Structural engineering help

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Will a timber beam deflect more than is safely permitted?
If a timber beam has dimensions of 225 mm by 75 mm and holds a UDL of 3.5 kN/m over a span of 4m. And If Young’s modulus for the timber is 10 kN/mm2, how much will the beam deflect?


A joist bending moment calculation?
A joist has section modulus 187.5 x 103 mm3 and the span is 3.8 m. It carries a Uniformly Distributed Load (UDL) of 1.7 kN/m.

What is the maximum bending moment for the joist
 

PhanthomJay

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Will a timber beam deflect more than is safely permitted?
A beam is not safe if its maximum stress exceeds the allowable stress for that material. The deflection is not safe only if the stresses are not safe, or if a Code requires a deflection limit (to prevent plaster cracking, for example, if it is a floor beam supporting a ceiling, or for appearance,unsightliness, etc.)
If a timber beam has dimensions of 225 mm by 75 mm and holds a UDL of 3.5 kN/m over a span of 4m. And If Young’s modulus for the timber is 10 kN/mm2, how much will the beam deflect?
Please show your attempt at a solution. What are the end conditions? Which way is the beam oriented? Beam deflections for uniform loads are given in tables, as a function of the load, span, elasticity modulus, and geometric properties of the beam; or can be calculated using calculus.


A joist bending moment calculation?
A joist has section modulus 187.5 x 103 mm3 and the span is 3.8 m. It carries a Uniformly Distributed Load (UDL) of 1.7 kN/m.

What is the maximum bending moment for the joist
Please show your work attempt, please.
 

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