Effects of Chemically Treated Recycled Water on the Setting Process and Overall Behaviour of Concrete Beams

Lilley, Andrew (2018) Effects of Chemically Treated Recycled Water on the Setting Process and Overall Behaviour of Concrete Beams. [USQ Project]


Abstract

With the continuing rise in global population, there is a rising need to find alternate sources of water for human consumption, recreational, agricultural and industrial use. Recycled water usage is becoming increasingly prevalent in regions experiencing water scarcity such as Africa and the Middle East, as well as areas working towards futureproofing from potential water problems such as Australia and the United States. With the increase in population comes an increased demand for housing and critical infrastructure.

This project is aimed at investigating the effects that the use of recycled water has on the behaviour and properties of concrete needed for this infrastructure. The project aimed to achieve this by: 1. Conducting chemical tests to determine the main differences between chosen potable and recycled water sources. 2. Creating concrete specimens with 0%, 25%, 50% and 100% recycled to potable water. 3. Conducting compressive strength and flexural strength tests on the concrete specimens after periods of 28 and 56 days.

The recycled water chosen was obtained downstream from Wetalla Water Reclamation Facility. Through the chemical testing, it was found that the primary differences between the water sources chosen were an increase in water hardness, alkalinity and pH in the recycled water compared to the potable water.

Through compressive testing, it was seen that in the short-term, the control 0% specimens obtained the highest average compressive strength at 49.4 MPa and the 50% specimen the lowest at 44.3 MPa. In the long-term the 25% specimen increased to the highest strength at 55.2 MPa and the 100% specimen the lowest at 47.5 MPa.

With flexural testing, short-term showed 25% specimen with the highest flexural strength at 8.9 MPa with control the lowest at 7.9 MPa. This again changes with long-term testing, with control having the highest flexural strength at 9.5 MPa, and 100% the lowest, decreasing in strength to 7.2 MPa.

The results of this investigation lead to the indication that in the long-term, small amounts of recycled water are beneficial for the compressive strength of concrete, but do not increase the flexural strength in comparison to potable water usage. In the short-term the opposite occurs, with potable water being most effective for compressive strength while the addition of recycled water helped with flexural strength.

Future work could be conducted into the use of alternate recycled water sources and finding the optimal percentage to increase flexural and compressive properties.


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Item Type: USQ Project
Item Status: Live Archive
Faculty/School / Institute/Centre: Historic - Faculty of Health, Engineering and Sciences - School of Civil Engineering and Surveying (1 Jul 2013 - 31 Dec 2021)
Supervisors: Lokuge, Weena; Banerjee, Sourish
Qualification: Bachelor of Engineering (Honours) (Civil)
Date Deposited: 31 Aug 2022 03:52
Last Modified: 27 Jun 2023 04:34
Uncontrolled Keywords: water; recycled water; concrete
URI: https://sear.unisq.edu.au/id/eprint/40718

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