高性能水中自充填混凝土之研究

Abstract

近幾年來藥劑的改善伴隨著混凝土品質提昇，自充填混凝土在各項工程已漸漸被採用。但在水中或穩定液進行的工程如：連續壁、橋墩等，仍採用高黏滯性、低坍度的傳統水中混凝土或高流動性水中混凝土。對於位在地震帶的台灣來說，較高的鋼筋用量導致間隙更密，除了增加施工的困難性，結構物的品質更是難以控制。若能將水中混凝土達到自行充填的性能且在水中不分散，便能大幅改善水中結構物的品質。 本試驗以自充填特性和水中不分散，以及減少凝結時間為實驗目標，嘗試用不同減水劑搭配不同添加劑改善初凝、終凝時間，從中挑選最好的一組，並開發數種水中自充填混凝土配比。除了基本的工作性測試需符合自充填混凝土規範之外，更要達到水中不分散的要求，並在混凝土硬固後，以一系列力學試驗，確保混凝土的品質。使得施工過程達到快速、環保，降低生態破壞，而水中結構物的品質達到安全、耐久、實用。

Self-compacting concrete is widely used with the improved quality of concrete in recent years, while some underwater construction still adopts traditional concrete. However, as for Taiwan, there many earthquake attack, which leads to a higher reinforcement ratio and small gap among steel rebars for seismic design.Therefore, the concrete posses the ability of both self-compacting and anti-washout is the concrete which can meet the stringent requirements of modern construction. This study aims to develop the concrete with the characteristic of the self-compacting capability and suitable for chemical properties to make sure its suitability for field use and reduce setting time. Besides basic self-compacting for property, anti-washout ability to ensure the quality of the concrete is required, so that the underwater structures can be more reliable, safer, more efficient in construction, and durable.