Study the vesicular basalt for RCC DongNai 3 Dam

Abstract

 • A cement content of 70 to 90 kg per m 3 of RCC will provide the compressive and tensile strength required by the Dam Design Engineer.

• Up to 5% of ‘dirty basalt' in the rock coming from the quarry can be tolerated in the RCC aggregate. However, strict supervision of the quarry operation by an experienced engineering geologist is a requirement to maintain quality control in the raw feed stockpile.
• The vesicular nature of some of the basalt has little or no impact on the final strength and density or the RCC.
• Ground basalt fines can be used as a substitute for the imported Mua Rua pozzolans.
• Further testing are still to be finalized to confirm tensile strength, E-moduli and thermal stress coefficients.
• The test results from the laboratory test programme and SMEC's resulting recommendation of RCC design mixes to be used for the construction of Dong Nai 3 Dam still need to be verified in a trial embankment construction programme to ensure that the laboratory test results can be consistently achieved under construction conditions in the field using the Contractor's construction equipment and construction methods.

 • Use of the basalt from Quarry C and SMEC's recommended aggregate gradation and cement content should result in a significant reduction in construction costs for Dong Nai 3 Dam.