Liquid Temperature Control in the Construction Industry

Authored by: Dr. Dirk Frese, VP of Sales, Marketing & Service

The most widely used material in construction is cement, which forms concrete when mixed with rocks and other materials. The global production of these materials reaches approximately 4,000 megatons annually. Only water is consumed in greater quantities by humanity.

Still, research is needed to fully understand the process of cement formation. Simply put, cement is created by heating calcium carbonates (limestone), often mixed with clay, to produce calcium oxides (lime), which, together with silicon oxides, form di- and tricalcium silicates.

During heating to 1450 °C and sometimes briefly to 1800 °C, the carbonates lose CO2, which is critical for enriching Carbon dioxide in the atmosphere, which we nowadays are trying to limit and reduce. The production of 1000kg of Portland cement (a hydraulic cement), for example, sets free 900kg of CO2.[1]

In the binding and setting process, water is required to form calcium silicate hydrates, which give concrete the immense strength needed for bridges, buildings, and more. This process, called hydration, is exothermic and requires proper temperature and humidity control.

In 2023, COP28 (the United Nations Climate Change Conference) was held in Dubai and set the goal of achieving zero-emission cement production by 2030, which is a huge task. This is one of the reasons why research and development in the cement industry is thriving and why proper temperature control equipment is essential.

Temperature Control — The Game Changer in Construction

Temperature control is a game-changer in the construction industry, especially in the research and development (R&D) of materials like concrete, cement, and composites. JULABO circulators provide precise thermal management to simulate real-world conditions, ensuring that materials meet performance and durability standards. Below, we delve into specific applications and recommend JULABO models tailored for these tasks.

1. Concrete Curing and Strength Testing

Proper concrete curing is essential to achieve the desired strength and durability. Temperature-controlled baths simulate curing conditions for accelerated or real-time testing.

Recommended Models:

CORIO C Heating Circulators: Ideal for maintaining stable temperatures up to +150 °C, suitable for curing studies in smaller samples.

VALEGRO 350 or 500 with natural refrigerants: Great for maintaining a consistent temperature in curing concrete cylinders or beams for strength testing as well as early-age strength tests, 3, 7, and 14 days after mixing. The temperature range is -20 °C to +40 °C.

MAGIO MS 1000FF Ultra-Low Refrigerated Circulators: For simulating freeze-thaw cycles ranging from -90 °C to +100 °C. This MAGIO variant uses R290, a natural refrigerant with a very low global warming potential of 2.

2. Freeze-Thaw Durability Tests

Concrete and road materials are subjected to cyclic freezing and thawing to assess their resistance to cracking and degradation.

Recommended Models:

MAGIO MS 1000FF Ultra-Low Refrigerated-Heating Circulator: With a working range of -90 °C to +10 0°C, this model is perfect for extreme freeze-thaw simulations.

DYNEO DD Refrigerated/Heating Circulators: Covering temperatures from -50 °C to +200 °C, these units are versatile options for freeze-thaw testing in various conditions.

VALEGRO 350 or 500 Refrigerated/Heating Circulators with natural refrigerants: Covering temperatures from -20 °C to +40 °C, these are versatile options for freeze-thaw testing in durability studies.

3. Thermal Expansion Testing

Construction materials like cement composites are tested for thermal expansion under controlled heating conditions to evaluate their performance under temperature fluctuations.

Recommended Models:

MAGIO Heating Circulators: Offering precise control up to +200 °C, these models are excellent for high-temperature material testing.

PRESTO W50 Circulator: For rapid heating rates and high-temperature stress tests up to +250 °C.

4. Admixture Reaction Studies

Chemical admixtures used in concrete require precise temperature control during R&D to ensure optimal performance.

Recommended Models:

CORIO CD Open Heating Bath Circulators: These models allow internal testing with transparent bath tanks, which is ideal for observing chemical reactions directly.

PRESTO A45 Temperature Control System: This model provides stability for sensitive chemical experiments with a range of -45 °C to +250 °C.

5. Insulation Material Testing

Testing insulation materials involves evaluating their thermal properties through controlled heating and cooling cycles.

Recommended Models:

DYNEO DD Refrigerated/Heating Circulators: Flexible for both heating and cooling applications between -50 °C and +200 °C.

MAGIO MS Refrigerated Circulators: Offering enhanced pump capacity for external systems requiring precise thermal control.

6. Cement Hydration Studies

Precise temperature control is useful for studying the heat of hydration and its effects on early-stage concrete characteristics.

Recommended Models:

VALEGRO 350 or 500 with a temperature range of -20 °C to +40 °C using natural refrigerants.

7. Air Content Testing

Maintaining a constant temperature for fresh concrete during air content testing ensures accurate results across various ambient conditions.

Recommended Models:

VALEGRO 350 or 500 with a temperature range of -20 °C to +40 °C utilizing natural refrigerants.

JULABO Model Features Tailored for Construction R&D:

Why Choose JULABO?

Precision Across Ranges: JULABO circulators offer temperature stability of ±0.01 °C, ensuring repeatable results in R&D applications.

Versatility: Models like the MAGIO and DYNEO series cater to a broad spectrum of temperatures (-90 °C to +250 °C), making them suitable for diverse construction material tests.

Durability and Efficiency: Designed with robust materials like stainless steel tanks and energy-efficient cooling systems for long-term use.

Flexible Fluid Options: JULABO offers a wide range of products with natural refrigerants as well as synthetic refrigerants tailored to your needs.

By integrating JULABO circulators into construction R&D workflows, engineers can precisely simulate real-world conditions, accelerating innovation in road building, bridge construction, and sustainable housing projects. These advanced tools empower researchers to develop stronger, more durable materials that meet the demands of modern infrastructure.

[1] An alternative to this process is non-hydraulic cement, which binds without water. It uses CO2 from air to bind. This article focuses on the main process, which is around hydraulic cement.