Tiêu đề TOS 2 - Virtual Work Method.pdf ✅

TOS 2: Virtual Work Method BLACKWATCH ENGR. PAUL L. LADESMA Civil Engineer | Materials Engineer 1 | Provisional Project Engineer Solve for reactions: ΣMC = 0 RA(7) − 7(4) (3 + 4 2 ) + 15(2) = 0 RA = 110 7 = 15.714 kN → A ΣFy = 0 RA − 7(4) + RC − 15 = 0 RC = 191 7 = 27.286 kN → C Create moment equations using ACTUAL load: ▪ For 0 ≤ X ≤ 4: ΣMCutting Plane = 0 M1 = A(x) − 7(x) ( x 2 ) M1 = Ax − 3.5x 2 ▪ For 4 ≤ X ≤ 7: ΣMCutting Plane = 0 M2 = A(x) − 7(4)(x − 2) M2 = Ax − 28(x − 2) X X RA M1 M2 RA RA RC


TOS 2: Virtual Work Method BLACKWATCH ENGR. PAUL L. LADESMA Civil Engineer | Materials Engineer 1 | Provisional Project Engineer Create moment equation using UNIT load: Unit load must be placed at the location where the slope or deflection is to be determined. If slope is to be Determined, use 1 unit rotation. If deflection, use 1 unit load. The direction of the unit load is taken as the positive direction Solve for reactions: ΣMC = 0 RA(7) − 1.0(2) = 0 RA = 2 7 ΣFy = 0 −RA + RC − 1.0 = 0 RC = 9 7 ▪ For 0 ≤ X ≤ 4: ΣMCutting Plane = 0 m1 = − ( 2 7 ) x m1 = − 2x 7 ▪ For 4 ≤ X ≤ 7: ΣMCutting Plane = 0 m2 = − ( 2 7 ) x m2 = − 2x 7 ▪ For 7 ≤ X ≤ 9: ΣMCutting Plane = 0 m3 = − ( 2 7 ) x + ( 9 7 ) (x − 7) m3 = −2x 7 + ( 9x 7 ) − 9 m3 = x − 9 RA RC X m1 RA X m2 RA X m3 RA RC 1.0