Project Description

Hands Free Mooring Slots Installation – Snell Lock – Saint Lawrence Seaway Development Corporation – USDOT

Scope: The installation of three sets of 75 LF vertical rails in the North Wall Monolith of Snell Lock – Massena, NY

Project value:  $6.9 million

Project duration per phase:

Phase I: November 2017 – March 2018

  • The installation and testing of 18 x 55 lf long post tensioned rock anchors
  • Demolition: 1,150 CY of concrete demolished using heavy duty grinders mounted on excavators operating from barges in the lock; demolition limits survey and corrections.
  • Concrete base and temporary concrete bulk heads pour

Phase II: January 2019 – March 2019

  • Temporary concrete bulk heads demolition
  • Dowel and anchor rods installation and testing in the vertical walls
  • Rails installation, alignment and survey
  • Pouring structural concrete: reinforcing bars installation, forming and concrete pouring in 3 lifts per slot, approximately 780 CY of concrete poured in total.
  • Electrical conduits and bubbler pipe system installation
  • Work on top of the deck: concrete pedestals (plinths) pouring, anchor bolts installation and testing

Project special conditions:

  • Work in the lock which is mandatory during the navigation off-season
  • Rail alignment within +/- 2 mm tolerance in all planes
  • Concrete pouring in heated enclosures due to extreme winter weather conditions

QCS performed the Third Party Inspection for this project with three inspectors covering the General Contractor’s schedule of 7 days per week working 12 hour shifts (day and night). Our General Construction Inspection duties included the following:

  • Post Tensioned rock anchors installation and testing inspection
  • Demolition limits assessment
  • Dowel and anchor rods installation and testing inspection
  • Rail alignment assessment during the alignment procedure and following survey
  • Reinforcing bars installation inspection
  • Concrete testing (all delivered concrete was tested on site) and concrete placement Inspection
  • Checking critical dimensions of slot geometry (during forming and corner protection plate positioning)
  • Conduits and bubbler pipe system installation inspection
  • Painted steel touch up operation inspection.