| dc.description.abstract | This study aims at investigating the causes for differing concrete color appearance in members of public works, such as viaducts, bridges or highways; and to offer practical solutions to this problem. The uniformity of concrete color appearance must be maintained in order to look aesthetic, given the geometrical shapes of individual members. And this uniformity must be delivered through careful production of concrete from selection of raw materials, mixing, grouting, and the final maturing. In the past four decades, concrete technology has taken a long leap forward, and the height and complexity of structures, made possible by advances in Self-Compacting Concrete, continue to break records. In 1993, there was the 85-floor Tuntex Building in Kaohsiung; and up to 2003, the age of 101 building, rising 508 meters high, has come.
In 2013, Highway 5 linking Wugu and Yangmei is completed. This project is award winning, in particular the Global Road Achievement Award. But in close observation, it is not difficult to discover the shades of color appearance. Pillars, columns, sections all reflect substantial color differences. In spite of the mandatory standard, such as O3010 Portland Cement Concrete and 03315 Self-Compacting Concrete, announced by Public Construction Commission, uniformity of color appearance among concrete members remain an unsusceptible area of concern among government owner, A/E professions, and contractors. Granted that Self-Compacting Concrete has successfully challenged the 10,000psi threshold, the time is ripe to advance concrete into the age of aesthetic beauty.
This work compiles three decades of working experience by the author, and a myriad of expertise in the concrete related business, and submits a systematic approach in controlling the color of concrete. This involves: 1. Stringent standard required by the Owner, 2. Thoroughly execution of quality assurance, 3. Seamless quality control along the concrete supply chain, 4. Methodology of concrete design with respect to color uniformity, and 5. Smart use of fly ash as a color adjusting material. The key contribution of this work is that the findings in this work can be absorbed into relevant concrete standards, and form new generation ones. | en_US |