Question

PROBLEM Authorities of the Atherton Tablelands in North Queensland proposes a glass covered 3m long walkway scenic lookout to cater for tourists. The glass panels are to be attached to an aluminium frame attached to a reinforced concrete beam. You are required to design the reinforced concrete beam Gla Safety post up Thick glas SIDE VIEW FRONT VIEW Figure 1. Schematic View of the Walkway Structure To hold the aluminium frame/glass panels and to allow the tourists to walk in line, rest and enjoy the sceneries, a supporting reinforced concrete cantilever beam is conceived. Initial trials have provided the best possible dimensions for the RC beam as shown in Figure 2 L00 195 250 150 Figure 2. RC beam The loading on this cantilever structure was calculated as below Loading imposed by the glass panels and aluminium frame-11.6 kN/m .Loading imposed by tiles on slab and web of the beam-1.33 kN/m Loading imposed by the tourists- 16 kN/m Loading imposed by the safety reflector post at tip of the structure- 2 kN Loading imposed by the maintenance crew at tip of structure- 10 kN It was decided to use 40mm clear cover and 40MPa grade concrete (unit weight 25 kN/m Questions () Draw the plan view of the facility and the structure (2) Check the effective width of the flange of the beam as per CI. 8.8.2, AS3700(2018) (3) Determine self-weight in kN/m (4) Determine the magnitude of the uniformly distributed G load (5) Determine the magnitude of the uniformly distributed ultimate design load w (6) Determine ultimate point load at tip of the beam P mine design ing momen (8) Determine short term bending momentMo (9 Determine long term bending moment M (10) Determine direct and flexural tensile strengths of concrete () Determine the area of steel required for the calculated M 12 Arrange the steel bars appropriately and determine the e/e distance between bars (13 Determine the gross second moment of area of the cross-section I (14) Determine the cracked second moment of area of the cross-section (15) Determine the cracking moment M (16 Determine steel stresses at serviceability stage (17) Check if the steel stresses in (16) satisfy 0.3mm crack width intended consistent with CI. 8.6.22, AS3700 (2018) (18) Determine crack spacing (19) Determine crack width and check if it is lower than 0.3mm. If not, why not and how will you ensure crack width does not exceed 0.3mm? Select allowable limit of deflection from CI. 2.3.2, AS3700 (2018) Calculate deflection of beam and check if it is less than allowable; if not, suggest method for improvement (20) (21) (22) Calculate design shear force and determine the ultimate shear capacity required from the cross section dimensions and strength of concrete (23) Determine Vuman and comment on the potential safety of beam to shear (24) Design required stirrups (25) Show detailed sketches suitable for the construction engineer

Answer 1

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