Improvement of engineering properties of peat by preconsolidation : a comparison of field and laboratory test results

Abstract

Sri Lanka lies in the monsoon region of South- East Asia. Colombo, the Capital city situated on the Western cost of the island experiences a humid tropical climate with an annual rainfall of 2500 mm. In the Colombo region there exists flood plains of Kelani Gaga to the North and in the in the coastal belt there are some water bodies such as the Kotte Lake, Bolgoda Lake etc. The fluctuation of water table due to excessive rainfall provides suitable condition to accumilate peat deposits in the above areas, as these are poorly drained grounds. The above process has been occuring for a long time and as a result of that now there exists around 2500 acres of marshy land underlain with peat in and around Colombo city. These marshy lands consist of peat layers having thickness around 5m-10m. As most of the lands with good subsoil condition around Colombo are already used up with the development of the country, it is now necessary to use these unused marshy lands for housing and infrastructure development.