Prevent Thermal Cracking By Monitoring the Temperature of Mass Concrete
According to the American Concrete Institute (ACI), mass concrete refers to large volumes of concrete that require preventative measures to be taken in order to minimize cracking associated with heat generated by the hydration of cement.
Thermal cracking develops when the tensile stress of the concrete exceeds its tensile strength. This leads to various types of cracking, including random map cracks, series of vertical cracks in walls with the widest near the base of the wall, and uniformly spaced cracks in beams. In severe cases, these cracks can affect the integrity of the entire structure.
Ambient temperature, concrete mix temperature, and differential temperature all need to be monitored and adjusted appropriately to avoid thermal cracking.
Tips for Controlling Concrete Temperature
- Optimize your concrete mix. Using low-heat cement; aggregate substitutes such as fly ash, limestone, or slag; and low water-to-cementitious materials are all good ways to optimize your concrete mix.
- Use insulation to control temperature differentials between the core and the surface.
- Cool concrete before placement using chilled water, chipped or shaved ice, or liquid nitrogen.
- Cool concrete after placement by embedding non-corrosive cooling pipes prior to concrete placement. This removes heat by circulating cool water from a nearby source.
However, in order for the implementation of any of these measures to make any valuable difference, you must be able to monitor and report on changing temperature levels. Currently there are a number of temperature monitors in the market for this purpose, including the Doka, the Intellirock, and, of course, the SmartRock2.
SmartRock2: Wireless Concrete Temperature Sensor
Like other temperature monitors currently in the market, the SmartRock2 provides real-time analysis of temperature and strength in all stages of concrete placement. The sensors are embedded into the concrete where they measure, at regular intervals, temperature fluctuations from fresh to hardened stage.
SmartRock2 is by far the most efficient way to monitor the effects of the temperature control measures mentioned above. With this information, you can achieve optimal concrete formulation and temperature curing conditions.
One of the biggest advantages of SmartRock2 is that it is completely wireless. This means you don't have to worry about tripping over messy wires, accidentally cutting the wrong wire, or damaging the sensors at the jobsite. It also means that you have concrete temperature and strength data at your fingertips, using our free SmartRock2 app, available for both iOS and Android.
With SmartRock2, you no longer need a separate costly data logger. Data, along with all of your mix calibrations, is stored in a cloud, where it can be easily accessed by you or your team anywhere, any time. An added plus: software updates are easy and free! Try SmartRock2 for yourself today!