Time-enhanced strength increase of an alluvial clay, typical of the northeastern region of Brazil, mixed with different cement dosages

Abstract

Time-enhanced strength increase of alluvial clay mixed with different cement dosages is provided. After clay collection, water was added to the soft clay samples until the moisture rate reached its liquid limit. Doses 200, 400 and 600 kg m-³ were used for the soil/cement mixture. The cement consisted of the Portland type with blast furnace slag (compressive strength ≥ 32 MPa for 28 days) and water/cement ratio was 0.8. After molding, specimens were immersed in water, and subsequently taken to failure in laboratory tests of uniaxial compression, according to the recommendations of the Brazilian Association of Technical Standards (ABNT, 2003), after 7, 28, 56 and 120 days. Soil samples were collected on the coast of the state of Pernambuco, Brazil. The site is characterized by a surface homogeneous layer composed of soft organic clay-silt to very soft clay, with a gray color and a thickness ranging between 12 and 15m. The groundwater level is found at 1.60m depth. Parameters verified the compressive strength for each mixture under analysis and their time-enhanced resistance increase.