Installation of shims for static equipment: does the secondary grouting layer bear the load of the equipment?
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In my opinion, shims are used to transfer the load of the equipment to the foundation, while the secondary grouting layer serves only to fix the shims and stabilize lateral forces; it does not bear the weight of the equipment. Is that the case?
The main function of shims is to conveniently provide the equipment with an installation level that meets the requirements, thereby securing it in place； Such rigidity naturally possesses the function of transmitting equipment loads ； Before grouting, each set of shims should be spot-welded in place to prevent loss of levelness due to movement of the shims ；
The main function of shims is to level and align the structure, and together with the secondary grouting layer, they bear the load of the equipment； The secondary grouting layer also bears the load from the equipment.
The secondary grouting layer does not bear the load of the equipment
During the secondary grouting, the anchor bolts have been tightened and the shims have been spot-welded in place; therefore, they will not bear any load from the equipment. Unless the medium inside causes deformation of the equipment’s base frame, in which case the secondary grouting layer will bear some of the load
Under normal circumstances, the load-bearing capacity of a secondary grouting layer is not taken into account. For tower-type equipment, the load-bearing capacity of the shims must be calculated to ensure that both the shims and the concrete foundation on which they rest can support the equipment safely. However, expansion cement must be used for the secondary grouting to ensure tight adhesion to the equipment after the cement has set.
It’s easy to level, and not much force is needed