For a 6-inch sprinkler main supported entirely with post-installed anchors in the vertical position, what is the maximum spacing?

For a 6-inch sprinkler main supported entirely with post-installed anchors in the vertical position, what is the maximum spacing?

• A. 6 feet
• B. 10 feet
• C. 12 feet
• D. 8 feet

Answer: (B)

The key idea is how far apart the supports can be for a heavy vertical sprinkler main that’s attached to concrete with post-installed anchors. Each anchor has a finite capacity to resist pullout and to carry the weight and moment of the pipe. When the pipe runs vertically, the weight of the pipe plus the water inside creates a cantilever load on each support. If the supports are spaced too far apart, a single anchor would have to take too much load, which risks pullout, excessive deflection, or sagging. For a 6-inch sprinkler main in this vertical, post-installed-anchors setup, the distance between supports is limited to about 10 feet. This spacing keeps the load on each anchor within typical allowable capacities and minimizes deflection and movement under service conditions and potential seismic or relief-load forces. Shorter spacings would be more conservative but costlier; longer spacings would exceed what the anchors can safely carry for this pipe size and configuration. In practice, exact numbers can vary with anchor type, embedment depth, concrete strength, and local code or manufacturer guidance, but 10 feet is the standard maximum for this scenario.

The key idea is how far apart the supports can be for a heavy vertical sprinkler main that’s attached to concrete with post-installed anchors. Each anchor has a finite capacity to resist pullout and to carry the weight and moment of the pipe. When the pipe runs vertically, the weight of the pipe plus the water inside creates a cantilever load on each support. If the supports are spaced too far apart, a single anchor would have to take too much load, which risks pullout, excessive deflection, or sagging.

For a 6-inch sprinkler main in this vertical, post-installed-anchors setup, the distance between supports is limited to about 10 feet. This spacing keeps the load on each anchor within typical allowable capacities and minimizes deflection and movement under service conditions and potential seismic or relief-load forces. Shorter spacings would be more conservative but costlier; longer spacings would exceed what the anchors can safely carry for this pipe size and configuration.

In practice, exact numbers can vary with anchor type, embedment depth, concrete strength, and local code or manufacturer guidance, but 10 feet is the standard maximum for this scenario.