Hamad I. AI-AbdulWahhab


Sahel N. Abduljauwad




The Kingdom of Saudi Arabia has nearly completed the construction of major highways and expressways joining main city centers. However, a large number of settlements and agricultural farms are yet to be con­nected to the main highways by the rural or agricultural roads. Locally available soils should be utilized in most effective manner for construction of these roads. Due to high cost of scarce good quality aggregate, the upgrading of marginal abundant material such as marl, sabkha and dune-sand are imperative.

Marl is available in abundance in the Gulf region including the Eastern Province of Saudi Arabia. But its application is limited due to its poor strength. The salt encrusted flat areas known as "sabkha" along the coast and in some nearby depressions of the Arabian Gulf region have been viewed by the engineering commu­nity as potentially troublesome. At most times the sabkha surface is sufficiently strong and durable to serve as a substitute for surface roads. When the crust becomes wet due to rainfall or storm tides, the soluble salts which produce the cementation in the crust dissolve and the sabkha becomes impassible. Dune sand, which is wind-blown sand, is covering the major part of the Eastern Province in Saudi Arabia. This is characterized as poorly graded soil with high perme­ability.

Different stabilization admixtures that may have potential application in improving the engineering performance of the local problematic soils including lime, cement, emulsified asphalt, cutback asphalt and combined stabilizer.