Bachelor of Civil Engineering Flashcards

In prestressed concrete, post-tensioning differs from pre-tensioning in that:

Answer: Tendons are stressed after the concrete has hardened

In post-tensioning, tendons are placed in ducts and stressed against the hardened concrete after it reaches sufficient strength.

Which soil classification system is most widely used in geotechnical engineering practice in the United States?

Answer: Unified Soil Classification System (USCS)

The Unified Soil Classification System (USCS) per ASTM D2487 is the standard system used in geotechnical engineering to classify soils by grain size and plasticity.

The 'Bernoulli equation' in fluid mechanics assumes which of the following conditions?

Answer: Incompressible, inviscid, steady flow along a streamline

Bernoulli's equation is derived under the assumptions of steady, incompressible, inviscid flow along a streamline.

In structural steel design, the 'compact section' classification ensures that a beam can:

Answer: Develop full plastic moment without local buckling

A compact section has sufficiently stocky flanges and web to allow the section to reach its plastic moment capacity (Mp) before local buckling occurs.

Peak hour factor (PHF) in traffic engineering is used to:

Answer: Convert peak 15-minute flow rates to hourly volumes

PHF relates the highest 15-minute volume within the peak hour to the total hourly volume, accounting for traffic peaking within the hour.

The critical path in a project schedule (CPM) is defined as the sequence of activities that:

Answer: Determines the minimum project completion time

The critical path is the longest sequence of dependent activities, and any delay on it directly delays the project completion date.

Which type of pile derives most of its load-carrying capacity from skin friction along its length rather than tip resistance?

Answer: Friction pile

Friction piles transfer load to the surrounding soil primarily through interface shear (skin friction) along the pile shaft.