Topic 13: Introduction To Construction Survey

Question 0

Standard Construction Equipment

Answer 0

Levels, tapes, total stations, gps.

Question 1

Why is construction survey needed?

Answer 1

For placing stakes for line and grade during construction. Ex: streets, sewer and water lines, structures.

Preparation of “as-built” maps

Question 2

Modern Technology Construction Equipment

Answer 2

1) Visible Laser-Beam: creates a visible line of known orientation or a plane of known elevation, benchmark.
2) reflectorless total station: employ a pulsed laser light to measure distances up to 100 m to objects without the use of a reflector.

Question 3

Staking out pipeline.

Answer 3

An offset reference line parallel to required centerline is first established (25-50ft stations)

Compute grade
Determine cuts or fills
Surveying report must convey two information: 
1) give depth of cut or fill. 
2) provide precise grade information.

Question 4

Examples of sources of error

Answer 4

Inadequate number and/or location of control points on job site. 
Errors of establishing control points 
Observational errors in layout
Careless referencing of key points
Movement if stakes and marks