24-07-2017, 02:12 PM
29-07-2017, 10:51 AM
Concrete is the main and most widely used construction material in the world for various types of civil engineering works. During the construction of bridges, dams or any other structure where the part of the foundation of the structure is under water, one has to opt for underwater construction. Underwater concrete has been in use for a long time. Technological progress has been made mainly through the development of improved methods for the placement of concrete and better equipment. Improvements have been made in the design of the mixing ratios, the methods of application and the quality of the additives themselves. The top features include: underwater anti-washout property, self-compaction feature, and self-levelling feature. Anti-wash concrete offers superior performance when the concrete is in the fresh state. By adding an anti-wash mixture to the concrete, its viscosity is increased and its resistance to segregation can be improved under the washing action of the concrete. When the concrete is placed under the water, it induces the concrete to deteriorate the uniformity. Therefore, it is important that we follow the proper mix design, concrete production and placement and quality control. This article presents a brief summary of the characteristics of underwater anti-sweeping concrete and discusses the Tremie method, which is the most common method used for laying underwater concrete.