Concrete is a technology... Ultra-high-performance concrete — UHPC — runs eighteen to thirty-five thousand psi, ten times the strength of the mix in American bridges today, tensile strength twice normal, chloride permeability under ten percent, freeze-thaw shrug. Machine-made sand concrete replaces river sand with precision-crushed aggregate engineered at the grain level and saved one Chinese province $3.19 billion on a single bridge program. Concrete-filled steel tubular arch systems — CFST — now span six hundred meters across Chinese canyons. Prefabricated modular bridge spans are stockpiled in fields next to the bridges they will one day replace, ready to be craned in when the live span is hit. Six bridges in seventy-two hours. The Iranians did this last week. The Chinese can do it at greater span than anyone has ever done it.
Go ahead. Name an American cement company. The sentence doesn’t end. That’s the sentence-ending sentence. The country that cannot pour its own concrete is the United States of America. Meanwhile six Iranian railway bridges went down and came back up in seventy-two hours. The method is called the Bridge Rapid Replacement System. In 2019 somebody sat in Tehran and said what if they bomb the bridges, and somebody else said we should put another bridge next to every bridge, and somebody else said yes, and they did it. Six times. In concrete...
Meanwhile in Guizhou there is a canyon and a bridge across the canyon, six hundred twenty-five meters of concrete, lifted into place with a hoisting system that did not exist fifteen years ago. The Chinese hold every world record for arch bridge span. Every single one. The seminary cannot pour a sidewalk in Baltimore that doesn’t crack in four years. The seminary had a harbor bridge in Baltimore and a ship bumped it and the bridge fell in the water. The seminary watched the ship coming for an hour.
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