Al-Hoceima port reinforced soil slope

Morocco, Al-Hoceima
PET woven geogrids with PVC coating as a structural element for reinforced soil slope construction

Problem:
the Al Hoceima port is undergoing rapid expansion, confirmed by the numerous hotels and administrative buildings. The coastal environment is rocky, with different slopes inclination. An area with lower inclination is found near the port.
From a geotechnical point of view, from top to bottom, this slope consists of highly altered marly schists (area subject to erosion), layers of intermediate fractured limestone and other fractured schists.
The total height of the hillside is about 50 m with an average inclination of 40°.
This area undergoes monitoring and evaluation as it is subject to significant surface erosion phenomena, caused by rainfall, as well as to falling rocks on the roads below.
Above all, the hillside shows deep slides with the sliding surfaces confined in the altered schist layer. Associated with these erosion and slide phenomena are setting-back of the edge of the mountain, risk of damage to or collapse of the buildings on the crest and negative impact on the commercial buildings in the area.

Solution:
to counter the deep slide that involves the hillside under study, pilings were driven into the ground using drilled piles, diameter of 1500 mm, in three orders, evenly spaced.
Upstream and downstream the piling there are two retaining walls, each respectively 7.00 m and 11.50 m high, 63° of inclination.
The Edilgrid® geogrids employed have tensile strengths between 55 and 150 kN/m.
In addition to contributing to the overall stability of the entire hillside by blocking the top slide surfaces (the deep surfaces are intercepted by the pilings), the two reinforced earth enable the positioning of the new local roads. Thereafter, the uphill slope will be reshaped using benching retained by BERLINER walls to fully secure the port area.