Truss Problem 6.30: Urgent Help with Stress Calculation | 1020 Steel

[Pepsi24chevy]

truss problem, urgent help!

Hey guys i need help with setting up this truss problem 6.30 which can be seen here,
http://www.mustangmods.com/data/16002/study1.jpg

I know the stress in bc is 10.4ksi (tension) and that the safety facotr for it from 1020 steel is 4.038, I just need help figure out how to figure out that the stress is 10.4ksi. thanks

 

[lightgrav]

The Tension in CD is easy; find it.
Isolate upright member CE (Moments around pin E).

 

[quicknote]

Hi there,

Thank you for reaching out for help with your truss problem. I am happy to assist you with calculating the stress in this situation.

To begin, it is important to understand the basics of truss analysis. Trusses are structures made up of interconnected members, typically made of steel, that are used to support loads. In order to determine the stress in a truss member, we need to consider the forces acting on that member and the geometry of the truss.

In this specific problem, we are dealing with a truss made of 1020 steel. The safety factor for this type of steel is 4.038, which means that the maximum stress that this steel can withstand is 4.038 times the expected stress in the member. This safety factor takes into account potential variations in material properties and other factors that could affect the strength of the steel.

To calculate the stress in the BC member, we need to consider the forces acting on it. From the diagram, we can see that the member is in tension, with a force of 10 kips acting on it. To calculate the stress, we use the formula stress = force/area. In this case, the area is the cross-sectional area of the member, which can be calculated using the given dimensions of the member.

Therefore, stress = 10 kips / (2 inches x 3 inches) = 10 kips / 6 square inches = 1.67 ksi.

Since the safety factor for 1020 steel is 4.038, the maximum stress this steel can withstand is 1.67 ksi x 4.038 = 6.74 ksi. As we can see, the actual stress in the member (10.4 ksi) is higher than the maximum stress the steel can withstand, indicating that the member is under high stress and may need to be reinforced.

I hope this explanation helps you understand how to calculate the stress in a truss member. If you have any further questions or need assistance with any other aspects of this problem, please don't hesitate to ask. Good luck!