Question: 3 Stiffness Method - Truss. A simple truss is shown in Figure 4 . The truss supports a sign weighing 6 0 k N at

3 Stiffness Method - Truss. A simple truss is shown in Figure 4. The truss supports a sign
weighing 60kN at joint 1. Joints 2,3,4 are pin connected to a larger structure. The
length of each truss element is given in the figure. Assume AE is the same for members
1 and 3. Use 513AE for the vertical member. (25 pts).
A Create the member stiffness matrices for the three elements.
B Construct the structural stiffness matrix, displacement vector, and force vector for the
truss.
C Solve for the vertical and horizontal displacements at joint 1.
D Determine the vertical and horizontal reactions at joints 2-4.
E If joint 3 had a vertical settlement of 0.02m(downward), explain how this would
change the calculation and the results (no calculations required).
Figure 4 Structural Stiffness Matrix for Truss. Reference Material
k=[AELcos2+12EIL3sin(AEL-12EIL3)cossin-6EIL2sin-(AELcos2+12EIL3sin2)-(AEL-12EIL3)cossin-6EIL2sinAELsin2+12EIL3cos26EIL2cos-(AEL-12EIL3)cossin-(AELsin2+12EIL3cos2)6EIL2cos6EIL2cos4EIL6EIL2sin-6EIL2cos2EIL-(AEL-12EL3)cossin6EIL2sinAELcos2+12EIL3sin2(AEL-12EIL3)cossin6EIL2sin-(AEL-12EIL3)cossin-(AELsin2+12EIL3cos2)-6EIL2cos(AEL-12EIL3)cossinAELsin2+12IL3cos-6EIL2cos
-6EIL2sin61L2cos2EIL6EIL2sin-6EIL2cos4EIL]
-6EIL2sin
-(AEL-12EIL3)cossin
-(AELcos2+12EIL3sin2)
-6EIL2sin
-(AEL-12EIL3)cossin
-(AELcos2+12EIL3sin2)
-6EIL2sin
-6EIL2sin
-(AEL-12EIL3)cossin
-(AELcos2+12EIL3sin2)
-6EIL2sin
(AEL-12EIL3)cossin
ktruss=AEL[cos2sincos-cos2-sincossin2-sincos-sin2-sincoscos2sincos-sin2sincossin2]
-sincos
-cos2
sincos
kbeam=EI[12L36L2-12L36L24L-6L22L-6L212L3-6L22L-6L24L]
6L2
-12L3
6L23 Stiffness Method - Truss. A simple truss is shown in Figure 4. The truss supports a sign
weighing 60kN at joint 1. Joints 2,3,4 are pin connected to a larger structure. The
length of each truss element is given in the figure. Assume AE is the same for members
1 and 3. Use 513AE for the vertical member. (25 pts).
A Create the member stiffness matrices for the three elements.
B Construct the structural stiffness matrix, displacement vector, and force vector for the
truss.
C Solve for the vertical and horizontal displacements at joint 1.
D Determine the vertical and horizontal reactions at joints 2-4.
E If joint 3 had a vertical settlement of 0.02m(downward), explain how this would
change the calculation and the results (no calculations required).
Figure 4 Structural Stiffness Matrix for Truss3 Stiffness Method - Truss. A simple truss is shown in Figure 4. The truss supports a sign
weighing 60kN

Step by Step Solution

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Students Have Also Explored These Related Civil Engineering Questions!