Effects of Aging on Freshly Deposited or Densified Calcareous Sands

Abstract

The effect of aging on the strength and compressibility of calcareous desert sands was examined by laboratory and field tests. The field tests included standard penetration and dynamic cone penetration tests on freshly deposited loose calcareous sand at one site in Kuwait City. The laboratory tests included direct shear, consolidation, and California bearing ratio tests on reconstituted compacted specimens from a naturally cemented sand. These tests were conducted at zero time and after aging for different periods in the laboratory. The results indicate an increase in the shear strength and a reduction in compressibility at a decreasing rate with time. The penetration resistance increased by 100 to 200 percent as a result of aging over a period of 1 year. The changes in strength and compressibility are attributed to mechanical effects resulting from particle interlocking, reorientation, and dispersion and increased friction at a constant effective stress.