AZ ROC A (KA) Dual Engineering flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Arizona contractor license classifications

The ROC issues A (general engineering), B (general building), and C (specialty) licenses. A dual A/B license permits both engineering and building scope on a single license.

Mechanics' lien recording deadline

In Arizona, a mechanics' lien must be recorded within 120 days after completion of the project. Parties without a direct contract with the owner must first serve a 20-day preliminary notice.

Arizona retainage limit

On private construction projects in Arizona, retainage is capped at 10 percent of amounts due and must be released within 60 days after substantial completion of the work.

Swell factor

Swell factor equals (loose volume minus bank volume) divided by bank volume. It converts bank cubic yards of undisturbed soil to the larger loose volume after excavation.

OSHA soil types

Type A soil has unconfined compressive strength of 1.5 tsf or more; Type B is 0.5 to 1.5 tsf; Type C is less than 0.5 tsf or is granular, submerged, or previously disturbed.

Trench spoil setback

Excavated spoil must be placed at least 2 feet back from the edge of a trench to avoid surcharge loading that can cause wall collapse and to keep material from falling in.

Modified Proctor compaction

ASTM D1557 test that determines maximum dry density and optimum moisture content. Most structural fills specify 95 percent compaction relative to modified Proctor maximum density.

Water-cement ratio

The ratio of water weight to cement weight in a concrete mix. Lower ratios yield higher strength and durability; typical structural concrete uses 0.40 to 0.50.

ACI minimum concrete cover

Required cover over reinforcement: 3 inches when cast against earth, 1.5 inches for beams and slabs exposed to weather, and 0.75 inch for interior slabs not exposed.

Concrete cylinder test

Standard 6-inch by 12-inch cylinder cured and tested in compression at 28 days. The average of two cylinders must meet or exceed the specified compressive strength f'c.

Concrete curing duration

Moist curing for at least 7 days is required for Type I cement concrete to reach design strength. Cold weather below 40°F requires insulated forms or heated enclosures.

Ohm's law and power

V equals I times R; power P equals V times I, which also equals I squared times R. These formulas size conductors and calculate electrical loads on branch circuits.

Three-phase power formula

Kilowatts equal the square root of 3 times line voltage times line current times power factor, divided by 1000. Line-to-line voltage is used in this calculation.

Voltage drop limits

Branch circuit voltage drop should not exceed 3 percent of the source voltage. Combined feeder plus branch circuit drop should not exceed 5 percent total.

Refrigeration ton

One ton of refrigeration equals 12,000 BTU per hour of heat removal. Airflow rule of thumb for comfort cooling is about 400 CFM per ton of capacity.

GFCI and AFCI requirements

GFCI protection is required in bathrooms, kitchens, outdoors, and within 6 feet of sinks. AFCI protection is required in dwelling bedrooms and living areas per NEC.

Horizontal drain slope

Drain pipe 2½ inches and smaller must slope 1/4 inch per foot. Pipe 3 inches and larger may slope 1/8 inch per foot to maintain self-cleaning velocity.

Water closet fixture units

A private water closet counts as 3 fixture units and a lavatory as 1 fixture unit. Total fixture units determine required drain and water supply pipe sizes.

Vent stack roof termination

A vent stack must extend at least 6 inches above the roof surface and at least 12 inches above any window or opening located within 10 feet of the vent.

Backflow air gap

An air gap is the only backflow protection acceptable against a health hazard. Reduced-pressure zone (RPZ) assemblies protect against cross-connections to potable water.

Bolt hole diameter

Standard holes are 1/16 inch larger than the bolt diameter for bolts up to 1 inch, and 1/8 inch larger for bolts over 1 inch, per AISC requirements.

Fillet weld throat

The effective throat of a fillet weld equals 0.707 times the weld size. Capacity equals throat times weld length times allowable shear stress.

E70XX electrode strength

In the AWS electrode classification, the first two digits give minimum tensile strength in ksi. E70 electrodes have a minimum tensile strength of 70,000 psi.

Steel density

Structural steel weighs 490 pounds per cubic foot. W-shape designations give weight per linear foot, so a W14×90 weighs 90 pounds per foot of length.

CSI MasterFormat divisions

MasterFormat organizes specifications into 50 divisions. Division 01 is General Requirements, Division 02 is Existing Conditions, and Division 03 is Concrete.

Document precedence order

Written specifications govern over drawings, large-scale drawings govern over small-scale, and written dimensions govern over measurements obtained by scaling a drawing.

Critical path method

The critical path is the longest-duration sequence of dependent activities through the network. Any delay on the critical path delays the project completion date.

Estimate contingency

A contingency allowance of 5 to 10 percent is typical for design-bid-build estimates. Conceptual budgets use 10 to 20 percent for undefined scope.

OSHA fall protection threshold

Construction workers must be protected from falls at 6 feet or more above a lower level using guardrails, safety nets, or a personal fall arrest system.

Scaffold rail dimensions

Scaffold top rails are installed between 38 and 45 inches above the platform. Midrails are about 21 inches high and toe boards are 3½ inches tall.

SWPPP requirement

A Stormwater Pollution Prevention Plan under the NPDES Construction General Permit is required for construction sites that disturb 1 acre or more of soil.

Hazard Communication program

Employers must maintain a written HazCom program, keep safety data sheets accessible on site, and train every employee exposed to hazardous chemicals.