2009 Face Conference Wa Crane Sjostrom

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WAFACENIOSH AlaskaLabor Neighbor RadioConstruction Industry

WASHTIPSSSMBABuild It SmartResConAGC ABC

JATC

TCOCWSDOTWorker Memorial DayAmerican Society of Safety EngineersCrane Rule

Portland 2009

Washington FACE

Crane Incident Bellevue, WA

Tom Sjostrom CPEA

General Contractor: WashingtonCrane Owner: Oregon

Crane Erected by: WashingtonCrane Operator: Washington

Crane Manufacturer: Liebherr (Germany)

Seattle engineering firm designed the base

Winds may have weakened crane

Bellevue crane appeared to be leaning earlier

Photo from The Westin Bellevue on Oct. 10.

The yellow crane, which would collapse on Nov. 16, appears to be tilting when compared to the white crane in the foreground.

Investigators looked at photos, and said the yellow crane appears to be tilting 2 to 3 feet at the top.

Cranes are allowed to lean somewhat

-- about an inch for every 40 feet of height, according to national standards.

That calculates to 5.25 inches of permissible tilt for the 210-feet high crane that collapsed

-- which is barely noticeable to the eye.

But the Bellevue crane, which heavily damaged three buildings and killed a man in his apartment as it fell,

--appears as if it was leaning more than 3 feet at the top.

The cab of the construction crane that collapsed on can be seen laying against the Civica Office Commons building.

The crane was mounted on an unusual foundation of steel I-beams instead of the customary concrete slab.

The crane’s tower was bent 15 feet above the foundation.

Firefighters and rescue personal clean up debris as they continue searching for victims in the Plaza 305 building.

Crane Accident Bellevue, WA

Dozens of bolts and welds failed where the base of the crane was secured.

The bolts connected the crane to large steel beams and a concrete slab in an underground parking garage at a corner of the construction site.

L&I investigators noted that the crane sat on an unusual base.

It reportedly had been repositioned from a cement foundation that was constructed when the project first began in 2001.

Crane operator control cab. The operator suffered only minor injuries.

GAPS IN SAFETY CONTROLS

No safety inspections at the site prior to the incident.

Cranes must be inspected before each use, but it is usually done by the operator.

A statewide crane-safety organization created after the deadly 1994 Kingdome crane incident was no longer active.

A section of the construction crane that collapsed rests against the front of the Pinnacle Bell Centre.

The victim was in a fourth-floor apartment of the building. \\

High winds earlier in the week may have weakened metal fasteners in the base of the crane .

Investigators also looked into whether the crane was allowed to "weathervane," or swing freely, during windstorms before the collapse.

A failure to do so by the crane operator would have put more stress on the massive structure, experts say.

If the crane is not in weathervane mode, the torque from the wind load on the boom can contribute, at least in part, to failure.

The torque failure is similar to twisting metal until it causes metal stress and break or bend.

Workers remove debris the Pinnacle Bell Centre apartments

A Second Crane in Bellevue has problems December

Crane's cracks blamed on water, iceLabor and Industries agency issues call for statewide inspections

State investigators are blaming water and ice for the long cracks that developed in the 300-foot-high tower construction crane in downtown Bellevue that was suddenly branded a safety hazard and dismantled over the weekend.

Tower Crane employees work to stabilize a damaged construction crane; here, they pull themselves into position to add more clamps to the crane.

Tower Crane employees inspect the damaged crane where cracks were discovered in downtown Bellevue before it is dismantled.

Third Bellevue crane found to have flaw

A 225-foot tower crane in downtown Bellevue was being repaired with welding torches after a 2-foot "hairline" crack was found near the top of the tower.

Fourth Tower Crane Crack Identified

Neglect blamed for rash of crane failuresMaintenance and inspections have been lax, some say