The importance of the construction of concrete grouting material coarse aggregate to choose

grouting grouting material manufacturer grouting material price according to the particle size of aggregate intrusive divided into coarse aggregate and fine aggregate, accounted for about 70% ~ 80% of the volume of concrete, the concrete grouting material in the skeleton effect, can reduce the volume of the concrete grouting material in the condensation sclerosis change. One, the coarse aggregate in concrete grouting material, generally speaking the aggregate particle size greater than 5 mm known as coarse aggregate, commonly used for gravel, coarse aggregate also chooses the pebble in the water conservancy project. 1, the larger particle size selection to reduce the cement dosage and down hydration temperature rise, make concrete grouting material selects larger particle size of rough set grouting material elastic modulus: how much is expected. The larger grain size of coarse aggregate selection of composition, it is necessary to consider structure reinforcement and strength grade and other factors. 2, particle size distribution of the selection of the coarse aggregate in concrete grouting material level is equipped with a succession of grading and size distribution of the two kinds. Succession is graded gravel from small to large grading of each grade are linked together as 5 ~ 40 mm after grading; After grading grading is commonly used in engineering. Make concrete grouting material, aggregate grading and thickness of the two elements should be considered together. If the aggregate gradation is good and particles is larger, the clearing rate and total specific surface area is smaller, the aggregate is more ideal, not only cement dosage is less, but also can improve the compactness of concrete grouting material and strength. 3, impurities and harmful substance content limit impurities ( Mud and clay pieces) And the content of harmful substances have a bad effect on concrete grouting material performance, so in the national standard shall be specified to limit its content, specific reference standard, put forward by the building materials from the durability of concrete grouting material into consideration, should pay special attention to silt content of coarse aggregate and the activity of alkali. For important engineering with gravel, should first adopt method of lithofacies types of inspection activity of alkali aggregate, type and content, if contain active silica, appropriate chooses accelerated mortar bar method inspection; If contain active carbonate, should choose rock column method of inspection. Through examination or alkaline or potential alkali activity, grouting material should be used as concrete aggregate. If it is necessary to use the aggregate, should choose low alkali cement, adding to bay JianJiLiao response technical measures such as admixture, and concrete grouting material prism experiment of alkali activity, examine the measures of aggregate alkali activity effect.