The Living Bridge Project


Living Bridge Overview

PFI:BIC: The Living Bridge: The Future of Smart, Sustainable, User-Centered Transportation Infrastructure

Funding: NSF (IIP 14-30260 )  + NHDOT (New Hampshire Dept of Transportation)

PIs: Erin Bell (PI), Tat S. Fu, Kenneth Baldwin, Martin Wosnik, Lawrence Hamilton

Duration: 2014-2017

Abstract                                                                                                                               

This Partnerships for Innovation: Building Innovation Capacity (PFI:BIC) project from the University of New Hampshire focuses on a “living bridge”, which exemplifies the future of smart, sustainable, user-centered transportation infrastructure. Bridges deliver such a fundamental service to society that they are often taken for granted. Typically, bridges only stir the public’s interest when they must unexpectedly be replaced at great cost, or, worse, fail. The Living Bridge project will create a self-diagnosing, self-reporting “smart bridge” powered by a local renewable energy source, tidal energy, by transforming the landmark Memorial Bridge–a vertical lift bridge over the tidal Piscataqua River, with pedestrian access connecting Portsmouth, New Hampshire to Kittery, Maine–into a living laboratory for researchers, engineers, scientists, and the community at large. The Living Bridge will engage innovators in sensor and renewable energy technology by creating an incubator platform on a working bridge, from which researchers can field test and evaluate the impact and effectiveness of emerging technologies. The Living Bridge will also serve as a community platform to educate citizens about innovations occurring at the site and in the region, and about how incorporating renewable energy into bridge design can lead to a sustainable transportation infrastructure with impact far beyond the region.

Sustainable, smart bridges are key elements in developing a successful infrastructure system. To advance the state of smart service systems and clean energy conversion, this project team will design and deploy a structural and environmental monitoring system that provides information for bridge condition assessment, traffic management, and environmental stewardship; advances renewable energy technology application; and excites the general public about bridge innovations. This PFI:BIC project is enabled through partnerships between academic researchers with expertise in structural, mechanical and ocean engineering, sensing technology and social science; small businesses with expertise in instrumentation, data acquisition, tidal energy conversion; and state agencies with bridge design expertise. The Living Bridge technical areas are structural health monitoring, tidal energy conversion with fluid-structure interaction measurements, estuarine environmental monitoring, and outreach communication. Sensors will be used to calibrate a three-dimensional analytical structural finite element model of the bridge. The predicted structural response from this model will assess the measured structural response of the bridge as acceptable or not. Instruments installed on the turbine deployment platform will measure the spatio-temporal structure of the turbulent inflow and modified wake flow downstream of the turbine. Resulting data will include turbine performance and loads for use in fluid-structure interaction models. Deployed environmental sensors will measure estuarine water quality; wildlife deterrent sensors will deter fish from the turbine. Hydrophones and video cameras will be used before and during turbine deployment to monitor environmental changes due to turbine presence. Outreach efforts will make bridge data, history, and information about new systems accessible and understandable to the public and K-12 educators, facilitated by an information kiosk installed at the bridge. Public awareness will be assessed with survey methods used in the N.H. Granite State Poll.

The lead institution is the University of New Hampshire (UNH) with its departments of Civil Engineering, Mechanical Engineering, and Sociology, and the Center for Ocean Engineering. Primary industrial partners are a large business, MacArtney Underwater Technology Group, Inc. (Houston, TX); and a small business, Lite Enterprises, Inc. (Nashua, NH). Broader context partners are New Hampshire Department of Transportation, NH Fish & Game Department, NH Port Authority, NH Coastal Program, City of Portsmouth (NH), Sustainable Portsmouth (nonprofit), Maine Department of Transportation, U.S. Coast Guard, Archer/Western (Canton, MA, large business), Parsons-Brinkerhoff (Manchester, NH, large business), UNH Tech Camp, UNH Infrastructure and Climate Network, UNH Leitzel Center for Mathematics, Science and Engineering Education, and Massachusetts Institute of Technology’s Changing Places (a joint Architecture and Media Laboratory Consortium, in Cambridge, MA).

 

Products                                                                                                                               

Sensors    LivingBridge_Sensors3

Community Involvement                                                                                                      

Memorial Bridge 5K – October 11th, 2014  

  • Temporary Sensor Deployment
  • Informational Handouts
  • Research Team Presence
  • Place-Based Interviews for Pre-project survey

Ocean Discovery Day and Social Media:

•Living Bridge presence on Facebook/Twitter/etc.
•To communicate usable information to the public
        –Use Environmental Sensors (wind, tides, temperature)
        –Use Operational Information (openings)
LivingBridge_OceanDiscoveryDay2  LivingBridge_OceanDiscoveryDay3  LivingBridge_OceanDiscoveryDay1

Interactive informational model on Project website

http://livingbridge.sr.unh.edu/index.php/interactive-bridge-model/

Recent Results:                                                                                                                   

Data Collection June 10th and June 23rd

June 10th: Measured Accelerations at top of main tower, and strains at base of tower

  1. Sheave Support Beam
    •We were able to establish a connection to the receiver from the top of the bridge
  2. Knuckle Connection
    •Instrumentation successful and data collection went smoothly
    •Recorded strain data showed correlation with expected performance
    •Effect of raising and lowering middle span can be felt all along the bridge

June 23rd: Accelerations and strains at middle of south fixed span

  • Problem solving needed for attaching horizontal sensors to curved elements
  • NHDOT supplied crew and equipment to facilitate data collection
  • Experienced a full bridge lift and significant traffic
  • Pending video from bridge of vehicles during data collection

LivingBridge_Clamp       LivingBridge_Tower_Travis       Livingbridge_clampsetup

 

Marine Data:                                                                                                                     

•Piscataqua River tidal current reverses direction ~4 times a day.

        –semi-diurnal tides: in the Great Bay Estuary the M2 tidal constituent dominates.

Tidal energy is a very predictable source of renewable energy, independent of local weather conditions.

•Current velocities and power densities at Memorial Bridge
        –Peak maximum velocities >2 m/s,
        –Average maximum velocities ~ 1.7 m/s,
        –Maximum power density > 2.5 kW/m2
•Power Available:   P = 0.5 ρ U3 A        –Average power density ~ 750 W/m2
•There are three basic parameters here:
        –ρ:  ~ constant
        –U: Current speed : a function of (space, time)
        –A: cross-sectional area (Q: what area to use?)
LivingBridge_MeanPowerDensity

Turbine:                                                                                                                             

LivingBridge_Piscataqua Currents       Tidal Turbine

•This parameter invites several questions concerning what exactly is the value used in the power available estimate.
•The entire cross-section can be used to provide an estimate of naturally available power. But the entire cross-section area is not usable due to:
               -navigation concerns
               -some of it being inter-tidal
               -some of it being just too shallow.
•The area can be further restricted by the cross-sectional area of the power extraction device presented to the flow and what is the spacing at which these
devices can be deployed and be efficient.
•These issues also need to be considered in the context of the spatial distribution of the current speed.

Benefits of utilizing locally available renewable, sustainable, tidal energy at Memorial Bridge:

•Prototype of “estuarine bridge of the future”
•Living laboratory for STEM education
•“Hardens” transportation infrastructure against prolonged grid outages