Investigation of soundness and erosion rate of rocks used for strengths the bank river in southern Iraq

Abstract

Rocks are the basic materials that are used to strengthen the banks of rivers. Their properties and characteristics play an important role in controlling erosion problems. This paper compares and studies the soundness and erosion rates of several types of rocks collected from four locations in Muthanna Province, southern Iraq. Soundness testing is performed using two experimental approaches (ASTM C88 method and EN 1367-2 (Annex B) approaches). To perform the erosion test, a rotating erosion testing apparatus (RETA) was built in the laboratory. Soundness tests indicated that the rock of South Muthanna sites (SRM2) had a lower resistance to degradation, whereas the rock of West Muthanna sites (WMA1) had a higher resistance. Both ASTM C88 and EN 1367-2 techniques yield similar results, but the EN 1367-2 method yields greater mass loss than ASTM C88. As well, it was discovered that the porosity of the rock and its capacity to absorb water directly affect the soundness test results. Tests conducted with the erosion function apparatus (EFA) indicated that the erosion rate value is higher than those obtained from the rotating erosion testing apparatus (RETA). High water salinity decreases erosion rates; whereas higher water velocity leads to increase it.