What is the mixture for grout used for filling anchor bolt holes?

The recommended mixture for grout used in filling anchor bolt holes typically emphasizes achieving a fluid consistency that allows for easy pouring and ensures complete filling of the voids around the bolts. This is particularly crucial for ensuring good bonding and structural integrity.

Using a mixture of one part cement, two parts sand, and no aggregate, along with water to achieve a fluid consistency, facilitates effective flow into the annular spaces surrounding the anchor bolts. The absence of aggregate in this mixture means that the grout can more easily penetrate into narrow gaps, allowing for better encapsulation of the bolts and reducing the risk of air pockets or voids, which can compromise the anchoring strength.

The other formulations, which include varying proportions of aggregate and aim for a stiffer consistency, may hinder the ability of the grout to flow effectively into the anchor bolt holes, affecting its performance in adhesion and load-bearing capacity. A stiffer grout may not adequately encapsulate the bolts, leading to potential failures under load. Therefore, the fluid consistency of this specific mixture is ideal for achieving the performance required in applications involving anchor bolts.