id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
esrj-33849	Sandoval, Eimar; Pando, Miguel A	Experimental assessment of the liquefaction resistance of calcareous biogenous sands	2012	9	.pdf	application/pdf	6445	83	-6	Calcite is the main component of calcareous sand (usually greater than 90% calcium carbonate content) Calcareous sands are unique in terms of particle characteristics, in- cluding mineralogy, shape, surface texture, high void ratio, and intra-po- rosity Calcareous sands have variable cementation, ranging from non-ce- mented to strongly-cemented state These sands are more crushable, more contractive, and less stiff than terrigenous silica sands due to their unique particle properties and carbonate content (Cataño & Pando, 2010) methodology The experimental programme used in this study primarily involved sand mineralogical and grain characterisation, characterising the CSL and consolidated undrained cyclic triaxial testing of specimens prepared using Cabo Rojo calcareous sands and Ottawa silica sands Thirty-nine consoli- dated undrained cyclic triaxial tests were performed: 31 of them on Cabo Rojo calcareous sands and 8 on Ottawa silica sands Description of test sand materials used The calcareous sand being studied was collected from a beach in Puerto Real, Cabo Rojo, south-western Puerto Rico; it was retrieved from the near surface beach using an ordinary shovel and buckets This sand was unce- mented and classified as being white to yellow, fine- to medium-grained, poorly-graded, having sub-angular to angular grains and high internal po- Eimar A Sandoval and Miguel A Pando58 rosity (Figure 2 shows grain characteristics for this sand) For example, Table 1 shows that silica sand is coarser than calcareous sand and its specific gravity is lower Cabo Rojo calcareous grain characteristics Cabo Rojo calcareous sands are sedimentary carbonates for which diagenesis and resulting grain mineralogy are influenced by the depth and temperature of the water column (Morse & Mackenzie 1990, Chaney et al 1982, Morelock & Ramirez 2004) Carbonates are usually dominat- ed by aragonite in shallow waters, followed by magnesium-rich calcites, whereas in deep waters carbonates are composed of calcite having low magnesium content Parameter Cabo rojo calcareous Ottawa silica sand ASTM standard D10 (mm) 0.24 0.65 ASTM D422-463 D30 (mm) 0.30 0.71 D50 (mm) 0.37 0.75 D60 (mm) 0.41 0.78 Cu 1.75 2.1 Cc 0.94 1.1 Gs 2.84 2.65 ASTM D854 min (kN/m3) 9.10 14.6 ASTM D4254emax 2.07 0.78 max (kN/m3) 11.1 17.3 Alternative methodemin 1.51 0.50 Table 1.	cache/esrj-33849.pdf	txt/esrj-33849.txt