HomeMy WebLinkAbout2016-11-07-COD-minCommission on Disability
Sub - Committee Minutes — November 7, 2016
Members Present: Victoria Buckley, Chair; Michael Martignetti, Shaun Grady
Town Liaisons: Linda Vine, Deputy Town Manager; Joe Pato, Selectman; Dave
Cannon, Assistant Town Engineer; David Pinsonneault, Public Works Director
Guest Speaker: Craig Dauphinais, Massachusetts Concrete & Aggregate
Producers Association (MaCAPA) - Presentation about Sidewalk Materials
Residents: Bob Adams (HDC), Nancy Adler, Joel Adler, Elizabeth Brach, Fred
Johnson, John Frey (Tree Committee), Maura Redmond [Douglas House (DH)],
John Long (DH), Steve Alibrandi (DH), Cynthia Janik (DH Program Manager),
George Burnell
Meeting was set up to hear Craig Dauphinais speak about concrete. It was
intended to be a sub - committee meeting open to the public and to the Center
Streetscape Ad Hoc Committee.
Craig's organization represents concrete and aggregate producers and other ready
mix suppliers, and their role is related to outreach and education. He has worked
in the field at all levels for over 29 years. He is a selectman in Grafton.
He discussed concrete qualities:
• versatile — designs, colors, finishes
• durable — resists freeze -thaw cycles and salts, resists loads
• strong — up to 40K psi
• rigid pavement, cool, bright (energy - efficient)
• very low maintenance and life cycle cost benefits — if done right
• modern technology
To demonstrate longevity of concrete he showed photos of schools in Grafton,
intersection in Lancaster NY, sidewalks in Rochester and Mount Morris. Dave
Cannon DPW said East Lexington sidewalks are old concrete in good shape.
Concrete joints include: isolation joints — around poles etc; expansion joints;
construction joints — wider, with pins; control joints — hand - tooled are tool joints
and there are cut ones as well — to tell the concrete where to crack.
Craig talked about the "90- minute rule" — which means from the time
cement is mixed until it is installed. Temperature guides whether mixture is ready.
More water is used in base if sandy. Fiber mesh in mix helps with shrinkage and
cracking. There is a chemical spray surface retardant that helps concrete set
evenly.
There are stamped concretes that look like brick. DPW said that that surface
is in front of Liberty Mutual but Grain Mill Alley is stamped asphalt. The bid
specification should be to get through the first winter.
Seams should be 1/4 the depth of concrete. Slabs are 4" — DPW stated that
compacted base gravel is 8 ".
Pervious concrete was briefly discussed which helps with drainage and trees.
How do we specify concrete so it is "done right "? Pick the mix design to control
material, slump, and air entrainment. Use 6 -8" compacted base. In cold weather
pouring, you can use accelerators and in hot weather pouring you can use
retardants. There should be no issue putting two materials side -by -side if
installation is correctly done.
The NRMCA National Ready Mix Concrete Association has a "design
assistance program" which offers free design material.
Concrete shrinkage can happen in the first few days — the less water, the less
shrinkage.
Installers should have ACI certification and finishers' certification.
Minutes respectfully submitted by Victoria Buckley