How to construction of grouting material in winter?

Winter grouting material construction requirements: 1, mixing process of warm water should be used, the site should have heating conditions. Stir the water used in the heat treatment, the temperature control in the 30 - 40 degrees Celsius. Indoor construction available iodine tungsten lamp. Ensure the grouting material hydration smoothly, or use the flame to heat up. 2, in order to prevent the grouting material for trapping heat in the process of transportation, the arrangement of grouting material pump, fully considering the transport distance, recently try to decrease the number of the firm for grouting material, pumping pipe insulation with straw bag. When the stage after mixing station also try to reduce the number of the firm. 3, daily average temperature below 5 ℃, shall, according to the standard of winter construction and meet the following requirements ( 1) Measures should be taken to preheat before grouting foundation surface, keep the temperature above 10 ℃, and clear water. （ 2) Before the cold, compressive strength of cement grouting material shall not be less than 5 mpa; （ 3) Outdoor construction with a grass felt, sacks of insulation cover maintenance.