Mighty Mac: Bridging the Mackinac Straits

Mighty Mac: Bridging the Mackinac Straits

J.M. Syken

Course Outline

In this course, we will examine the historical background, political, economic and technical challenges culminating in the construction of one of the world’s greatest bridges. The early efforts, starting in the 1880s, to build a bridge across the five-mile wide Straits of Mackinac separating the upper and lower peninsulas of Michigan and linking Lake Huron with Lake Michigan will be discussed in-depth and detail as will be the plans to construct a bridge in the years immediately before and after WWII. The need to alleviate the chronic traffic backups, especially in the peak fall season, and the role of ferry boats plying the Straits and their inherent limitations will also be included in this discussion as will be the role of Prentiss M. Brown: “The Father of the Mackinac Bridge.”

The genesis and detailed design of the sub and superstructure of the bridge to resist the considerable ice pressures and dynamic (wind) forces in the Straits, as conceived by the great bridge engineer Dr. David B. Steinman, will be discussed at length. The background of his long and distinguished career as a bridge engineer/builder will also be highlighted. The mighty task of constructing the bridge over four relatively short construction seasons, starting in 1954 and culminating with the opening of the bridge on November 1st 1957, will be a subject of great interest. The legacy of the bridge and its on-going importance to lives of the people of Michigan will conclude the presentation.

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will:

Understand/appreciate the historical background of the Straits of Mackinac starting in the French colonial period;
Understand/appreciate the unique geological and climatic conditions present in the Straits;
Understand/appreciate the development of the area of the Straits and the upper peninsula as a vacationland;
Understand/appreciate the call for a bridge across the Straits in the aftermath of the completion of the Brooklyn Bridge across the East River in 1883;
Understand/appreciate the role of ferry boat service in the Straits and their limitations;
Understand/appreciate the role of future U.S. Senator from Michigan Prentiss M. Brown as a life-long resident of St. Ignace and his determination to have a bridge built across the Straits based on his personal experiences;
Understand/appreciate the significant developments and momentum to build a bridge across the Straits starting in the mid-1930s to the outbreak of WWII;
Understand/appreciate the importance of the preliminary report to the Mackinac Bridge Authority (MBA) prepared by three prominent bridge engineers;
Understand/appreciate the role of Dr. D.B. Steinman in the development of a design for a bridge across the Straits which would be capable of resisting all the natural forces imposed by the Straits geology and climate;
Understand/appreciate the logistics, mobilization and construction efforts of Merritt, Chapman & Scott in the difficult and challenging task of creating thirty-three bridge foundations/piers;
Understand/appreciate the role of the United States Steel Company and their American Bridge Division in fabricating and erecting the bridge’s superstructure and the aerial spinning of the wire cables; and
Understand/appreciate the political, cultural and economic impact/s and legacy of the bridge which provides the physical link between the geographically divided State of Michigan.

Intended Audience

This course is intended for architects, engineers and other design professionals.

Benefit to Attendees

The attendee/s will gain an intimate knowledge and insight into the creation of one of the greatest bridges in the world and the crowning achievement of its creator: renowned bridge engineer Dr. David B. Steinman.

Course Introduction

The course includes an in-depth PowerPoint presentation and the viewing short documentary films.

Course Content

In this course, you are required to view/study the following slideshow and the materials contained in the web pages:

Mighty Mac: Bridging the Mackinac Straits (printable handout in PDF, 9 MB, see Note A below for downloading instruction)
Mighty Mac: Bridging the Mackinac Straits (non-printable slideshow for screen-viewing only, 44 MB, see Note A below for downloading instruction)

Archival/Documentary Film:

TITLE: The Five-Mile Dream (1958)
LINK: http://archive.org/details/0388_Five_Mile_Dream_The_M04236_20_21_10_00
DURATION: 09:42

TITLE: Building the Mighty Mac
LINK: https://www.youtube.com/watch?v=C07hGxEij3M
DURATION: 55:03

Note A: Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right-clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader from your computer.

Course Summary

In ancient Rome, the Pontifex (Bridge-Builder) was held in very high regard by Roman Society. After all, it was her roads and bridges that made Rome an interconnected empire. Jealous of their popularity, the Roman emperors took on a title for themselves: Pontifex Maximus (Great Bridge Builder). Even today, the title of the Pope: Pontif, recognizes the high regard human society retains for its bridge builders. The story of the Mackinac Bridge is the story of a modern-day Pontifex – Dr. David B. Steinman and, in this case, the citizens of Rome are replaced with the grateful citizens of the State of Michigan. The bridge Dr. Steinman conceived in his fertile imagination and brilliant analytical mind would hold the forces of nature at bay and provide the physical link necessary to make Michigan a whole rather than two halves. The courage and sacrifice of the men who built it is the stuff of legend while the bridge itself serves as a utilitarian edifice for trans-Straits commerce/transportation. Bridging the wide and difficult Mackinac Straits is a case-study of how and why bridges mean so much to the lives of a vital civilization and why D.B. Steinman rightfully earned the title: “Pontifex Maximus.”

Related Links

For additional technical information related to this subject, please visit the following websites:

http://en.wikipedia.org/wiki/Mackinac_Bridge

http://en.wikipedia.org/wiki/David_B._Steinman

https://www.youtube.com/watch?v=FuWM6-xOQCY
(Film: The world's Longest Bridges - 08:50)

https://www.youtube.com/watch?v=c8-DyNIezmM
(Film: Drain the Great Lakes of America - Secrets of the Freshwater Oceans- 45:11)

https://www.youtube.com/watch?v=g0WSPkdf1OE
(Film: World's Most Extreme Bridges - 52:06)

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.