California bearing ratio Flashcards
1
Q
What does CBR stand for?
A
California bearing ratio
2
Q
What is CBR primarily used for?
A
Assess the strength of materials used in or under pavementsand highways
3
Q
What is the CBR?
A
A ratio test to determine the relationship between force and penetration of a particular soil
4
Q
Which two penetration depths are the plunger loads divided at?
A
2.5mm
5mm
5
Q
What is the CBR equation?
A
(Measured force/standard force)x100
6
Q
When the load is calculated at the two penetration depths which is taken as the CBR?
A
The higher one
7
Q
A CBR value of <5% means
A
Weak soil, not good and needs improvement
8
Q
A CBR value of 5-15% means?
A
Good, strong soil, may need occasional grading
9
Q
A CBR value of 15-25% means
A
Very strong soil( no further work)
9
Q
A
10
Q
A CBR of 25 or over?
A
Hard soil, may be difficult to level off
11
Q
A
