A Study On The Resistance Of Chloride Diffusion Into Sulphoaluminate Cement Concrete

The damage for the durability of concrete structures has become a focus of world attention. Whether buildings have been built or concrete projects currently under construction, the durability of concrete are important factors about its design and maintenance in the world. The damage is one of the major disasters that damage national property and threats to the popular safety, and it causes tremendous property damage and casualties. Steel corrosion is the main and most direct factor to the durability of concrete; People are most concerned about it. A large number of studies have shown that the primary cause of steel corrosion is due to chloride corrosion. Chloride is a kind of erosion of the strongest ion,it is widely found in all the surrounding environment of concrete projects, and it role in various ways and various internal penetration into the concrete structure, eventually led to lack of structural durability. In recent decades, for the design and research durability of reinforced concrete structures have been greatly developed at home and abroad in a variety of environmental, especially in chloride environments.Sulphoaluminate cement has the following advantages:early strength, high strength and good impermeability, excellent corrosion resistance and low alkalinity, it is widely used in a variety of special projects, including:winter construction, hydraulic structure engineering and repair the structure works. Currently sulphoaluminate cement has been widely used in concrete structures, especially the structures that require good early strength and durability. However, the study of Sulphoaluminate cement concrete resistance to chloride ion performance is very small, in the chloride environment and without additional additives in it. So we can not ensure its durability in chloride environment. So in this paper, conducted the following research work:(1) The performance of the anti-chloride ion penetration in sulphoaluminate cement mortar. We summed up the mixed-type chloride ion within the Sulphoalumin-ate cement in the propagation and combination of characteristics and analyzed in mixed-type chloride ion on the impact of the early strength of sulphoaluminate cement by comparison and analysis.(2) The performance of the anti-chloride ion penetration of sulphoaluminate cement concrete. We analyzed the performance of the chloride binding and diffusion after it into the concrete and the factors of Sulphoaluminate Cement Concrete in Chloride Properties.(3) The performance of the anti-chloride ion penetration of sulphoaluminate ce-ment concrete after freeze-thaw cycles. We analyzed and compared the performance of before and after freeze-thaw cycles through the ordinary concrete and Sulphoaluminate cement concrete resistance to chloride ion penetration, sum up the performance the two different cement-based concrete resistances to chloride ion penetration after freeze-thaw cycles.(4) Scanning electron microscope of sulphoaluminate cement concrete. We anal-yzed and compared sulphoaluminate cement based concrete and under the same strength grade ordinary portland cement concrete in the internal microstructure, density and other characteristics and, then we Summarized sulphoaluminate cement concrete resistance to chloride ion mechanism from a physical point of view.(5)The X-ray diffraction analysis of sulphoaluminate Cement Concrete. In this paper we analyzed sulphoaluminate cement concrete changes in chemical compositio-n characteristics before and after the chloride ion into the concrete, and than we Summarized sulphoaluminate cement concrete resistance to chloride ion mechanism from a chemical of view.