PROBLEM: A new architectural canopy is proposed to cover some portion of the ANZAC Square in...

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PROBLEM: A new architectural canopy is proposed to cover some portion of the ANZAC Square in Brisbane CBD. Figure 1 shows the schematic elevation of RC frame to support the top glass covering supported on the aluminium framing. The RC beam elevation and section are shown in Figure 2. For making it light weight, the depth of the beam is restricted to 300mm, while the width of the beam is proposed to be 200mm. You are required to design the RC beam by solving the questions given on the next page. Glass canopy RC Column 300mm (Typ.) RC Beam FRONT VIEW UDL from canopy Al supports Figure 1. Schematic View of the Canopy Structure 8m Elevation RC Column 300mm 200mm Section Figure 2. RC beam The loading on this RC beam was calculated as below: • Loading imposed by the glass panels and aluminium frame (WSIDL) = 10kN/m • Loading imposed by a person for maintenance (wo) = 2kN/m It was decided to use 35mm effective cover and 32MPa grade concrete (unit weight 25kN/m³). Take Ec 30,100 MPa and n = 6.6. - (1) Determine the self-weight of RC beam in kN/m (2) Determine the magnitude of the uniformly distributed permanent (wG) load Determine the magnitude of the uniformly distributed ultimate design load w* (3) (4) (5) (6) Determine the design bending moment M* Determine the short-term bending moment M; Determine the long-term bending moment Mus Determine the direct and flexural tensile strengths of concrete Determine the area of steel required for the calculated M* (TIP: Find Ast considering singly reinforced beam using ØM = M*. If this steel area does not satisfy the ductility requirements of AS3600, design a doubly reinforced beam keeping the same Ast and provide compression reinforcement for which the ductility and moment demand are satisfied) Determine the gross second moment of area of the cross-section Ig Determine the cracked second moment of area of the cross-section Icr Determine the cracking moment Mert Determine the steel stresses at serviceability stage Check if the steel stresses in (12) satisfy 0.3mm crack width intended consistent with Cl. 8.6.2.2, AS3600 (2018) Determine the crack spacing Determine the 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 the allowable limit of deflection from Cl. 2.3.2, AS3600 (2018) Calculate the deflection of the beam and check if it is less than the allowable limit; if not, suggest method for improvement. (18) Calculate the design shear force V* and determine the ultimate shear capacity Vuc of the cross-section Determine Vumax and comment on the potential safety of the beam to shear (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (19) (20) Design the required stirrups (21) Show detailed sketches suitable for the construction engineer PROBLEM: A new architectural canopy is proposed to cover some portion of the ANZAC Square in Brisbane CBD. Figure 1 shows the schematic elevation of RC frame to support the top glass covering supported on the aluminium framing. The RC beam elevation and section are shown in Figure 2. For making it light weight, the depth of the beam is restricted to 300mm, while the width of the beam is proposed to be 200mm. You are required to design the RC beam by solving the questions given on the next page. Glass canopy RC Column 300mm (Typ.) RC Beam FRONT VIEW UDL from canopy Al supports Figure 1. Schematic View of the Canopy Structure 8m Elevation RC Column 300mm 200mm Section Figure 2. RC beam The loading on this RC beam was calculated as below: • Loading imposed by the glass panels and aluminium frame (WSIDL) = 10kN/m • Loading imposed by a person for maintenance (wo) = 2kN/m It was decided to use 35mm effective cover and 32MPa grade concrete (unit weight 25kN/m³). Take Ec 30,100 MPa and n = 6.6. - (1) Determine the self-weight of RC beam in kN/m (2) Determine the magnitude of the uniformly distributed permanent (wG) load Determine the magnitude of the uniformly distributed ultimate design load w* (3) (4) (5) (6) Determine the design bending moment M* Determine the short-term bending moment M; Determine the long-term bending moment Mus Determine the direct and flexural tensile strengths of concrete Determine the area of steel required for the calculated M* (TIP: Find Ast considering singly reinforced beam using ØM = M*. If this steel area does not satisfy the ductility requirements of AS3600, design a doubly reinforced beam keeping the same Ast and provide compression reinforcement for which the ductility and moment demand are satisfied) Determine the gross second moment of area of the cross-section Ig Determine the cracked second moment of area of the cross-section Icr Determine the cracking moment Mert Determine the steel stresses at serviceability stage Check if the steel stresses in (12) satisfy 0.3mm crack width intended consistent with Cl. 8.6.2.2, AS3600 (2018) Determine the crack spacing Determine the 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 the allowable limit of deflection from Cl. 2.3.2, AS3600 (2018) Calculate the deflection of the beam and check if it is less than the allowable limit; if not, suggest method for improvement. (18) Calculate the design shear force V* and determine the ultimate shear capacity Vuc of the cross-section Determine Vumax and comment on the potential safety of the beam to shear (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (19) (20) Design the required stirrups (21) Show detailed sketches suitable for the construction engineer

Answer rating: 100% (QA)

1 The selfweight of a RC beam in kNm can be calculated by multiplying the beams unit weight by its length The unit weight of RC beam is typically around 25 kNm3 2 The magnitude of the uniformly distri... View the full answer