The Public "I": LINKS IN A CHAIN

Friday, December 30, 2016

LINKS IN A CHAIN

I can tell you the very moment the chain was broken. At 4:55 p.m., Howard and Marjorie Boggs were returning from a Christmas shopping trip to the river side town of Gallipolis, Ohio. Marjorie, who was just 18, was driving. And as they crossed the half mile wide Ohio River, bound for Point Pleasant, West Virginia, Howard remembered “the old bridge began to gently bounce, as always” - as it had done every day for the last forty years. But on this December day, perhaps it felt different. Perhaps Marjorie was more sensitives because her 15 month old child was also in the car. Whatever the cause, Marjorie turned to her husband Howard and asked, “What would we do if this thing were to break up?”.

Since the middle of the twentieth century, West Virginia has had only two exports: coal and people. The old joke said “The Mountaineer State" school children studied their three “R's” - reading, 'righting and route 35. Over the decade of the 1950's one in four residents - almost half a million people- took the “Hillbilly Highway” north, looking for work and new homes.

And the choke point for most of this coal miner diaspora occurred 265 miles downstream from Pittsburgh, at a single two lane link just upstream of the mouth of Kanawha River and just downstream from a C.and O. railroad bridge, between the tiny villages of Point Pleasant, West Virginia and Gallipolis, Ohio (above).

The design was put out for bids in 1926 by West Virginia. It called for three separate bridges, tied together. Beginning in downtown Point Pleasant, the two lane, 22 foot wide roadbed crossed a standard 380 foot truss bridge to the southern pier in the Ohio River. For the next 700 feet, the road would be suspended by twisted steel cables hanging between two 510 foot towers. From the northern pier a second truss bridge carried the road 380 feet to the Ohio shore, and a 400 foot approach ramp. But the primary subcontractor for the winning bid, had a couple of suggestions.

First, the American Bridge Company wanted to raise the northern pier by eight feet, to give the roadbed 102 feet of clearance over the barges that used the river. And secondly, they suggested replacing the steel cables with a new technology – 45 to 55 foot long bone-shaped heat treated steel I-bars, joined into chains. I-bar chains had a century of use behind them, but this would be the first time the new heat treated steel bars with a maximum working stress of 50,000 pounds per square inch, would be used in America.

Eyelets drilled at the ends of each I-bar allowed an 11” diameter steel bolt, washer and nut to lock adjoining bars into a chain, or into a sealed triangular junction which transferred the horizontal load of the roadbed to the vertical towers. The stronger steal would require just a single I-bar on each side of the chain, and the “give” designed into the joints allowed the load to be transferred as traffic moved across the structure. Because they were forged off site and were quickly assembled on site, construction cost was just $825 thousand, and was completed in just six months. The new bridge, painted silver, opened on Memorial Day, 1928 A rain storm failed to dampen the inaugural day spirits. As the “The Engineering News Record” crowed, the Silver Bridge would last 100 years.

It was later estimated the new bridge added $1 million a month to the local economy, the traffic growing to 4,000 vehicle crossings a day, 340 cars and trucks every hour. But built to spur the economy of West Virginia, it instead become a link in an immigration chain that ran north from Charleston to Point Pleasant, and then Columbus or Cincinnati, Ohio, and the steel belt beyond - St. Louis, Chicago, Detroit, Cleveland and Pittsburgh.

During the 1960's the population of West Virginia fell by another quarter of a million, an exodus of another 44 people every day heading north. The joke now went, St. Peter was giving a tour to a new arrival in heaven. When asked about a section surrounded by a wall, he explained, “Oh, that's where we put the West Virginians. Otherwise they all try to go back home on the weekends.” And each year, between Thanksgiving and New Years, the back splash of homesick exiles became a tidal wave, filling the country roads with nostalgic melancholy expatriates returning home to West Virginia.

As with any chain, there were weak links. The Point Pleasant (above) approach terminated at a traffic light at the corner of Sixth and Main streets. Every red light cycle backed up traffic onto the bridge. Another traffic light on the Ohio side added to the load, and the redundancy was further stretched by progress.

In 1928 (above), the average fully loaded truck weighed 5,500 pounds, or 2 ¼ tons. Thirty years later the weight of a tractor-trailer was up to 60,000 pounds, or 30 tons. By 1967 such trucks were 20% of the traffic crossing the Silver Bridge, and rush hour, particularly during the holiday season, had extended until it lasted all day long. The bridge seemed to deal with this increased load easily, in part because, as was noted by “The Engineering News Record” back in 1928, it was not possible to examine the underlying I-bar in the triangular joints, nor was it possible to make “any adjustments in the chains...after erection.”

The state gave the Silver Bridge a “full inspection” on 8 and 9 April, 1965, and $30,000 was spent on repairs to the roadway, replacing peeling paint, and patching some erosion on the chain anchorages. But inspector Paul McDowell admitted later he completed only 11 of the 21 standard checks. Lack of funding prevented him doing a full, eyes on, examination of the links before using his “engineering judgment”, to declare the bridge “structurally safe”. When the bridge was checked again on 6 December 1967, the maintenance engineer used binoculars to check the I-bar chain links, and saw nothing of concern. Ten days later, just after 4:50 on the cold Friday afternoon of 16 December, 1967, Lloyd Forge, a semiretired welder from Point Pleasant, was crossing the bridge when he spotted a large steel nut lying in the road bed near the Ohio shore. It was, according to all reports, the first evidence of any failure to any structural part of the bridge. And it was already too late to do anything about it.

Five minutes later, at the intersection of Ohio Route 7 and U.S. route 35 (above), a hundred feet north from the Ohio approach ramp, Mr. H.L. Whobrey was loading the evening's first sale from his Christmas tree lot into the trunk of a customer's car, when he heard what sounded like an auto crash on the bridge. To gas station owner Dick Kuhn, working on the south side of the same intersection, it echoed like a shotgun blast fired from under the bridge. Other witnesses heard a jet -like roar., or a clanging noise. Bank employee, Roger Wysell was eastbound on Route 7, and had just pulled up to the traffic light at the intersection with Route 35, between Whobrey and Kuhn, when his passenger, Cathy Zuspan, screamed, “My God the bridge is falling.”.

A half mile south, Bob Rimmey was parked in front of the Point Pleasant court house, a block from the bridge, when he head a loud crack. He could see nothing from where he sat, so he stepped out of his car. In the distance he saw the Silver Bridge swaying, and watched one tower after the other fall, then saw the roadway pitch over to one side and collapse into the 42 degree water. It took less than a minute before it was over. He ran toward the bridge.

Looking up from the tree he had just loaded, Mr. Whobrey saw “the bridge just keel over, starting slowly on the Ohio side, then following like a deck of cards to the West Virginia side...I saw it but I didn't believe it” The last car to clear the collapsing bridge pulled into Whobrey's parking lot and screeched to a stop. Whobrey noted the driver “...looked like a ghost. He just sat there - then he was sick right in the car.” Station owner Kuhn ran to the riverbank and watched a truck floating south with the current. "There was a guy hanging onto the roof yelling his head off. I think they got him off.” There were now, just seven minutes of daylight left.

A half mile away, 20 year old Charlene Wood was heading home from her job at a hair salon. She was 5 months pregnant and had just driven her yellow Pontiac through the traffic light at Main and Sixth streets in Point Pleasant. “I was traveling in the right lane about 15 miles an hour when this car in front of me started going in...I felt a shaking of the bridge...I threw my car in reverse. The shaking was so severe my car died, but it kept rolling back because of the incline. As I was watching in horror, the bridge was falling right in front of my eyes. It was like someone had lined up dominoes in a row, and gave them a push, and they all came falling down and there was a great big splash of water. I could see car lights flashing as they were tumbling into the water. The car in front of me went in. Then there was silence”

A few seconds later Bob Rimmy and a West Virginia State Police officer reached the yellow Pontiac just four feet from the broken end of the roadway. Charlene Wood's hands were frozen on the steering wheel, and she did not respond to their shouts. Rimmy and the officer helped Charlene out of her car and back to safety. Four months later she would give birth to twins.

Young Howard Boggs did not remember the fall, or escaping from the car. He did recall feeling the river bottom , thirty feet down, under his feet . When a Gallopolis ice and fuel boat pulled him from the cold water, he told his rescuer, “I just hope to God Marjorie and the kid got out okay.” His wife and baby were pulled out of the river, still inside their crushed car, six weeks later.

Volunteer fireman Lee Long responded to the call and found a scene of confusion. “It was a hell of a mess”, he told a reporter. “I saw this car float past. It looked like there were people inside beating their hands on the windows....We couldn't see very much, but we could sure hear it."

"There was a tractor-trailer rig hanging on the riverbank, partly in the water. The driver was hanging from the open door of the cab, dead. Then we heard this banging from the back...it was the driver's partner who'd been sleeping...We worked two hours to cut him out of there...Standing there naked except for his shorts...Man, was he shivering. Then he saw his partner, and he just broke up.”

Sixty-four people in 31 vehicles were dropped into the river or on the Ohio approach.. Forty-four of them died, most by drowning or from severe trauma.

Two of the dead were lost to the Ohio River. Eighteen others survived.

It was later decided that the break began with a speck of impurity in the steel of one particular I-bar, labeled as C-31, used to form the second link in the western chain from the top of the north tower. Hidden beneath a locking nut, it took forty years of heat and cold, tension and release, to expand to one tenth of an inch in length.

At that instant, it went critical, snapping through the lower side of the eye-let. The I-bar shifted outward the next time it flexed. That threw the locking nut onto the roadway, and left the entire load of the bridge, the steel, the roadbed, the traffic, the human beings, a 15 month old baby, balanced on half of an unhinged I-bar. It could not carry the load and gave way.

That transferred the entire load to the opposing chain link, which gave way. Like the collapsing floors in the World Trade Center on 9/11, each successive member of the bridge was now asked to carry even more weight than the failed member before it. Each link thus failed in their turn more quickly, until the entire structure of the bridge fell in less than sixty seconds.

The engineering lesson was, as it had been before and will be again, that redundancy must be designed into entire structure, not merely in the individual members of those structures. .