NCCER Tower Crane case studies
NCCER Tower Crane · Put your knowledge to work in context.
NCCER is an independent 501(c)(3) nonprofit educational foundation created in 1996 that provides industry-recognized credentials and accreditation across construction trades. Within its credentials and certifications catalog, NCCER lists "Crane, Rigger & Signal Person Certifications" alongside other programs such as Construction Superintendent Certification, Construction Foreman Certification, and Construction Site Safety Credentials. The NCCER Tower Crane case studies are 5 cases and about 3,766 words.
1Foundation Undermined by Excavation After Rain
A 50 m jib tower crane is founded on a 6 m by 6 m reinforced concrete pad beside a 5 m deep utility excavation. The pad edge is 4 m from the excavation slope.
800 words, about 4 min2Damaged Used Mast Section and Reused Bolts
A crew is erecting a used flat-top tower crane with a 55 m jib. During pre-erection inspection, a 2.4 m mast section is found with a 20 mm deep dent in a main chord 150 mm from a splice hole and a 40 mm crack in a diagonal-to-chord weld.
741 words, about 4 min3Climbing Operation Above Wind Limit and Loss of Guide Roller Contact
A tower crane is being climbed from 60 m to 66 m under a manufacturer's procedure that limits climbing to 20 mph wind at the mast top. The mast-top anemometer reads 18 mph steady with 26 mph gusts; the site weather app at ground level shows 12 mph.
716 words, about 4 min4Near-Capacity Panel Lift With Sail Area and LMI Warning
An 8 t maximum-capacity tower crane is charted at 3.4 t for a 45 m radius. The lift is a 3.0 t prefabricated wall panel measuring 6 m by 3 m, giving about 18 m² of sail area.
757 words, about 4 min5Dismantling Sequence Error and Assist Crane Set on a Vault
A 55 m tower crane is being dismantled. The assist crane is a 100 t truck crane set on compacted fill over a basement vault.
752 words, about 4 min