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10 Cards in this Set
- Front
- Back
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How and what strengthens a greenhouse? |
Purlins, collarties, gussets and diagonal braces strengthen a greenhouses frame by making it more rigid |
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What can cause stress on greenhouses? |
Snow load, wind load, crop load and the weight of the greenhouse materials. These stresses determine how rigid the greenhouse needs to be. |
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What are the advantages of trusses over rafters? |
-the main advantage is the truss system sells the greenhouse to be up to 60' wide (20m) -the space below the truss system is clear so there is no need for supporting posts -greenhouses constructed with rafters and without support posts can only be up to 25' wide (8m) |
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What do foundations have to support? |
The weight of the structure, crops,snow load, and wind load. Foundations support and anchor the greenhouse gram by resisting up lift and overturning from wind pressure |
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The type and size of the foundation will depend on the |
Demands placed upon it |
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How low should greenhouse foundations go? |
Thy should be below the frost line and a minimum depth of 18'' (.5m) |
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What is the strongest foundation for greenhouse? |
Poured concrete with a 3/8 " diameter steel reinforcing rod is the strongest foundation as it best resists horizontal wind pressure |
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What greenhouse structure is the concrete block foundation best suited for? |
Concrete block is not as strong as poured concrete. Concrete block is best suited for arch type structures |
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What is required to make the concrete block foundation strong? |
The concrete post requires an adequate depth for support. The deeper the post the stronger the structure |
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Gutter connected greenhouses can also be called? |
Ridge and furrow |
