Study of Self-Compacting Concrete for Underwater Construction
WONG ZHENG WEI
|關鍵字:||水中自充填混凝土;抗沖蝕劑;特密管;underwater self-compacting concrete;antiwashout;tremie|
Taiwan is in the seismic region and the design ground acceleration was increased substantially after the 921 earthquake. This leads to the increase of steel ratio and thus the congestion of reinforcements. This causes a problem in compacting and some times even impossible to vibrate the concrete. Self-compacting concrete (SCC) is a concrete which can fill into every corner of the form by its own weight without vibration and no segregation. SCC is gaining popularity all around the world. The underwater RC structures still use traditional underwater concrete. This concrete has good anti-washout capability but the workability is not as good as SCC. In order to guarantee the integrity and quality of underwater RC members, a new type of underwater SCC is thus needed for piers, harbors, slurry walls, and deep foundations. This research develops this underwater SCC which will not segregate in water and have excellent workability and is anti-washout in water. Various agents were tested to determine the suitability. The indices for the performance include pH values, suspended material, anti-washout ability, and workability. It is found that several agents can satisfy the criteria and this new type of concrete is thus developed. The mechanical properties, durability, and volume stability are also tested and all satisfy the criteria in code. The quality of underwater construction is guaranteed.
|Appears in Collections:||Thesis|