Calcareous sand is the main material for construction in the islets of the South China Sea.Because of its special biological origin and unique granular structure

its engineering mechanics characteristics are different from those of common terrigenous sand.A series of one-dimensional compression tests with final stress changed from 2 up to 100 MPa were conducted on calcareous sand to study its compression and breakage characteristics.These tests were carried out with triaxial solid-liquid coupling testing machine.The pressure chamber was made of high strength steel in this experiment to avoid test error caused by deformation of steel mold.And parallel uniaxial compression tests were carried out on quartz sand for comparative study with the same test conditions.The results show that the compression deformation of calcareous sand was larger than quartz sand and the yield stress of calcareous sand

which was about 2 MPa

was less than quartz sand.During the test

significant particle breakage was found both in calcareous sand and quartz sand.However

particle crushing of calcareous samples happened earlier than quartz sand.It was found that the degree of particle breakage of the two sand samples increases at first with the increase of load stress

and then tend to be stable

through a quantitative analysis on particle breakage.