I mentioned the Bridge problem in Northern California in a previous article somewhat about Trump. Here you can see it in more detail. If you love driving down (or up)
Highway 1 past Big Sur that may not happen unless you just drive from Carmel Highlands South and then return for over one year at least before the Pfeiffer Canyon Bridge is rebuilt. So, this is a tremendous inconvenience and may put some businesses both north and south of the Bridge out of business by this summer or a little later.
Since this article was written they have tried a pneumatic hammer (a large one) installed on a crane end. This gives enough down pressure where they can make progress through the cement and rebar on this well built bridge which is going to be very hard to bring down because it is so obviously well built. If the ground had not given away under a pillar of the bridge it likely would have remained there another 50 or even 100 years time.
Begin quote from:
Big Sur: Pfeiffer Canyon Bridge demolition progresses, slowly
Big Sur >> Pfeiffer Canyon Bridge is falling down … very
slowly.The crew demolishing the bridge made considerable progress
Thursday, at least in comparison to ...
Big Sur: Pfeiffer Canyon Bridge demolition progresses, slowly
Big Sur >> Pfeiffer Canyon Bridge is falling down … very slowly.
The crew demolishing the bridge made considerable progress Thursday, at least in comparison to when work began Monday.
Workers modified the crane Wednesday by installing two new valves, extending the crane another 75 feet and removing one piece of the crane, which enabled them to resume the demolition late that afternoon, according to Caltrans spokesman Jim Shivers.
“We now have the free fall with the velocity and the power that we had hoped,” he said.
The 6,000-pound wrecking ball smashed through most of the concrete in the crease where the bridge had buckled at its northern end by late Thursday morning. But the rebar underneath that asphalt helped hold the bridge together and keep it standing.
“I think it’s a testament to the engineers who design and construct these bridges,” Shivers said. “They are designed not to fall apart. We’re seeing here each day that they just don’t fall — that there is precision when they’re built, precision when they’re taken apart. We see mounds of steel rebar that we need to batter at and we’ll use some welding torches to cut it and relieve some of the tension out there.”
Crews used the wrecking ball to “soften up” the concrete bridge deck and allow welders to be lowered into position with the crane to cut the rebar in strategic places. Small chunks of concrete fell from the east side of the bridge and clouds of dust puffed out from the crumbling crack between two sections of the structure. Part of the bridge was leaning against the hillside on the west side of the structure.
“I think probably the side that’s dropping the most is probably bearing against what’s still standing on the column that’s failed, so I think it’s hung up a little bit,” said David Galarza, Caltrans’ structure representative for the project, about the western side of the bridge.
Workers used a hoe ram, also known as hydraulic breaker, Thursday afternoon to try and eliminate the support for that part of the bridge.
“It’s like a jackhammer, but it attaches to an excavator,” Galarza said of the hoe ram. “So the excavator will manipulate it around and it will beat up against it.”
Caltrans chose to demolish the bridge by dropping the wrecking ball, rather than swinging it or using explosives, because of nearby power lines and efforts to mitigate environmental damage, while also expediting the cleanup process.
“We will use equipment via a road that I believe that we will carve out … then we will break these pieces up load them up onto trucks and get them to recycling centers,” Shivers said of the debris removal.
Shivers said data from exploratory drilling done by geotechnical experts, which will help with the construction of the replacement bridge, should be coming in any day now.
“We’ve had instrumentation in the ground that measures the composition of the soil, tells us what’s below our feet,” he said. “There’s also a device across the way (on the southern side of the bridge) that measures the water that is in the soil. The slide (on the southwestern end of the bridge), which caused this damage to the bridge, is still an active slide. It still has a very high water content as best we can tell.”
Caltrans expects the new bridge to be completed in nine to 12 months. The first sections of the new columnless, single-span steel plate girder bridge are expected to arrive in May.
“Many of the pieces for the steel bridge have been ordered, some are in the early stages of fabrication,” Shivers said.
Tommy Wright can be reached at 831-726-4375.
The crew demolishing the bridge made considerable progress Thursday, at least in comparison to when work began Monday.
Workers modified the crane Wednesday by installing two new valves, extending the crane another 75 feet and removing one piece of the crane, which enabled them to resume the demolition late that afternoon, according to Caltrans spokesman Jim Shivers.
“We now have the free fall with the velocity and the power that we had hoped,” he said.
The 6,000-pound wrecking ball smashed through most of the concrete in the crease where the bridge had buckled at its northern end by late Thursday morning. But the rebar underneath that asphalt helped hold the bridge together and keep it standing.
“I think it’s a testament to the engineers who design and construct these bridges,” Shivers said. “They are designed not to fall apart. We’re seeing here each day that they just don’t fall — that there is precision when they’re built, precision when they’re taken apart. We see mounds of steel rebar that we need to batter at and we’ll use some welding torches to cut it and relieve some of the tension out there.”
Crews used the wrecking ball to “soften up” the concrete bridge deck and allow welders to be lowered into position with the crane to cut the rebar in strategic places. Small chunks of concrete fell from the east side of the bridge and clouds of dust puffed out from the crumbling crack between two sections of the structure. Part of the bridge was leaning against the hillside on the west side of the structure.
“I think probably the side that’s dropping the most is probably bearing against what’s still standing on the column that’s failed, so I think it’s hung up a little bit,” said David Galarza, Caltrans’ structure representative for the project, about the western side of the bridge.
Workers used a hoe ram, also known as hydraulic breaker, Thursday afternoon to try and eliminate the support for that part of the bridge.
“It’s like a jackhammer, but it attaches to an excavator,” Galarza said of the hoe ram. “So the excavator will manipulate it around and it will beat up against it.”
Caltrans chose to demolish the bridge by dropping the wrecking ball, rather than swinging it or using explosives, because of nearby power lines and efforts to mitigate environmental damage, while also expediting the cleanup process.
“We will use equipment via a road that I believe that we will carve out … then we will break these pieces up load them up onto trucks and get them to recycling centers,” Shivers said of the debris removal.
Shivers said data from exploratory drilling done by geotechnical experts, which will help with the construction of the replacement bridge, should be coming in any day now.
“We’ve had instrumentation in the ground that measures the composition of the soil, tells us what’s below our feet,” he said. “There’s also a device across the way (on the southern side of the bridge) that measures the water that is in the soil. The slide (on the southwestern end of the bridge), which caused this damage to the bridge, is still an active slide. It still has a very high water content as best we can tell.”
Caltrans expects the new bridge to be completed in nine to 12 months. The first sections of the new columnless, single-span steel plate girder bridge are expected to arrive in May.
“Many of the pieces for the steel bridge have been ordered, some are in the early stages of fabrication,” Shivers said.
Tommy Wright can be reached at 831-726-4375.
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