Impact of water and soil quality on the degradation of concrete strength in the Vietnamese Mekong Delta, Vietnam

Abstract

The objective of this study is to assess the impacts of physical and chemical parameters of water and soil on the quality of concrete construction works, and thus the degradation of concrete strength due to corrosion in both inland and coastal areas of the Vietnamese Mekong Delta (VMD). Field survey, water and soil samplings were carried out and both in-situ and laboratory testing methods according to the Vietnamese standards were used. Then, the impacts of water and soil characteristics on the concrete strength of construction structures were assessed. The results show that acidic soil (pH < 6.5) as well as metal pollution and soil eutrophication occur in both regions of the VMD. Similarly, HCO3− characterizing alkalinity soil is found to be low in An Giang, Kien Giang, and Soc Trang provinces; and high iron is found in soil in An Giang, Tra Vinh, and Ca Mau provinces. Therefore, natural water used in construction needs to be treated with organic impurities in both regions. In coastal areas, additional treatment of saline water is required to meet Vietnamese standards used for concrete and mortar mixing water (TCVN 4506:2012). It is necessary to pay attention to the acidic nature of soil and water in An Giang province, and the acidic and salty soil properties in Kien Giang province. In addition, the degradation rate of concrete structures is found higher in the coastal area compared to that in the inland area for both concrete working conditions (fully and partially submerged conditions). Therefore, the risk of double impacts from water and soil quality of both “sour” and “salty” properties on the life of concrete structures needs to be further studied.