hello all,
Somebody asked me what is the covergence measurement use for what purpose and what is the alert level should be.
I am not really sure what is the correct answer and hope you guys can help.
My preliminary answer is
Purpose:
1) check the deformation and stability of the tunnel;
2)...
Thanks for BigH and Ron's kindly reply.
Actually, I am working on a tunnelling project, and 24hr working with 2 shifts will be carried out. As such some shotcrete may applied in the evening time and 8hrs after will be in the mid-night which result in really difficult to test at the laboratory...
Hello all,
I have to carried out the 8hrs strength test of the shocrete as the contract specification. As the time is tight, it is not possible to send the sample to laboratory for testing.
As such, I could like to ask is there any insitu testing method can do for that?
The specification...
thanks for yout reply,
yes, actually, I am looking for the cementious grout.
As the hole will be fill up with grout before the installation of steel bar, I wonder how could be the grout properties have to be for such grout for the horizontal hole and the hole in the crown.
I could imagine...
hello all~
I have an question on the Cement grout properties for Rock Dowel in tunnel support.
As I know that is common practices that the hole was grouted before the installation of dowel. To doing that the grout have to be viscosity enough or otherwise the grout will flow out from the hole...
thanks msucog's reply!!
Why I have this question is because I found that when searching in the internet, I can find both:
e.g.
http://dk.nanoq.gl/Service/Hoeringsportal/Milj%C3%B8vurderinger/2010/~/media/7DAFB26DAF514599AA993E244729B9CF.ashx
and...
effective cohesion = 20kn/m2 ??
are you sure it is not undrain shear strength?
If the effective cohesion = 20kn/m2, and you get -ve value for (Ka*soilunitweight*H)-(2*c*(Ka^1/2)), which means that the soil itself is stable for that 1 meter height. The retaining wall could be only for surface...
To calculate the bolt length for tunnelling support, I understand that the equation form Barton can be used. However, I found there two versions of the equation, which confuse me. I wonder any of you could know which is the correct one.
1) bolt length = (2+0.15B)/ESR
2) bolt length = 2 +...
Hello everybody,
I am facing the problem of checking the Secondary Compression(or called Secondary settlement/consolidation)calculation. The reason of checking is due to the secondary is seems too large, so that the settlement could excess the requirement during the maintainance period.
I had...
Jeff,
Thanks for your information. The FHWA paper give a estimation on the displacement.
However, there is no calculation on bending moment involved..... and the displacement is only rule of thurm as well
But anyway, thank you very much.
Thanks all of yours kindly reply. And yours kindly remind me that I am not provided enough information.
May I give more information and hope that you can help me to solve or give me some related information that I can read by myself.
the information are as follow...
Hello Everybody,
I am working on a Highways Project which inculding Embankment. As the ground contain thick clay and the embankment are high, part of embankment are decided to constructed with piled foundation. And this raise the question......
For those embankment with no piled foundation...