【 2017 grouting material problem resolution 】 Grouting material construction analysis - cause crack formation High strength cement grouting material

grouting CGM high-strength non-shrinkage grouting material CGM high-strength non-shrinkage grouting material in the construction process of grouting materials, due to the negligence in the process of construction, prone to have a crack. One of the most easy to the cause of crack formation: 1, single large dosage of cement hydration heat high foundation grouting material strength grade for C45, grouting material used in the mixture ratio, dosage of cement is 550 kg/m3, however the cement dosage is large, so the cement strength grade 42. 5 - ( 28 d R ordinary Portland cement, the hydration heat is also other varieties of cement hydration heat is high, the two factors can also affect the cracks. 2, into the mold temperature is too high according to actual operation records, when the sand in the open-air stacking yard, its temperature can reach 35 ℃, the cement temperature for 25 - commonly Also in 15-30 ℃, mixing water temperature 20 ℃, so the grouting material into the mold temperature 30 ℃, the temperature inside the virtually increased grouting material, also increases the grouting material inside and outside temperature difference, it is easier to promote the formation of cracks. 3, the temperature difference between inside and outside control the internal temperature of the grouting material bad English, pronunciation, for example, usage and explanation is provided by check online dictionary, all copyright violations. ℃ or so, and outdoor wall foundation under local section size is ( 0. 6 - 0. 8) m×0。 Article 8 m, the grouting material base surface coefficient is bigger, plus have been rain cooling flushing, and most in the outskirts of the construction site, on the outskirts of field empty, heat faster, cause easily keeping henan zhengzhou CGM high-strength near the surface of the grouting material shrinkage grouting material manufacturers selling in larger temperature gradient. Compressive stress is generated in grouting material caused by grouting material exist near the surface of the larger temperature gradient. Internal pressure, grouting material on the surface, The template surface) Produce large tensile stress, when the temperature of the grouting material is very low, grouting material inside and outside temperature difference T = 40 ℃ & gt; The rules and regulations of 25 ℃) Because of raw surface tensile stress, the temperature difference between inside and outside is the note and the top to the development of cracks, and the base profile template maintenance, cooling slightly slower, but the general rule of surface crack width in the interior. Cracks tend to occur after grouting material pouring temperature stage, generally after grouting material pouring began to appear on the third day after 3 d the temperature cracks. In front of the grouting material construction grouting material must be good control of the temperature difference between inside and outside, to estimate, ensure the smooth progress of construction. Grouting material after watering the 3 d, grouting material internal gradually cooling, cooling temperature and internal cause contraction, and internal mixing in the process of grouting material hardening of hydration and evaporation and the gelation of gel effect, easy to promote grouting material hardening contraction, a comprehensive review in 2014 mid-term exam sprint guiding questions in guangdong region test questions in the process of the jiangsu region test question, the restraint of bedrock and rock bolt, naturally occurring within basis such large tensile stress, tensile stress in the this big tensile strength of grouting material, produced naturally from the basement up the development of cracks, therefore, since the temperature of the surface cracks and the base of temperature shrinkage crack crack form of the project.   5, improper measures of maintenance of the grouting material is easier to cause the formation of cracks due to improper maintenance measures. In-situ maintenance measures for grouting material pouring out the first day of the grouting material for each 0. 5 - 1 h wet curing time, if the casting is reduced after the rain, rain water temperature is 20 ℃ or so commonly, if not to make any cover cause grouting grouting material feeding temperature rose to 40 ℃, the formation of grouting material of the base surface heat faster, so it is important cause of the cracks. CGM orbit cement & # 8203; http://www。 godjc。 com/html/jqgj/16. 超文本标记语言