High Performance Concrete Using Viscosity-Modifying Admixture

• Main Author: Chin, Y ong Kong
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi Petronas 2006
• Subjects: TH Building construction
• Online Access: http://utpedia.utp.edu.my/6953/1/2006%20-%20High%20Performance%20concrete%20using%20viscosity-modifying%20admixture.pdf; http://utpedia.utp.edu.my/6953/

The use of viscosity modifYing admixture (VMA) has proved to be very effective in stabilizing the rheological properties and consistency of self-compacting concrete (SCC). SCC was developed in Japan in the late 1980s, and recently, this concrete has gained wide use with a steadily increasing number of applications in many developed countries such as Europe country and United States but not yet being utilized in Malaysia. SCC is known for its excellent deformability, high resistance to segregation and use, without applying vibration, in congested reinforced concrete structures characterized by difficult casting condition. Identification or production of new low-cost VMA is then essential. This paper presents the performance of local VMA supplied by one manufacturer in enhancing the rheological and consistency properties of cement paste. The study of the rheological properties and consistency of concrete to screen the dosage of VMA to be used in SCC is a promising approach. Investigation was carried out on concrete with VMA and HRWR to verify both admixtures' performance on workability, segregation, filing ability with obstacles, compressive strength and porosity. Besides, fresh and hardened concrete properties will be studied and mixes with various dosage ofVMA to investigate the relationship between all properties. The combined use of proper dosages of VMA and high-range water reducer (HRWR) is shown clearly contribute to higher workability and lesser segregation. The type of VMA and SP used in this study is Vismocrete and Adva that are provided by same manufacturer. Different mix proportion of concrete under same condition must be tested in order to obtain the optimum dosage for best result. Besides, the relationship between fresh and hardened concrete properties were determined in this report. IV