URGENT HELP REQUIRED!!! Calculate the Limiting Deflection; - A Timber floor supp

Question

URGENT HELP REQUIRED!!!

Calculate the Limiting Deflection;

- A Timber floor supported by 10 bearers, 295mmx80mm (depthxwidth)

- Bearers machine graded sawn, unseasoned Grey Ironbark (Strength Group S1, Stress Grade F17)

- Bearers Clear Span of 3.5m and the ends of the bearers sit on 100mm wide supports

- The compression flange of the bearers are restrained by joists at 450mm centers (Hint; Lay = 450mm)

- The spacing between bearers is 2.4m

- The live load applied along the length of the bearer has been calculated to be 3.0kN/m

- The dead load applied along the length of the bearer including self weight has been calculated to be is 1.5kN/m

FULL WORKINGS REQUIRED

Explanation / Answer

There are really two factors that control bearing strength.
1. Pull/Tear out
2. Bearing deformation

How to calculate each:
1. FailForce = ShearStrength * MaterialThickness * LengthOfTearOut
2. FailForce = CompresiveStrength * MaterialThickness * RivetDiameter

This assumes your rivet fills the hole completely. In addition, I wouldn't use this for a single lap joint. The lap joint will twist and the failure will occur significantly below the above formulas.
Instructions
1
Set up the algebraic equation: bearing stress (BS) = F/A. In this equation, F stands for how much force exists between the two contacting objects. If you are using SI units, the measure of force is in Newtons. In the U.S., use pounds to indicate the degree of force. The other factor of the equation is A, or the surface area where the two objects make contact. In SI units, use square meters to measure the area. In U.S. units, use square inches for the measurement.

2
Insert the measurement of force (F) into the equation. For example; if the force internally exerted between two objects is 10 lbs., your equation becomes BS = 10/A.

3.Insert the area measurement into the equation. Using the same example; if the area is 2 square inches, the equation becomes BS = 10/2.

4
Divide the force (F) by the area (A) to solve for bearing stress (BS). Continuing the same example; this results in 5 lbs. per square inch, or 5 psi. If, in this example, SI units are used, the end result is 5 Newtons per square meter, or 5 Pasquals

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