Grout construction process and precautions technical standards, by the Jingwei Building Materials Co., Ltd, the provincial repair and reinforcement materials research center to provide finishing.

The purpose of the technical standards is to ensure that the construction results are up to standard, in the actual grout construction process there are many human operations, the correctness of these operations or not may lead to the final construction results, so follow the standard operation, and pay attention to avoid some deviation matters can increase the rate of results up to standard, in order to reduce the chance of various problems brought about by quality problems.
1. Foundation treatment

Clean the surface of equipment foundation without debris, floating slurry, dust, oil and release agent and other debris. 24h before grouting, the surface of equipment foundation should be fully moistened. 1h before grouting, water should be sucked dry.

2. Determine the grouting method

According to the actual situation of the equipment base, choose the corresponding grouting method. Since CGM has good fluidity, in general, "self-weight method grouting" can be used, that is, the slurry is directly grouted from the mouth of the template, completely relying on the self-weight of the slurry to level and fill the whole grouting space; if the grouting area is large, the structure is particularly complex or the space is small and far away, "high funnel method grouting" or "pressure method grouting" can be used. Pressure method grouting" for grouting, to ensure that the slurry can fully fill all corners.

3. Mould support

According to the determined grouting method and grouting construction drawing, the template should be positioned at least 50mm above the upper surface of the equipment base, and the template must be set up tightly and firmly to prevent loosening and leakage.

4. Mixing of grout

According to the product certificate recommended water to material ratio to determine the amount of water, mixing water should be used drinking water, water temperature to 5 ~ 40 ℃ is appropriate, can use mechanical or manual mixing. When using mechanical mixing, the mixing time is generally 1 to 2 minutes. When using manual mixing, it is appropriate to add 2/3 of the amount of water to mix for 2 minutes, and then add the remaining amount of water to continue mixing until uniform.

5. Grouting

Grouting construction should meet the following requirements:

1). The grout should be filled from one side until the other side overflows, so as to facilitate the discharge of air between the equipment base and the concrete foundation and make the grout full, and not from all four sides at the same time.

2). After the grouting starts, it must be carried out continuously without interruption, and the grouting time should be shortened as much as possible.

3). During the grouting process, it should not be vibrated, and if necessary, bamboo slats etc. can be used for pulling infusion.

4). The thickness of each grouting layer should not exceed 100mm.

5). Grouting of longer equipment or track foundation should be constructed in sections. The length of each section should be 7m.

6). If water secretion is found on the surface during grouting, a small amount of CGM dry material can be spread to absorb the water.

7) For grouting of equipment foundation with thickness of grout layer greater than 1000mm, 0.5mm stone can be added in the total amount ratio 1:1 when mixing grout, but it should be tested to determine whether its groutability can meet the requirements.

8). After the equipment foundation grouting is finished, the part to be removed should be treated before the final setting of the grout layer.

9). During the grouting construction process until the demoulding, the grout layer should be avoided from vibration and collision to avoid damaging the uncured grout layer.

10) The horizontal distance between the template and the equipment base should be controlled at about 100mm to facilitate grouting construction.

11）If the phenomenon of running grout occurs in grouting, it should be dealt with in time.

12）When the grouting volume of equipment base is large, mechanical mixing should be used to ensure the grouting construction.