HEAVY RIGGING • DEEP SHAFT LOWERING • CRANE & STRAND JACK CALCULATOR

TBM Launch Shaft Rigging & Lowering Calculator

Compute ground bearing pressures, tandem crane load sharing, strand jack gantry safety margins, steel matting distribution areas, and descent cycle durations for lowering 150t to 400t TBM cutterheads into sub-surface launch shafts.

01 Shaft Geometry & Rigging Parameters

metric t
meters
meters
kPa
LIVE LIFT PLAN CRITERIA RIGGING APPROVED (SF ≥ 2.5:1)
Total Dynamic Hook Load 299.0 t 659,180 lbs peak factored load
Steel / Timber Matting Area 42.5 m² 457 sq ft distribution
Lowering Cycle Duration 128 min 15.0 m/hr controlled descent
Rigging System Utilization 40.4% within safe working load
Wind Speed Cutoff Limit 9.0 m/s (20 mph) Mandatory shaft hold
Spreader Beam WLL: Minimum 350t Modular Spreader Beam
Shaft Rim Collar Buffer: 1.8 m (5.9 ft minimum radial clearance)
Grommet Sling Spec: 4-Part 64mm Superflex Steel Cable Grommets
ASME B30.26 / B30.5 • Deep Shaft Heavy Lift Protocol CALCULATED LIVE

Deep Shaft Heavy Rigging Physics: TBM Lowering

1. Ground Bearing Pressure & Shaft Retaining Wall Surcharge

Positioning heavy cranes adjacent to deep circular or rectangular slurry-wall shafts exerts immense lateral surcharge pressure on shaft secant piles. Timber or steel distribution mats must spread outrigger and crawler track reactions beyond the active soil failure wedge (45° + φ/2).

Required Area A = (W_crane + W_load × DynamicFactor) / AllowableSoilPressure

2. Strand Jack vs Heavy Mobile Crane Lowering

While 600t-1000t crawler cranes offer mobility, hydraulic strand jack gantry towers eliminate lateral pendulum swing risks inside tight 15-meter shaft clearances. Operating with 18mm high-tensile steel strands, strand jacks provide mechanical wedge grip locks that mechanically fail safe in the event of hydraulic pressure loss.

Descent Time T = (Shaft Depth × 60) / Descent Speed (m/hr)

Need Automated Heavy Rigging & Lift Plans in Your TMS?

Exspeedite Heavy Haul TMS calculates ground bearing pressures, tandem crane sling capacities, and bridge route permits for tunneling and mega-infrastructure projects.

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