Vibrating wire piezometer dry

[Rockdoc26]

Hi, I have to install an array of VWP's along the base of an old opencut quarry (approx. 90m deep)that is going to be filled with engineered fill. (houses built above) there will be there to monitor the infiltration rate and pore pressures. The only problem is that the Piezometers I am used to all need water in the filter during installation. It might be months before the water table (if it ever does) infiltrates to the VWP's (laid in a trench). And am concerned that they will dry out and when the water does eventually get to the VWP's the air bubble between the mesh and the sensor will remain and the data will be useless. will water eventually soak in through the Mesh (steel or ceramic)??(I didn't think it would)Ideas??

 

[Compositepro]

Air bubbles will not affect the reading. The pressure in an air bubble is equal to the water pressure surrounding the bubble. But if the soil is dry, there is no pore pressure.

 

[Rockdoc26]

Thanks for the reply. I have just been told that it could take up to a year for the water table to interact with the VWPs. So I was worried that if the VWP's small reservoir of water dried through capillary action or other action that when the WT eventually came that the data would be not accurate.

 

[GeoPaveTraffic]

Drying of the filter stone is a problem. One option would be to grout the piezometer in-place.

I suggest you talk with the manufacture and get their suggestion(s).

Mike Lambert

 

[L0k]

Place the piezometer in the water tank covered by geotextile and sandy gravel to avoid clogging.

 

[Rockdoc26]

Thanks for the replies. I'll keep updating with my progress. Cheers