Wash water in the mix: Effects on the compressive strength of concrete

Wasserman, B (2012) Wash water in the mix: Effects on the compressive strength of concrete. International Journal of Construction Education and Research, 8(4), pp. 301-316. ISSN 1557-8771

Abstract

The disposal of concrete wash water has become a significant issue in recent years. The Minnesota Pollution Control Agency currently requires control of all water used to wash concrete ready mix trucks, delivery chutes and tools used to finish concrete. Best Management Practices allow for containment of wash water either on the job site or at the ready mix plant but do not allow for the reuse of the water. ASTM Standards allow for limited reuse of the wash water, but the Minnesota Department of Transportation requires potable water in all concrete mixes used on their jobs. This research was designed to compare the compressive strength of the concrete when made with tap water to the compressive strength of concrete made with wash water. The research was a two by two design with two concrete mixes each paired with tap water and wash water. Fifteen cylinders of each type were mixed and stored for 28 days. They were then tested for compressive strength. When analyzed using a one-way analysis of variance (ANOVA), the cylinders made with wash water tested at a higher mean compressive strength than the cylinders made with tap water. The results were consistent across concrete mix designs.

Item Type: Article
Uncontrolled Keywords: compressive strength; concrete; concrete cylinders; recycle; strength; wash water
Index terms: agency, mix design, pollution, management practice, variance, compressive strength, recycle
Subjects: concrete and cementitious materials, management, waste management, environmental health, sociology, material analysis and testing, measurement and scaling
Topics: Business Strategy, Sustainability, Research Practice, Construction Materials
Descriptive scope: 4 PCTA

N.B. Descriptive scope is a count of how many of the five facets of empirical research are indicated by the words used in title, abstract and keywords. It is not intended as a judgement on the research; merely a count of the kind of word we would expect to indicate Phenomenon, Concepts, Theoretical framing, Empirical techniques, Analytical techniques. If all five are present, then a code of “5 PCTEA” will indicate this. If you feel the coding for this record is questionable, we welcome discussion around the terms we matched or the way we categorized them. The facet you would expect may not be coded, or a facet may be coded inappropriately. This can also bear on a larger question, of which facets should be treated as defining in construction management research. Please get in touch, and we will look at it. More details here