Nowadays, there are more and more ocean engineering. In order to build durable marine engineering, cement concrete with excellent seawater corrosion resistance and freeze-thaw resistance must be used. However, at present, Portland cement or modified Portland cement are used in marine engineering. The seawater corrosion resistance and freeze-thaw resistance of this kind of cement are very poor, which is bound to cause a great increase in the follow-up repair work. In some cases, even affect the engineering life, it is difficult to ensure the design service life.
According to the data provided by China National Building Materials Research Institute in 2018, the K24 of calcium sulphoaluminate cement in the seawater corrosion resistance test is 1.36, which indicates that the strength of the cement sample after immersion in seawater for 24 months is not decreased, but increased by 36%; the marine Portland cement K24 = 0.48, indicating that the strength of the cement sample after 24 months of seawater immersion will decrease by 52%. Obviously, the corrosion resistance of calcium sulphoaluminate cement is much better than that of marine Portland cement.
Since its invention, calcium sulphoaluminate cement has been continuously produced for nearly 40 years. Its products are sold at home and abroad and applied to various projects, including marine engineering. In 1983, the South Gate seawall of Dongshan Island in Fujian Province was constructed with fast setting calcium sulphaluminate cement; in 1984, the Antarctic Great Wall Station and Zhongshan station were constructed with fast hardening calcium sulphoaluminate cement; and in 1996, the Dashawan breakwater of Lianyungang, Jiangsu Province was constructed with fast setting calcium sulphoaluminate cement. In 2018, the Institute of building materials technology and the public service platform of industrial technology foundation of the Ministry of industry and information technology learned that Nanmen seawall and dashawan breakwater are in good condition up to now. According to the local construction personnel, if Portland cement is used, it will have to be repaired after 3-4 years. During a visit to the former director of the Great Wall Station in Antarctica, he learned that the Great Wall Station and Zhongshan station are still in safe use.
