Abstract
This paper presents the results of an investigation using controlled field tests to determine the relation between the static cone resistence (q(c)) and the modulus of subgrade reaction (k) in silty sand soil. CPT and plate load tests were made using two meter cube water tight test pits. The test pits were filled with soil under different degrees of compaction and saturation. The degree of compaction (DC) was between 87.9% and 98.5%, and the degree of saturation (DS) was between 35% and 98%. A linear relation, using statistical regression analysis, was determined between k and q(c). The ratio of k to q(c) was 3.25. prediction of k was inhanced when DC and DS were considered.