BSM Waterproofinging
堡舍密防水In 1855, Joseph Lambert, a Frenchman, designed and built the first cement ship and participated in the World Expo of that year.
During the period of the First World War from 1914 to 1918, due to the serious depletion of steel resources in various European and American countries caused by the war, cement ships were used to replace steel ones, mainly to meet the needs of inland water transportation. During this period, Japan even manufactured four "Momo"-class cement destroyers with a full displacement of 835 tons.
During World War II from 1939 to 1945, as the war intensified, the shortage of steel became increasingly acute in Europe and America. At this time, many large cement ships were built, mainly for practical purposes, to transport military materials and personnel. Among them, the United States built a giant cement freighter of 4,500 tons, fully guaranteeing logistical supply
In 1942, the German chemist Lauritz Jensen developed Capillary/Crystalline Waterproofing Materials (CCCW) to solve the problem of water leakage in cement ships. CCCW gradually found its application in underground military shelters, air defense bunkers, and other waterproof and moisture-proof structures in Germany.
BSM three core technology analysis
BSM adopts the unique catalytic formulation technology, in which the active component will catalyze the production of a large number of water-insoluble dendritic crystals when it meets water inside the concrete, filling the concrete interior and making it more dense.
The active component in BSM can precisely capture the free CA2+ in the concrete to chemical complexation reaction, generating unstable calcium complexes dissolved in water, calcium complexes will diffuse with the water in the structural void, encountering higher activity of hydration potential, the active material will be replaced immediately, calcium turns to form more stable crystals to fill the pores and cracks in the structure. And the active material becomes free radical again with the water penetrating into the concrete interior continue to migrate inside the concrete structure, this process repeatedly cycle, crystals in the generation of more and more in the structural defects, so that the internal reaction gradually form a glued dense impermeable body, thereby enhancing the overall impermeability and waterproofing ability of concrete, re-endowed with the ability. of concrete self-healing.
BSM contains active silicon substances, which can directly participate in the original hydration process of cementitious materials, greatly improving the shape of the hydration products of cementitious materials, from the original large scattered rod-shaped body to a large number of dense needle-like crystals, which can better plug micro-pore channels and micro-cracks. The picture on the left is the ordinary concrete without admixture, it can be seen that the internal hydration products such as calcium isinglass are large scattered rod-like bodies, and the concrete has obvious pores and cracks, while the picture on the right is the dense needle-like shape of the hydration products after admixture, which can effectively fill the gel pores and fine pores inside the concrete after reaction optimization and further enhance the compactness.
A. Amount of admixture: the amount of admixture should be 0.8% to 2.0% of the cement dosage. According to a large number of engineering practice and test analysis: strength grade below C60 concrete, the general BSM301 admixture should be 3.0kg/m3, such as the use of silicate cement or ordinary silicate cement, according to the amount of cement in concrete 300kg/m3 calculation, BSM301 admixture for the amount of cement 1.0% , The amount of BSM301 should be selected according to the importance of the building, the thickness and part of the structure, the role of the environment and construction conditions and other factors. (Note: Because the BSM self-healing impermeable agent in the active catalytic substances mainly react with calcium silicate, silicate hydrate, and then in the concrete micro-pores and capillaries to generate blockage, the role of precipitation material, so the content of calcium silicate in different varieties of cement is very different. (According to our national conditions, the use of different varieties of cement, the amount of BSM301 admixture should be determined by the test; BSM301 admixture of waterproof concrete design, should not set leveling layer and protective layer.)
A. Brush or spray application: (Brush: material/water ratio of 5:2, spray: material/water ratio of 2:1) Add water and mix until sticky paste according to the ratio. Wait for 10 minutes and then stir again until the powder is completely free of particles. According to different substrates and construction site conditions, the ratio of material to water can be adjusted, generally does not affect the effect of waterproofing impermeability. Construction volume of 0.8-1.8Kg/㎡, coating thickness of 1.0 ± 0.2mm. B. Process: to be the first layer of dry solid after the second painting, the second layer of coating direction should be perpendicular to the direction of the first layer. In order to prevent cracks on the surface of the coating, chalking, waterproofing coating should be kept moist, construction is completed with spray water on the coating for spray maintenance, a day need to spray 2-4 times, such as hot and dry days, the number of spraying needs to be increased. Within two days after construction must be protected from rain and frost. Application of long-term submerged environment, waterproof layer should be at least 14 days after curing before water storage.
B. Process: to be the first layer of dry solid after the second painting, the second layer of coating direction should be perpendicular to the direction of the first layer. In order to prevent cracks on the surface of the coating, chalking, waterproofing coating should be kept moist, construction is completed with spray water on the coating for spray maintenance, a day need to spray 2-4 times, such as hot and dry days, the number of spraying needs to be increased. Within two days after construction must be protected from rain and frost. Application of long-term submerged environment, waterproof layer should be at least 14 days after curing before water storage.
(Refer to GB18445-2012 for testing, the above data are from the third-party inspection report)
