A Wheeling Suspension Bridge Tour
- by Dr. Emory Kemp
THE WHEELING SUSPENSION BRIDGE TOUR
The history of the Wheeling Suspension Bridge is intimately involved in the history of Wheeling and must be viewed in terms of a national emphasis on what was then called "internal improvements," which meant the construction of a network of transportation systems to join the untapped natural resources of the Midwest with the commercial centers on the eastern seaboard. One of the earliest advocated for "internal improvements" was Albert Gallatin, who as Secretary of the Treasury published his influential report on roads and canals in 1808. However, before the dawn of the nineteenth century Ebenezer Zane, the founder of Wheeling, received approval from the U. S. Congress to build a post road in the Northwest Territory from Wheeling to Limestone (now Maysville), Kentucky. This established Wheeling as a gateway to the Northwest Territories. This position was greatly enhanced with the construction of the National Road from Cumberland, Maryland to Wheeling.
Amid intense debate and bitter rivalries the National Road was approved by the Federal Government in 1806. It took four years to locate the most suitable route and another eight years to complete the construction of this, the first federal road. The first section was opened in 1813 but the road did not reach Wheeling until 1818. In anticipation of the road reaching Wheeling, the Wheeling and Belmont Bridge Company was formed to provide, first by ferries and later bridges, a passage over the Ohio River. The link between Wheeling and the State of Ohio required passage over the main channel of the Ohio River, a roadway across Wheeling Island (earlier Zane's Island) and a passage over the back channel of the Ohio River to the Ohio shore. The entire link was within the State of Virginia because the Ohio border is on the west bank of the river.
Despite the foresight and best intentions of the company the first bridge was not completed until 1836 when a handsome two span covered bridge was completed across the back channel. It was a notable feature on the National Road for many decades and at one time it carried horse drawn street cars. It was replaced in 1893 by the present metal truss bridge complete with decorative iron work.
It was also in 1836 that Charles Ellet, Jr., never one to let an opportunity pass, first confronted the bridge company about the possibility of bridging the man channel and even submitted a sketch of his design of a suspension bridge for their consideration. The seed has been planted, but germination and fruitation took a rather long time.
Ellet's next contact with Wheeling was during the construction of the Fairmount Bridge, in Philadelphia, in 1841. In a visit to Wheeling that year he proposed to build a bridge for $120,000. Ellet's rival bridge builder John Roebling appeared in Wheeling the following year with an alternate design. He estimated his bridge at $150,000, but later revised it to $130,000 to meet Ellet's sum. This was accomplished by eliminating the architectural details.
On March 19, 1847, the General Assembly of Virginia amended the Act of 1816 establishing the Wheeling and Belmont Bridge Co., which authorized the sale of capital stock not to exceed $135,000. The Back Channel Bridge and the easement across the Wheeling Island were incorporated in the new company. In May, the Board of the bridge company invited both Ellet and Roebling to present their designs together with cost estimates. Apparently the bridge company did not issue a brief for the bridge design in sufficient detail to insure that both men were bidding on the same structure. This situation is to be expected in an era before the development of the modern system of producing detailed contract documents including specifications and drawings. After asking Ellet and Roebling to revise their proposals so that a direct comparison could be made for each design the Board appointed Ellet. Recently discovered sketches of Roebling and Ellet for their Wheeling bridge proposals clearly show a marked contrast between Ellet's bold 1000 foot span bridge and Roebling's much more timid design which had the added disadvantage of river piers which would have been difficult to construct, and posed an obstacle to navigation and to the passage of flood water on the Ohio River. From every aspect Ellet's was the superior design. The Board chose wisely.
Later in the same year Ellet, riding on the crest of his successful proposal in Wheeling, was appointed to build the Niagara Suspension Bridge. Thus, he was responsible for constructing two of the world's greatest bridges simultaneously. The sites were separated by three hundred miles of rough roads, which made supervision a challenge to say the least.
To a man interested in his professional advancement and who enjoyed public esteem, the appointment must have seemed to be a dream come true. The dream, however, in part turned into a nightmare with regard to the celebrated Niagara bridge. In the course of construction Ellet exhibited his flare for publicity by sponsoring a kite flying contest to bring the first wire across the gorge. This was followed by the construction of an aerial tramway with an iron basket to give paying passengers the heady experience flying over the gorge suspended by cables only. As an aid in constructing the main bridge a temporary footbridge was built on the suspension principle. Upon its completion Ellet proceeded to ride a horse across the seven foot wide bridge. An amazing feat for the horse when we consider there were no handrails! Although Ellet managed to keep the project in the public's eye he ran headlong into conflict with the bridge company over who should receive the gate receipts from his public entertainment. The upshot of the disagreement was that Ellet was fired and his rival John Roebling was appointed to complete the project. This established Roebling as a leading suspension bridge builder and resulted in his famous double deck Niagara Railroad bridge.
With his project at Niagara eclipsed, Ellet turned his characteristic energy to the construction of the Wheeling Bridge which he completed amid great public acclaim and ceremony, including a procession across the bridge. Ellet had established America's leadership in long span suspension bridge building by completing the world's longest clear span bridge. The leadership was to remain unchallenged in American hands until the 1960s with the completion of major British bridges across the Severn River, the Firth, and Humber River.
THE WHEELING BRIDGE
In 1847, Ellet prepared a report on the suspension bridge to the Wheeling city council. This 43 page report gives not only details of the bridge but also a discussion of the principle of the suspension bridge in terms of the strength of a wire suspended between two points. He demonstrated correctly that an iron wire with a sag of only 100 feet is capable of a clear span of 4,000 feet, four times the length required at Wheeling. He further amplified his argument with a mathematical demonstration of how one can use Navier's classical formulation to calculate the tension in the wire of the main cables. His estimated strength is based upon Chaley's values used at Fribourg in 1834.
The Wheeling Suspension Bridge, as it stands today, has the general appearance of the original bridge constructed in 1849. The massive towers, anchorage housings and island approach are all the original stone masonry. The main cables of the bridge are either original or additions which date from the 1860 reconstruction of the bridge after its collapse in a wind storm in 1854. Its dramatic fall during that storm provided engineers with the best practical lesson in the aerodynamic response of bridges subjected to high winds until the destruction of the Tacoma Narrow Bridge in 1940. The original deck, as shown in Ellet's drawing of 1848, was a simple timber deck resting on transverse timber floor beams which were in turn supported at their ends by wrought iron suspenders hung from the main cables.
The present stiffening truss is a classical Howe timber truss with cast iron joint fittings and wrought iron vertical tension rods, which probably date from the 1860 reconstruction.
The auxiliary stay cables were added at the time of the 1871-72 strengthening to a design by Washington Roebling. This effectively "Roeblingized" the appearance of the bridge suspension system although the main cables and the vertical suspenders were unaltered. Washington Roebling and Wilhelm Hildenbrand also widened the cables to enable the walkways to be placed inside the stringers, thus improving the appearance and the lateral stiffness of the bridge.
Changes in the deck made in 1922, 1930 and 1948 were largely superceded by rebuilding of the deck in 1956. At that time the roadway was widened to 20 feet from 16 feet 3 inches, while the sidewalks were correspondingly narrowed. The entire deck constructed in steel with an open steel grating for both the walkway and roadway which rests on steel floor beams, was used in order to cut down on the dead loads and the wind resistance.
In the Wheeling City Directory of 1851 the original bridge was described:
The span is 1010 feet from the summit of tower to tower, leaving the entire width of the river unobstructed.
The summits of the towers on the eastern, or Wheeling shore, are 153 1/2 feet above low water level of the river. Their actual height from the base of the stone work is 82 feet; abutment 22 feet, towers 60 feet.
The western towers, on Zane's Island, are 132 3/4 feet; the abutment is 63 feet, and the columns of the towers 69 3/4 feet.
The summits of the eastern towers are 21 3/4 feet above the western towers.
The flooring is supported by twelve iron cables suspended from the towers, 10 large and 2 small ones. The large ones contain 550 strands of number ten wire, and the small ones 140 strands.
The cables are anchored by a succession of links, like those of a huge chain, into massive walls of masonry built under Main Street in Wheeling. Those at the west end are anchored in like manner in the wing walls extending from the abutment on the Island.
The cables are 1380 feet long from fastening to fastening. Their deflection below the top of the eastern tower is 68 1/2 feet at a temperature of 44 degrees.
The flooring is attached to the cables by wire stays 3/4 of an inch in diameter, (i.e., vertical suspender rods 3/4" diameter) varying in length as they approach and recede from the towers.The highest elevation of the flooring is immediately over the channel of the river, 212 feet from the Wheeling shore, where the top of the flooring is a fraction over 93 feet above low water. The height from low water to the bottom of the flooring, i. e., the lowest projecting timber, is 91 1/2 feet, leaving that space, subject to the fluctuations in the depth of the channel, for the passage of steamboats and other vessels beneath.
The flooring ascends from the Wheeling side for 172 1/2 feet at the rate of 1 28/100 feet in 100; thence it ascents forty feet more at the rate of 525/1000 feet in 100; thence it descends for forty feet at the rate of 925/1000 feet in 100, and then descends to the western abutment at the rate of 4 08/100 in 100.
On top of the towers the cables rest on cast iron rollers which adapt themselves to any movements of the cables occasioned by changes of temperature or transitory loads.
The strength of the bridge, as computed by Mr. Ellet, is sufficient to resist 297 tons, or 32 heavily laden road wagons, 192 horses and 500 people, a weight equal to an army of 4,000 men -- greater probable weight than it will ever be required to sustain.
To protect the oldest major long span suspension bridge in the world, the West Virginia Department of Highways spent $2.4 million in 1982 to repair the cables and anchorages, rebuild the trusses and repair the bridge. On May 5, 1983 the people of West Virginia celebrated the grand opening of the restored Wheeling Suspension Bridge. The bridge was lighted in 1987. The most important pre-Civil War engineering structure in North America has been saved.
The Wheeling Suspension Bridge was honored as a National Historic Civil Engineering landmark in 1969, and in 1980 the bridge was listed on the National Register of Historic Places of the United States Department of the Interior. In 1975 the Wheeling Suspension Bridge received the highest honor that can be bestowed on a non-federal site or structure when it became the first bridge to be designated a Nation Historic Landmark. The bridge is currently being nominated as an international landmark by the International Council on Monuments and Sites.
STATION 1. — ANCHORAGES
The National Road descends from Wheeling Hill, passes along Main Street to 10th Street where it turns sharply and crosses the Ohio River on the Wheeling Suspension Bridge. Underneath the intersection of the 10th and Market Streets lies the massive anchorage for the eastern end of the suspension bridge. These anchorages consist of large wrought iron eye-bars linked together to form a chain. These chains are embedded in a brick vault which covers nearly the entire intersection of 10th and Market Streets. The end of the chain emerges in the anchorage vaults. The ends of each of the original twelve cables are fastened to the end of the eye-bar chain by clevises. In addition to the original cable anchorages, the secondary stay cables are also anchored in this vault. These were installed during the 1871-72 bridge strengthening. All of these cable connections to the anchorage chains can be seen by peering through the grillages on the anchorage vaults.
STATION 2. — TOWERS AND SADDLES
The towers are constructed in a simple unadorned style consisting of a single semicircular arch opening for the roadway surmounted by two short towers providing support for the saddles. The saddles are composed of a simple system of one large roller flanked by two smaller rollers. As the wire cables passed over the saddles they were flattened out to prevent excessive local stresses on the bottom wires of the round cable. As a protection again corrosion, the saddles are covered in grease which is in turn capped with a sheet metal covering and finial. Careful inspection of the rollers indicates that they have not functioned for many years, perhaps not since the cables were first installed. Thus, any lengthening or shortening of the main cables occurs between the towers and results in the rise and fall of the deck of some four or five inches between maximum and minimum loadings. The sandstone towers are still covered with soot giving clear evidence of the heavy air pollution in 19th century Wheeling. Looking up at the towers on the downstream side, one can see where the top stone course adjacent to the saddles has been broken in two places on each tower. It is believed this is where the cables landed when they were thrown off the saddles in the windstorm of 1854. The simple design of the towers probably resulted as an economy measure since they follow neither the Arc de Triomphe design originated by William Tierney Clarke and favored by the French, nor the Egyptian revival style used by Brunel and Roebling in their bridges.
STATION 3. — STIFFENING TRUSSES
The original design by Ellet was a simple unstiffened wooden deck the details of which were taken directly from Navier's famous report on suspension bridges published in 1823. In order to stiffen the deck against excessive deflections caused by wind or live load, Howe trusses were used in 1860. The Howe truss was patented in America in 1840 and provided a quick and simple method of building a stiffening truss using timber members, cast iron junction boxes, and wrought iron vertical tension members. Thus the truss could be quickly erected using only semi-skilled labor. It also provided the added advantage that individual members could be replaced by unscrewing the vertical tension members. It should be pointed out that the French developed this type of truss long before Howe secured his American patent and indeed the earliest French suspension bridges by Seguin featured this kind of truss. Changes were made in the deck in 1922, 1930 and 1948. None of the original timber survives and only a few of the original timber survives and only a few of the iron fittings date from the 19th century. Nevertheless, the truss is of the same configuration as the original.
STATION 4. — DECK
The present deck consists of an open grid steel deck supported on transverse steel floor beams. These, in turn, are connected to the vertical suspenders. This deck was installed in 1956 to replace an earlier series of timber decks. This deck was retained in the 1983 bridge renovation. Although not representative of the original design, its principal advantage is any tendency for the deck to twist under transverse wind loading will be minimized because the wind can pass through the steel grid, greatly reducing the lateral pressure on the deck. In order to provide easy grades onto and off the bridge, the towers were located at different elevations. In addition, since the main channel of the river passes along the Wheeling shore, and a minimum of 90 feet clearance at high water was required, the bridge rises gently to clear the main channel and then descends on a straight line to the western tower and approach structure.
STATION 5. — CABLES
Since the cables pass down to the level of the deck at mid-span, it is possible at this location to examine their construction a close hand. The original cables consisted of 6 individual garland designed cables, reminiscent of the French tradition pioneered by Seguin. In order to stiffen the cables, the six cables were grouped into one pair on each side of the bridge during the 1860 reconstruction. These four new cables consisted of individual wires in a matrix of linseed oil and then the entire cable covered with apast of red lead to prevent corrosion. The cable was wrapped with small diameter soft iron wire wrapped continuously from anchorage to anchorage. This is turn was painted with red lead as a primer and then painted with an exterior, lead-based paint. Examination of the cables during the 1983 reconstruction indicated that the main longitudinal wires, with one or two exceptions, were found to be in remarkable good condition, indicating that the original system was an excellent design. Nevertheless, it was decided to rewrap the cables with a modern, elastomeric plastic covering over the original wire cables. Because the elastomeric wrap was too soft to receive the suspender clamps,wire was wrapped around the cable at each suspender location and the wrapping installed after the suspenders and clamps were fitted. Many of the suspenders are the original wrought iron suspenders dating from the 1860 reconstruction,however a number of them have been replaced with modern clamps and steel suspender rods. In 1871-72, the bridge was strengthened by Washington Roebling and Wilhelm Hildenbrand of the Roebling Company. The primary feature of this strengthening was the installation of a series of stay cables radiating from the towers and connecting into the floor beams of the deck. This strengthened and stiffened the deck and effectively "Roeblingized" the appearance of the bridge. It is this 1871-72 strengthening by the Roebling Company which gave rise to the legend that John Roebling rebuilt the bridge totally after it collapsed in the wind storm of 1854.
STATION 6. — A CONFLUENCE OF TRANSPORTATION SYSTEMS
From the middle of the bridge is possible to see the National Road coming down Wheeling Hill from the east and approaching the bridge along Main Street. Just upstream from the bridge at approximately the location of the modern Fort Henry Bridge, was the limit of navigation on the Ohio during low water in the summertime. Looking downstream near the modern steel parking garage, one can see where the flourishing steamboat trade loaded and unloaded cargo at the port of Wheeling. Beyond the parking garage is the new Wheeling Civic Center which is on the side of the original terminus of the mainstem of the Baltimore and Ohio Railroad. On this site was located the classical revival passenger station and the notable freight station and freight shed supported by a series of 90-foot span think trusses. Thus Wheeling was the confluence of three important national transportation systems.
STATION 7. — WESTERN TOWER AND ABUTMENT
Because of the availability of space on Wheeling Island the cable anchorages and approach structure were combined into an impressive sandstone structure which connected the towers and the anchorage vaults. Unlike the eastern anchorages, the later stay cables were anchored one at a time in the pilasters of the stone masonry between the anchorages and towers. From the western anchorages the road passes across Wheeling Island and crossed the back channel on a multi span wooden covered bridge which was replaced in 1893 by a notable iron truss bridge produced by the Wrought Iron Bridge Company of Ohio.