Wrong Questions Flashcards
When sampling from a conveyor belt the inspector should:
Sample 3 equal increments and then recombine and mix
Gap graded soil is defined as?
1 sieve point or more missing from its particle distribution (also referred to as poorly graded)
Test specimens with what percentage of oversized material do not require a rock correction?
5% (ASTM D1557)
When sampling from a stockpile?
Sampling should be avoided without the use of power equipment, a flat board should be used to properly obtain sample, sampling should always be done @ varying elevations of the pile
Prior to placing fill over native ground what must occur?
Removal of vegetation and top soil is technically only thing that is required
When preparing a native surface for backfill what should be considered?
Scarifying the surface, removing any organic, benching slope areas if needed
When a rock correction is applied, the max dry density does what?
The oversized correction is for large particles so the max dry density will increase
A sheep’s foot compactor is most effective for compacting what type of soil?
Heavy clays but also sandy soils
The building official is permitted to waive the requirements for geotechnical investigation where:
Satisfactory data from adjacent areas is available that demonstrate an investigation isn’t necessary
Clays with a LL of less than 50 are labeled as? And where can you find this information?
CL or OL & it’s found in table 1 of ASTM D2487
Define “rough grading”
The general shaping of the earth and a site prior to establishing foundations and pavements
The standard penetration test (SPT) gives us?
An N-value
Define “Contour line”
A line connecting all points that share the same elevation
What equipment is best for pavement base courses?
Vibrating drum roller (also widely used for clays but is best w/ granular soil)
Thin-walled tubes are used in soil sampling?
Minimize the disturbance of the in-place material as it’s sampled
Plastic limit is?
The amount of water necessary to move soil from semi solid to plastic
Can non-plastic material be rolled into 1/8” worm?
If the material can’t be rolled into a 1/8” worm, it is not considered plastic
How far away from the nuclear desolate should other radioactive sources be when testing densities?
At least 30’ away
A relatively level area next to or excavated near a slope is?
A “bench”
When testing compaction in the trench it is necessary to?
Perform a correction to prevent artificial moisture readings from being added from the sidewalls , also should standardize the gauge in the trench
The ground immediately adjacent to the foundation must be sloped away from the building at a slope of what? And for how many feet?
It should slope away from the building at a slope of not less than 5% for a minimum of 10 feet
The definition of Rip Rap is?
Placing a stone or thin concrete on a sloped earth surface to protect against erosion
Definition for “silt”?
Material passing a No. 200 sieve down to clay sizes
How is the plasticity index calculated?
Liquid limit - plastic limit = plasticity index value
Are the bearing pressure capacities typically filled out on boring logs?
No, although they can be calculated from the information recorded on the boring logs
A final inspection report is submitted to who?
The building department (usually city department)
In which scenarios will soil have a dual classification symbol?
When it has 5-12% fines and when the plot of the LL & PI fall into the cross hatched area of the plasticity chart
During proof roll, pumping and yielding was observed after compaction efforts were performed. What is the next step?
The areas where pumping and yielding were found must be recompacted
Definition of “expansive soil”
Can expand in volume when subject to water and decrease in volume when dried
Definition of “Loess”
A wind borne deposit which has been cemented with an open void structure
What are some things that can negatively affect a sand cone test?
Vibration, irregular surfaces of the material side walls, large granular material
Why is a proof roll performed after compaction efforts?
To look out for pumping and yielding of the areas that did not receive compaction and moisture testing
