The cantilever under-reinforced beam shown in Figure 1 carries a uniformly distributed live load Q =...

  

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The cantilever under-reinforced beam shown in Figure 1 carries a uniformly distributed live load Q = 6 kN/m and a superimposed dead load G = 3 kN/m, in addition to its self-weight (density is 2400 kg/m³). Moreover, a 30 kN permanent point P is applied at the right hand side of the cantilever. The width and the overall depth of the beam are 250 mm and 500 mm, respectively. The effect span L is equal to 3 m. The main reinforcement is composed of normal class N steel bars (E = 200000 MPa; fsy = 500 MPa). Steel bars in the compressive zone will not be accounted for in the USL design. The diameter of stirrups is 12 mm. h = 500 mm W b=250 mm L-3m Figure 1. Cantilever beam subject to uniformly distributed permanent and live loads. The building is a domestic residential building in Darwin (no fire requirements for this building). The exposure classification is B1 according to AS3600:2018. The characteristic compressive strength of concrete is 32 MPa. 1. Calculate the self-weight (S.W.) of the beam. 2. Calculate the design bending moment M'u for maximum loads. 3. Determine the effective depth d according to AS3600 durability requirement. 4. Design the tensile steel area Ast. 5. Select appropriate reinforcing bars and spacing. 6. Carry out the final ULS design checks. Based on the design above, answer the following questions below: Short term deflection using clause 8.5.3.1 and Equation 8.5.3.1(1) Effect of concrete shrinkage will be ignored 7. Calculate the design service bending moment M*ser for short-term. 1 8. Calculate the effective moment of inertia If and the short-term mid-span deflection of the beam using clause 8.5.3.1 and Equation 8.5.3.1(1). Long term deflection using clause 8.5.3.1 and Equation 8.5.3.1(1) Effect of concrete shrinkage will be included 9. Calculate the effective moment of inertia Iefusing clause 8.5.3.1 and Equation 8.5.3.1(1) and the long-term mid-span deflection of the beam. 10. Calculate the total deflection (short + long terms) and compare with AS3600 Service Limit State. Is the beam satisfying AS3600-2018 SLS requirement for control of deflection? The cantilever under-reinforced beam shown in Figure 1 carries a uniformly distributed live load Q = 6 kN/m and a superimposed dead load G = 3 kN/m, in addition to its self-weight (density is 2400 kg/m³). Moreover, a 30 kN permanent point P is applied at the right hand side of the cantilever. The width and the overall depth of the beam are 250 mm and 500 mm, respectively. The effect span L is equal to 3 m. The main reinforcement is composed of normal class N steel bars (E = 200000 MPa; fsy = 500 MPa). Steel bars in the compressive zone will not be accounted for in the USL design. The diameter of stirrups is 12 mm. h = 500 mm W b=250 mm L-3m Figure 1. Cantilever beam subject to uniformly distributed permanent and live loads. The building is a domestic residential building in Darwin (no fire requirements for this building). The exposure classification is B1 according to AS3600:2018. The characteristic compressive strength of concrete is 32 MPa. 1. Calculate the self-weight (S.W.) of the beam. 2. Calculate the design bending moment M'u for maximum loads. 3. Determine the effective depth d according to AS3600 durability requirement. 4. Design the tensile steel area Ast. 5. Select appropriate reinforcing bars and spacing. 6. Carry out the final ULS design checks. Based on the design above, answer the following questions below: Short term deflection using clause 8.5.3.1 and Equation 8.5.3.1(1) Effect of concrete shrinkage will be ignored 7. Calculate the design service bending moment M*ser for short-term. 1 8. Calculate the effective moment of inertia If and the short-term mid-span deflection of the beam using clause 8.5.3.1 and Equation 8.5.3.1(1). Long term deflection using clause 8.5.3.1 and Equation 8.5.3.1(1) Effect of concrete shrinkage will be included 9. Calculate the effective moment of inertia Iefusing clause 8.5.3.1 and Equation 8.5.3.1(1) and the long-term mid-span deflection of the beam. 10. Calculate the total deflection (short + long terms) and compare with AS3600 Service Limit State. Is the beam satisfying AS3600-2018 SLS requirement for control of deflection?

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1 Selfweight Calculation The selfweight of the beam can be calculated as follows Selfweight Volume x Density Volume Area x Length Area Width x Depth Area 025 m x 05 m 0125 m Volume 0125 m x 3 m 0375 m ... View the full answer