Myth: the basement engineering (basements, underground garage, etc.) with a waterproof coiled material is reliable?

Practice shows that the basement waterproofing materials for construction of the leakage rate is very high, its fundamental reason is: the basement at the grass-roots level surface moisture content is very high, waterproof coiled material waterproof construction requirements of moisture content is not more than 9%, but the basement of the cushion base moisture content is more than 30% commonly, some higher, especially the groove, the moisture content is higher in more than 80-90% with waterproofing construction under the condition of the success rate is almost zero. Shanghai also served as waterproof coiled material is unfavorable for the regulation of underground engineering construction. So we recommended in the water cut of more than 95% of the base construction of inorganic waterproof coating on the surface of, or to use inorganic organic flexible coating waterproof coating and polymer cement base composite construction technology. Special waterproofing materials with special functions are not stated here.

Myth 2:1 m thick, the basement floor waterproof and no need to do?

Concrete water seepage has nothing to do with the thickness, can only play the role of waterproof concrete, but not proof. Concrete is built with mixed cement, sand and gravel, and cement in the cement hydration process, the demand for water is about 25-27%, but only to add 25% of the water can't make concrete mixing into pulp, 40-50% of water must be added to reach the requirement of workability in concrete mixing process. After the cement hydration process, the remaining water evaporated, leaving the space is the water seepage channel -- called capillary netcom.

Myth 3: waterproof coiled material is better than waterproof coating?

Waterproof coiled material thickness is fixed, the construction is simple, the advantage is that it has become the mainstream market products. But there are three waterproof coiled material causes weakness: moisture content > 9% can't construction (the decision) it should not be used for surface moisture content at the grass-roots level high location; Lap prone to fumble, waterproof coiled material 1 m lap once it is difficult to form a whole. And waterproof coating construction after the film is a piece of no big waterproofing materials. Compared to its waterproof effect will be better.

Myth 4: structure from the outside can replace structure waterproof?

Structure since the waterproof is to use additives to achieve the goal of water-proof, it is just a psychological balance. Structure since the waterproof is in concrete mixing with a micro expansive agent (UEA or AEA), its mechanism is 0.2-0.7 expansion stress to compensate shrinkage stress in the hydration process of cement. But it has three strict conditions: 1, the additive must be evenly distributed in the concrete; 2, because of the adding material is lighter, so can't and too thin concrete; Once 3, additive can easily be affected with damp be affected with damp, be affected with damp be affected with damp inflation itself began to complete the task, the harmful additives added and not be affected with damp be affected with damp. It is difficult to achieve in these three conditions in large-scale operations, the reason is simple: 1, the additive is according to the proportion of 8% cement, 8% of the additive added to the number of times the amount of cement in the mixture of sand and gravel, cement homogenization is almost impossible, if you can't homogenization can appear in some places more than additive, in some places less. More than additive can produce excess expansion stress, less place can produce expansion stress. In stress excess or deficiency of the interface will generate stress imbalance, fracture. 2, concrete to ship them out, in order to achieve the result of retarded and the concrete slurry is a relatively thin, such additives can float, float the additive once it's in the upper complete the mission. 3, additive is cheaper, ex-factory price is differ to 1000 yuan a ton, because the material is cheap, so will the packaging is simple, the simple packaging is the Achilles' heel of be affected with damp be affected with damp additive. To sum up the waterproof structure cannot be instead of the outside waterproof.