Тест 3.5 Cable Truss
Verification of the LIRA-FEM software / Тест 3.5 Cable Truss / Analytical solution: L. G. Dmitriev, A. V. Kasilov Cable Covers (Calculation and Construction), Publishers "Budivelnik", Kiev, 1968, pp. 75 - 81.
Analytical solution:Analytical solution: L. G. Dmitriev, A. V. Kasilov Cable Covers (Calculation and Construction), Publishers "Budivelnik", Kiev, 1968, pp. 75 - 81..
Geometry:
l = 40 м; h2 = 2.625 м; h3 = 4.5 м; h4 = 5.625 м; h5 = 6 м; F1 = 6 см2; F2 = 4 см2. |
Material characteristics: threads Е = 2 х 107 т/м2, vertical struts ЕF = 2 х 106 т.
Boundary conditions: Points 1 and 9 are fixed.
Stresses: P5 = 4 т, pre-stressing of the belt strands H = 10 т.
The girders of the truss were modeled by finite elements of a thread (FE 310-thread), 16 FE, vertical struts - 7 elements of a flat truss (FE 1).
CALCULATION RESULTS:
|
Point |
The desired value |
Analytical solution |
Calculation results (LIRA) |
uncertainty,% |
|
|
N1, т |
20,53 |
19,36 |
5,7 |
|
|
N2, т |
10,79 |
9,55 |
11,5 |
|
2 |
w2, м |
0,0895 |
0,0873 |
2,46 |
|
3 |
w3, м |
0,062 |
0,0527 |
15 |
|
4 |
w4, м |
-0,0825 |
-0,1075 |
30,3 |
|
5 |
w5, м |
-0,343 |
-0,395 |
15,16 |
Note: The analytical solution is obtained under the assumption that the forces N1 and N2 in the upper and lower chords of the truss are constant along the length. This assumption was not used in the calculation and the forces are not constant, which explains the difference between the calculation results and the analytical one.
Preview image: Array
Comments