58

Notes

1. Dead loads: 30psf. Platform .steel weight. This includes grating or floor plate, structural framing, supports, toe angle or plate, and handrailing. To find weight of steel, multiply area of platforms bv 30psf.

2. Live loads:

• 0]>erating: Approximately 25-30 psf. Live load is small because it is assumed there are not a lot of people or equipment on the platform while vessel is operating. Combine effects with shell stress due to design pressure.

• Maintenance/comtniction: 50-75psf. Live load is large because there could be numerous persons, tools, and equipment on platforms; however, there would be no internal pressure on vessel.

3. Assume each bracket shares one-half of the area between each of the adjoining brackets. Limit bracket spacing to 6 ft-0 in. arc distance and overhangs to 2ft-0in. For stability, bracket spacing should not exceed 60 .

4. Kneebraces should be 45° wherever possible. Always dimension to bolt holes, not to edge oi brackets or top of clips.

5. Bracket spacing is governed by one of the following conditions:

• Shell stress: Based on dead-load and live-load induced stress from platform support brackets. Shell stresses may be reduced bv using a longer clip or reducing the angle between brackets.

• Bolt shear stress: A-307 or A-325 in single or double shear. Bolt shear stresses may be reduced by increasing the size or number of bolts or increasing the distance between bolts.

• Maximum arc distance: Measured at the outside of the platform. Based on the ability of the toe angle to transmit loads to brackets. Affects "stability" of platform.

• Stress/dcflection of floor plate or grating: Allowable live load affects "springiness of platforms." Use Tables 6-3 and 6-4 and assume "allowable live load" of 150-200 psf.

6. Shell stresses should be checked bv an appropriate "local load" procedure.

Renewable Energy 101

Renewable Energy 101

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable. The usage of renewable energy sources is very important when considering the sustainability of the existing energy usage of the world. While there is currently an abundance of non-renewable energy sources, such as nuclear fuels, these energy sources are depleting. In addition to being a non-renewable supply, the non-renewable energy sources release emissions into the air, which has an adverse effect on the environment.

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