I was griping to my project inspector about how millions are spent to keep drunks from driving into rivers, yet a plastic orange barrel, without a reduced speed, is acceptable for a workers exposed to the same drunks.Of course he agreed with me, since he has the same exposure.
Anyway, back to the subject, which is guardrail.
Guardrail is made from rolled sheet metal, which gives it a shape that resists bending, yet allows it to remain lightweight. The depth of the rail is 3 inches, after rolling. The rail is hot dip galvanized after rolling, which prevents corrosion for decades; as long as the galvanize coating isn't damage. A typical section is light enough for two men to carry, and a small crew can place it without heavy equipment. Although this isn't the preferred method for production placement, it allows the minimum amount of people to replace small, damaged sections.
A typical rail section is a little longer than 25 feet, which allows for bolting the sections together. Holes in the rail are slotted, which allows some play during placement. Drilling for a perfectly positioned post isn't impossible, but not having the slots would make placement much more expensive. Sections are bolted with 5/8 inch hot dip galvanized button head bolts. The button head slides into the slotted hole, and allows tightening without a backup wrench. Eight bolts hold each section together and the sections are always overlapped so the lap faces away from traffic. This prevents a section torn loose in an accident from becoming a lethal lance, until the section is repaired.
The domed posts are treated wood 6 feet 3 inches long, and 7 inches in diameter. Bolt holes are drilled in the posts. When buried to the correct depth of 42 inches, the hole is 25 inches above the edge of the paving, which is the correct height for the center of the rail. The standard spacing is 6 feet 3 inches, although that spacing is less at the connection to bridges.
The edge of the paving is the preferred position for the face of guardrail. On a highway with a shoulder, that's the edge of the shoulder. On curbed streets, that's the back of the curb. With a typical section of rail, with 7 inch blockouts, that means the center of the post is 13-1/2 inches from the face of the rail.
Why am I telling you all this? Because there are years of study, experience and engineering involved with guardrail. Many lives were saved over the years due to guardrail, and if undamaged, a section can last the lifetime of an individual. I'm removing a section that was placed when I was a child. If changing the location wasn't required for a bridge rail retrofit, the section would have remained as long as nothing was required for its removal.
Still, it chaps my ass to think of all the money spent to keep people safe, yet those that place what saves lives are so inconsequential to bureaucrats, they're not willing to do the paperwork, and spend the money for a sign that mandates people slow down when they're working on the guardrail that keeps the attorneys at bay.
In Case You've Wondered
My blog is where my wandering thoughts are interspersed with stuff I made up. So, if while reading you find yourself confused about the context, don't feel alone. I get confused, too.
If you're here for the stories, I started another blog: scratchingforchange.blogspot.com
One other thing: sometimes I write words you refuse to use in front of children, or polite company, unless you have a flat tire, or hit your thumb with a hammer.
I don't use them to offend; I use them to embellish.
Sunday, October 19, 2014
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In Alabama we must reduce our speed when workers are present at construction sites. Plus, the fine is double if we go faster than the posted speed limit at constructions sites along the road. I may have said that before. At any rate, a county cop pulled me over with no men present. I often cringe as I pass men and wonder how they feel about their working conditions. Are there not signs at your construction saying that the speed is reduced and the fines are doubled?ReplyDelete
Fines are double for violations, but there are no speed laws for construction workers. Cops, wreckers, ambulances and TxDot workers are protected by laws that mandate a reduction in speed. Private contractor workers are told to go suck eggs.Delete