This lecture is very informative and helpful Before i watched this, from the textbook i couldn't get the meaning of back pressure and B value, which made me annoyed. Just amazed how i can clearly understand the process now.
Prof Kitch... thank you for the amazing lecture. May i ask a question? What should i check if the pore water pressure can't reach high to get the B value that i expected? Thank you.. I hope you will reply.
Many thanks to Prof. Kitch. It's highly informative and I learnt a lot. Q1: Since the back pressure of 60 psi plus cell pressure of 80 psi is not enough to achieve 100% saturation, what is the correct steps to follow to improve the saturation further? Is it correct that, say, raising to 100 psi for back pressure and 120 psi for cell pressure (always remaining a differential pressure of 20 psi as the effective consolidated pressure that have already applied to the speciemen), then openning all the valves to let the spaciemen consolidate further? Q2: Is this the sequence that consolidation process is followed by back pressure saturation and B-value measurement? Isn't it supposed to just perform the opposite?
you can do that if your pressure panel can supply pressure effectively at 120 psi. Also, you can allow the set up to stay for some time, since saturation is a function of both time and pressure.
It may or may not matter, but shouldn't the saturation be checked before starting the consol phase of testing? I'm basing this off of the procedure outlined in ASTM D4767.
I commented on this earlier. Yes, normally one should do the saturation phase before consolidation. For this particular soil, silty sand, there's not a lot of consolidation and for the purposes of the class I didn't want to wait for saturation before consolidation.
hello prof. kitch..is it ok to keep top drainage line open during early stage of saturation, if my back pressure line is connected to bottom of cell? i guess this will allow faster removal of air from sample.
Prof. Kitch you are a very good teacher! blessed. I learnt alot only from your one video. Keep on posting.
Awseome, i'am Brazilian and love you videos, good work and hugs for you!!
This lecture is very informative and helpful
Before i watched this, from the textbook i couldn't get the meaning of back pressure and B value, which made me annoyed.
Just amazed how i can clearly understand the process now.
jjalgu get a copy of part 3 from the lab Manuels from Head.
@@altviooltje K. H. Head’s three books on geotechnical lab testing are excellent references.
Prof Kitch... thank you for the amazing lecture. May i ask a question? What should i check if the pore water pressure can't reach high to get the B value that i expected? Thank you.. I hope you will reply.
Thanks
Many thanks to Prof. Kitch. It's highly informative and I learnt a lot.
Q1: Since the back pressure of 60 psi plus cell pressure of 80 psi is not enough to achieve 100% saturation, what is the correct steps to follow to improve the saturation further? Is it correct that, say, raising to 100 psi for back pressure and 120 psi for cell pressure (always remaining a differential pressure of 20 psi as the effective consolidated pressure that have already applied to the speciemen), then openning all the valves to let the spaciemen consolidate further?
Q2: Is this the sequence that consolidation process is followed by back pressure saturation and B-value measurement? Isn't it supposed to just perform the opposite?
Good day, I also confused about that. ASTM said that previously it should be saturated and then consolidated. Are you conducting CU test?
if you saturate and consolidate at the same time, it will be difficult to calculate the specimen's dimensions after consolidation.@@almasbisserik4991
you can do that if your pressure panel can supply pressure effectively at 120 psi. Also, you can allow the set up to stay for some time, since saturation is a function of both time and pressure.
sir, how much time it take to saturate compacted clay spacimen to denser state?
It may or may not matter, but shouldn't the saturation be checked before starting the consol phase of testing? I'm basing this off of the procedure outlined in ASTM D4767.
I commented on this earlier. Yes, normally one should do the saturation phase before consolidation. For this particular soil, silty sand, there's not a lot of consolidation and for the purposes of the class I didn't want to wait for saturation before consolidation.
hello prof. kitch..is it ok to keep top drainage line open during early stage of saturation, if my back pressure line is connected to bottom of cell? i guess this will allow faster removal of air from sample.
Yes, that is the top and bottom drainage lines are connected via a jumper. Not really shown in the video.
@@introductiontogeotechnical4976 thank you professor.