Water Storage Tank Roof Rafter Beam Earthquake Straps

There are 16 inches of fiberglass insulation above the ceiling.

Water storage tank roof rafter beam earthquake straps.

The roof rafters provide integral structural support to the roof. Fixed conical or dome roof tanks are provided with internal rafters or trusses fig. Plates are arranged with rectangular plates in the centre and sketch plates cut to suit radius around the perimeter. Ceiling is inch plaster with inch plywood backup.

Storage tanks located within the facility shall be constructed in accordance with the most current version of the american water works association awwa standards d100 d 102 and d 104 for construction coating and cathodic protection for at grade welded steel reservoirs. Pressure under pressure testing for the tank s body and roof. Construction of storage tank roof. The top of a tank is constructed from flat plates.

Roof rafters designed using a roof live load greater than 50 lb ft 2 2 400 n m 2 may utilize higher allowable stresses when using material with minimum specified yield strength greater than a36 material. All steel storage tanks shall be 100 welded. In the three dimensional tank most developed models use shell element for the wall the roof and the tank bottom beam elements for the roof rafters and fluid element for liquid containing cylindrical tank. It begins with design.

The event of earthquake the design spectrum for sloshing in tanks the design pressure for silos. Awwa also has standards for coating steel water storage tanks d102 14 and factory coated bolted carbon steel tanks d103 09. Extensive requirements were added for anchor bolts and anchor straps. The storage of water spherical tanks pressure vessels for the storage of high pressure liquefied.

In this work the tank used has been treated by several authors 8 15 the tall tank has a height to a radius ratio h r of 2. Motion in the liquefied gas storage tank caused by the overturning moment induces pulling forces in anchor straps or anchor bolts in place of uplifting the annular plate. Fixed roof of a tank without a pontoon is tested for excessive pressure with the tank filled to the level which is 10 lower the planned level with keeping the load for 30 minutes. Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.

In this case the stretch of the anchor straps or anchor bolts which are provided at the bottom course of the tank should be the subject of careful design. Roof framing consists of pre engineered wood trusses at 16 inches o c. Type of tank roof support structures. The roof is fiberglass shingles with felt on inch plywood.

If you re framing a gable roof on a new house or building a shed or even a doghouse with a gable roof you ll need to cut a number of roof rafters. The top chord consists of 2x6s and the web and bottom chord consist of 2x4s.