Response of Members Subjected to Shear Flashcards
What happens to the shear stress as flexural capacity increases?
It decreases
What is the cause of shear in a member?
Change of moment
How many equations does the Compression Field Theory require you to solve to predict the response of a member in shear
10
How many equations does the Modified Compression Field Theory require you to solve?
15
What software package can you use to solve the equations in the MCFT?
MEMBRANE
What cross-sectional property is influenced by the size effect factor between the depth and width of a member?
The depth
Do larger members fail at comparatively lower stresses than smaller members?
Yes, this is why the size effect matters
What is the difference between the CFT and MCFT?
The inclusion of tensile stresses in the concrete after cracking
In CFT f1=0
In MCFT f1 not zero
If there is no reinforcement in the Z direction what is vci (shear stress on crack interface) equal to?
Applied shear stress v
What is the difference between a web-shear crack and a flexure-shear crack?
Web-shear cracking is a diagonal crack due to shear stresses in previously uncracked sections
Flexure-shear cracks form due to an extension of a flexural crack in cracked section
What changed between Morsch’s maximum shear stress formula and the ACI Code’s nominal shear stress formula for reinforced concrete beams
The lever arm from jd to d
Morsch v=V / bw j d
ACI Code v=V / bw d
Is the formula for cracking shear stress the same for web-shear cracks and flexure-shear cracks?
Nope
Two different formulas required
What 2 phenomena ensures that shear stresses are transmitted across flexural cracks?
1- Aggregate interlock
2- Dowel forces in flexural reinforcement
Does one type of diagonal crack occur before the other?
No, web-shear cracking can occur near the support first or flexure-shear cracking near the quarter of the span first
Cracking is a function of what strength?
Tensile or compressive strength of a member?
Tensile strength