ENG1001 Lecture Notes - Lecture 2: Sign Convention, Bending Moment
30 May 2018
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Course
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Week$2:$Equilibrium$&$Calc$of$Rctns$(moments)
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Document Summary
Week 2: equilibrium & calc of rctns (moments) Calculating numerical values for the rctns @ supports and forces in members of structure by using: the principle of equilibrium --> all forces must sum to zero. Based on fundamental req of a successful structure that: When loaded, a structure resists that load without collapsing. All structures deform when loaded, but they reach stable equilibrium. If this does not happen (aka equilibrium is not reached), the structure collapses. Lack of equilibrium is acceptable for rolling objects, but not structures, even on slanted slopes. Direction gives dir of applied moment, acc to rh screw rule. Select axis you are summing applied moments abt (i. e. the axis abt which you are checking for rotational eq) Wrap rh arnd this axis, w/ thumb along +ve x. Direction defined by fingers = +ve applied moment direction. If in equilibrium, no rotation abt any axis >>> free choice of the point abt which to take moments.
