Influence Of Super Absorbent Polymer On The Properties Of Pavement Concrete

The curing method for high performance concrete is a hot issue. In order to achieve a better curing effect, domestic and foreign scholars have put forward the solution of internal curing. Absorbent polymer super, referred to as SAP,which has strong ability to absorb water and water retention capacity that is an excellent internal curing materials. When the relative humidity of concrete is reduced, the SAP particles can released water that absorbed in the concrete mixing process, which improved the relative humidity inside the concrete, and promote the hydration reaction of the cementitious materials. In this paper, the influence by the dosage of SAP, additional amount of water and other factors on the mechanical properties, shrinkage and frost resistance of pavement concrete through of the experiment of mechanical experiment, mortar shrinkage test, concrete shrinkage test, concrete freeze-thaw cycles test were studied. Research results show that:Adding SAP significantly influenced the early strength of concrete but had a lesser influence on later strength of concrete. The greater the amount of SAP content, the greater the loss of concrete strength. When adding SAP in concrete, the appropriate introduction of additional water can reduce the loss of the later strength of concrete. The experimental results show that the optimal SAP content is 0.1% of cement quality, the best additional water diversion is 20 times of the SAP quality for compressive strength of concrete. The loss rate of flexural strength reached minimum which SAP content is 0.1% cement quality, the best additional water diversion is 15 times of the SAP quality.The incorporation of SAP can reduced the shrinkage of cement mortar and concrete. From the test results, the optimal SAP content is 0.3% of cement quality, the best additional water diversion is 20 times of the SAP quality for mortar. The optimal SAP content is 0.2% of cement quality, the best additional water diversion is 30 times of the SAP quality for cement concrete. The shrinkage of C-FA concrete reached minimum which SAP content is 0.3% cement quality, the best additional water diversion is 10 times of the SAP quality.The incorporation of SAP can effectively improve the frost resistance of concrete. From the experimental results, the best SAP content is 0.2 of cement quality. In the case of SAP content determination, the best additional water diversion is 10 times of the SAP quality, in terms of relative dynamic modulus of elasticity and loss rate of compressive strength, the best additional water diversion is 10 times of the SAP quality, in terms of loss rate of flexural strength loss, the best additional water diversion is 20 times of the SAP quality...