PBS Precast Shell System for Reinforced Concrete Frames
Factory-made fibre-reinforced concrete shells for columns, beams, slabs and shear walls. Shells are set on site, reinforced and filled with concrete, so the structure is designed and behaves as cast-in-place RC, without building or stripping formwork.
Precast the formwork, cast the structure
PBS stands for Prefabricated Building Shell System of RC structure. Instead of precasting the whole concrete element, we precast only its outer skin: a thin shell of fibre-reinforced concrete in the shape of the column, beam, slab or wall. On site the shells are set, reinforcement is placed inside, and concrete is poured to form a monolithic frame.
The result is an ordinary reinforced concrete structure. It is designed to the normal RC code, its joints are cast-in-place, and there are no grouted sleeves to inspect. What changes is the site work: no timber or aluminium formwork is built, struck or cleaned, and the shell stays as the finished surface.
PBS is developed and produced by Guangdong Guiguan Green Building Technology Co., Ltd., the green building company of Guiguan Group. It has compiled the PBS design standard atlas and the PBS application technical specification. See group companies.
- Precast shell + site assembly + monolithic pour
- Standard RC design, no special connection code
- Shell remains as the fair-faced finish
Shells for every part of the RC frame
Five component types: shell columns, shell beams, floor slabs, shear walls and haunch panels.
Hollow column shells, filled on site
Square or rectangular shells set on the floor below and braced. Column cages are dropped in or assembled inside, then the core is poured with the floor.
- Replaces column formwork completely
- Shell joints sealed at floor level
- Same cover and rebar as cast-in-place
U-shaped beam shells
Open-top U-shells span between columns and carry the wet concrete with light props. Stirrups and bars are placed inside; the top is cast with the slab.
- Haunch panels shape beam-slab junctions
- Light props instead of full formwork
- Continuous rebar through joints
Slab soffit as permanent formwork
Floors use the truss floor deck: a steel bar truss on a fibre-reinforced concrete base board, about 28 kg/m², Class A fire rated.
- Panel 1,220 × 2,440 mm
- Truss height 70–100 mm
- Props only above 2 m span
Double-skin wall shells
Two fibre-reinforced concrete skins form the faces of the wall. Reinforcement is placed between them and the cavity is poured, giving a solid cast-in-place wall.
- No wall formwork or ties to remove
- Openings and sleeves set in the factory
- Faces ready for paint or tile
From RC design to a monolithic frame in six steps
Digital design
RC design is split into shell components in BIM; drawings and part lists issued.
Factory production
Shells cast in fibre-reinforced concrete, cured and coded per floor.
Logistics
Light shells stacked and shipped in floor sequence.
Site assembly
Shells set, aligned and braced with light props.
Rebar and pour
Cages placed, then columns, beams and slab poured together.
Digital management
Parts tracked through production and installation by MES.
Work moves to the factory
Formwork building, the slowest site trade, becomes a controlled factory process.
Fewer skilled site trades
No carpenters building and striking formwork on every floor.
Less site waste
No timber formwork to discard, less cleaning and less wet-trade debris.
PBS vs cast-in-place vs precast concrete (PC)
PBS keeps the structural certainty of cast-in-place concrete and the site speed of prefabrication.
| PBS precast shell | Cast-in-place RC | Precast concrete (PC) | |
|---|---|---|---|
| Site formwork | None: shell is permanent formwork | Full formwork every floor | None, but grouting and joint casting |
| Structural behaviour | Monolithic RC, same as cast-in-place | Monolithic RC | Depends on joints; grouted sleeves or wet joints |
| Design code | Standard RC design | Standard RC design | Precast design and connection detailing |
| Component weight | Light shells, small cranes | Not applicable | Heavy elements, typically 2–10 t |
| Critical QC point | Shell alignment and pour | Formwork and pour | Grouted sleeve filling, hard to inspect |
| Transport | Light, stackable | Not applicable | Heavy, special trailers |
| Surface finish | Fair-faced shell | Depends on formwork | Factory finish |
| Site speed | Fast | Slowest | Fast, crane dependent |
General comparison. Actual programme and cost depend on floor plan repetition, spans, crane access and local labour rates.
PBS component ranges
Component sizes follow your RC design. These are the ranges we usually produce.
| Item | Typical range |
|---|---|
| Shell material | Fibre-reinforced concrete flat board and formed shells |
| Shell wall thickness | 15–30 mm typical |
| Column shell section | 400 × 400 to 1,200 × 1,200 mm typical |
| Beam shell depth | 400–1,200 mm typical |
| Component length | One storey height or one bay span, ≤ 6 m typical |
| Slab system | Truss floor deck, 1,220 × 2,440 mm, ≈ 28 kg/m² |
| Fire performance of shell | Non-combustible, Class A board |
| Design basis | RC design to project code; PBS design standard atlas and technical specification |
Reinforcement, connections, seismic and fire details are confirmed per project from the structural drawings.
Steel frame, PBS cores and truss deck in one package
Many buildings mix systems: steel for long spans and towers, concrete for cores, ramps and fire compartments. Guiguan Group supplies all of them under one programme. Steel members come from Guangdong Guiguan Construction Group; PBS shells and floor deck from Guangdong Guiguan Green Building Technology. One BIM model, one delivery schedule and one coded site layout.
Where PBS fits
Schools, hospitals, public buildings
Fast programmes on occupied or constrained sites with fewer site trades.
Related services
Sa2.5 blasting, epoxy zinc-rich systems, hot-dip galvanizing and intumescent coating.
100% UT on CJP welds, dimensional reports, MTC 3.1, packing and port logistics.
PBS questions from engineers
Send your RC drawings and we return a component split and price.
Is a PBS building designed differently from a cast-in-place building?
No. The structure is designed as normal reinforced concrete. The shell replaces formwork and stays as the finish; reinforcement and joints are cast-in-place.
How is PBS different from precast concrete (PC)?
PC precasts the full element and connects it on site with grouted sleeves or wet joints. PBS precasts only a thin shell, so components are light and the joints are monolithic cast-in-place concrete.
Which components are available?
Shell columns, shell beams, floor slabs (truss floor deck), shear walls and haunch panels for beam-slab junctions.
Who manufactures PBS?
Guangdong Guiguan Green Building Technology Co., Ltd., a subsidiary of Guiguan Group, which also produces our patented truss floor deck.
Can PBS be exported?
Yes. Shells are light and stackable for container shipment. Projects outside China are reviewed against the local concrete code with the engineer of record before production.
Send your drawings. Get a 24-hour BOM and FOB price.
DWG, IFC, Tekla or PDF. Engineering review by our Tekla team, from 50 t or 2,000 m².