CABLEWAY NOT CRANE TO MOVE PRECAST PANELS

[boonmec]

Power lines and a tree on the open sides of a 50 by 100 ft corner lot impede the use of a crane to place precast floor and wall panels (similar to Superior Walls) for a three-story house and detached garage. Does anyone have any experience in the specification and setup of a practical cableway (highline) to place such panels? The conjoined footings describe an approximate rectangle 30 by 74 ft. Would extending the footings, to resemble a streched straight-angled # sign, be a practical means of providing a base to cableway uprights? How about earth anchors for tie-backs? Any observations are welcome.

 

[civilperson]

A truck mounted hydraulic crane in the lot can lift any component that is brought under the lines and into the lot. Necessary clearance to the lines is dependent on voltage, probably less than 84" for any voltage in your neighborhood.

 

[boonmec]

Thanks. A heavy truck crane can be placed diagonally at the open corner of the lot, after removing street name and stop signs. An 18 wheeler's trailer, carrying the panels, can be placed on the lot on the long open side(100 ft)far enough away from the pole line. The problem arises from a city bus which goes by this corner. The floor panels are near 30 ft by 4 ft and not all of the various panels can be lot delivered on one trailer, requiring setup and removal of the heavy crane more than once during off peak transit hours, leading to certain expenses. The heaviest floor panels, thin shell with thin gauge composite action joists, are of the order of 4,000 lbs. The cableway would actually be twinned, one cable more or less atop the centerline of each of the long side (74 ft) footings: they would stay in place until termination. The "front" uprights of each cableway, near the short open lot side (50 ft), would be placed such that succesive panel carrying trailers could be backed in, between the "front" house footing and these uprights (near the "front" tree). Panels would then be picked up from the trailers: lateral wall panels by fall lines from each respective cableway, floor panels by fall lines from both cableways at the same time, and front/back wall panels by a gantry beam (aluminum?) supported by the fall lines from both cables. The recent failure of the Hoover dam bypass bridge cableway crane has been noted, causing concern about effective and economical earth anchors (high capacity units such as from American Earth Anchors?).

 

[civilperson]

A hydraulic extending boom crane is capable of 16000 pounds lift at 50 degrees and proportionately less at lower angles. Can be driven to your site and set up at the site in less than fifteen minutes and equally quick in demoblization. Ask the local crane specialists what the rate is and you will find nothing can compete on a cost basis.

 

[boonmec]

Thanks again. The quote for a 700 series crane with a 95 ft jib at an offset of 25 degrees yielding a clearance of 40 ft (all deemed required due to the only location suitable) was $220 an hour based on an 8 hour minimum. Assuming three or four individual sessions are required as a minimum, due to the above described circumstances, this is where the interest for investigating an alternative comes from.