Experimental investigations to determine the effect of adverse curing conditions on the compressive and tensile strengths of polymer modified concrete (PMC) mixes are reported. Normally, plain concrete should be cured under moist conditions for a minimum period of 7 days after concrete has been placed. However, curing under bad weather conditions, especially in summertime where the ambient temperature may become un-expectantly high (100 F + in the daytime and 90 F + at night) will affect the concrete strength adversely. Plain concrete and polymer modified concrete (PMC) mixes are investigated since the addition of polymer to concrete will provide enhanced permeability and ductility. This research intends to provide guidelines for the preparation and curing of different polymer modified concrete mixes as may be used in pavement (slab on grade), shallow foundation, and bridge piers and to account for adverse hot weather curing conditions which may become un-avoidable. Polymer-cement ratios used were 2.5, and 5 percent of polymer solids. Standard cylinders were tested at which the curing condition was under hot weather condition (ambient temperature) for first 24 hours of the concrete age followed by 27 days of moist curing for plain concrete and dry curing for PMC. Results show a marked reduction in compressive and tensile strengths when wet concrete is exposed to hot weather conditions for first 24 hours, or more of concrete curing age. Properties of (PMC) applicable in geo-technical and structural applications are reported.
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机译：报告了确定不良固化条件对聚合物改性混凝土（PMC）混合物的抗压强度和拉伸强度的影响的实验研究。通常，放置混凝土后，普通混凝土应在潮湿条件下至少固化7天。但是，在恶劣的天气条件下进行固化，尤其是在夏季，此时环境温度可能会变得异常高（白天为100 F +，晚上为90 F +），会对混凝土强度产生不利影响。对普通混凝土和聚合物改性混凝土（PMC）的混合物进行了研究，因为在混凝土中添加聚合物会提高渗透性和延展性。这项研究旨在为可能在路面（台阶上的平板），浅层基础和桥墩中使用的各种聚合物改性混凝土混合物的制备和固化提供指导，并说明不利的高温天气条件，这些条件可能会不可避免。 。所用的聚合物与水泥的比例为2.5，占聚合物固体的5％。测试了标准圆柱体，在混凝土老化的最初24小时内，其固化条件是在炎热天气条件（环境温度）下进行的，随后进行了27天的湿固化（用于普通混凝土）和干固化（用于PMC）。结果表明，当湿混凝土在炎热天气中暴露24小时或更长时间后，其抗压强度和抗拉强度会明显降低。报告了适用于岩土和结构应用的（PMC）的特性。
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