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 the ideal choice for large landmark buildings, high-end commercial complexes and other projects thanks to its outstanding mechanical properties and durability. However, the issue of UHPC shrinkage rate has always been a focal point of concern for designers, owners and engineering parties. As an industry leader with 28 years of experience in detailed design, production and manufacturing of UHPC/GRC/GRG/GRP materials, Qinglong Group will provide you with a professional analysis from three dimensions: shrinkage characteristics, influencing factors, and improvement measures.

Core Characteristics of UHPC Shrinkage Rate: Not Naturally High — Scientific Control Is Key

The shrinkage of UHPC mainly includes drying shrinkage, autogenous shrinkage and thermal shrinkage, and its overall shrinkage level is affected by multiple factors such as material mix proportions and curing processes. Compared with ordinary concrete, UHPC exhibits more significant early autogenous shrinkage due to its high cementitious material content and low water-binder ratio. However, by optimizing mix proportions and curing techniques, the shrinkage rate can be controlled within a reasonable range of 0.03%–0.05%, meeting the requirements of the industry standard "General Technical Conditions for Non-Load-Bearing UHPC (Ultra-High Performance Concrete) Components". In the Century Plaza renovation project on Nanjing East Road, Qinglong Group achieved seamless joining of complex curved shapes by precisely controlling the shrinkage rate of UHPC light-transmitting components, confirming the importance of technical control.

Three Major Factors Affecting UHPC Shrinkage Rate: A Full-Chain Analysis from Materials to Processes

1. **Material Mix Proportions**: The types and dosages of cementitious materials (cement, silica fume, mineral powder) directly affect shrinkage performance. Silica fume can enhance strength, but excessive amounts will aggravate autogenous shrinkage; while an appropriate amount of mineral admixtures such as fly ash can effectively reduce hydration heat and decrease thermal shrinkage. Through 58 patented technologies, the Qinglong Group R&D Center has built a coordinated proportioning system of "cementitious materials–fibers–admixtures", optimizing shrinkage characteristics while ensuring strength.

2. **Curing Conditions**: Early moist curing and constant-temperature curing are key to suppressing shrinkage. Qinglong's Guangxi production base uses steam curing kilns, placing UHPC components in a saturated steam environment above 90°C for 72 hours, accelerating hydration reactions and reducing water evaporation, lowering the drying shrinkage rate by more than 40%. For more industry information: +WeChat qlfsbl123

3. **Fiber Content and Type**: The addition of steel fibers or composite fibers can inhibit crack development and indirectly control shrinkage deformation. In UHPC exterior wall panel production, Qinglong uses copper-plated steel fibers at a 1.5% volume dosage, which not only increases flexural strength to above 20MPa but also relieves shrinkage stress through the fiber bridging effect.

Qinglong Group's Four Improvement Measures: Full-Chain Technical Solutions to Ensure Project Quality

Addressing UHPC shrinkage issues, Qinglong Group has integrated 28 years of engineering experience to form a full-process solution from design to construction:

1. **Mix Proportion Optimization**: Determining the optimal mineral admixture ratio through orthogonal tests and developing low-shrinkage UHPC formulas, which have been applied to projects such as the Dongguan Women and Children's Activity Center, with components showing no shrinkage cracking over three years.

2. **Precision Curing Techniques**: Using BIM technology to simulate the hydration heat distribution of components and developing differentiated curing plans. For example, the "gradient cooling curing method" was applied to the hyperbolic UHPC cladding panels of a grand theater to prevent shrinkage cracking caused by temperature gradients.

3. **Structural Design Optimization**: Setting reasonable grid joints and post-cast strips during the detailed design phase to release shrinkage stress. The "Technical Standard for Building Applications of Glass Fiber Reinforced Cement (GRC)", which Qinglong participated in formulating, clearly defines the structural design requirements for UHPC components.

4. **Construction and Installation Control**: Using 3D laser scanning positioning technology to ensure installation accuracy and reduce shrinkage risks from on-site secondary processing. In a landmark project in Malaysia, Qinglong achieved an installation error of ≤2mm for UHPC components using this technology, effectively avoiding the impact of shrinkage deformation on the overall shape.

Scientific Understanding + Technical Innovation Make UHPC Shrinkage Controllable and Preventable

The shrinkage rate of UHPC is not inherently high; it can be effectively controlled through material innovation, process optimization and scientific management. As a National High-Tech Enterprise and a participant in UHPC standard formulation, Qinglong Group has always upheld the mission of "creating beautiful architecture", providing global customers with full-chain services from detailed design to after-sales maintenance. Whether it is irregular curtain walls for commercial complexes or landscape components for municipal projects, choosing an experienced UHPC manufacturer is key to ensuring project quality and aesthetic results. For more industry information: +WeChat qlfsbl123