Problems 1 and 2 The truss below approximates a radio antenna tower. The blue vertical loads represent the weight of the
-
- Site Admin
- Posts: 899603
- Joined: Mon Aug 02, 2021 8:13 am
Problems 1 and 2 The truss below approximates a radio antenna tower. The blue vertical loads represent the weight of the
Summing forces on mounting point A: Summing forces on the upper joint: 4 +T, cos(76°) +T; cos( 70.3°) = 0 4, +T, sin (76°) +T; sin ( 70.3°) = 0 -T, cos(76°)+1cos ( 73.3°) + 200 = 0 -T sin(76°)-1; -T; sin (73.3°) - 500 = 0 T.cos(53.1°)-T, cos (70.3°) = 0 T: -1, sin (53.1°)-T; sin ( 70.3°) - 600=0 -T, cos( 73.3°) -T.cos(53.1°) = 0 ; T; sin ( 73.3°) +T, sin (53.1°) + B, = 0 Summing forces on the interior joint: Summing forces on mounting point B: 0 0 0 0 0 The resulting matrix equation: 1 o cos 76° 0 0 1 sin 76° 0 0 0 0 -cos 76° 0 cos 73.30 -sin 76° -1 -sin 73.30 0 0 0 0 0 0 0 0 1 0 0 0 0 0 -cos 73.30 0 0 0 0 sin 73.30 -200 500 cos 70.3° 074 sin 70.3° 04 0 07: 0 0 | T: -cos 70.3° 0 Tz -sin 70.3° 0 || T. 0 0|| T 0 В. 0 0 cos 53.19 -sin 53.1° -cos 53.1° sin 53.10 . 600 ) 1
Problem 2 Use Gauss Elimination with partial pivoting to calculate all of the tensions and reactions forces. Only perform row operations where necessary. eg in columns 1 and 2, all of the values below the diagonal are already zero, so there are NO row operations required in columns 1 and 2 Similarly, there will be only one set of row operations needed in column 3. There is an example of Gauss Elimination on Canvas, including the back substitution process to solve for [x]