CA: Engineers Prepare Test for HSR Bridge in Madera

June 24--It's not actual construction, but the appearance of a large crane and workers assembling steel rebar marks a significant test as high-speed-rail engineers design a major bridge near Madera.

Workers for Tutor Perini/Zachry/Parsons, the contracting consortium hired to design and build the first 29-mile stretch between Madera and Fresno of the statewide bullet-train line, spent Tuesday wiring together a steel-frame tubular cage that is about 10 feet in diameter. Once the cage is completed, it will be fitted with sensors and lowered by crane into an 80-foot-deep hole and filled with concrete, said Hugo Mejia, design and construction manager for the California High-Speed Rail Authority.

It's called a load test pile, and once the concrete is cured, engineers will stress the buried structure to its breaking point, Mejia said. Where and how it fails will help engineers determine whether their design will stand up to the demands of a 1,000-foot viaduct, or elevated track, planned to span the Fresno River, Highway 145 and Raymond Road at the eastern edge of Madera.

The testing site on the north side of Highway 145, just west of the BNSF Railway freight tracks, is eye-catching. But the rail authority notes that it's only testing for engineering designs. The agency continues to acquire the land it needs for the railroad right of way. Diana Gomez, the agency's Central Valley regional director, said the authority has secured between 40 and 50 parcels from landowners so far. The authority hopes to get nearly 400 parcels in the Madera-Fresno region.

Gomez said some building demolition work in downtown Fresno is likely to be the first substantial pre-construction activity that people will notice over the next month or two. She said some events are planned next week in Fresno to let residents know about progress and demolition that they'll see coming up.

This story will be updated

The reporter can be reached at (559) 441-6319, or @tsheehan on Twitter.

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