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It Is Also Interesting To Note That The Inherent Fire Stability Of Aggregate ...

It is also interesting to note that the inherent fire stability of aggregate is high and in case of the lightweight aggregate it is at a heat of over 2000 degrees Fahrenheit.
As it is stated in the ACI 216 "Standard Method for Determining fire Resistance of
Concrete and Masonry Construction Assemblies", when slab thickness is determined by fire resistance and not by structural criteria (Goists, waffle slabs e.g.), the superior performance of lightweight concrete, will reduce the thickness of slabs resulting in significantly lower concrete volumes, (John P. Ries and Thomas A. Holm, 2006).
From the above it is clear that the fire resistance properties of the lightweight aggregate directly contributes to the overall structural stability and the reduction in the volume occupied by the concrete in the structural applications. This justifies the versatile nature of the lightweight aggregate thus enabling it to be used in innovative structural applications as argued by John P. Ries and Thomas A. Holm (2006).
2.3.2: Service Life of the Structure The service life of the structure is another critical element that is used as measure of economic use in case of assessing the concrete and the aggregate efficiency against the capital invested as argued by John P. Ries and Thomas A. Holm (2006). Glenn A. Black (2004) further states that the durability of lightweight aggregate is high and the life of the structures constructed using lightweight aggregate prove to have higher life durability. The historical evidence to justify the aforementioned include popular structures like The Port of Cosa - built about 273 B.C. where the builders used lightweight concrete made out of natural volcanic materials, The Pantheon that was finished in 27 B.C that incorporates concrete varying in density from bottom to top of the dome and the most popular Coliseum, built in 75 to 80 A.D. where the foundations were cast as lightweight concrete using crushed volcanic lava as argued by John P. Ries and Thomas A. Holm (2006). From the above arguments it is evident that the durability of the structures designed using the lightweight concrete is extensive in nature.
Looking into the more modern examples to justify the service life of the lightweight aggregate used in concrete for construction include the lightweight concrete ships built by the American Emergency Fleet Corporation during the First World War. The compressive strengths of the concrete used were in the range of 5000 psi (35 MPa) obtaining a unit weight of 110 lb/ftJ (1760 kg/mJ) or less using the rotary kiln produced expanded shale and clay aggregate as identified by John P. Ries and Thomas A. Holm (2006). The service of these lightweight concrete boats during the world wars and their subsequent in the merchant ships justify the durability and service life of the lightweight aggregate used in concrete construction applications.


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