilitated in 2009, however, between 2010 and 2012 road defects at several locations were observed. To fix these defects especially at station 2 + 100 of the road, soil replacement in the body of the road and big boulders to support the edge of the road were used. Unfortunately, large settlement occurred in the part of the road under maintenance and more sliding and slope instability occurred in the road at station 2+ 100 during the remedial measures. Studies were carried out to find the causes of this problem. These included surveying of the area, geotechnical studies (making trial pits, performing geophysical seismic exploration and digging out several boreholes), in addition to slope stability analysis. It was found that the main causes of landslides were types of soils at the site, high slopes, groundwater recharged from rainfall and changing of weights (cut and fill). Remedy measures were suggested to overcome sliding problem based on available resources and local technology.