High-strength non-shrink grout material drying shrinkage cracks of concrete and the prevention and control knowledge

High-strength non-shrink grout high-strength non-shrink grout material price high-strength non-shrink grout material manufacturer high-strength non-shrink grout material structure and many concrete structures in a relatively dry environment work, when non-shrinkage high-strength non-shrink grout material manufacturers low humidity environment, the concrete high-strength non-shrink grout material contains free water will gradually evaporate high-strength non-shrink grout material since the concrete substrate, make the concrete high-strength non-shrink grout material produces drying shrinkage, when the shrinkage stress is greater than the high-strength non-shrink grout material tensile strength of concrete, concrete high-strength non-shrink grout material will appear dry shrinkage cracking phenomenon. One, the influence of concrete high-strength non-shrink grout material drying shrinkage factors include; Gelled material consumption, high-strength non-shrink grout material of concrete water-cement ratio, environment humidity, plus the kind and amount of seam an agent, the air content of concrete high-strength non-shrink grout material, etc. 1, under normal circumstances, the dosage of gelled material, environmental humidity is lower, the more concrete high-strength non-shrink grout material shrinkage is larger; 2, water-binder ratio on concrete high strength non-shrinkage grouting material has a great influence on drying shrinkage, water/cement ratio, the greater the drying shrinkage of concrete high strength non-shrinkage grouting material. Under the conditions allow, should as far as possible on the basis of guarantee the workability reduce high-strength non-shrink grout material of concrete mixing water consumption. 3, plus the seam an agent on the shrinkage of concrete, high strength non-shrinkage grouting material has a certain influence. It is generally believed that mixing and subtract water beautiful seam an agent and super plasticizing beautiful seam an agent with high-strength non-shrink grout material of concrete shrinkage and conditions are not adding plus beauty seam an agent of high strength concrete without grouting material contraction, but adding air-entraining beauty seam an agent of high strength concrete without grouting material has greater contraction. 4, aggregate high-strength non-shrink grout material shrinkage of concrete by the impact. For coarse aggregate, the influence of high-strength non-shrink grout material shrinkage concrete shrinkage factor mainly is the amount of coarse aggregate, particle size and silt, coarse aggregate amount of the high-strength non-shrink grout material inspection according to the number, the greater the particle size, the lower the silt content, its high-strength non-shrink grout material shrinkage of concrete restriction ability stronger, the smaller the shrinkage of concrete, high strength non-shrinkage grouting material. Of fine aggregate fineness modulus is lower, the higher the silt content, reach a certain required cement dosage and the mixing water dosage, the greater the workability of concrete shrinkage of high-strength non-shrinkage grouting material. This is a special fine sand concrete high-strength non-shrink grout material appropriate USES one of the main reasons for low rate of sand. 5, early curing of concrete crack of high-strength non-shrink grout material is crucial. High-strength non-shrinkage grouting material in early concrete hydration degree low, low intensity, water glue is large, are in a low humidity environment of high temperature, the evaporation rate is high, development value and the contraction rate will also increase. Therefore, strengthen early curing high-strength non-shrink grout material to prevent the concrete structure crack, improve the quality of the project is of great significance. Second, different drying shrinkage cracks caused by shrinkage, dry shrinkage duration is longer, usually in the 90 d ( 180 d) After age tends to be stable. Thus, the time of the drying shrinkage cracks are difficult to accurately forecast, most occurred in construction after a certain period of time, or after the project put into use. Dry crack should be dealt with according to specific situation. The calculation when the cracks affect the structure of bearing capacity, dealing with structure reinforcement; When the crack does not affect the safety of the structure and only limited to the structure surface, just on the surface is closed; When cracks will not affect the structural safety and crack length and width are larger, can be repaired with the method of V groove or the grouting process.