Microstructure Evaluation of Thermal Stabilization Marls Case Study: Marl West Bandar Abbas

Marls are among sedimentary deposits that generally contain 35 to 65 percent of clay minerals and calcium carbonate. The presence of clay minerals in marls has significant effect on reduction of slake durability index of marls. Hence, marls stabilization is important. Furthermore, the presence of carbonate as one of the main components of marls has drastic influence on engineering behavior of soils. Heat, both in transient or constant forms, results in physical, mechanical and microstructural alternation of soils, especially the engineering properties of clay soils. Accordingly, the purpose of this study is to investigate the effect of heat treatment on strengthening parameters of marls, microstructural perspective. Impression of heat treatment on behaviors of marls, using macrostructure tests (Unconfined Compressive Strength, Atterberg Limit, Granularity, Slaking, Water Absorption and Linear Shrinkage) and microstructural tests (pH and X-ray diffraction) have been assessed. For this purpose, the specimens are exposed to heating surfaces (25 to 900 °C). examinations with emphasize on microstructural alternations of marls on specified temperatures and effect of temperature variations on mechanical and strengthening specifications of soil, have been conducted. According to the results, on 700°C marl soils have the best compressive strength of 27.69 Kg/cm2 and durability against moisture.