## 3. Wooden joists are used to support a floor load of 6.95kPa exclusive of its own weight. The joists will have an effective span of 4.25m and be placed at 0.40m on centers. Weight of wood is 7.5kN/m2 A. Design the wooden joists so as not to exceed the allowable bending stress of 10.35MPa. B. Design the wooden joists so as not to exceed the allowable shearing stress of 0.85MPa. C. Design the wooden joists so as not to exceed the allowable deflection of 10mm. E=12135 MPa Hint: In designing joists (not beam) please follow next page for market size of joist. Also, in the design you have read the problem carefully. If the problem states to design economically then you have to consider the stress if it did not mention economically then go for conservative design.

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