77-87 Commercial Street

The Big Apple Group (Big Apple) is proud to be a part of this project helping developers by not only meeting the various NYCDOB requirements but ensuring that every step of the way the adjacent structures are protected and tenant exposure to high vibrations is kept within thresholds.

Once completed, Waterview at Greenpoint will include three separate buildings along Brooklyn’s Greenpoint Waterfront. The development will consist of a 40-story and 296-unit residential building, a 30-story and 224-unit residential building, and a 6-story and 200-unit building for a combined 700+ residential units. Throughout the development there will be fully landscaped walkways to serve as community access.

Big Apple has been working closely alongside the developers from the moment Support of Excavation (SOE) operations were set to begin. For those of you who are new to the industry jargon SOE systems are temporary earth-retaining systems intended to control the soil to facilitate a safe and efficient space for construction. This is especially important for New York City where adjacent buildings are directly abutting a project where deep excavations and underpinning are requested by the Structural Engineer.

Cue the Big Apple Team!

We began our journey at 77 Commercial Street with a walkthrough of the adjacent structures. These walkthroughs usually provide a great starting point for client expectations and scope of work. In this case our team of Engineers, Inspectors and Field Technicians were on site to complete the walkthrough.

During this walkthrough we were able to identify properties in need of additional monitoring due to the existing conditions as well as mounting location for the Automated Total Station (AMTS) and seismic sensors which will keep a close watch for any preliminary structural issues that may develop with the adjacent structures. After some developer/tenant coordination, we were ready to design and implement our monitoring protocol in accordance with Section 3309 of the New York City Building Code. The monitoring protocol or monitoring plan represent the instrumentation requirements and monitoring procedures recommend by Big Apple for the protection and safeguarding of the structures adjacent to the project site. These services include but are not limited to Existing Conditions Survey for the adjacent properties, Optical and Crack Monitoring.

Existing Conditions Survey

For the adjacent properties Big Apple sends in an Inspector to document by digital photography the cosmetic and structural conditions of the existing adjacent structures. The purpose is to document any potential weakness or signs of structural distress and address the issues as needed.

Optical Monitoring

The construction of the Waterview at Greenpoint is monitored in a variety of ways. But when it comes to Optical Monitoring, also known as displacement or settlement monitoring, our team really exceeds where others fall short. Both Conventional and Robotic Total Stations are used to capture the full spectrum of possible movement at the adjacent structures which could be triggered by SOE operations.

Crack Monitoring

When it comes to protecting adjacent structures, Big Apple is the quickly becoming the industry’s go-to Civil Engineering firm for measuring cracks that may develop during the excavation and foundation construction phase and the Waterview at Greenpoint is a testament to that fact. Developers and adjacent building owners have entrusted our expertise for the installation, data collection and analysis of crack gauges that our team has installed in and around the adjacent properties. Big Apple carefully tracks the movement of these crack gauges and when combined with the optical data we are able to identify any settlement or displacement before it happens so that the contractors are able to adjust their work methods accordingly.

Vibration Monitoring

Human response to vibrations is very complex. The degree of annoyance one person feels is not always explained by the level of vibration recorded. For this reason, Big Apple Group has been brought on to the project site to monitor the construction vibrations and alert the project managers in real time, 24 hours a day.

Inspections

In retrospect the aforementioned items make up only part of the Civil Engineering services the Big Apple Group brings to the Waterview at Greenpoint Development located at 77 Commercial Street. At the time of writing, Big Apple is providing Materials Testing and Verification as well as Special Inspection Services; all of which ensure the Contractors are adhering to the various industry standards such as ASTM, AASHTO, CCRL and IAS. Compliance with these standards is the first step in complying with the New York City Department of Building Inspection Requirements.

Our Special Inspectors have been on-site with the construction performing the required Inspections. For this project we are conducting inspections on the following:

• Structural Steel – Welding, Details, High Strength Bolting and Cold-form Steel
• Concrete – Cast-In-Place, Concrete Placement Inspections
• Rebar Inspections
• Grout/Mortar Sampling and Testing
• Soil Compaction Testing
• Load Test Reports

For more information on how Big Apple can help your projects, or to learn more about how Construction Monitoring can protect your building, feel free to check out our website.