Analysis of Material Requirements and Selection Standards for Embedments Used in UHPC Component Installation

In the installation of ultra-high performance concrete (UHPC) components, embedded parts serve as the core nodes connecting components to the main structure, and their material selection directly affects building safety and durability. As an industry-leading enterprise with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group combines detailed design, manufacturing, and construction practice to provide an in-depth analysis of embedded part material requirements and selection criteria, offering professional solutions for designers and owners.

### Baseline Material Performance Requirements for Embedded Parts in UHPC Components

UHPC materials are renowned for their ultra-high strength (compressive strength ≥150MPa), excellent durability, and toughness, and their embedded parts must meet three core performance indicators. The first is mechanical strength compatibility: the tensile strength of embedded parts should be no less than 500MPa, with yield strength ≥345MPa, to withstand the composite stresses generated by the self-weight of UHPC components as well as wind loads and seismic action. The second is weather resistance: in humid, saline-alkali, or high-temperature environments, embedded parts must possess corrosion resistance—for example, when hot-dip galvanizing is used, the zinc layer thickness should be ≥85μm, or stainless steel materials (such as 316L) should be selected to ensure a service life of over 50 years. In addition, weldability and machining precision of the material are also crucial: the welded joint strength of embedded parts must exceed that of the base material, and dimensional deviations must be controlled within ±1mm to ensure precise fit with UHPC components.

### Technical Characteristics Comparison of Four Major Categories of Embedded Part Materials

Embedded part materials commonly used in current building engineering mainly include carbon structural steel, low-alloy high-strength steel, stainless steel, and composite anti-corrosion steel. Carbon structural steel (such as Q235B) is relatively low in cost but requires strict surface anti-corrosion treatment to be suitable for dry indoor environments; low-alloy high-strength steel (such as Q355ND) offers 40% higher strength and, combined with epoxy resin coating, can be used in moderately corrosive environments, making it the mainstream choice for UHPC curtain wall components. Although stainless steel (304/316) has a higher initial cost, its chromium-nickel alloy forms a passive film and performs excellently in highly corrosive environments such as coastal areas and chemical plants, with a typical application being the UHPC sunshade system of a waterfront landmark project in Guangzhou. Composite anti-corrosion steel (such as zinc-aluminum-magnesium alloy coated steel), through the synergistic effect of metallic coatings and organic coatings, achieves salt spray resistance of over 5,000 hours, offers significant cost-effectiveness advantages, and has been successfully applied in multiple municipal projects undertaken by Qinglong.

### Engineering Scenario-Oriented Selection Criteria System for Embedded Parts

The selection of embedded part materials must be based on engineering scenario analysis, forming a three-dimensional decision model of "environment-load-cost." For super high-rise UHPC exterior wall panels, Q355ND low-alloy steel with hot-dip galvanizing plus sealing paint treatment should be prioritized to ensure structural safety under wind loads; garden landscape UHPC components (such as benches and planters) can use Q235B carbon steel with cathodic protection measures to balance economy and durability. For overseas projects, such as the Southeast Asian airport project undertaken by Qinglong's Malaysia branch, 316L stainless steel should be selected based on local climate parameters to cope with hot, humid marine atmospheric environments. It is worth noting that the interfacial bond performance between embedded parts and UHPC must be verified through pull-out tests, with bond strength ≥3MPa, which requires sandblasting roughening treatment of the embedded part surface to increase contact area and mechanical interlocking force.

### Full-Chain Quality Control and Industry Standard Practices

As a participating editor of the industry standard "General Technical Conditions for Non-Load-Bearing Ultra-High Performance Concrete (UHPC) Components," Qinglong Group has established a full-process quality control system from material selection to finished product inspection. Raw materials entering the site must be accompanied by material certificates and third-party test reports, with focused verification of carbon equivalent (≤0.45%) and phosphorus-sulfur content (≤0.035%); in production, CNC machining ensures the geometric precision of embedded parts, and 100% ultrasonic flaw detection is performed on critical parts; before construction, BIM technology simulates embedded part positioning, and after installation, on-site pull-out tests are conducted with one sample group per 500 pieces, with test values required to be 1.2 times higher than design values. This rigorous quality control has enabled zero-accident operation of UHPC component embedded parts in projects undertaken by Qinglong, such as the Nanjing East Road Century Plaza renovation project, fully confirming the importance of scientific material selection and standardized construction.

Although embedded parts are a "concealed works" element of the UHPC component system, they are key to ensuring building safety. With 28 years of technical accumulation, Qinglong Group deeply integrates materials science with engineering practice, providing reliable embedded part solutions for UHPC component installation through material performance analysis, scenario-based selection, and full-chain quality control. In the future, as UHPC materials gain wider application in the building field, embedded part material selection will place greater emphasis on green environmental protection and intelligent technologies. Qinglong will continue to promote the innovative application of new composite materials in the field of embedded parts, supporting the realization of its corporate mission of "Creating Beautiful Architecture."