RYS - Precast Lifting Design

DESIGN PRECAST LIFTING USING PRESTRESSED STRANDS OR REINFORCEMENT BARS

Notes

Design Code,

Weight of precast element, wt_precast = tons (metric)

Surface area of precast element, A_precast = m² (for adhesion force calc during demoulding, if no adhesion put 0 )

Design Criteria

Lifting mechanism design for ;
Demoulding Only Installation Only Both

Minimum Global FOS,     fos_demoulding N/mm²        fos_installation N/mm²

Concrete CUBE strength,
f_{cu_demoulding} N/mm²        f_{cu_installation} N/mm² , cube strength

Panel Configuration During lifting,
at casting yard =        at site (installation) =
(Note : All 3D casting will assume poor bonding condition as the strands are placed at top of cast)

Dynamic Factor for crane lifting:,
at casting yard =      at site =

By lifting elements with a chain, there is a load increase resulting from the angle of inclination.
Angle of lifting sling to the vertical β ,
at casting yard =      at site =

Adhesion to mould (oiled steel mould)

Nos lifting_points ,
Demoulding stage nos     Installation stage nos

Balanced lifting conditions used ? , select

All balanced lifting MUST use chain blocks and pulleys to provide equal distribution of loads. The center of gravity of the the lifting hooks must also coincide with the center of gravity of the precast elements.

Lifting mechanism used (choose one)

lifting using prestressed strands
φ_strands , mm strands_nos , mm f_pst = N/mm²

lifting using Propriety Lifting Anchors

lifting using reinforcement bars
φ_rebar , mm rebars_nos , mm f_st = N/mm²
Angle (Horizontal) from plane of rebar = degrees

h₁= mm
b₁= mm

NOTE
ALL LIFTING POINTS TO BE SYMETRICALLY ARRANGED AROUND CENTROID OF PRECAST PANEL

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