![]() ![]() The weight of the supporting framework W f, and the wind forceį w, all act through the center of the sign at Point A. Req'd : Determine the reaction forces and moments During a storm the wind pressure applies an equivalent force of 2200 Is 300 lb, the weight of the supporting framework is 600 lb, and the weight The bottom of the sign is 20 ft above the roadway. Given : A 14' by 8' road sign hangs over Hwy 101 near UCSB. m].īeams are covered in more depth in Chapter 6.From 0 to 4 m: Area = (2.4 N)(4 m) = 9.6 kN The lift capacity measurement of a crane tells us how much load a crane can lift naturally including the dimension of the load, lift height, and lift angle. The change in moment between two cross-sections is the negative in area under the shear diagram. To the right of the load, the bending moment decreases linearly from 9.6 kN From x = 0 to 4 m, the bending moment increases linearly from of 0 to 9.6 kN. ![]() To the right of the point load the shear force has a value of +1.6 kN. Between R 1 and the 4-kN point load, the internal shear force is constant: V = –2.4 kN (the negative sign indicates the shear force acts downward on a positive x-face, opposite drawn).V(x) and M(x) can be plotted on Shear Force and Bending Moment Diagrams. Positive sense of shear force and moment per convention of text. Sol'n : From the FBD of the entire beam, the reaction forces at the supports are found by taking moments about each end: SM x=0 = 0 –(4 kN)(4 m) + R 2(10 m) = 0Ĭheck: SF y= 2.4 kN + 1.6 kN – 4 kN = 0 OK Plot the results on Shear and Moment Diagrams. ![]() Req'd : Determine the shear force and bending moment distributions throughout the beam. Given : An I-beam shown is acted upon by a 4 kN point load 4 m from the left end. Sol'n : The forces P at the ends of the wrench arms causeĪ torque at Point C of T C = P(2a), which acts about the CD axis.įrom a FDD of shaft CD, the torque at C must equal A is the area of bending moment diagram between sections 1 and 2 and x is the distance of centre of gravity of A from the origin. The beam length will have to extend past the 4 metre distance required to move the load and so 4.2 metres has been selected. I have illustrated the shear force and bending moments on the beam. Req'd : Using the lug-wrench shown, determine force P to obtain the required Shear Force & Bending Moment Diagrams Depending on the location of the winch loads and stresses will vary. That it be tightened to a torque of 150 ft-lb. ![]()
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