Anchor Bolt Spacing

Bolt spacing bolt spacing requirements range from every 4 feet to every 8 feet depending on your project s design and circumstances.

Anchor bolt spacing. Horizontal shear ca pacity for a specific spacing of anchor bolts is based on bearing of the anchor bolt against concrete or grout. Table c 5a is based on the capacity of the anchor bolt in a properly designed concrete or ma sonry foundation system. Also a bolt must be placed within 1 foot of the ends of each piece as shown in fig.

10 anchor diameter minimum spacing. Placing anchors closer than 10 anchor diameters apart will allow the two anchors holding values to overlap. 51 mm whichever is greater see figure 2.

Using the international building code ibc as a point of reference the maximum spacing for a building of two stories or less is 6 feet 1829 mm on center between anchor bolts. If this information is not available anchor bolt spacing should not exceed 6 feet on center oc. The minimum embedded depth is 7 inches 178 mm and the minimum diameter required is 1 2 12 7 mm.

In many cases increasing the bolt s diameter allows you to increase the minimum spacing requirement. The embedment length of headed bolts lb is measured parallel to the bolt axis from the surface of the masonry to the bolt head bearing surface. This overlapping will decrease the holding values of both anchors as pictured below.

However embedding an anchor too close to the opposite face of the concrete can lead to spalling damage. The spacing and location of the bolts are shown on the drawings. Fbrg 0 35 fc 0 35 2500psi 875psi.

The length of the anchor bolt is found in the specifications. A rule of thumb is that an anchor should have a minimum of 12x the diameter of anchor spacing to an adjacent anchor or to any concrete edge.