Laboratory and field investigation of cement-stabilized organic soil near flood-prone area

Abstract

Cement stabilization of very high plasticity organic soils (gyttja) near flood-prone areas, is a key to constructing water-retaining structures with optimized foundation works. The company Geo has documented the strength of cement stabilized gyttja samples from the area Jyllinge Nordmark in Denmark, for Keller Funderingsteknik Danmark ApS, who have carried out the stabilization. The strength was determined by Unconfined Compressive Strength (UCS) tests, with support of Consolidated Undrained Triaxial (CU) tests and field vane tests to determine undrained shear strength of the stabilized soil. In the laboratory, specimens were prepared with five different cement contents (60, 80, 100, 125, 150 kg/m3) and the strength determined after curing times of 7, 28 and 91 days. To document the in-situ strength and correlate laboratory and in-situ measurements, two UCS tests and three undrained triaxial tests were carried out on intact specimens taken from the cement stabilized soil. The investigation showed a good correlation between cement content, water content, curing time and compressive strength. Further, comparison with similar tests from Sweden, where cement stabilization is a far more common method, shows good correlation to the Jyllinge Nordmark results.