CIVL4120 – RESIDENTIAL FOOTINGS, TIMBER AND MASONRY DESIGN
2018 TIMBER DESIGN ASSIGNMENT
As a consulting structural engineer, The School of Newcastle has engaged your corporations to produce part of the structural design for a model new timber framed laboratory establishing. The establishing is to be designed to exactly duplicate the overall dimensions of an current laboratory establishing (Refer drawing DR9155123 – Portal physique shed.pdf). Nonetheless, the proposed new laboratory will use timber structural members, along with bracing, to Help steel purlins and girts and steel roof and wall sheeting. That’s in distinction to the prevailing establishing which makes use of steel structural framing.
GENERAL DATA
– The overall dimensions for the development are confirmed on the attached drawing.
– The associated Australian necessities are to be used.
– Roof and wall lifeless load (sheeting, purlins/girts, bracing and firms) = zero.three kPa – Roof imposed load = zero.25 kPa
– Earthquake info – earthquake loading is assumed to not be necessary for this building
– Wind info:
o Roof suction (North-South and East-West winds) 1.zero kPa (ultimate),
zero.55 kPa (serviceability) o Wall pressure (windward partitions) zero.85 kPa (ultimate), zero.5 kPa
(serviceability) o Wall suction (leeward and aspect partitions) zero.6 kPa (ultimate), zero.35 kPa (serviceability)
PORTAL FRAME: Design is required for the timber portal physique at Grid 2. The portal physique ought to resist gravity and wind plenty. The following data is obtainable:
– The portal members (columns C1 and rafters R1) are to be constructed using “Mixed Australian Hardwoods” – seasoned. The timber obtainable has a stress grade of F27.
– Assume that the timber is accessible in rectangular sections of width b = 120 mm and depths d starting at 190 mm and rising in 50 mm increments (that is, 190, 240, 290, and lots of others). Use the an identical cross half dimension for the columns and rafters.
– All design loadings for the development (in addition to column and rafter self weight) have been determined and are provided throughout the regular info (discover that these are forces per unit area acting on the roof and partitions).
– Knee braces (member K1 throughout the attached drawing) normally will not be to be used.
– The locations of purlins and girts are as confirmed on the attached drawings. Assume that purlins are hooked as much as the very best fringe of the rafters and that girts are hooked as much as the pores and skin fringe of the columns and that fly bracing shouldn’t be going to be provided.
Duties:
a. Analysis – Using Multiframe (or equal software program program) and the design plenty provided, analyse the portal physique to search out out necessary design actions for the columns and rafter (power limit state) and demanding physique deflections
(serviceability limit state). (10 marks)
b. Member Design – Determine an acceptable cross half dimension (b and d) for the columns (C1) and rafters (R1) of the portal physique to meet power and serviceability requirements. Current all assumptions and calculations. (10 marks)
c. Connection Design – Design a nailed connection for the second resisting connection between the column and rafter. (eight marks)
d. Current a summary of your design with engineering sketches exhibiting all associated data. (2 marks) Hints:
1. Every the columns and rafter are subjected to combined bending and axial actions along with shear.
2. The outcomes of size of load need to be thought-about for every the power and serviceability limit states.
three. For the Serviceability Prohibit State be sure that
Rafter sag beneath eternal loading G would not exceed span/250 the place the span on this case is the entire span from Grid A to Grid C.
Lateral column deflection (sway) at eaves stage on account of G + Ws would not exceed column peak/150
(neglect any deformations occurring throughout the joints)
CROSS BRACE:
Duties:
a. Design a timber cross brace to run from the very best of the column at A2 to the underside of the column at A3. The cross brace need to be designed only for the final phrase limit state (assume deflections normally will not be necessary). The cross brace is to be constructed from MGP15 (seasoned) timber. (4 marks)
b. Design and factor a 2 bolt connection between the timber cross brace and the column base at A3. (2 marks)

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