Brooklyn Queens Expressway
Services Applied by VCS Engineering
Project Description
The Brooklyn Queens Expressway (BQE) in New York City, New York, underwent a major rehabilitation which is being led by the Triple Cantilever Design Joint Venture (JV). As part of this work, VCS was contracted to perform concrete coring and laboratory testing along the BQE structures from Sands Street to Atlantic Avenue. The primary BQE structure in this area is the Triple Cantilever which carries three levels of traffic on a cantilever structure.
Project Issue
The structure along the BQE was experiencing severe corrosion and other reinforced concrete deterioration mechanisms. The JV was tasked with evaluating the structures and then developing an effective and efficient rehabilitation and service life extension. As part of that work, the JV required that core sampling and laboratory testing be conducted on the concrete so that the current condition could be determined and predictions regarding future deterioration could be made.
- ASTM C42 – Standard Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete
- ASTM C457- Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete
- ASTM C469- Standard Test Method for Static Modulus of Elasticity and Poisson’s Ratio of Concrete in Compression
- ASTM C642- Standard Test Method for Density, Absorption, and Voids in Hardened Concrete
- ASTM C876 - Standard Test Method for Corrosion Potentials of Uncoated Reinforcing Steel in Concrete
- ASTM C1152- Standard Test Method for Acid-Soluble Chloride in Mortar and Concrete
- ASTM C1218- Standard Test Method for Water-Soluble Chloride in Mortar and Concrete
- ACI 364.14T-17 Section Loss Determination of Damaged or Corroded Reinforcing Steel Bars
- ASTM A370 – Standard Test Methods and Definitions for Mechanical Testing of Steel Products
- ASTM C856- Standard Practice for Petrographic Examination of Hardened Concrete
The project included many logistical challenges, mainly regarding access, as the BQE is a critical vehicle artery for New York City. Most roadway closures could only be performed at night, and the work windows were short, around 4 hours, so the productivity each day was limited. VCS had a skilled field team that worked efficiently to collect all the cores on schedule and under budget.
Project Solution
VCS extracted 86 concrete cores along the structures and performed laboratory tests like compressive strength, chloride concentration, and petrography. This information was provided to the JV so that they could understand the current condition of the structures and develop service life models for its eventual rehabilitation.
