What Are the Steps in UHPC Exterior Decorative Trim Fabrication — A Detailed Guide to the UHPC Exterior Decorative Trim Production Process and Key Steps

In the field of contemporary architectural decoration, ultra-high performance concrete (UHPC) has become the material of choice for exterior wall decorative moldings thanks to its outstanding mechanical properties and artistic expressiveness. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group will analyze the standardized production process of UHPC exterior wall decorative moldings from a professional perspective, providing designers and owners with a reference guide that combines technical depth and practical value.

1. UHPC Material Mix Design: Dual Assurance of Performance and Formability

The quality foundation of UHPC exterior wall decorative moldings begins with precise material mix design. Based on over a thousand engineering projects, the Qinglong technical team adopts a scientific ratio of quartz sand, cement, steel fibers, and specialized admixtures, achieving a compressive strength exceeding 150MPa and a flexural strength above 25MPa, while maintaining flowability to meet the forming requirements of complex moldings. The introduction of nano-scale silica fume effectively increases the density of the interfacial transition zone, ensuring the durability of the moldings in extreme environments ranging from -40℃ to 70℃. Notably, for different levels of design complexity (e.g., European carved moldings require higher flowability), the water-binder ratio and fiber content must be dynamically adjusted—a step that requires at least 3 rounds of mix verification conducted in a professional laboratory.

2. Mold Fabrication and 3D Detailed Design: Precise Transformation from Drawings to Solid Forms

Mold craftsmanship directly determines the forming precision of decorative moldings. Qinglong uses BIM technology for parametric modeling, combined with 3D scanning reverse engineering, to convert design drawings into digital models with an accuracy of ±0.5mm. For straight standard moldings, steel modular molds are used, allowing more than 300 reuses; curved and irregular moldings use epoxy resin composite molds, with a vacuum infusion process ensuring the faithful reproduction of surface textures. The mold joints feature a mortise-and-tenon structure design, complemented by sealing strips to prevent slurry leakage—a process that raises the forming pass rate to over 98% compared with traditional wooden molds.

3. UHPC Casting and Curing Process: Critical Control of Strength Development

The casting stage requires strict control of concrete workability. Qinglong's proprietary dual-helix mixing process increases the dispersion uniformity of steel fibers by 40%, preventing stress concentration cracks later on. A combined vibrating table and vacuum degassing process ensures concrete compactness reaching 99.2%. The curing stage implements three-stage temperature control: steam curing is initiated within 2 hours after casting (constant temperature of 60℃ for 4 hours), followed by 28 days of standard curing, and finally 7 days of low-temperature water curing, enabling the early strength of components to reach targets quickly while later strength continues to grow steadily. This curing system increases 28-day strength by 20% compared with conventional curing, effectively shortening the production cycle.

4. Surface Treatment and Quality Inspection: Details Determine the Decorative Effect

Formed UHPC moldings must undergo multiple surface treatment procedures: first, mechanical grinding removes flash and burrs; then high-pressure water jets wash away surface dust; finally, fluorocarbon paint spraying or stone-imitation texturing is applied according to design requirements. Qinglong has established a three-level quality inspection system, including: incoming raw material inspection (e.g., steel fiber length deviation ≤5%), in-process inspection (3 test blocks sampled from each mold for flexural strength testing), and finished product inspection (ultrasonic flaw detection for internal defects). Particularly for the installation hole positions of exterior wall moldings, a 3D coordinate measuring machine is used for positional inspection, ensuring on-site installation errors ≤2mm.

As a national high-tech enterprise and a participant in formulating UHPC industry standards, Qinglong Group, with intelligent production lines boasting an annual capacity of 600,000 square meters, has provided customized UHPC decorative molding solutions for hundreds of landmark projects at home and abroad. Full-process control from material R&D to finished product delivery not only guarantees the structural safety and aesthetic effect of the moldings, but also achieves sustainability in architectural decoration. In the future, as UHPC materials see deeper application in the architectural field, the combination of standardized production processes and customized design capabilities will become the core competitiveness for enhancing building quality.