Answer Happy

Part G
dG = 160 mm
tG = 9 mm
Part G - There are 5 questions in this part Refer to your email from Tim which defined values of the different variables for a rectangular hollow section, with outer external sides 2dG (height in mm) x dg (width in mm), and thickness to (in mm). You should assume all corners are perfectly square. The RHS is made from steel (E = 200000 MPa), and is filled with concrete (Ec = 25000 MPa). You should assume both materials exhibit linear elastic behaviour. The concrete cracks in tension at 5.75 MPa. The RHS is used as a beam, bending about the horizontal axis.

Question 17 1 pts Question G1 Transform the material to be all steel. What is the second moment of area of the transformed section about the horizontal centroidal axis (in mm4) ? Ignore the effect of the corner radii between the flange and web (ie assume all intersections are perfect right angles). You will not be able to enter your answer using exponential powers of 10 - eg if the answer is 3.456 x 106 you would need to enter 3456000. Question 18 2 pts Question G2 What positive bending moment (in kNm) would make the concrete crack in tension?

Question 19 Question G3 What is the maximum tension stress in the steel (in MPa) when the concrete cracks? Question 20 1 pts Question G4 Now consider a different bending moment that creates a maximum tension stress of 15 MPa in the steel. What is the maximum tensile strain (in microstrain) in the concrete? 1 pts