An inverted T-section is being used as a lintel. The dimensions of the section are shown...

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An inverted T-section is being used as a lintel. The dimensions of the section are shown in Figure 3A. It is acting as a two-span continuous beam with uniformly distributed design loads applied as shown in Figure 3B. The bending moments have been determined for the design loads, and are also shown in Figure 3B. The centroid (y) is located 69.7mm from the base of the section. Ixx has been calculated to be 20.62*106 mm*. a) Determine the highest tension stress and the highest compression stress along the top edge of the lintel. State where along the length of the lintel each one occurs. b) Determine the highest tension stress and the highest compression stress along the bottom edge of the lintel. State where along the length of the lintel each one occurs. c) If the maximum allowable stresses in the lintel are: • compression stress along the top edge of the lintel: 280MPa compression stress along the bottom edge of the lintel: 320MPa tension stress along the top and bottom edges of the lintel: 320MPa 10, is the lintel able to support the design loads/moments? Assume all stresses are less than the yield stress. Ignore any lateral buckling effects or deflection limitations. 200 20 10 200 Figure 3 A Dimensions in mm Not to scale 6m 35 kNm maximum moment (2.7 metres from left hand support) 3.5 m -48 kNm at central support Figure 3B Dimensions in m Moments in kNm and drawn on the tension side Not to scale An inverted T-section is being used as a lintel. The dimensions of the section are shown in Figure 3A. It is acting as a two-span continuous beam with uniformly distributed design loads applied as shown in Figure 3B. The bending moments have been determined for the design loads, and are also shown in Figure 3B. The centroid (y) is located 69.7mm from the base of the section. Ixx has been calculated to be 20.62*106 mm*. a) Determine the highest tension stress and the highest compression stress along the top edge of the lintel. State where along the length of the lintel each one occurs. b) Determine the highest tension stress and the highest compression stress along the bottom edge of the lintel. State where along the length of the lintel each one occurs. c) If the maximum allowable stresses in the lintel are: • compression stress along the top edge of the lintel: 280MPa compression stress along the bottom edge of the lintel: 320MPa tension stress along the top and bottom edges of the lintel: 320MPa 10, is the lintel able to support the design loads/moments? Assume all stresses are less than the yield stress. Ignore any lateral buckling effects or deflection limitations. 200 20 10 200 Figure 3 A Dimensions in mm Not to scale 6m 35 kNm maximum moment (2.7 metres from left hand support) 3.5 m -48 kNm at central support Figure 3B Dimensions in m Moments in kNm and drawn on the tension side Not to scale