Types of Distress in Concrete Pavements
Concrete is renowned worldwide as one of the most durable and toughest construction materials. To this end, the material is used for outdoor surfaces that will be exposed to heavy foot and vehicular traffic. While this is an excellent choice for your pavements, concrete is in no way infallible. Several issues might cause the failure of your concrete surfaces, the leading one being its distress.
When most contractors get a call from clients for concrete repairs, they immediately reach for concrete patch and other repair products. These might be efficient in some cases, but they are not a one-size-fits-all solution. You should assess the type of distress that has caused the failure of the concrete surface in question before settling on the right repair technique and product for the pavement.
The following are the types of problems commonly seen in concrete pavements.
Cracks in pavements are often caused by the contraction, warping, and expansion of the concrete surface. The loss of subgrade support, improperly or insufficiently cut concrete joints, and overloading are also common causes of concrete cracks. Diagonal, longitudinal, and transverse cracks are a result of combined shrinkage stresses and repeated loads. They indicate weak underlying layers and poor construction techniques.
Corner breaks often arise from load repetition and curling stresses, while durability cracks result from environmental changes such as freeze-thaw changes. The shattered slab is also categorized under cracks and arises from inadequate foundation support and overloading.
This denotes the breaking of a concrete surface into small particles and the dislodging of the resulting aggregate particles. Disintegration generally arises from the improper finishing and curing of concrete, the use of unsuitable aggregates, and an incorrect concrete mix. It can be categorized into scaling, blowups, and corner and joint spalling.
Blowups frequently occur at transverse joints that are not wide enough to allow concrete expansion. Corner spalling happens approximately two feet within a surface’s corners, while scaling is the loss and disintegration of a pavement’s wearing surface.
This denotes a change in the pavement’s original position. It often results from expansive soils, improperly designed drainage systems, and foundation settlement. Distortion generally occurs in the form of faulting or pumping. Pumping is characterized by water and subgrade ejection through a pavement’s joints that causes the progressive loss of supports and eventual cracks. It is caused by poor joint sealing, groundwater presence, and poor joint-load transfer. Faulting or settlement denotes an elevation difference at cracks or joints caused by frost heaves, swelling soils, or a loss of load transfer devices such as the dowel or key.
Loss of Skid Resistance
The skid resistance of concrete denotes the friction characteristics of a concrete surface under different weather conditions. This can be lost due to a decrease in surface texture or accumulation of contaminants such as rubber or oil spills. Naturally polished aggregates will also become skid hazards if used on pavements uncrushed.
Once you understand the above causes of concrete distress, you are better placed to also prevent it. The prevention alternatives for concrete distress include crack overbranding, use of crack infill materials, and water drainage. Once you grasp how to repair and prevent concrete failure with the right tools and products, you are guaranteed of happy clients.