Site Investigation

Question 1

What’s the typical location and spacing for boreholes for structures and roads and what is the minimum depth

Answer 1

Structures : 10-30m
Roads: 50-200m
Depth: 2x the width

Question 2

What are the main types of in-situ field tests?

Review the table

Answer 2

Spt standard pen test
Vst vane shear test
Cpt cone pen test
Pmt pressure meter test

Question 3

What are the common ways to measure groundwater?

Answer 3

Water well (stand pipe)
Vibrating wire
Pneumatic piezo meter
Hydraulic piezo meter

Question 4

What are the primary objectives of a site investigation?

Answer 4

Suitability of the site
Design 
Construction 
Effects of change
Site choice

Question 5

What are the pros and cons of using a water well?

Answer 5

Inexpensive
Allow for sampling
Reliable
Cons:
Long response time
Can't measure negative pore pressure

Question 6

What are the pros and cons of using a vibrating wire?

Answer 6

Pros:
Short lag time
Automated
Can read negative pore pressure
Cons:
Needs lightning protection, subject to errors

Question 7

What are the pros and cons of a pneumatic piezo meter?

Answer 7

Pros:
Short lag time, no drift issues, no freezing
Cons:
Time consuming, not automated, requires nitrogen and co2 gas