The Experts below are selected from a list of 12636 Experts worldwide ranked by ideXlab platform
Ibrahim A Shehu - One of the best experts on this subject based on the ideXlab platform.
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evaluation of heat of hydration of concrete containing high volume palm oil fuel ash
Fuel, 2013Co-Authors: A Abdul S M Awal, Ibrahim A ShehuAbstract:Abstract Pozzolanic materials, either naturally occurring or artificially made, have long been in practice since the Early Civilization. In recent years, the utilisation of pozzolanic materials in concrete construction has become increasingly widespread, and this trend is expected to continue in the years ahead because of technological, economical and ecological advantages of the materials. One of the latest additions to the ash family is palm oil fuel ash, a waste material obtained on burning of palm oil husk and palm kernel shell as fuel in palm oil mill boilers, which has been identified as a good pozzolanic material. This paper highlights test results on the performance behaviour of high volume palm oil fuel ash (POFA) in reducing the heat of hydration in concrete. Four concrete mixes namely OPC concrete i.e. concrete with 100% OPC as control, and high volume concrete i.e. concrete with 50%, 60% and 70% POFA were prepared, and the temperature rise due to heat of hydration in all the mixes was recorded. It has been found that palm oil fuel ash significantly reduced the total temperature rise in concrete. The result obtained and the observation made clEarly demonstrate that the high volume replacement of cement by palm oil fuel ash is advantageous, particularly for mass concrete where thermal cracking due to excessive heat rise is of great concern.
A Abdul S M Awal - One of the best experts on this subject based on the ideXlab platform.
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evaluation of heat of hydration of concrete containing high volume palm oil fuel ash
Fuel, 2013Co-Authors: A Abdul S M Awal, Ibrahim A ShehuAbstract:Abstract Pozzolanic materials, either naturally occurring or artificially made, have long been in practice since the Early Civilization. In recent years, the utilisation of pozzolanic materials in concrete construction has become increasingly widespread, and this trend is expected to continue in the years ahead because of technological, economical and ecological advantages of the materials. One of the latest additions to the ash family is palm oil fuel ash, a waste material obtained on burning of palm oil husk and palm kernel shell as fuel in palm oil mill boilers, which has been identified as a good pozzolanic material. This paper highlights test results on the performance behaviour of high volume palm oil fuel ash (POFA) in reducing the heat of hydration in concrete. Four concrete mixes namely OPC concrete i.e. concrete with 100% OPC as control, and high volume concrete i.e. concrete with 50%, 60% and 70% POFA were prepared, and the temperature rise due to heat of hydration in all the mixes was recorded. It has been found that palm oil fuel ash significantly reduced the total temperature rise in concrete. The result obtained and the observation made clEarly demonstrate that the high volume replacement of cement by palm oil fuel ash is advantageous, particularly for mass concrete where thermal cracking due to excessive heat rise is of great concern.
M. Warid Hussin - One of the best experts on this subject based on the ideXlab platform.
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Effect of palm oil fuel ash in controlling heat of hydration of concrete
Procedia Engineering, 2011Co-Authors: A. S.m. Abdul Awal, M. Warid HussinAbstract:Pozzolanic materials, either naturally occurring or artificially made, have long been in practice since the Early Civilization. In recent years, the utilisation of pozzolanic materials in concrete construction has become increasingly widespread, and this trend is expected to continue in the years ahead because of technological, economical and ecological advantages of the materials. One of the latest additions to the ash family is palm oil fuel ash, a waste material obtained on burning of palm oil husk and palm kernel shell as fuel in palm oil mill boilers, which has been identified as a good pozzolanic material. This paper highlights test results on the performance behavior of palm oil fuel ash (POFA) in reducing the heat of hydration of concrete. Two concrete mixes namely OPC concrete i.e. concrete with 100% OPC as control, and POFA concrete i.e. concrete with 30% POFA and 70% OPC were prepared, and the temperature rise due to heat of hydration in both the mixes was recorded. It has been found that palm oil fuel ash not only reduced the total temperature rise but also delayed the time at which the peak temperature occurred. The results obtained and the observation made clEarly demonstrate that the partial replacement of cement by palm oil fuel ash is advantageous, particularly for mass concrete where thermal cracking due to excessive heat rise is of great concern.
A. S.m. Abdul Awal - One of the best experts on this subject based on the ideXlab platform.
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Effect of palm oil fuel ash in controlling heat of hydration of concrete
Procedia Engineering, 2011Co-Authors: A. S.m. Abdul Awal, M. Warid HussinAbstract:Pozzolanic materials, either naturally occurring or artificially made, have long been in practice since the Early Civilization. In recent years, the utilisation of pozzolanic materials in concrete construction has become increasingly widespread, and this trend is expected to continue in the years ahead because of technological, economical and ecological advantages of the materials. One of the latest additions to the ash family is palm oil fuel ash, a waste material obtained on burning of palm oil husk and palm kernel shell as fuel in palm oil mill boilers, which has been identified as a good pozzolanic material. This paper highlights test results on the performance behavior of palm oil fuel ash (POFA) in reducing the heat of hydration of concrete. Two concrete mixes namely OPC concrete i.e. concrete with 100% OPC as control, and POFA concrete i.e. concrete with 30% POFA and 70% OPC were prepared, and the temperature rise due to heat of hydration in both the mixes was recorded. It has been found that palm oil fuel ash not only reduced the total temperature rise but also delayed the time at which the peak temperature occurred. The results obtained and the observation made clEarly demonstrate that the partial replacement of cement by palm oil fuel ash is advantageous, particularly for mass concrete where thermal cracking due to excessive heat rise is of great concern.
Bruce G Trigger - One of the best experts on this subject based on the ideXlab platform.
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understanding Early Civilizations defining Early Civilization
2003Co-Authors: Bruce G TriggerAbstract:Identifying Early Civilizations for comparative study requires ascertaining the general features that distinguish them from both simpler and more complex societies. Such criteria do not constitute an ‘ideal type’, which, according to Max Weber (1949), seeks to order reality by selecting and accentuating certain elements of it. Instead, they identify a natural but not necessarily exclusive category within which it is possible to conduct a more detailed study of differences and similarities. Nevertheless, even postulating such a category as ‘Early Civilizations’ attracts charges of subjectivity and ethnocentric bias. Do Early Civilizations constitute a natural class that is susceptible to the kind of comparative study I am proposing? Does degree of complexity have any real meaning? Is it possible to measure complexity objectively? Do not fundamental historical differences render all societies inappropriate for comparative analysis? Extreme relativists would answer the last question with a resounding yes. ‘Early Civilization’ is undeniably an evolutionary concept. It assumes the existence of less complex societies, some of which evolved into Early Civilizations, and more complex ones, which either developed out of Early Civilizations or grew up alongside of and ultimately replaced them. The aim of my research is not to evaluate the concept of sociocultural evolution (but see Trigger 1998a) or to try to account for how and why Early Civilizations developed. Yet, in order to demonstrate that the societies I am examining are at the same level or stage of development, it is necessary to argue that sociocultural evolution is a valid scientific concept.
