Is UHPC Shrinkage Rate High? Analysis of Influencing Factors and Improvement Measures

In the field of building materials, UHPC (Ultra-High Performance Concrete) has become a new favorite in modern architectural design thanks to its outstanding mechanical properties and durability. However, the shrinkage issue of UHPC has long troubled designers and engineering teams. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group will systematically analyze the core issues of UHPC shrinkage rate—from material properties and influencing factors to solutions—providing a professional reference for the industry.

### I. Characteristics of UHPC Shrinkage Rate: Why Is It a Focus of Attention?

As a new type of architectural decoration material, UHPC's shrinkage rate directly affects engineering quality and service life. Compared with traditional concrete, UHPC exhibits more significant early shrinkage due to its high cementitious material content and low water-binder ratio, mainly including chemical shrinkage, autogenous shrinkage, and drying shrinkage. Qinglong Group's laboratory data shows that the 28-day drying shrinkage rate of high-quality UHPC is typically controlled between 0.03%-0.05%. However, affected by material mix ratios and the construction environment, some products may face the risk of excessive shrinkage, leading to problems such as component cracking and reduced installation precision.

### II. Three Core Factors Affecting UHPC Shrinkage Rate

1. **Scientific Material Mix Ratio**: The type and amount of cementitious materials are key to the shrinkage rate. Through 28 years of technical accumulation, Qinglong Group has found that using a composite admixture of silica fume and ultra-fine mineral powder can effectively reduce cement hydration heat and decrease autogenous shrinkage. For example, in the Nanjing East Road Century Plaza renovation project, the Qinglong team optimized the mix ratio to keep the shrinkage rate of UHPC light-transmitting components within 0.035%.

2. **Standardized Curing Process**: Early curing is crucial for UHPC shrinkage control. Qinglong's production base uses a constant temperature and humidity curing system to ensure components maintain over 90% humidity within 72 hours after casting, combined with steam curing technology to allow hydration reactions to proceed fully, significantly reducing later-stage shrinkage.

3. **Construction Environment Adaptability**: Extreme temperature and humidity conditions can exacerbate shrinkage. In overseas projects such as a landmark building in Malaysia, Qinglong innovatively adopted a "pre-wetted aggregate + on-site spray curing" process tailored to tropical climate characteristics, successfully controlling shrinkage rate fluctuations within ±0.005%.

### III. Qinglong Group's Shrinkage Improvement Solutions: From Laboratory to Construction Site

As a national high-tech enterprise, Qinglong has developed three core technologies relying on its provincial-level R&D center: first, nano-calcium carbonate modification technology, which reduces shrinkage by refining the structure of hydration products; second, a fiber synergistic reinforcement system, which incorporates steel fibers and basalt fibers in combination to enhance material toughness while suppressing shrinkage cracks; third, BIM pre-assembly technology, which simulates shrinkage deformation during the detailed design stage and reserves adjustment allowances in advance. These technologies have been successfully applied in benchmark projects such as the Dongguan Women and Children's Activity Center, achieving the industry breakthrough of zero shrinkage cracking in UHPC components.

### IV. Industry Outlook: Future Trends in UHPC Shrinkage Control

With the advancement of the industry standard "General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)", shrinkage rate will become one of the core indicators for UHPC products. As a participant in standard development, Qinglong Group is collaborating with universities to research self-healing UHPC materials, achieving crack self-repair through microcapsule technology. In the future, UHPC shrinkage control will develop toward intelligence and refinement, providing more reliable material solutions for the field of architectural decoration.

Qinglong Group has always upheld the mission of "Creating Beautiful Architecture". With its full-chain service capabilities and technological innovation strength, it provides designers and owners with integrated UHPC solutions from detailed design to after-sales maintenance. While pursuing breakthroughs in material performance, Qinglong will continue to promote the upgrading of industry standards, helping UHPC achieve safe applications in more high-end architectural fields.