Soil water retention curves of the unsaturated residual soil from the Brazilian coast

This paper presents Soil-Water Retention Curves (SWRC) and pore size distribution data obtained from residuals soils that occurs in natural slopes at north coast of the State of Sao Paulo, Brazil. The experimental results were determined from undisturbed samples collected along two different soil profiles. Three techniques were used to obtain the SWRC: suction plate, pressure plate and filter paper techniques. In addition, some laboratory tests were conducted to provide information about the properties of these materials, such as physical index, grain size distribution and Atterberg limits. The pore size distributions were obtained using mercury intrusion technique. The present paper intend to contribute to a better understanding of the agents and factors for the triggering of the slope failure that frequently occurs in Serra do Mar and to contribute to the data base of SWRC for residual soils.