CIVE 310 Exam 1 with Solution, Spring 2009

AMERICAN UNIVERSITY OF BEIRUT CIVE 310 Quiz1 – March 12th, 2009 Time Allowed: 15 minutes A stepped steel bar has a circular cross section and subjected to an axial loading P. The bar and its stress-strain diagram are shown in figures below. Determine approximately: . 1- The modulus of elasticity. 2- The load P in kN that causes the initial yielding of the bar. Initial yielding occurs at about 325 MPa. Since the sane load is applied to the stepped bar, we consider the smaller area (higher stress will be induced under the same P) 3- The load P in kN that causes failure (fracture). The load that causes failure is the maximum load that the bar can sustain (the load at the ultimate stress ) P P 4-The new length of the bar if 80 kN load is applied We shall treat each section of the bar separately. For section AB: For section BC: New Length: