Steel structure manufacturer since 2009 · 8 fabrication bases in China
Steel Buildings
Steel and composite frames for towers, podiums and public buildings
Tower steel is thick, heavy and full of interfaces. Plates of 60 mm and more need through-thickness grades and preheat. Columns carry rebar and studs. Every splice level follows the concrete pour. These are the points we check before shop drawings.
241 m
Tallest tower, Zengcheng C1
18,472 t
CGN HQ steel, 3 towers
Q420GJC
Thick-plate grade used
6,500 t
Xintang railway station
Fit
When a steel or composite frame makes sense
A good fit when
- Towers over 150 m where column size limits floor area
- Long-span floors for offices, halls and hospitals
- Transfer levels and cantilevers
- Floors erected ahead of concrete to save programme
- Station roofs and atria with long spans
Think twice when
- Residential towers with small spans where flat-slab concrete is cheap
- Exposed steel with no fire protection budget
- Sites without tower crane capacity for heavy column pieces
Frame systems
SRC, CFT or bare steel
| System | Uso típico | Strength | Watch out for |
|---|---|---|---|
| SRC (steel-reinforced concrete) columns | Tower perimeter and core | Stiffness, fire cover from concrete | Rebar holes and stud clashes |
| CFT (concrete-filled steel tube) | Podium and mega columns | Small section, no formwork | Filling quality, vent and pour holes |
| Bare steel with composite floors | Offices, hospitals, schools | Fast, long spans | Fire protection, floor vibration |
| Outriggers and belt trusses | Super-tall towers | Controls drift | Heavy nodes, erection sequence |
| Cerchas de techo de gran luz | Stations, halls, atria | Column-free space | Transport length, trial assembly |
Thick plate
Lamellar tearing, Z-grades and preheat
Thick plates loaded through their thickness by large welds can tear in layers. It is prevented at the material order, not at inspection.
| Risk | Control | Norma |
|---|---|---|
| Lamellar tearing at T-joints | Through-thickness grade Z15, Z25 or Z35 ordered for plates loaded through thickness | GB/T 5313, EN 10164 |
| Laminations in the plate | Ultrasonic testing of plate before cutting | GB/T 2970, EN 10160 |
| Cold cracking of thick welds | Preheat and interpass temperature by thickness and carbon equivalent | GB 50661, AWS D1.1, EN 1011-2 |
| Distortion of box columns | Weld sequence, restraint, post-weld correction | Our procedure qualification |
| Hidden defects in full-penetration welds | 100% UT for grade 1 welds | GB 50205, GB/T 11345 |
Plate thickness limits we fabricate: to confirm in writing.
Interfaces
Steel, rebar and concrete in one model
Most rework on composite towers comes from interfaces drawn by different teams at different revisions.
- Rebar holes, couplers and studs placed from a combined model
- CFT vent and pour holes sized and located for the concrete method
- Splice heights set with the pour sequence
- Deck edge trims and pour stops detailed with the steel
- Curtain wall embeds fabricated into the frame
From our engineers
Three tower problems solved in the shop
Column shortening. Steel and concrete columns shorten differently under load and creep. Your engineer sets the compensation; we add it to each column tier length.
Verticality. Columns are surveyed every tier. The erection manual sets shim and splice adjustment limits.
Piece weight. Tower crane capacity at the working radius sets column piece weight and splice levels, so the crane study comes before shop drawings.
Montaje
How a steel tower goes up
01
Crane study
Capacity sets piece weight and splices.
02
Column tiers
Two or three floors per tier.
03
Beams and bracing
Frame closed and plumbed.
04
Cubierta del piso
Deck laid, studs welded.
05
Concrete
Pours follow steel by agreed floors.
06
Survey
Verticality corrected each tier.
High-rise projects
Towers and public buildings
Do you design the tower structure?
For towers, the design institute or your engineer of record usually designs it. We do connection design, shop drawings, fabrication, and erection on Chinese projects.
When do we need Z-grade plate?
When a plate is loaded through its thickness by large welds, typically column flanges at beam joints. Your engineer names the grade; we flag joints where it appears missing.
What is the heaviest column piece you ship?
Up to about 40 t per piece; the site crane usually sets the real limit.
Do you weld shear studs in the shop?
Column and beam studs are shop-welded where they do not obstruct erection. Deck studs are site-welded through the deck.
Can you fabricate to Eurocode or AISC?
Yes, to EN 1090-2 or AISC 303 execution requirements named in your specification. We do not hold EN 1090 certification.
High-rise frame
Send the column and beam schedule
We check plate grades, SRC interfaces, splice levels and piece weights with the quote.