Assesment of the geotechnical properties of stabilized sand-marl mixtures for constructional purposes

Abstract

The use of abundant eastern Saudi sands in construction helps control sand movements which are known to result in many hazards, especially in windy seasons. These sands may not be used as a foundation material in their natural condition. However, when improved, they can be utilized in many applications. Therefore, there is a need to conduct an investigation on sands to help delineate their relevant engineering properties and establish a data base for their eventual classification, as part of regional codes. This is the first primary objective of this study.

Desert and beach dune sands samples were collected from ten (10) different locations in the eastern province of Saudi Arabia. These samples were carefully retrieved from areas having abundant sands that can be used in construction. The samples were characterized and their geotechnical properties were determined. Results reveald that most of these sands are classified as poorly graded and all sands show somewhat similar behavior.

Marls ar considered the best construction material in eastern Saudi arabia. However, the extensive use of marl has depleted local supplies. Such a situation has necessitated the search for alternative material sources. Therefore, blending sand with marl in construction will result in an alternative material, that can be treated or stabilized to improve its engineering properties. This will save the good quality aggregate for future construction projects. In addition, there is a potential need in stabilizing such blends using chemicals such as Portland cement or bitumen '(emulisified and cutback asphalts) that result in a material with acceptable engineering characteristics and are economically advantageous. This constituted the second primary objective of this study.

Results have revealed that most of eastern Saudi sands are classified as poorly graded and all sands show somewhat similar behavior. It also showed that stabilizing sand-marl mixes using Portland cement has brought up a material with the most acceptable engineering characteristics. The mix meets the strength and durability requirements and economically advantageous. On the other hand, stabilizing the mixes using bitumen was rejected.