Unconfined Compressive Strength of Fly Ash Mixed With Lime Precipitated Waste Sludge and Cement

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)
© 2014 by IJETT Journal
Volume-16 Number-5
Year of Publication : 2014
Authors : Dr. Malik Shoeb Ahmad


Dr. Malik Shoeb Ahmad. "Unconfined Compressive Strength of Fly Ash Mixed With Lime Precipitated Waste Sludge and Cement", International Journal of Engineering Trends and Technology (IJETT), V16(5),216-226 Oct 2014. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group


For an effective disposal of fly ash, avoiding environmental pollution, it is necessary to utilize it on a continuous basis for some beneficial purposes. The present study investigated the feasibility and effectiveness of the fly ash along with lime precipitated waste sludge and cement. The Unconfined Compressive Strength (UCS) tests were carried out on the specimens comprising of fly ash (FA), (5 to 35%) lime precipitated electroplating waste sludge (S) and (2-20%) cement at 7 and 28 days of curing periods. The results of UCS tests indicated that the strength of fly ash increases substantially on addition of lime precipitated sludge and cement. It has been observed that compressive strengths of cement stabilized fly ash were smaller than the cement-sludge stabilized mix. It has also been observed that the strength was increasing upto 20% sludge addition to fly ash-cement mix, however, the strength started decreasing on further addition of sludge beyond 20% to the fly ash-cement combination. The most effective percentage of fly ash-cement-sludge was found as 72%FA+20%S+8%C. The UCS of this mix was found as 18 and 25 MPa at 7 and 28 days of curing respectively. This is substantially higher than the UCS of plain fly ash (1.0 and 2.5 MPa) at the same curing periods respectively. The X-ray analyses of some selected samples using EDX technique were also carried to study the elemental analyses of the various mixes. The EDX data showed that the experimental results obtain by UCS tests were in conformity with the chemical findings of EDX


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Fly ash, Waste Sludge, Cement, UCS, EDX.