Do you know the three major problems in anchor bolts?

Anchor bolts are used to fix the connection, but some common problems often occur during the application process, such as: the center error of the anchor bolts, the height of the anchor bolts is not suitable, and the common loosening of the anchor bolts. Big problem, how to solve this kind of problem? 1. Dealing with center deviation. When the diameter of the bolt is less than 30mm and the center error is within (10~30)mm, burn the bolt red with an oxyacetylene flame, bend it with a hammer, and then reinforce it with a welded steel plate structure to prevent the bolt from returning to its original position when it is tightened. When the diameter of the bolt exceeds 30mm and the error is relatively large, the bolt can be disconnected and welded in the middle of the bolt with a steel plate. If the bolt's compressive strength is insufficient, two steel plates can be welded on both sides of the bolt for structural reinforcement. The size of the structurally reinforced steel plate should be 3 to 4 times the diameter of the bolt. 2. Treatment of unqualified height of anchor bolts (1) When the height of anchor bolts is too high, the higher part can be cut off and threaded again. (2) When the bolt is slightly lower and the error is less than 15mm, the bolt can be burned red with an oxyacetylene flame, and then it can be lengthened. The way to lengthen is: build a square steel plate with a hole in the middle on two stacks of pads and put it on the anchor bolts, and use non-standard nuts to tighten the torque on the top, and take this opportunity to change the red-hot spot of the bolts. If the bolt is too long and the bolt is too low and the error exceeds 15mm, you can dig a hole around it, cut off the bolt at a distance of about 100mm from the bottom of the ditch, and weld a new non-standard bolt with the same diameter, and use The structure is reinforced by two iron rods. The total length of the iron rod is about 4 to 5 times the diameter of the bolt. 3. The loosening of anchor bolts in the foundation. When the bolts are loose, the bolts should be knocked back to the original point first, and the basic hole should be shoveled into a shape with a large center and small sides, and then two horizontal and vertical round steels should be welded firmly on the bolts, and the pit should be cleaned and grouted with tap water. Wait for condensation before tightening the bolts.