SR0081813 - Laserfiche WebLink

Home Browse Search

1.3.5.2. SPACING IN STABLE IN-SITU (NATIVE) SOIL CONDITIONS 1.3.5.2.1. The minimum spacing between the sidewall or endcap of the tank and the side of the excavation must be 18 inches [46 cm]. See Figure 1-3. NOTE: All measurements from the tank sidewalls are to be taken from the outside diameter of the tank ribs. 1.3.5.2.2. If two or more tanks are installed in the same hole, allow for at least 18 inches [46 cm] between the tanks. In Canada, the National Fire Code of Canada requires 24 inches [60 cm] between a fuel tank and another tank or structure. See Figure 1-3. MM El EM Figure 1-3 EM MM _ Is MM MM 11 ® .r .� ®® ®® ®® Unstable Soil ®ILII EMMM®®®IM®HMI5 111111®flllfl®�IIII®111111®�Ifll®I� ®®®®®®®®®®®®M ®®®®®®®®®®®®E ®®®®®®®®®®®®m! MM El EM MM MM ®® ®® Unstable Soil ®ILII EMMM®®®IM®HMI5 111111®flllfl®�IIII®111111®�Ifll®I� ®ILII 08 1.3.5.2.3. If two or more tanks are installed in the same hole and deadmen are used, the space between the tanks must be equal to or greater than two times the width of the deadman or deadmen required between the tanks. See Figure 1-2. • The space between tanks using our deadmen is typically 36 inches [91 cm] for 10 -foot -and 12 -foot -diameter tanks, and 24 inches [60 cm] for tanks smaller than 10 feet in diameter. 1.3.5.3. SPACING IN UNSTABLE IN-SITU (NATIVE) SOIL CONDITIONS 1.3.5.3.1. We recommend that the tank owner seek the advice of a local foundation professional engineer if the in-situ soil is soft or inherently unstable (for example, peat, quick -sand, muck, landfill, soft or highly expansive clay, underground stream, etc.), as further described in point 1.3.5.3.2. 1.3.5.3.2. The excavation must allow a minimum space equal to 112 the diameter of the tank between the excavation wall and both the side and the endcap of the tank to enhance lateral resistance (see Figure 1-3), if one of the following criteria is met: • the soil is cohesive soil that is less than 750 lbs./sq. ft. [35.9 kPa] as calculated from an unconfined compression test OR • the soil has an ultimate bearing capacity of less than 3,500 lbs./sq. ft. [167.6 kPa] 1.3.5.3.3. Stabilizing materials, such as a reinforced concrete slab, may be required under the tank as a foundation in addition to the required 12 -inch [30 -cm] bedding in an excavation where the bottom is unstable. 1.3.5.3.4. The spacing between adjacent tanks is to be at least 18 inches [46 cm]. In Canada, the National Fire Code of Canada requires 24 inches [60 cm] between a fuel tank and another tank or structure. See Figure 1-3. 1.3.5.3.5. If deadmen are used, follow the spacing requirements between the tanks given in points 1.3.5.2.2 and 1.3.5.2.3. 1.3.6. ADDING TANKS AT EXISTING LOCATIONS 1.3.6.1. GENERAL 1.3.6.1.1. Additional tanks may be installed at existing locations if proper foundation support exists. 1.3.6.1.2. Backfill support around the existing tanks must not be disturbed. 1.3.6.1.3. It is the responsibility of the tank owner to choose the method of installation. 1.3.6.1.4. We recommend that one of the following methods be used.