PE Exam

[rania]

am searching and am not getting the answer , i appreciate it if any one can help me find the answer

the question is

DISSCUSS FOUR DIFFRENT TESTS OR PROCEDURES THAT ARE USED TO CHARACTERIZE THE PROPERTIES OF SUBGRADE SOILS AND THE IMPORTANCE OF THESE PROPERTIES IN DETERMINING THE PERFORMANCE OF THE OVERLY PAVEMENT .

AM GOING TO HAVE MY SECOND TIME OF PEO EXAM IN MAY THE 20TH .AND I FAILED FIRST TIME .. I REALLY APPRICATE IT IF ANY ONE CAN HELP FIND THE ANSWER

THANKS

 

[maryannette]

DISSCUSS FOUR DIFFRENT TESTS OR PROCEDURES THAT ARE USED TO CHARACTERIZE THE PROPERTIES OF SUBGRADE SOILS AND THE IMPORTANCE OF THESE PROPERTIES IN DETERMINING THE PERFORMANCE OF THE OVERLY PAVEMENT .

Okay, I'm not a soils expert, but the reason for testing subgrade is to ensure that it will support what is on top of it for a long time.

Soil classificataion, sieve analysis, Proctor compaction testing, Atterberg limits, moisture, plasticity ... there are others, but these are some of the more common ones that I know of. Results can tell you a lot about structural support potential and stability. I don't have any of my books at home. Maybe somebody else can elaborate. Hope this helps.

 

[rania]

Okay, I'm not a soils expert, but the reason for testing subgrade is to ensure that it will support what is on top of it for a long time.
Soil classificataion, sieve analysis, Proctor compaction testing, Atterberg limits, moisture, plasticity ... there are others, but these are some of the more common ones that I know of. Results can tell you a lot about structural support potential and stability. I don't have any of my books at home. Maybe somebody else can elaborate. Hope this helps.

thank u .. and i will keep checking if i will get another reply

 

[Guest]

Soil classificataion, sieve analysis, Proctor compaction testing, Atterberg limits, moisture, plasticity ... there are others, but these are some of the more common ones that I know of. Results can tell you a lot about structural support potential and stability. I don't have any of my books at home. Maybe somebody else can elaborate. Hope this helps.

Mary is spot-on, but I would look at it like this ...

Sieve Analysis

Determining the grain size determines the suitability of a 'support' for the overlaying pavement.

Atterberg Limits

Determine plasticity and liquid limit - also helps to classify the soil 'type' underneath.

Moisture Content

To determine how well compaction has been achieved for sub-base material.

Standard Proctor

Provides an indicator of the compactive 'effort' achieved for sub-base material.

The problem with an open-ended question - you were asked about lab tests vs. field tests. There are many 'tests' that can be run to evaluate the geotechnical properties of the soils.

Let me know if you have any specific questions. Good luck taking your exam!

JR

 

[txaggie]

if field testing is part of the quesiton...field density tests by a nuclear gauge is available.