ETC Construction Methods & Equipment Flashcards

What is the primary purpose of shoring in an excavation?

Answer: To support the walls of an excavation and prevent cave-in

Shoring systems such as trench boxes, sheet piling, or timber shoring support excavation walls to protect workers from cave-in hazards.

What type of pile derives its bearing capacity primarily from friction along its length?

Answer: Friction pile

A friction pile transfers structural load to the soil through skin friction along the pile shaft rather than bearing on a hard stratum.

What equipment is commonly used to compact granular fill material in lifts during earthwork?

Answer: Vibratory roller

A vibratory roller combines static weight and vibration to densify granular soils and base materials effectively.

What is the minimum concrete cover for reinforcing steel in a slab not exposed to weather per ACI 318?

Answer: 0.75 inch (three-quarters inch)

ACI 318 requires a minimum three-quarters-inch cover for non-prestressed bars in slabs not exposed to weather when cast against stay-in-place forms.

What is the function of a motor grader on a construction site?

Answer: To fine-grade and level earthwork surfaces to precise elevations

A motor grader uses a long adjustable blade to cut, spread, and finish earthwork surfaces to specified grades and cross-slopes.

What does the slump test evaluate for fresh concrete?

Answer: The consistency and workability of the concrete mix

The slump test measures how much fresh concrete settles after removing a standard cone mold, indicating its consistency and water content.