Concrete may look simple on site, but temperature conveys otherwise. After cement begins to hydrate heat is generated within the mixture. In thin slabs, that heat may escape without too much hassle. The internal heat of dams, foundations, bridge piers, power plants and tunnels surrounded by tons of concrete can remain 'trapped' for days in case of mass pours. As your surface cools more rapidly than the core (if the heat from melted metal relatively early in the process like some of ours) thermal stress increases and cracks can actually happen before a structure is ever put into service!
This is precisely why, temperature control in concrete construction is but not a minor technical detail. Quality control, schedule control, risk management — these all go here. At large scale projects, contractors generally require a concrete cooling unit upstream from the actual area of pour.
Focusun present integrated Concrete Cooling solution for projects where accurate temperature control during bating, mixing, delivering and placing of concrete is required.
The workability, setting time, hydration rate, strength development and long-term durability of fresh concrete temperature. Concrete can arrive on site close to these limits in hot climates, or during low volume pours. Internally, heat of hydration(s) further raise the temperature after placement.
It is not only the “hot concrete” risk. The other, larger problem is temperature gradient. When the inside of a large structure remains warm and the surface cools, it expands and contracts unevenly. That difference creates tensile stress. If that stress exceeds the initial strength of the concrete, cracks are formed in those regions.
An appropriate cooling scheme minimizes the placing temperature, limits internal maximum temperature and reduces the difference between interior and surface temperatures. This is particularly true for mass concrete, marine structures, dams, high-rise foundations, subway projects and nuclear facilities as well as infrastructure built in hot or very hot weather.
One size does not fit all when it comes to how you approach a project. Adding night placement, shaded aggregates, or cooler mixing water may make a small pour only. Typically you need a whole bunch of methods in combination for a big infrastructure job.
The most common concrete cooling methods are: Chilled mixing water, Flake ice put directly into the mixer, Aggregate Cooling insulated Ice storage, Automatic conveying of flake ice, Accurate weighing of added ice and Post-cooling pipes when required by design. At the heart of Focusun Concrete Cooling System are these connected modules, including water chilling module, ice make module, ice storage and delivery module, ice dosing system and automatic control.
Cooling component Chilled water is typically the first stage of concrete temperature control. Instead, it uses water cooled via an industrial chiller instead of regular mixing water. This helps to alleviate the temperature of concrete without modifying the basic batching process.
Focusun is an alternative for Water Chiller screw-type water-cooled and air-cooled chillers. For concrete plants, this chiller is connected typically with cold water tank and pumping station. This configuration maintains chilled water on-demand for consistency in batching—even during the busiest production spikes throughout the day.
For mid-level cooling, merely chilled water might be sufficient. In highly ambient temperature or when a strict placing temperature is desired, flake ice is frequently added to chilled water.
Flake ice is one of the most used equipment’s here. This property yields a substantial contact territory, entirely can melt in the blender using small bit of moment, and ingests heat promptly out of cement materials. Flake ice is easier to dose, convey and mix compared with block ice that must first be crushed.
The Flake Ice Machine series of Focusun includes different daily production capacity from a few hundred kilograms to several tons Industrial flake ice plant. At a concrete plant, ice machine matching will include insulated storage and screw conveyors, pneumatic delivery or belt conveying as site layout requires.
Consistency is Critically Important to Produce Mass Concrete Using Ice: In Continuous Production It has to make enough ice; store it with minimal melting loss, and dispense the correct quantity into each batch. This is why the ice storage and weighing system should be jointly designed with the batching plant rather than treated as a separate accessory.
And creating ice is not the full job. If the ice cannot be stored, moved, and compactly weighed accurately, the cooling result will be unstable. A fully integrated system for cooling of concrete usually consists of an insulated bin for ice storage, automatic containment ice filling, discharging equipment, distribution conveying lines, and units that weigh.
The Concrete Refrigeration can be constructed for horizontal or vertical delivery. Depending on distance, height, batching plant position and site space, delivery may be by spiral conveying or pneumatic conveyor (or mixed).
As ice displaces a portion of the mixing water, accurate dosing is vital. System must also match mix design and avoid random water addition Effective cooling requires keeping the dosing to a minimum, otherwise the curing of concrete consistency can be negatively impacted.
In construction, concrete temperature control is usually classified into pre-cooling and post-cooling. Pre-cooling happens before placement. It uses chilled water, ice, aggregate cooling or other means to lower the temperature of the materials or the fresh concrete.
Post-cooling happens after placement. Expandable cooling pipes consisting of individual piping systems can be incorporated in the concrete to allow chilled water to flow through the structure and remove internal heat. Some large dams, foundations or sections of thick concrete need to maintain the temperature within something like a predetermined range for a longer time, from days to about 28 days; this method is used in them.
Pre-cooling is the primary method used in many projects since it directly reduces the placing temperature. In the case of very large structures, pre-cooling and post-cooling can be administered together on a temperature monitoring plan.
Prior to any purchase of equipment, the project team should first establish: concrete placing temperature (target), hourly output volume, cement amount, aggregate temperature, water temperature, ambient condition using trial mixes; batching cycle(s) for the desired production rate; available power and site layout; delivery distance from cooling plant to mixer etc.
Cooling System vs. A cooling system for a ready-mix plant is not synonymous with that of a dam project Temporary infrastructure sites are probably more suited to a mobile or containerized design, and fixed plant will suit long-term production. Daily volume of concrete, the degree of temperature drop required, working hours and accessible for maintenance all determine the right design;
Focusun will evaluate the project situation and suggest the system that combines chillers, ice machines, storage, conveying and weighing equipment. You may also reach out to the team via Contact US for project based assessment.
Focusun Refrigeration specializes in industrial ice makers and refrigeration equipment. This background is relevant for concrete cooling because a mechanic add-on just will not fit, this is connected to refrigerating project with additive construction production relations.
An appropriate supplier should be knowledgeable of heat load, ice capacity, water flow, automation and DIY service installations. Building more than 200 systems, Focusun can create a solution tuned to local climate, concrete output, site arrangement and temperature target. Visit Us — Learn more about the company on the About Us page.
Making the cooling system an integral part of the construction workflow system instead of treating it as a remedial measure when concrete temperature control is communicated and planned early. This leads to the more predictable batching, reduced risk of thermal cracking and better control over quality of large-volume concrete.
In construction, concrete temperature control is the means of managing either hot or cold conditions in fresh and hardening concrete to minimize thermal stress/control setting time and prevent cracking It has specific applications for mass concrete, hot-weather concreting, dams, bridge piers and other large slabs or infrastructure projects.
Why does concrete get hot? Because the hydration of cement gives off heat. The pattern repeats for areas in concrete — this is fairly large and heat cannot escape quickly so the internal temperature rises. As it cools, if the surface loses heat faster than the core, stresses will arise and cracks will form.
The optimal approach depends on how much cooler your shots need to be. Cooling methods may include chilled mixing water, flake ice, aggregate cooling, shaded material storage and night batching to name a few. Most of such large projects use a mixture of chilled water and flake ice, which maintains the stability of concrete temperature.
Flake ice is directly introduced into the mixer, it substitutes a part of the mixing water. While melting, it takes heat from concrete materials. The thin shape and expansive surface area help to produce a fast-melting element that cools the mixture uniformly.
For moderate cooling loads, in first stages you can do with chilled water (ambient temperatures not extreme). For stricter placing temperature requirements or very hot environments, chilled water is commonly mixed with flake ice in order to achieve a larger temperature reduction.
A full system can contain water chillers, chilled water tanks, flake ice machines, insulated ice storage, ice conveying equipment, ice weighing units, pumps controls and sometimes aggregate cooling or post-cooling systems.
Temperature monitoring is recommended for mass concrete, critical foundations, bridge piers, dams and specifications with strict thermal control requirements. Sensors allow engineers to monitor core and surface temperatures so they can optimize curing, insulation, or cooling steps.
One method of hindering thermal cracking in concrete is to reduce the placing temperature, which will decrease the peak internal heat of hydration. While it is an important control measure you cannot replace good mix design, curing, reinforcement or construction practice.
A supplier capable of calculating cooling demand, matching equipment to batching capacity, designing ice storage and delivery solutions, and tailoring the system to fit your site layout should be selected. Refrigeration, ice making, automation and construction conditions.
