Limerock Bearing Ratio Certification
What is the average bearing strength of base materials in Florida?
800
What is the jaw crusher set at to crush base material?
3/4"
If a sample has 60% passing the No. 4 sieve, what is the proportion for plus 4
and minus 4 material for a 6000-g sample?
3600g minus 4 & 2400g plus 4
What sieves do we use to grade a subgrade with?
2", 3/4", and No. 4
If the weight of the dry soil is 995.6 grams and the weight of the water is 63.4
grams, what is the percent of water in the sample?
6.4%
One cubic centimeter and one milliliter of water weigh the same. What is the
weight in grams?
1 gram
We have 5880 grams of dry soil. How much water do we need to add to bring the
moisture to 10.5%?
617 grams
You have 6240 grams of soil and you know it has 7.2% moisture. How much dry
soil do you have?
5821 grams
, After subdividing our sample, with increments of water added to them, how long
do they soak assuming the material is limerock?
24 hours
When determining LBR, to what part of the curve do we apply the tangent?
The greatest slope
When should the swell plate be placed on the specimen?
Before being placed into the tank
When specimens are in the soak tank, at what level should the water be
maintained?
within 1/4" of the sample height
What is the weight of the rammer?
10.00 ± 0.02lbs
What is the height of the drop of the rammer?
18 ± 1/16 inches
What is the diameter of the piston on the penetration machine?
2.00 inches
If the total load is 5,450lbs, what is the psi applied by the piston?
1817 psi
If the psi is calculated to be 1826, then what would the LBR be?
What is the average bearing strength of base materials in Florida?
800
What is the jaw crusher set at to crush base material?
3/4"
If a sample has 60% passing the No. 4 sieve, what is the proportion for plus 4
and minus 4 material for a 6000-g sample?
3600g minus 4 & 2400g plus 4
What sieves do we use to grade a subgrade with?
2", 3/4", and No. 4
If the weight of the dry soil is 995.6 grams and the weight of the water is 63.4
grams, what is the percent of water in the sample?
6.4%
One cubic centimeter and one milliliter of water weigh the same. What is the
weight in grams?
1 gram
We have 5880 grams of dry soil. How much water do we need to add to bring the
moisture to 10.5%?
617 grams
You have 6240 grams of soil and you know it has 7.2% moisture. How much dry
soil do you have?
5821 grams
, After subdividing our sample, with increments of water added to them, how long
do they soak assuming the material is limerock?
24 hours
When determining LBR, to what part of the curve do we apply the tangent?
The greatest slope
When should the swell plate be placed on the specimen?
Before being placed into the tank
When specimens are in the soak tank, at what level should the water be
maintained?
within 1/4" of the sample height
What is the weight of the rammer?
10.00 ± 0.02lbs
What is the height of the drop of the rammer?
18 ± 1/16 inches
What is the diameter of the piston on the penetration machine?
2.00 inches
If the total load is 5,450lbs, what is the psi applied by the piston?
1817 psi
If the psi is calculated to be 1826, then what would the LBR be?
