EVALUATING STANDARD INSTALLATION PRACTICES USED WITH VIBRATING WIRE PIEZOMETERS

I determined that several procedures typically used while installing Vibrating Wire Piezometers (VWP’s) are potentially unnecessary. In laboratory conditions, I varied the types of installation methods for VWP’s and measured their response time to increases in pressure. I found that some of the unaccepted methods for installing VWP’s produce accurate pressure data with minimal response times. I undertook this research to test the necessity of the typical recommended installation methods for VWP’s. Some common practices of VWP installation can be inefficient and challenging. By showing that some of these installation methods are unnecessary, we can save time on installations, and have a greater chance for the installation to be successful. Installation methods tested for this project and found to give accurate data include: VWP diaphragm up and then down in water, VWP with air pocket introduced into diaphragm and positioned down in water, VWP diaphragm positioned up and then down in sand, (both in and out of a canvas bag), VWP diaphragm positioned up and down in cement-bentonite grout, (both in and out of a canvas bag). I also performed tests on VWP’s installed in clay, with inconclusive results.