STABILIZATION OF CALCAREOUS SEDIMENTS USING CEMENT AND STEEL SLAG AGGREGATE

Saad A. Aiban, Omar S. Baghabra Al-Amoudi, Hamad I. Al-Abdul Wahhab and Habib-R Ahmed

ABSTRACT

Construction of roads and foundations in eastern Saudi Arabia has received special consideration from the concerned authorities due to the lack of good quality materials. Calcareous sediments, locally known as marl, are considered the best candidate for road bases and foundations in the region despite their geotechnical problems such as grain crushing, water sensitivity and inaccurate characterization procedures. The extensive use of these materials without the realization of their abnormal properties has resulted in unsatisfactory performance of many structures. Cracks in walls due to unequal settlement and subsidence of floor slabs have been noticed in few places where marls were used as a foundation or backfill material. In other places, heaving of sidewalks was observed due to the existence of expansive marls. These instances, although considered less frequent compared to those observed in roads, can cause severe damages.

This investigation is one of a series to evaluate the geotechnical properties of over twenty calcareous sediments from different places covering the eastern part of Saudi Arabia. Thereafter, two marl and one caliche soils were selected for detailed characterization and stabilization. The results indicate significant variations in the behavior of these materials whereby their strength exhibited acute water sensitivity. The addition of low cement content or steel slag aggregate improved the strength and reduced the water sensitivity significantly. The effects of cement content, curing procedure, period and temperature; and delay in compaction on the strength and durability of the cement-treated calcareous sediments were investigated. Field trials have indicated an excellent performance of the steel slag aggregate and the cement-treated calcareous sediments.

KEYWORDS

Calcareous sediments, characterization, marl, cement, steel slag, road bases, strength, water sensitivity.