? 1. The height difference within 2m of the foundation ground diameter is within 5mm;
? 2. The ground should not be uneven, even if there is a height difference, it needs to be flat and smooth, and there should be no sudden uplift or sudden sinking into the pit;
? 3. The foundation ground needs to be cleaned, and there can be no sundries.
Guangxinlou replied, I hope it will help ~ ~