Paving & ADA
Paving is the biggest single section of the C-12 exam, covering both how pavement is built and the accessibility rules it must meet.
Asphalt vs concrete
Asphalt concrete (AC) is a flexible pavement: it flexes under load and spreads it to the base, costs less up front, and is quick to place and patch. Portland cement concrete (PCC) is a rigid pavement: a stiff slab that bridges over the subgrade, costs more, lasts longer, and uses joints to control where it cracks.
Coats: prime coat → onto an absorbent aggregate base; tack coat → between two asphalt layers. ADA: ramp running slope ≤ 1:12 (8.33%); accessible cross slope ≤ 2%; accessible parking needs an access aisle.
Building it to last — and to code
Compact hot-mix asphalt while it’s hot. The leading causes of early pavement failure are poor drainage / a saturated subgrade and inadequate compaction — which is why the earthwork underneath matters as much as the surface.
Public paving must also meet ADA accessibility: an accessible ramp runs no steeper than 1:12 (8.33%), an accessible surface’s cross slope stays at or below 2%, and accessible parking spaces include an adjacent access aisle.
Practice: Paving & ADA
Frequently asked
What is the difference between a prime coat and a tack coat?
What are the ADA maximum slopes?
Why is asphalt called flexible and concrete rigid?
More C-12 Earthwork & Paving topics
Planning & Estimating Earthwork
C-12 study guide on planning and estimating earthwork: reading plans, cut and fill, balancing a site, shrink and swell factors, percent grade, and project layout.
Read & practice →Soils & Compaction
C-12 study guide on soils and compaction: the Proctor test, maximum dry density, optimum moisture content, relative compaction, standard vs modified Proctor, and lifts.
Read & practice →Excavation & Grading
C-12 study guide on excavation and grading: the pavement structure (subgrade, subbase, base course), load distribution, benching fill into slopes, grade control, and trench backfill.
Read & practice →Excavation Safety (OSHA)
C-12 study guide on OSHA trench and excavation safety: when a protective system is required, soil types and slopes, the competent person, access and egress, spoil placement, water, and atmospheres.
Read & practice →Stormwater & Environmental
C-12 study guide on construction stormwater: when a site needs Construction General Permit coverage, the SWPPP and QSD/QSP roles, and erosion control vs sediment control BMPs.
Read & practice →Work-Zone Traffic Control
C-12 study guide on work-zone traffic control for paving and roadway jobs: orange signs, taper length, the flagger's STOP/SLOW paddle, and channelizing device spacing.
Read & practice →