FDOT Earthwork Construction Inspection Level I

Comprehensive practice flashcards covering course objectives, aggregate sampling, soil mechanics, moisture-density relations (Proctor tests), nuclear density testing, Speedy moisture testing, and Earthwork Records System (ERS) documentation for FDOT ECI Level I qualification.

What is the examination format and time limit for the FDOT Earthwork Construction Inspection (ECI) Level I qualification?

A 2-hour, 50-question multiple-choice written exam and hands-on proficiency testing.

What certifications and examinations are required prior to obtaining the ECI Level I qualification?

Passing the written examination, passing hands-on proficiency testing (Nuclear Density, Speedy Moisture, and ERS reporting), and holding a Nuclear Safety Certification.

What are the two standard pavement types recognized in FDOT roadway construction?

Flexible pavement (Asphalt, which is the most common) and Rigid pavement (Concrete).

How does the FDOT course define 'Earthwork'?

The portion of the project involving the excavation, placement, and compaction of soils and materials supporting the proposed roadway and utilities.

What is the primary role of a Quality Control (QC) Earthwork Inspector versus a Verification Earthwork Inspector?

The QC Inspector represents the Contractor and performs required QC sampling, testing, and recording in the Contractor ERS; the Verification Inspector represents the Department and performs independent verification sampling, testing, and recording in the Verification ERS.

What is the difference between a Standard Job Guide Schedule (JGS) and a Non-Standard JGS?

A Standard JGS covers conventional pay item contracts (Design-Bid-Build), whereas a Non-Standard JGS covers single pay item contracts (Lump Sum, Design-Build) or non-pay item jobs (Local Agency Project [LAP], SCRAP, SCOP).

When sampling aggregates from a stockpile, what is the purpose of pushing a board vertically into the pile as shown?

To prevent sloughing of material and avoid segregation while collecting a representative sample from the shelf below.

What procedure must be followed when obtaining roadway aggregate samples for Standard Proctor testing?

Locate sampling stations using the random number generator, sample after spreading and before compacting, obtain at least three approximately equal increments across the roadway width (left, center, right) to full depth excluding underlying material, and combine to form a representative sample.

How must roadway samples be gathered when testing for soil organic content per FM 1-T 267?

Collect three separate subsamples across the roadway width (left, center, right) individually without mixing or combining them, test each separately, and average the three individual results.

What are the standard definitions of a 'Lift' and a 'LOT' in FDOT earthwork operations?

A Lift is a layer of material typically not more than $6\text{ in.}$ compacted thickness (maximum $12\text{ in.}$ depending on soil/operation). A LOT is a single lift of finished embankment not to exceed $500\text{ ft}$ for mainline/ramps/culverts/MSE walls, or $2000\text{ ft}$ for shoulder-only, shared use paths, and sidewalks.

According to the AASHTO Soil Classification System, which groups comprise Granular Materials versus Silt-Clay Materials?

Granular Materials ($\le 35\%$ passing the $75\,\mu\text{m}$ / No. 200 sieve) are classified as A-1, A-2, and A-3; Silt-Clay Materials ($> 35\%$ passing the $75\,\mu\text{m}$ sieve) are classified as A-4, A-5, A-6, and A-7.

How is Group A-8 soil classified and why is it unsuitable for roadway embankment and subgrade construction?

It consists of highly organic peat and muck identified by visual inspection (fibrous texture, dark brown or black color, and decay odor); it is unsuitable because it is highly compressible and possesses low strength.

What are the specific parameters measured in the AASHTO T 89 Liquid Limit test?

The moisture content at which a groove drawn in a soil paste placed in a brass cup closes over a distance of $0.5\text{ in.}$ after 25 drops at a rate of 2 drops per second.

What are the three physical changes that occur in soil as a result of compaction?

An increase in unit weight, a decrease in compressibility, and a decrease in permeability.

What are the test parameters of the Standard Proctor test (FM 1-T099) compared to the Modified Proctor test (FM 1-T180)?

Standard Proctor uses a $5.5\text{-lb.}$ rammer with a $12\text{-in.}$ drop (25 blows/layer in 3 layers) for embankment and pipe backfill; Modified Proctor uses a $10\text{-lb.}$ rammer with an $18\text{-in.}$ drop (56 blows/layer in 5 layers) for base, stabilized subgrade, and MSE wall backfill.

What radioactive isotope is utilized as the radiation source in nuclear moisture-density gauges, and what radiation is emitted?

Cesium-137 ($\text{Cs-137}$), which emits gamma radiation in the form of photons.

How do gamma photon counts detected by a nuclear gauge relate to material density?

The denser the material, the more electrons scatter the photons, resulting in fewer photons reaching the detectors; therefore, lower counts indicate higher density.

What is the difference between Direct Transmission and Backscatter modes in a nuclear density gauge?

In Direct Transmission, the source rod is lowered to the desired test depth into a pre-formed hole (used for soils, subbase, and limerock base); in Backscatter, the source rod remains retracted inside the gauge and relies on scattered photons (used for asphalt).

What equipment items are included in the nuclear density gauge testing kit shown?

Nuclear moisture-density gauge, standard reference block, scraper plate/drill rod guide, drill rod, extraction tool, hammer, and transport case.

How frequently must a nuclear density gauge undergo full calibration under FDOT requirements?

Annually (every 12 months), or whenever recalibration is deemed necessary by the DRSO or confirmed designee.

What distance and surface requirements must be observed when taking daily standard counts with a nuclear density gauge?

Place the reference standard on compacted soil ($\ge 100\,\text{pcf}$), asphalt, or concrete, at least $10\text{ ft}$ away from any large object and at least $30\text{ ft}$ away from any other nuclear gauge.

What are the acceptable day-to-day percentage tolerances for nuclear gauge Daily Standard Counts?

$\le 1\%$ shift for Standard Density Counts and $\le 2\%$ shift for Standard Moisture Counts when compared to the average of the previous four standard counts.

What surface preparation criteria must be met before placing the nuclear density gauge for a test?

Select a smooth test site with at least $6\text{ in.}$ clearance from any vertical projection, remove loose debris, and fill voids deeper than $1/8\text{ in.}$ using native fines or fine sand (never concrete sand).

How deep must the drill rod hole be driven for a nuclear density test, and how must the rod be removed?

Driven perpendicular to the prepared surface to at least $2\text{ in.}$ deeper than the desired test depth; removed by rotating and pulling straight up (never tapped loose with a hammer).

What materials are approved by FDOT for direct in-place moisture determination using an approved nuclear moisture-density gauge?

Limerock, cemented coquina, and shell-rock base materials.

What mathematical formula calculates in-place dry density from nuclear wet density and Speedy percent moisture?

$$\text{Dry Density} = \frac{\text{Wet Density} \times 100}{100 + \%\,\text{Moisture}}$$

What mathematical formula calculates the Percent Maximum Density?

$$\%\,\text{Max. Density} = \frac{\text{Dry Density} \times 100}{\text{Proctor Maximum Density}}$$

What are the required recording accuracies for wet density, percent moisture, dry density, and percent maximum density?

Wet density to the nearest $0.1\,\text{PCF}$, percent moisture to the nearest $0.1\%$, dry density to the nearest $0.1\,\text{PCF}$, and percent maximum density to the nearest whole percent ($1\%$).

What field testing device and kit components are pictured?

The Speedy Moisture Tester kit (Calcium carbide gas pressure moisture tester, tared scale, steel balls, reagent scoop, cleaning brush, and transport case).

What chemical reaction takes place inside the Speedy Moisture Tester during testing?

Free moisture in the soil reacts with calcium carbide reagent to produce acetylene gas and calcium hydroxide (lime).

How frequently must the Speedy Moisture Tester body and tared scale be calibrated?

Every 6 months; the tared scale must also be verified daily by the technician using certified check weights.

How many steel balls and scoops of calcium carbide reagent are added to a 20-gram versus a 26-gram Speedy Moisture Tester?

Two $1\frac{1}{4}\text{-in.}$ steel balls are used for both; 2 level scoops of reagent for a 20-gram tester, and 3 level scoops for a 26-gram tester.

What are the minimum shaking times when performing a Speedy Moisture Test on coarse soils versus heavy clay soils?

Approximately 1 minute for coarse, variable materials/soils, and approximately 3 minutes for heavy clay-type soils.

What adjustment must be made if the Speedy dial reading exceeds the maximum dial capacity ($20\%$)?

Re-run the test using half the standard sample weight ($10\text{ g}$ or $13\text{ g}$), double the resulting dial reading, and obtain the dry weight percent moisture from the applicable conversion chart.

What adjustment must be made if the Speedy dial reading indicates zero or is extremely low?

Re-run the test using double the standard sample weight ($40\text{ g}$ or $52\text{ g}$), divide the resulting dial reading by 2, and look up the corrected dry weight moisture on the conversion chart.

Why is the direct dial reading used without conversion when testing limerock with a Speedy Moisture Tester?

Because coarser limerock fractions are drier than the fine particles that enter the tester; using direct dial reading provides more accurate results without chart conversion.

What is the proper method for disposing of Speedy Moisture Tester chemical residue in the field?

Empty the residue directly onto open ground, spread it thinly away from buildings and flammable sources to allow unreacted reagent to decompose, and never place it into a waste bin.

What maximum dry density difference is permitted between gauges during an initial three-way equipment comparison?

$\le 2\,\text{lb/ft}^3$ between gauges from the same manufacturer, and $\le 3\,\text{lb/ft}^3$ between gauges from different manufacturers.

What rules govern two-way equipment comparisons conducted during production?

One gauge must be QC and the other VT (QC-to-QC and VT-to-VT are not permitted), and at least one of the gauges must have been previously verified through a passing three-way or two-way comparison.

From what point are lifts counted and numbered on an ERS embankment plot sheet?

From the bottom of the deepest excavation or greatest embankment fill section.

What policy governs error corrections on non-electronic Earthwork Density Reports?

Use a single-line strike-through with the corrected data written nearby and initialed; white-out, erasures, dittos, and arrows are prohibited.

What is the policy for candidates who fail an evaluation checklist item during the hands-on proficiency exam?

The student is allowed up to one additional evaluation on the same day; two failures in any single area constitute a failure of the proficiency examination.