Use Urethane Grout Precautions in Summer
Summer temperatures are high, and easy to wind, the air is dry, so the construction of Urethane Grout will cause a certain impact. Therefore, in order to avoid the impact of these problems on the construction, the use of Urethane Grout in summer must pay attention to the following questions.
First of all, need to pay attention to the pouring, the template, steel, the second secondary Urethane Grout base to sprinkle water, cooling, but also reasonable sub-stratification, so that the old and new pouring interval shorter. If a higher slump of concrete Urethane Grout mixture is required, a superplasticizer should be used and the slump of the mixture produced by some superplasticizer can be maintained for 2 hours.
Second, the need to control the delivery time, transport problems should be shortened to the external transport time, control the transport distance. After the Urethane Grout to the site should be immediately unloaded and poured material, to avoid the residence time is too long cause a greater loss of slump. When the internal conveyor is pumped, the conveyor pipe should cover the damp cloth.
Finally, the aggregate and the mixed water should be avoided by direct sunlight, which can sprinkle the water to cool the aggregate. Mixing water is best to use well water, such as with a storage tank, should avoid direct sunlight. Sprinkle water into the aggregate stack to reduce the temperature of the concrete Urethane Grout aggregate. Avoid the temperature of the Urethane Grout mixture above 30 ° C and, if necessary, add ice to reduce the temperature of the secondary polyurethane grout.
What are the commonly used grouting methods for Urethane Grout? As the Urethane Grout has a strong liquidity, so for plugging, the effect is better. However, today's focus is to introduce a number of grouting methods, we hope that after the use of Urethane Grout to help.
The first is the high funnel method, the high funnel method is the Urethane Grout construction, the Urethane Grout alone can not meet the requirements of the flow, the use of grouting to improve the potential difference to meet the grouting requirements of the method. The method is suitable for large equipment base (side length of more than 3m) grouting. At this point, in the equipment base to arrange the appropriate vent, the hole diameter of not less than 30mm. This grouting method should also be used for equipment with grooves under the box base and base.
Another is the self-weight method, is in the construction of Urethane Grout, the use of its good liquidity characteristics, in the range of free flow within the grouting to meet the grouting requirements of the method used in the lower surface of the equipment base of the second flat grouting equipment.
Finally, there is a method of pressure grouting, pressure grouting method is in the Urethane Grout construction, the use of grouting pressurization equipment to meet the grouting requirements of the method. The method to adapt to the complex structure and anti-hit concrete grouting, this time to use grouting pressurization equipment.
The concrete surface enhancer has a very low surface tension, can quickly penetrate into the concrete, and cement hydration of cement by-products such as calcium hydroxide secondary reaction to generate a large number of silica gel, these gels can be blocked Concrete internal capillary pores, thereby increasing the concrete surface of the compact, compressive strength, hardness.
For small space secondary infusion, can be directly added to the water slurry, the standard type of water for the Urethane Grout 13 to 15%. Aggregate, for the large space concrete hole infusion, you can add 5 ~ 10mm particle size of the stone, the ratio of stone: ugm = 0.3: 1 (special circumstances can be changed according to demand), add water for the Urethane Grout 20%.