In this paper, the electrochemical impedance spectroscopy method is applied to characteristic the hydration procedure in cement materials. And a new equivalent circuit model is developed to express the hydration procedure of cement material. As cement paste is a complicated electrochemical system with multi-phase transmission, the equivalent circuit model is considered with the additional double layer capacitance effect at the interface among the hydration products in cement materials. It can express the electrochemical station in cement material, as the multi-phase mass transmission in the cement-based material during the hydration procedure.

Self-compacting concrete (SCC) refers to one kind of high-performance concrete which can fill formwork and condensed reinforced steel by the weight of concrete mixture without vibration. In this investigation, local raw materials from Shenzhen Jinqiang Concrete Co. Ltd were employed. Self-compacting concrete mixtures with targeted 3-day compressive strengths of 60MPa or 80MPa and required flow properties were evaluated. Moreover, the SCC was successfully applied in Shenzhen Mangrove Garden project.

In this paper, a new kind of superabsorbent polymer (SAP) is designed and prepared. Using sodium persulfate as initiator and N,N’-methylene bisacrylamide as Crosslinker, monomer of acrylic acid can be grafted into the skeleton of natural mineral kaolin with the method of microwave irradiation. The performance of water adsorption for SAP is tested in saturated Ca(OH)2 solution. Also, the internal curing effect of SAP to hydration procedure of cement paste is studied. The result shows that the compressive properties and flexural strength of cement paste specimens in early stage have significant improvement in contrast to those without superabsorbent polymer or excessive or a small amount of superabsorbent polymer, when superabsorbent polymer is accounted for 0.3% to 0.5% of the total cement.