In partnership with Navillus Contracting, Big Apple Group has been brought in to monitor construction activities with the goal of protection the adjacent structures, tenants and most important the students nearby from potential high vibrations and excessive building movement from the adjacent construction activities.
PS 195/196X is a new 55,000 square feet new addition construction project in Bronx, NY; it can accommodate grades K-5. The New York City School Construction Authority controls the construction management, the design is by PKSB, and Navillus is acting as the General Contractor for the project. The new five-story concrete superstructure has a precast panel envelope and includes aluminum windows and storefronts, new HVAC systems with RTUs, an emergency generator, a state-of-the-art kitchen, and three new elevators. New standalone services, gas, electric, sewer, and water services will be installed, in addition to fire protection systems, intrusion alarms, and fire alarms. The project also includes a new a rooftop play area. The building complies with ADA requirements and complies with the Local Law 86 of 2005.
The Navillus team has been been busy performing basement subgrade rock excavation, as well as underground piping installation and partial 1st floor slab installation. To ensure the protection of adjacent structures Big Apple has been developed a construction monitoring plan.
For optical monitoring aka settlement or movement monitoring, baselines have been established along the perimeter of the site to be utilized for the duration of the monitoring. Points will be set on the existing buildings at key locations and we will return to the site to obtain horizontal and vertical measurements for the displacement points set in the initial visit. “Telltales” also known as crack gauges have also been installed and monitored on any open joints in the permanent structures on neighboring properties. Ground-borne vibration is not a phenomenon that most people experience every day. Vibrations perceived as destructive by humans are typically much lower than the vibration levels that would be considered critical for structures. Big Apple has provided and installed the required remote vibration monitoring systems with alerts that go out on programmed review and limit levels. The purposes of the Review and Limit Levels is to: first alert the contractor if they are approaching the Limit Level so that they can modify their means and methods as necessary, and then to alert the contractor if a Limit Level has been exceeded.