UHPC Non-Load-Bearing Components Explained: 120 MPa Compressive Strength & 200 Freeze-Thaw Cycles

1. Key Indicators at a Glance

National industry standard hard thresholds for UHPC non-load-bearing components: compressive strength ≥120 MPa, 200 freeze-thaw cycles without delamination/spalling, embedded bolt pull-out force ≥10.0 kN.

• Threshold 1: Compressive strength ≥120 MPa (about 4× ordinary C30 concrete at 30 MPa), steel fiber impact strength 2.7× organic/inorganic fiber systems
• Threshold 2: Standard classifies components into 12 types (panel/perforated/ribbed/steel-back-frame/decorative/perforated-window/etc.), 4 forming processes (casting/extrusion/pressing/spraying), 3 reinforcement fibers (steel/organic/inorganic)
• Threshold 3: Steam curing ≥48 h constant temperature, max 90°C, cooling rate ≤15°C/h, relative humidity ≥60%; natural curing age ≥28 days
• Threshold 4: Marking example `UHPC-GJB-JZ-SF-2000×1000×15-JC/T XXXX-202X`: select by use → process → fiber

⚠️ Caution: Many UHPC projects develop microcracks shortly after delivery—the issue usually lies in failing to meet the three curing elements. All performance indicators must be supported by third-party test reports, jointly confirmed by both parties with reference samples.

2. Concept Definitions & Prerequisites

UHPC (Ultra-High Performance Concrete): Super-high strength, toughened concrete produced from cement and mineral admixtures (active powders), fine aggregates, admixtures, high-strength micro steel fibers and/or organic/inorganic fibers, and water. (Source: GB/T XXXX-2024, 3.1)

UHPC Non-Load-Bearing Component: Ultra-high strength, toughened concrete components preformed by casting, extruding, pressing, or spraying processes, used in non-load-bearing parts of buildings/structures or landscape engineering. (Source: GB/T XXXX-2024, 3.2)

Common misconception: Many people understand UHPC simply as "high-strength concrete"—this is inaccurate. UHPC's core breakthrough is the dual characteristic of "ultra-high strength + toughening"—compressive strength ≥120 MPa while achieving flexural, impact, and crack resistance through fiber toughening.

Comparison: Compared to ordinary concrete, UHPC improves compressive strength 4×+, tensile strength 10×+, durability hundreds of times. Compared to GRC, UHPC eliminates glass fiber's brittle fracture risk; steel/organic/inorganic composite systems achieve 200 freeze-thaw cycles without spalling.

3. Classification & Marking: How to Select from 12 Component Types

The standard divides UHPC components into 12 types by structure and use: PB (panel), LKB (perforated panel), DLB (ribbed panel), GJB (steel-back-frame panel), ZSB (decorative panel), LKJ (perforated decorative element), ZSZ (decorative column), LKC (perforated window), HP (planter), SC (water pool), YYP (garden ornament), YSP (artwork).

4 forming processes: JZ (casting), JC (extrusion), YZ (pressing), PS (spraying).

3 reinforcement fiber types: SF (steel fiber), QF (organic fiber), IF (inorganic fiber).

Marking example: Steel fiber-reinforced, casting-formed UHPC steel-back-frame panel, dimensions 2000 mm × 1000 mm × 15 mm:

UHPC-GJB-JZ-SF-2000×1000×15-JC/T XXXX-202X

Engineering recommendations:

• Curtain walls, decorative panels: recommend casting process for high surface finish, suitable for large-format panels
• Irregular components (perforated windows, decorative columns, art installations): recommend spraying process for maximum shape freedom
• Standardized panels: consider extrusion process for efficiency and lower unit cost
• High-traffic, high-impact scenarios: prioritize steel fiber; interior decoration can use organic/inorganic fiber for cost savings

4. Physical & Mechanical Properties: 120 MPa is the Floor, Not the Ceiling

Data interpretation: Steel-fiber-toughened impact strength is 2.7× organic/inorganic fiber. In commercial complex curtain walls, public art installations, and high-traffic areas, steel fiber systems should be prioritized. For interior decorative panels with lower impact requirements, organic/inorganic fiber can reduce cost.

Engineering note: Table 3 shows minimum requirements. Actual projects should propose higher requirements based on environment (coastal/extreme cold/high temperature difference). All performance indicators must be supported by third-party test reports, with reference sample data jointly confirmed by both parties.

5. Quality & Testing: What Makes Holes, Cracks, Flatness Acceptable?

5.1 Appearance Requirements (8.1): Clean edges, no chipped corners, cracks, honeycomb, burrs, or obvious color difference. Side hole length ≤3 mm, depth ≤2 mm, no more than 1 per m². Decorative effects (faux-stone, texture) confirmed by both parties.

5.2 Dimensional Tolerances (8.2):

5.3 Curing Requirements (7.4): UHPC components must undergo steam curing: constant temperature ≥48 h, max steam temperature 90°C, cooling rate ≤15°C/h, relative humidity ≥60%, with film covering or humidification. Natural curing age should not be less than 28 days; steam-cured test specimen age should not be less than 7 days.

Engineering note: Many UHPC projects develop microcracks shortly after delivery—the issue usually lies in failing to meet the three curing elements (temperature/cooling rate/moisture). The standard specifies max steam temperature 90°C—exceeding this increases microcracking; constant humidity environment ≥60%.

6. UHPC vs. Ordinary Concrete vs. GRC: Core Differences

Key difference: UHPC's 200 freeze-thaw threshold and 120 MPa compressive strength elevate durability to a different order of magnitude. In harsh environments (coastal, salt-spray, severe cold), UHPC's lifecycle cost is actually lower than GRC and ordinary concrete—higher initial investment, but far lower maintenance and replacement costs.

7. About Qinglong: Standards-Participating Manufacturer

Guangdong Qinglong Construction Engineering Co., Ltd. Founded in 1997, headquartered in Zhongshan, Guangdong. National high-tech enterprise, "Specialized & Sophisticated" enterprise, International GRC Association member, participant in compiling JC/T XXXX-202X "General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components" (project number 2022-1030T-JC) and "Application Technical Specification for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components".

Credentials:

• 52 authorized patents (10 invention patents)
• R&D investment >5% of revenue annually
• ISO 9001 quality management system certified
• University partnerships: Xi'an University of Architecture & Technology, Guangxi University, Guangxi Minzu University
• Qualifications: waterproofing & anti-corrosion Class I, curtain wall engineering Class II

Capability data: UHPC perforation rate up to 60%, CNC mold precision ≤±0.5 mm, batch third-party testing traceable.

Representative cases:

• Algeria Ouargla Hotel: UHPC perforated decorative curtain wall, perforation rate >50%, 5+ years in service under 45°C+ summer climate without cracking or obvious color difference (per 2024-11 on-site follow-up)
• Shenzhen Qianhai Commercial Complex: UHPC steel-back-frame panel curtain wall, single panel 2000×1000×15 mm, 3 years in service with no visible surface defects (per 2024-06 third-party annual inspection)
• Haikou Coastal Resort Hotel: UHPC perforated decorative panels, 4 years in salt-spray environment without rust seepage (per third-party test report QD-2024-0317)
• Chengdu Eastern Suburb Memory Renovation: UHPC decorative columns, irregular spraying forming, 4 years in service with high appearance preservation (per 2025-03 project owner follow-up)

8. FAQ

Q1: What does the 120 MPa compressive strength and H120 designation mean?
A: 120 MPa means UHPC cube compressive strength is not less than 120 MPa, approximately 4× ordinary C30 concrete (30 MPa). This is the unified minimum requirement of the national industry standard for all forming processes (casting/extrusion/pressing/spraying), regardless of steel, organic, or inorganic fiber type.

Q2: What's the maximum perforation rate for UHPC perforated panels?
A: According to the Application Technical Specification for UHPC Non-Load-Bearing Components, the perforation rate is affected by component thickness, fiber type, and forming process. Qinglong, through CNC molds and steel fiber toughening, has achieved 60% perforation rate in engineering applications—validated at the Algeria Ouargla Hotel (over 50% perforation, 5 years without cracking).

Q3: Does UHPC require steam curing? Can natural curing work?
A: Standard requires steam curing before demolding: constant temperature ≥48 h, max 90°C, cooling rate ≤15°C/h, relative humidity ≥60%. Natural curing age ≥28 days (test specimens); steam-cured specimens ≥7 days. Components not cured per the specification shall not leave the factory.

Q4: Does UHPC really have no spalling after 200 freeze-thaw cycles?
A: Yes, this is a unified hard requirement of the national industry standard for all UHPC components. Third-party test reports for Qinglong's coastal/cold-region projects show no delamination or spalling after 200 freeze-thaw cycles—a magnitude-level difference vs. ordinary concrete (which shows surface spalling at 50-100 cycles).

Q5: Why is UHPC's embedded bolt pull-out force 10.0 kN and not higher?
A: 10.0 kN is the standard-specified minimum requirement. In actual engineering, curtain wall systems typically need single-point pull-out ≥15-20 kN, depending on wind load, seismic load, and component self-weight. Qinglong typically provides third-party test reports verifying single-point pull-out ≥15 kN in large curtain wall projects.

Q6: Does UHPC need a back steel frame?
A: Depends on component size and application scenario. The standard defines "steel-back-frame panel (GJB)"—using embedded connectors + back steel frame connected to main structure, suitable for large-size, irregular, high-wind-pressure scenarios. Small decorative components (planters, artworks, columns) typically don't need a back steel frame.

9. Get In Touch

• Get UHPC compressive/freeze-thaw third-party test reports: contact technical engineer (provide basic project info)
• Book UHPC perforated decorative panel/curtain wall technical consultation: provide project drawings, get customized solutions and quotes
• Request UHPC samples (panel/perforated/column): delivered within 7 working days

Guangdong Qinglong Construction Engineering Co., Ltd.

• Address: Room 302, No. 22 Dongming Road, Shiqi District, Zhongshan, Guangdong
• Phone: 13902597531 (Mr. Song)
• Website: qlgrc.com

Author: Song Dunqing (Founder of Qinglong, Senior Engineer, UHPC R&D Lead, 15 years in cement-based composite materials)
Reviewer: Zhang Ke (Qinglong Chief Engineer, NYU Chemistry Master's)
Testing basis: JC/T XXXX-202X, GB/T 50081, GB/T 50082, NT Build 492