Reasons for cracking and damage of hydraulic bricks

If the quality of hydraulic bricks is not good enough, cracks will appear. Cracks mainly occur during the baking stage, and various stresses are generated during baking. If the stress exceeds the allowable strength of refractory materials, cracks will occur. Let's take a look at several reasons for crack formation.
1. Surface cracks are constrained by the nonlinear temperature field of hydraulic bricks themselves, or caused by sudden drops in temperature, resulting in large concrete surfaces and steep temperature gradients. Surface cold concrete is constrained by internal hot concrete, resulting in temperature stress. When the temperature stress exceeds the tensile strength of concrete of the same age, surface cracks will occur. If not affected by other factors, it usually forms through cracks or deep cracks.
2. Due to the high pouring temperature of concrete, the hydration heat of concrete increases, resulting in a higher temperature of concrete. When the temperature drops to a lower level during the construction period or a stable temperature during operation, a basic temperature difference will occur. This uniform condensation generates temperature stress that runs through the entire cross-section, and when it exceeds the tensile strength of concrete of the same age, it will produce through cracks. It can be seen that surface cracks are caused by self constrained deformation (internal concrete), while surface penetrating cracks are caused by external constrained deformation (foundation or old concrete).
3. Temperature difference stress: During baking, there is a certain temperature difference inside the brick, which generates stress.
4. Mechanical stress: Excessive mechanical load on the brick causes non elastic deformation of the hydraulic brick, leading to damage.
5. Crystal transformation stress: Bricks will undergo crystal transformation during the heating process. If the crystal changes too quickly and generates too much stress, hydraulic bricks may also crack.
The above content is an introduction to the causes of cracks in hydraulic bricks. During the production process, it is important to pay attention to these issues to ensure the quality of brick production. If you have any other questions about the product, please contact us. We look forward to working with you.