A recent project location on the eastern end of Long Island in the Hamptons, NY, presented significant challenges with the 7’ diameter drilled shafts. MATRIX Construction Products was able to provide solutions to create a successful client experience.
SITE GEOLOGY: The subsurface geology on the Montreal jobsite consisted of soft silty clays (30+/-) changing to soft silts laying over a sandy gravel with black silt. The bedrock was a black competent sedimentary rock. Bedrock was only encountered at 12 locations.
CHALLENGE
MATRIX was contacted by a worldwide drilled shaft contractor operating in Canada that was unfamiliar with the process to drill shafts under polymer slurry. They were also unfamiliar with MATRIX products and services. They reached out to MATRIX after hearing positive feedback from other drilled shaft contractors about MATRIX products, solutions and their great experiences with MATRIX Field Support Services to train new customers in the uses of polymer drilling.
The customer had three major concerns that MATRIX was able to address:
1. Mixing, testing, and rebuilding of the polymer slurry
MATRIX provided an estimate for onsite training services for the field teams. The customer accepted the proposal and purchased a Slurry Test Kit, MATRIX Mixer, and MATRIX Slurry Sampler.
2. Clarifying the open shaft polymer slurry for downhole camera inspections
MATRIX discussed the variables and concerns with clarifying or flocculating the suspended solids in a polymer slurry. A review of which products would be required was also completed with the customer.
3. Disposal of the used polymer slurry
MATRIX provided the customer with detailed instructions on the neutralization and disposal of the wasted polymer drilling slurry.
SOLUTION
MATRIX provided four days of onsite instruction for proper mixing tank and equipment setup. As well as measuring and mixing instruction for polymer slurry products, proper technique to take slurry samples with the MATRIX slurry sampling tools and how to test and record information after using the MATRIX Slurry Test Kit.
Our MATRIX representative trained the customer in the proper use of air assist bottom hole vacuum system. The slurry worked so well that the bottom of the holes had almost nothing on them prior to installing the vacuum lines.
1 Training site crew on proper mixing
2 Training site crew on how to check viscosity of drilling fluids
3-6 Training site crew on building and using an “air line vacuum”
MATRIX also trained the customer to use FAST-FLOC in a drilled shaft to reduce sand content and pour shafts quickly to stay on schedule. FAST-FLOC was used for the final cleaning of the fluid and hole. The customer was extremely impressed with the FAST-FLOC results!
Measuring drilling fluid viscosity and checking sand content of drilling slurry
Amount of product used per 19,000 gallon tankful/batch:
M-BOOSTER® Dry pH Adjuster
150 lbs per 19K gals tank batches
FORTIFY® Slurry Loss Additive
100 lbs 19K gals
BIG-FOOT® Polymer Slurry
140 lbs 19K gals
These products were added directly into the drilling excavation when/if needed:
MOs-MUD® Strong Viscosity Booster @ 44 lbs / 10’ drilling in trouble zone (only 5ct x 44 lb cans used) in excavations where the groundwater and subsurface geology impacted and reduced the working viscosity of the BIG-FOOT Polymer Slurry system.
GEO-NET® Slurry Loss Circulation Material @ 60 lbs / 10’ drilling in trouble zone (none of this product was needed)
MATRIX personnel being easily accessible to the client regarding the issue, quickly traveling to the site, providing a strategic plan of action, and implementing that plan, created a positive outcome for our client. Both problem locations were drilled quickly to final depth in one eight-hour overnight shift.