Friday, May 24, 2013

The Bomb Shelter

Part One

In 1961, President Kennedy came from a meeting in Vienna with Chairman Khrushchev of the Soviet Union aware that our two nations faced a potential nuclear war. After his return here, he advised us all that we should consider building fallout shelters. I had doubts that our two nations would engage in mutual destruction so soon after a world war only 15 years past. My father had no interest in building such a shelter, and said that he and my mother doubted that they would want to live in whatever world remained from such a war. However, the newspapers and magazines were full of speculation about the need for these structures and of articles describing how to build them. It was generally agreed that one could not build them strong enough to survive blast destruction; one could only provide protection from radioactive fallout in the ash descending after the blast.

Our American entrepreneurial spirit quickly asserted itself, and firms appeared, advertising and knocking on doors to promote their versions of fallout shelters. Previously, these firms had been selling over-priced
mastic coatings for houses, shoddy patio covers, and cheaply built swimming pools. As their practices became exposed, they lost work to reputable contractors and welcomed this opportunity to sell something new to gullible customers. In their rush to be first on the scene, few bothered to gain anything but a vague understanding of what was needed, spending most of their time rehearsing glib sales pitches that would convince susceptible buyers.  Some of them dug the 12 foot deep hole before running off with their payment advances, others went on to pour a slab and erect enclosing masonry walls, but most blew the roof test. They failed to calculate the weight of a three-foot cover of earth, and many a roof collapsed either from its weight or from that plus the weight of the skiploader grading and compacting it. Most of the skiploaders had to be craned out of the collapsed mass of dirt and timber.

I had left a sub-contracting business a year earlier to become a general contractor, and I was finding it more difficult than I had supposed. The grass was not greener on the other side of the fence. The same media which had recommended shelters now gleefully wrote of these disastrous collapses. I began to see a market which could supplement my start-up business. I would build proper shelters, and I would build for blast protection as well as fallout. What good was it to protect against radioactive fallout if the occupants were already squashed dead from the blast? My sales tool would not be glib pitches but a shelter built on my own home property that would serve to showcase my product, as a model home serves a housing tract.  I would have certified plans, progress photos of its construction, data from the Atomic Energy Commission, all that was necessary to show my customers that they were not dealing with a fly-by-night.

Acting on my conviction, I contacted a structural engineer that I knew. I did this with some trepidation. These guys stand at the top of the construction pyramid; even architects defer to them. After the Long Beach earthquake, they had designed the earthquake code which governs all schools built in California. I had found, on the two school additions I had built, the extent to which their word was law. I wasn't sure that he would deign to talk to me, but it turned out that he was available to anyone who could pay his hourly fee. It seemed astronomical then, but it was about what you'd pay a good carpenter today. I found his office less sumptious than I expected; he was sitting at a drafting table when I was ushered in.

  "Blast protection," he mused. "Do you have any idea what that means with a hydrogen bomb? Anything inside the crater is going to be up in the air, part of that radioactive ash they talk about."
"Well, obviously we can't be that close. I was thinking - maybe five miles from the crater center."
"That's what you're going to sell: five-mile-away bomb shelters?"
Sensing sarcasm, I controlled my irritation. "Isn't that better than having to be halfway to San Diego before you only have to worry about fallout?"
He considered that and nodded. "Yes, it would be. Have you thought about this as a community shelter - built in a park or a school yard? What you're talking about would be a lot for a home owner to take on."
I asked if he knew of any interested cities and told him that home owners were the only market so far. Their big need was a contractor they could trust. He nodded and told me to come back in a week. That would give him a chance to read the manual I had brought him from the AEC; he could check some of his sources and do some calculations.

He called before the week was out. When I arrived, he had the plans laid out. My home had a basement, something odd in Southern California, and what he showed me would make it even odder. We would have steps that dropped down three feet from the basement floor to an opening I would have to cut through the basement concrete wall, and this would open into the shelter's vestibule. The door to a side hall was to the left and set into an 18" thick wall, designed to be a radiation barrier. The small hall would hold the chemical toilet and the main room ten feet wide by 20 feet long opened from it. Even on a plan, it looked like a prison cell.

"The outside walls are 12" thick and the roof slab is 8, but it will have 2 grids of 5/8" rebar, spaced 5" apart, one over the other."
"How will I pour concrete through that?"
"You'll have to use a pea-gravel mix and pump it."
He had described the core of the structure and went on to give me the rebar spacing in the walls and floor slab.
I looked at the plan in wonder. "It's a vault."
"You wanted blast protection. Actually, you could survive in this 3 1/2 miles from the crater. AEC doesn't recommend designing for more that 10 PSI over-pressure, so I went with that."
"Ten pounds per square inch. That's not much."
"It's also 1440 pounds per square foot. Think of a Sherman Tank moving over your structure, except the pressure is not only under the treads. The total blast pressure on the roof of the main room would be 144 tons. Your biggest problem will be your door."
I was beginning to get it. "Okay, so a 2 by 6 1/2 door is 13 square feet."
"Times 1,440 equals 18,720. Over nine tons. You've got 3 tons of blast pressure hitting each hinge. Incidentally, I don't design hinges."
"Wow. And if the hinges don't hold - "
"That pressure smashes in and crushes everyone inside."

His plan for that problem was to cut 6x6 timbers and stack them  so they braced the door against the outside wall of the small hall.

"Forget the hinges except for everyday use of the door. You can hold the door through the blast with the timbers but -"
" - how do I get them out after the blast?"
"You got it. The blast will fuse the door and timbers against the wall into a solid mass. Now, let's say you're able to chop all that out and pry open the door. What are you going to find?"
"The remains of my house filling the basement."
"Correct. You need an escape hatch."

He had thought it all out. There would be a 2x2 opening midway up the wall at the other end of the shelter. I would build a steel channel frame with bolts welded around the perimeter, 5" apart, and bolt in a 1/2" thick steel panel to serve as access door. Outside the shelter, I would dig a shaft down to the opening, then fill the shaft with sand and replace the lawn over it. When the surviving occupants wanted to leave the shelter, they would unbolt and lift off the panel, and most of the sand would drop out. They would have an easy dig up to the front lawn, 20 feet from the house and, hopefully, free of excessive debris.

"They'll need a lug wrench down there. One of their never-leave tools. They'll have a lot of nuts to unbolt, and it might be their only way out."

* * *

I took the plans to our City Building Department. The plan checker leafed through the plan sheets, then got out his stamper and began stamping each page.

"Aren't you going to check his specs and details?"
"Nope. We don't have anything in the code about shelters. They're too new. We only issue permits because the federal government tells us we have to."
"How about inspections?"
"Call us the day before you pour and when you're finished."
"This isn't one of those dug-in huts that's going to collapse when they cover it with dirt."
"I hope not. If it does, it's your problem, not ours."

I went home and ordered a truck-mounted backhoe for the next Monday. Over the weekend, I staked out the excavation and reviewed my operation plan. Rather than dig wide to provide for two-side forming, I had decided to dig to the exact outer dimensions of the shelter, form the inside only, and pour against the dirt banks, saving outside forms and backfill.  My superintendent came by from the one job I had going and shook his head.

"Jesus, what if it rains?"
"It never rains in July. You pour most of our footings against dirt banks."
"Not 12 feet down. What if it gets too dry and they start to crumble?"
"I'm going to cover the banks with vinyl sheeting."
"So you get all the banks shaved down - just right - then all your rebar is in place and tied off - you're formed and ready to pour, and two kids crawl under the fence and stomp along the edge. The banks start sluffing off, down over the rebar, and into the pour area. What then?"
"I'd have to tear it all out and start over."
"Without banks."
"I'd better get a watchman."
"I gotta leave. Don't call me again until you're ready to pour, okay? If this were my job, I'd have a heart attack."

I hadn't moved a clod of dirt, and I was already anxious. A structural engineer had given me the plans: a plan checker and my own superintendant had given me their thoughts. But where was my support? Didn't they realize that my success with a model shelter would give future shelter owners an alternative to the con artists?

We will dig and build it in Part Two.

Jack Eiden 

1 comment:

  1. An interesting account of times that were strange in the sense of the apprehension that was ingrained into the country by the Cold War. Your plan sounded good. Now I look forward to hearing the rest of the story.

    I recall that my grandmother who lived in Clarksburg, WV had a bomb shelter in her backyard. I was a young teen when saw it. As I remember it seemed to be a large metal culvert covered over with dirt. She used it for storage of home canned foods and other things and it worked well for that. I wouldn't have wanted to stay inside of there for long.

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