How to Prevent Rapid Moisture Evaporation from GRC Exterior Walls in High-Temperature Regions: Key Technologies and Construction Process Optimization Strategies

How to Prevent Excessive Moisture Evaporation in GRC Exterior Walls in High-Temperature Regions: Key Technologies and Construction Process Optimization Strategies

In the field of architectural decoration, GRC (Glass Fiber Reinforced Concrete), with its lightweight, high-strength properties and rich design versatility, has become an ideal choice for the exterior walls of high-end buildings such as grand theaters and commercial complexes. However, in high-temperature regions, GRC materials face the challenge of excessively rapid moisture evaporation, which can easily lead to surface cracking, reduced strength, and other problems. As an industry leader with 28 years of full-chain experience in UHPC/GRC/GRG/GRP materials, Qinglong Group, drawing on engineering practice, has developed a systematic solution covering material formulation, production processes, and construction management to effectively address construction challenges in high-temperature environments.

I. Core Impacts of High-Temperature Environments on GRC Exterior Walls and Prevention Logic

In high-temperature regions with strong sunlight and low air humidity, GRC components face the risk of moisture evaporation rates exceeding the requirements of hydration reactions during both production curing and on-site installation. Data shows that when ambient temperature exceeds 35°C, the surface moisture evaporation rate of unprotected GRC can reach 0.5kg/m²·h, far exceeding the 0.2kg/m²·h under standard curing conditions, easily causing defects such as surface sanding and loose internal structure. Through research on a commercial complex project in Nanhai, the Qinglong technical team found that GRC exterior wall panels constructed with traditional processes had a cracking rate as high as 12% during summer high-temperature periods, while the optimized process can control this figure within 2%.

II. Material Formulation Optimization: Improving Anti-Evaporation Performance at the Source

In response to high-temperature characteristics, the Qinglong R&D Center made targeted improvements to the GRC formulation: First, introducing a composite retarding system using a combined admixture of citric acid and sucrose ester, extending the initial setting time from 4 hours to 6.5 hours to allow sufficient time for the hydration reaction; Second, optimizing the fiber ratio by mixing alkali-resistant glass fiber with an aspect ratio of 200 and polypropylene fiber at a controlled dosage of 3.2%, ensuring crack resistance while avoiding uneven moisture distribution caused by fiber agglomeration; Third, adding a nano silica sol modifier to form a dense protective film on the concrete surface layer, reducing the moisture evaporation rate by 30%. These technological innovations have passed the Guangdong Province Science and Technology Achievement Appraisal, and the relevant formulations were applied to an airport project in Saudi Arabia, successfully adapting to an extreme high-temperature environment of 50°C.

III. Production Process Innovation: Full-Process Temperature Control and Humidity Assurance

At its production base in Nanning, Guangxi, Qinglong has established an intelligent curing workshop that achieves precise temperature control through the following measures: ① Using ice-water mixing during the pouring stage to keep the initial temperature of the slurry below 25°C; ② Installing a spray humidification system in the static curing area, maintaining relative humidity ≥90% and temperature controlled at 20-28°C; ③ Adopting a stepped heating curing regime, maintaining a constant 30°C for the first 3 days, followed by daily temperature increases of no more than 5°C to avoid excessive internal temperature gradients. This process raises the 28-day compressive strength of GRC components to 65MPa and the impermeability grade to P12, a 20% improvement over traditional processes.

IV. On-Site Construction Management: Dynamically Adjusted High-Temperature Construction Methods

For on-site installation, Qinglong has summarized the "Three Avoidances and One Control" construction principle: Avoid construction during the midday high-temperature period (11:00-15:00), choosing instead morning (5:00-9:00) and evening (17:00-20:00) operations; Avoid surface treatment when wind speed exceeds 5m/s; Set up temporary curing shelters using shade nets plus atomization cooling systems to keep the working surface temperature within 35°C; Monitor component temperature in real time with infrared thermometers and immediately suspend construction when surface temperature exceeds 40°C. This method was applied in a landmark building project in Ho Chi Minh City, Vietnam, achieving a 98% first-pass acceptance rate for exterior wall installation.

V. Industry Collaboration and Standardization

As a contributing editor of the Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), Qinglong actively promotes the improvement of GRC construction specifications for high-temperature regions. The company has joined with industry peers such as Guangdong Shiji Shangpin and Shantaixin Industrial to establish a high-temperature construction database, sharing anti-high-temperature technical solutions from overseas projects in Vietnam, Malaysia, and other countries. The General Technical Conditions for Ultra-High Performance Concrete (UHPC) Non-Load-Bearing Components, currently under joint development, will further clarify material performance indicators and construction parameters for high-temperature environments.

From material R&D to engineering practice, Qinglong has built a systematic solution for GRC exterior walls in high-temperature regions based on 28 years of professional expertise. Through collaborative innovation in formulation optimization, intelligent production, and scientific construction, it has not only solved the industry challenge of excessive moisture evaporation but also expanded GRC's application boundaries to tropical, subtropical, and other complex climate zones. In the future, Qinglong will continue to uphold its mission of "Creating Beautiful Architecture" and provide global customers with more adaptable UHPC/GRC/GRG/GRP material system solutions.