Microstructural Investigation of the Engineering Properties of Heated Lime-stabilised Marl soil

Author(s)

Mohammad Amiri Behzad Kalantari Masoud Dehghanih Fatomeh Porhonar Maedeh Papi Rana Salehian Sepideh Taheri

Abstract

Marl soils, with their low bearing capacity, are widely distributed around the world. Stabilising by way of lime or cement additives is common for these soil types to enhance their performance against heat exposure.

Hence, this study investigates the microstructural properties of marl soils that have been stabilised with lime additives under high temperature with special consideration of dihydroxylation temperature. In this regard, marl soils have been first stabilised with 2, 4, 6, 8 and 10 wt% lime and then heated at 100, 200, 300, 500, 700 and 900°C.

Various geotechnical properties have been investigated by unconfined compression strength (UCS) test, Atterberg limits, pH variations and microstructural x-ray diffraction. The results revealed that at temperatures lower than the dihydroxylation temperature, increasing the lime percentage was accompanied by an increase in UCS. However, at higher temperatures, increasing the lime content decreased the UCS.

The addition of 4% lime at ambient temperature increased the UCS to 1.7 MPa, and 3.75 MPa at 500°C.

Keywords

geology geotechnical engineering thermal effects