Physical-Mechanical Properties of Rock and Soil in the Coastal Region in Quang Nam and their Influences on the Construction

Abstract

Based on over 3000 data series, of which there are 118 rows of data (test) it is possible to divide the stratigraphy of Quang Nam coastal plain into 5 groups with 42 subgroups of rocks and soils. In which, 17 subgroups of cohesionless soils have the grain composition ranging, the coarser materials show the deeper distribution and therefore having better engineering properties with standard penetration resistance (N30) from 8 to over 50, commonly at N30 = 17 - 32 and standard bearing capacity (Rn) from 0,75 kG/cm2 to more than 60 kG/cm2, commonly at Rn = 1,50 - 3,00 kG/cm2. Cohesive soils are now belonging to the self-compaction process with their natural compaction index of kd = 0,13 - 0,79. The group of soft soils is divided into 7 subgroups, These soils almost extend close to ground surface and so they belong to self-compaction stage (kd = -1,07 -0,31) with high compressibility(a1-2= 0,068 - 0,128cm2/kG), low shear resistance (< 50, C<0,1KG/cm2) and bearing capacity (Rn < 0,5 kG/cm2). These soils have therefore caused adverse effects on the structure stability in the area. The group of hard rocks (3 subgroups) and semi-hard rocks, can be used as natural foundation of different structures and natural construction materials as well.