The University of Toledo The University of Toledo Digital Repository Theses and Dissertations 2013 Ice prevention or removal of Veteran's Glass City Skyway cables SeyedAli ArbabzadeganHashemi The University of Toledo Follow this and additional works at: http://utdr.edu/theses-dissertations Recommended Citation ArbabzadeganHashemi, SeyedAli, "Ice prevention or removal of Veteran's Glass City Skyway cables" (2013). Theses and Dissertations. This Thesis is brought to you for free and open access by The University of Toledo Digital Repository. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of The University of Toledo Digital Repository.
For more information, please see the repository's About page. A Thesis entitled Ice Prevention or Removal of Veteran’s Glass City Skyway Cables by SeyedAli ArbabzadeganHashemi Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Civil Engineering _________________________________________ Dr. Nims, Committee Chair _________________________________________ Dr. Gruden, Committee Member _________________________________________ Dr.
Terry Ng, Committee Member _________________________________________ Dr. Hunt, Committee Member _________________________________________ Dr. Komuniecki, Dean College of Graduate Studies The University of Toledo December 2013 Copyright 2013, SeyedAli ArbabzadeganHashemi This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author.
An Abstract of Ice Prevention or Removal of the Veteran’s Glass City Skyway Cables by SeyedAli ArbabzadeganHashemi Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Civil Engineering The University of Toledo December 2013 The Veteran’s Glass City Skyway (VGCS) is a large cable stayed bridge with single pylon crossing over Maumee River in Toledo, Ohio. This structure was put into service in the summer of 2007 and carries three lanes of traffic in each direction. Under some weather conditions, ice forms on the stays of VGCS. Ice accumulation can exceed one half inch and accumulated ice may persist on the stays for several days.
As the stays warm, ice falls from stays and posing a potential a hazard for motorists and requiring lane closures. Lane closure cause inconvenience to public travelling and economic losses. To assist the Ohio Department of Transportation in developing ice hazard mitigation strategies and providing information to assist ODOT in managing the VGCS during icing events, several studies have been carried out. This thesis will address four aspects of ice hazard mitigation on the VGCS.
1) Icing experiment station which was designed, built, and successfully operated 2) Outdoor experiments on the full scale specimens 3) Report the test results 4) Selection of sensors to obtain required information iii 5) Design of the anchorage for self-supporting tower. To help the Ohio Department of Transportation, a study which includes an analysis, assessment, and preliminary validation tests of the most viable technologies for anti-icing/deicing of the VGCS stays has been performed. Information for developing an anti-icing/deicing strategy was gathered during outdoor experiments on the full scale sheath specimens. Sensors which give a better understanding of the microclimate of the VGCS before, during, and after of icing events were chosen.
A self-supporting instrumentation tower was selected and installed on the median of the VGCS to gather data from sensors, and improve the performance of the dashboard. Typical double-nut anchorage system based on AASHTO sign specification was designed to support the instrumentation tower on the median of the VGCS. iv Acknowledgements I take this opportunity to express my thanks and acknowledge to my advisor Dr. Nims for his encouragement and continuous support during my master study.
I would like to thank Dr. Ng for his support and directions during my research. I also would like to thank Dr. Gruden and Dr.
Hunt for being on my committee. I thank University of Toledo students Mr. Owjan Hashtroodi, Mr. Hamed Ghaedi, and Mr.
Nutthavit Likitkumchorn for their assistance in setting up the Scott Park Campus icing experiments. I also would like to thank University of Cincinnati graduate students Mr. Jason Kumpf and Mr. Biswarup Deb for their efforts in development of dashboard and installation of bridge sensors.
This project was sponsored by the Ohio Department of Transportation. The author gratefully acknowledges their financial support for both this study and also installation of instrumentation tower. The author also would like to thank ODOT personnel Mr. James Bradley and Mike Gramza for their support in tower design and overall supervising during this project.
vi List of Tables. viii List of Figures. ix List of Abbreviations .1 Statement of the Problem .2 Bridge General Information .1 History of Icing Events on the VGCS.2 Lessons Learned from the past Icing Events .5 Most Viable Technologies for VGCS. 25 vi 3 Managing Icing Events .2 Ice Fall Dashboard .4 Self-Supporting Instrumentation Tower.2 Anchorage System Design.
43 4 Outdoor Experiments on the Full Scale Specimens .1 Data Acquisition System and Sensors .2 Icing Simulation Experiments. 55 5 Conclusion and Future Work. 62 A Anchorage Design Calculations. 82 vii List of Tables 2.1 Ice Accumulation Weather Condition……………………………………….2 Ice Falling Weather Conditions…………………………………………….3 Most Viable Solution…… …………………………………………………………25 3.1 Ice Accumulation and Ice Shedding Criteria……………………………….2 Uncertainties that Need to be Resolved…………………………………….3 List of Thermistors Abbreviations………………………………………………….34 viii List of Figures 1-1 Ice Accumulation on the East Side of the VGCS…………………………………….2 1-2 Ice on the Pylon and the VGCS Glass.
3 1-3 Large Piece of Almost Ice Hitting a Car. 3 1-4 Veteran’s Glass City Skyway. 4 1-5 Schematic of Stay Cable Cross-Section. 5 2-1 Ice Accumulation Pattern, Febrarury 20th , 2011.
11 2-2 Ice Accumulation Patten, February 23rd, 2011. 12 2-3 Weather Summary for the Week of 2011 Icing Event. 13 2-4 Solar Radiation, February 24th, 2011. 14 2-5 Application of Hydrophobic Coating on the Surface.
16 2-6 DC Bias Deicing where Electrolysis forms Bubbles. 17 2-7 Pulse Electro Thermal Deicing (PETD). 18 2-8 Ice Being released using Dielectric Heating. 19 2-9 Navy Vertical Launch Systems with Electrically Heated Door Edges.
20 2-10 Infrared heaters above CRREL Entrance. 21 2-11 Aviation Facility using Infrared Radiant System. 22 2-12 Photonic deicer for deicing of power lines. 27 ix 3-2 Dashboard Readout for February 21, 2011.
28 3-3 Goodrich Ice Detector. 31 3-4 Leaf Wetness Sensor. 32 3-5 Location of Thermistors on VGCS (Stay 8 and 20). 33 3-6 Themistors on the VGCS.
33 3-7 Crack on the Ice Layer with Liquid Water. 35 3-9 Stay Temperature – 16th to 17th of January 2013. 36 3-10 Stay Temperature – 2013 Minor Icing Event. 37 3-11 Stay Temperature – 15th to 16th of May 2012.
39 3-13 Campbell Scientific Rain Gage. 39 3-14 Installation of Rohn Tower on Median of the VGCS. 40 3-15 Tower Anchorage System. 43 4-1 Google Earth Shot of Scott park.
45 4-3 Sensors on South-faced Specimen. 46 4-4 Data Acquistion System. 47 4-5 Spraying a Mist of water on North-faced Specimen. 48 4-6 Pattern of Ice Accumulation on Outdoor Tests.
48 4-7 Water Beneath the Ice Layer before Shedding. 49 4-8 Ice Shedding Steps. 50 4-9 Stay’s Behaviour in Icing Test – 2/15 to 2/18. 51 x 4-10 Stay’s Behavior in Icing Test – 2/20 to 2/22.
52 4-11 Formation of Ice in Chemical Anti-icing Test. 54 4-12 Drip Tube System used in Chemical Deicing Test. 55 4-13 Hydrobead Sprayed on the half of Specimen. 56 4-14 Water Droplets due to Hydrobead.
56 4-15 Specimen’s Behavior in Coating Test. 57 xi List of Abbreviations AASHTO……………American Association of State Highway and Transportation Officials ACI………………….American Concrete Institute AISC……………….American Institute of Steel Construction ASD…………………Allowable Stress Design CRREL………………Cold Region Research Laboratory EEDS……………….Electro-expulsive Deicing Systems HDPE .High Density Polyethylene LRFD……………….Load and Resistance Factor Design LWS…………………Leaf Wetness Sensor ODOT .Ohio Department of Transportation PETD.Pulse Electro Thermal Deicing RWIS……………….Roadway Information System TEO…………………Thermistor East Outer TES…………………Thermistor East Sheath TLS………………….Thermistor Lower Sheath TUO…………………Thermistor Upper Outer TUS…………………Thermistor Upper Sheath TWS……………….Thermistor West Sheath VGCS .Veteran’s Glass City Skyway xii Chapter 1 Introduction 1.1 Statement of the Problem The Veteran’s Glass City Skyway is a large cable-stayed bridge with a single pylon crossing over Maumee River in Toledo, Ohio. The VGCS is owned by Ohio Department of Transportation and is considered as the most expensive project ever undertaken by ODOT (Wikipedia, 2013). Under some winter conditions, ice forms on the stay cables of VGCS.
Ice accumulation can exceed one half inch and accumulated ice may persist for several days on the stays. As the stays warm, ice sheds from the stays in cylindrical sheets. The sheets may fall over 250 feet to the roadway and can be blown across several lanes of traffic. Ice sheds from the stays in less than a minute.
The potential of falling sheets requires lane closure for the duration of the ice persistence. The VGCS, which is an important connector for multimodal transportation and economic development, has thousands of vehicles crossing daily. Lane closures cause inconvenience to traveling public and loss to economic activities. Falling ice is a safety hazard to motorist and determining ice 1 presence remotely is problematic.
Determining ice presence manually puts ODOT personnel in harm’s way. At this time, there is no existing anti-icing/deicing technology that appears to be practical for mitigating the icing problem on the VGCS. This means the solution may be a combination of existing technologies or completely a new approach. The Ohio Department of Transportation has contracted The University of Toledo to design and develop a viable anti-icing/deicing solution for VGCS icing problem.
This study is the phase two of an extended icing contract with Ohio Department of Transportation. Figures 1-1 and 1-2 show ice accumulation on the stays and pylon of VGCS in the 2011 icing event. Figure 1-1: Ice Accumulation on the East Side of VGCS 2 Figure 1-2: Ice on the Pylon and the VGCS Glass Figure 1-3, which was captured during 2011 ice fall event, shows a large piece of ice falling into the third lane of traffic while vehicles are still crossing over the bridge. Red circle shows a piece of ice which nearly hit a car (Belknap, 2011).
Figure 1-3: Large Piece of Ice Almost Hitting a Car (Belknap, 2011) 3 1.2 Bridge General Information Veteran’s Glass City Skyway, previously known as the Maumee River Crossing, is a large cable stayed bridge crossing over Maumee River on Interstate 280 in Toledo, Ohio. The VGCS is one of two installations of a new cradle system which eliminates the anchorage system on the pylon by carrying the stays from one side of the bridge deck to another side. The construction of this structure began in 2001 and the bridge was put into service in the summer of 2007. VGCS carries three lanes of traffic in each direction.
The entire project consists of 8,800 feet of approaches and main span. The main span is cable- stayed type bridge with a single pylon of approximately 216 feet above the bridge deck and two approaches on each side. The north bound approach is approximately 4,000 feet and south bound approach is approximately 3,350 feet. Figure 1-4 shows VGCS’s main span on Maumee River and part of the approaches.
Figure 1-4: Veteran's Glass City Skyway 4 1.3 Stay Description The VGCS stays consist of a sheath and epoxy coated strands. The sheaths are made of 316L stainless steel. The VGCS stays have 82 to 156 strands depending on their location. The outer diameter of the stays is either 18” or 20” depending on number of strands inside of them.
The thickness of the sheath is 1/8”. The stay sheaths of the VGCS serve no structural function. They cover and protect the epoxy coated prestressing strands. Brushed stainless steel was chosen for its low life cycle cost and aesthetic qualities rather than conventional high density polyethylene (HDPE).
Figure 1-5 shows a schematic of the sheath resting on the epoxy coated strands at mid-height of a long stay.