Geotechnical Characteristics of Stabilized Sabkha Soils from the Egyptian–Libyan Coast

Abstract

Sabkha soils are found in many parts of the world, particularly in arid and semi-arid areas. The sabkha soils have high compressibility and low shear strength. Thus, these soils are not suitable for support of structures and infrastructures without the risk of high settlement and bearing capacity failure. Therefore, the purpose of the present study is to evaluate the geotechnical characteristics of sabkhas sediments from different sites along the Egyptian–Libyan coast. In addition, the study aimed to investigate the geotechnical characteristics of treated sabkha sediments with different dosages (5, 10, 15, 20, and 25 %) of cement kiln dust CKD. Sabkha samples were collected from four different sites along the Egyptian–Libyan coast where they could best represent different sabkha types of these areas. Laboratory tests such as chemical analyses, X-ray diffractometer, index properties, compaction, unconfined compressive strength, and consolidation tests were performed. The results showed that the salt constituent plays an important role in determining the engineering properties of sabkha soil. There is a noticeable strength improvement in sabkha soils with low salinity as compared to those with high salinity. Furthermore, the results showed significant improvement in strength during the first 14 days of curing which was sufficient for the completion of the major reactions between the CKD and the sabkha soils. The addition of 20 % CKD was sufficient to reduce the compression index, CC, by about 17–45 % according to the type of sabkha and salinity concentration.