Values from SJI - 1978
20H7: Nominal Depth = 20 in
Resist Moment = 499,000 in-lbs
Max End Reaction = 5400 lbs
Approx WT = 10.7 lbs
Maxmum Tensile Stress= 30,000 psi
If you have the span, I can give you the allowable loads.
Thanks SlideRuleEra. The information will be appreciated. The gambrel roofs are interesting structures. I'll bet most of them were designed by the seat of someone's pants.
Bracing the top chord of a steel joist with metal deck is one thing but bracing the top chord of a major truss with just metal deck is another thing. The size of the top chord of a major truss would typically not require continuous lateral suport . I think you have to look at the overall...
Would one be able to take composite action from the wood sheathing to increase the moment of inertia? Nailing of the sheathing to the stud would need to be a consideration.
Fibers help to control random shrinkage cracks but you still need to have control joints. Reinforcing in residential construction is kind of a regional thing. Wire mesh is the most typical for residential work. Reinforcing bars are a little overkill for residential. Mesh is admittedly difficult...
A fellow engineer is looking for information on a steel joist called perma-joist(on the drawings). The date of the building is the 1950's and they are used in the roof structure of a school building. I am assuming that this may be just a manufacture's name for a steel joist. Does any one have...
Even vinyl and aluminum siding will develop algae. I have aluminum siding and depending on the humidity, I have to wash off my siding almost every year. Usually this occcurs on the north side of the house. Are your walls properly insulated? It sounds as if exterior moisture is condensing on the...
Are there any forms, report formats or guidelines for reporting on HUD manufactured home foundation inspections? I am aware of the HUD Permanent Foundations for Manufactured Homes Publications.
It just makes sense that the roof structure is part of the the main wind force-resisting system and should be designed as such. It resists uplift, resists lateral load from the walls and serves as a diaphram for the structure. The ASCE-7 Standard seems to be very conservative in there analysis...
The Guide to the Use of the Wind Provisions of ASCE 7-02 indicates (in FAQ) that flat roof trusses should be designed as C&C. If these trusses(or joists) bear on masonry walls or beams, can the walls and beams and anchorages be designed for the MWFRS loads? The FAQ on gable trussses would seem...
Should the depth of pile caps be below frost? I seem to remember that being the case but I can find no codes, standards or guides stating that to be the case.
The 2004 CMAA 74 has some formulas for calculating lower flange bending stresses in monrail beams. Are these formulas correct? A previous Eng-Tip (2/6/03) indicated that there may be errors in the formulas. CMAA 74 does not give any theory behind the formulas. I have a old ACCO Chain and Lifting...
