Download PDFOpen PDF in browserThermal and Chemical Degradation of Portland Cement Concrete in the Military AirbaseEasyChair Preprint 7128 pages•Date: January 3, 2019AbstractThe military airbase especially aprons and the rigid pavement are often exposed to engine oil, hydraulic fluid, Jet oil, extreme heat shocks, and varied lengths of repetitive cyclic heat loading. Oils spillage during maintenance of aircraft on the parking apron or venting of oil from the aircraft after the main engine starting is a common phenomenon and inevitable in the airbase. In light of this, the paper presents the degrading mechanism of ordinary Portland cement (OPC) and Portland limestone cement (PLC) concrete in the parking apron and rigid pavement of military airbase. This study identifies the potentially damaging compounds (hydrocarbons) likely present on the airbase. The chemical reactions between Portland cement and the hydrocarbons and their consequences in the airbase concrete are also presented in the study. The effect of auxiliary power units (APUs) exhaust temperature on the airbase concrete and the combined effect of heat and spilled chemical are explained in the present study. The study reveals that APUs exhaust temperature is sufficient to develop thermal cracks in the concrete, as a result, the permeability of concrete increases that allows more chemical spillage in the concrete. The spilled hydrocarbons react greatly with the cement and produce soft salty brittle materials on the top cementitious layer of OPC and PLC concrete that is known as scale. The APUs exhaust gas heat accelerates the pace of chemical reaction and the degradation process. Keyphrases: Airbase, chemical damage, high temperature, jet exhaust, scaling
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