Shotblasting the top surface can introduce additional concerns that can influence the quality of the finished product. Shotblasting can produce a pattern or rows that can be conspicuously visible, especially when coated with a thin mil system. Although these lines will not influence the performance of the coating, they may be unacceptable to the owner from an appearance standpoint and can add unexpected costs in order to correct the problem.
Furthermore, Shotblasting can also cause opening the pores of the concrete. This allows entrapped air to escape more readily, and with the use of a non-breathable coating or topping, the escaping air can make bubbles or craters in the cured coating. To minimize this potential, it may be essential to apply an additional base or prime coat, or by applying the base coat when the concrete and air temperatures are the same, reducing out-gassing from the slab.
Scarifies may be used where thick coating exists or when a very aggressive profile is desired. Scabblers are not suggested except where special circumstances require this type of preparation. The pounding blows delivered by scabblers can cause micro-fissures in concrete that can lead to potential bond failure or delamination under conditions of thermal expansion and/or thermal shock.
Though it is crucial to be aware of these potential problems, keep in mind that abrasive preparation of concrete is still the best means of surface preparation. It is also crucial to note that abrasive preparation alone may not always be enough, in specific
instances BOTH shotblasting and chemical preparation may be necessary.
NOTE: It is always best to contact the manufacturer of the abrasive equipment, the equipment rental dealer, or your surface preparation subcontractor directly for more specific information on the use and capabilities of this type of equipment.
Horizon Epoxy Floor, as a company of many years of experience in this field, has been doing the best to make the customers happy and satisfied. In case you are interested or you have any question we will be highly glad to hear from you.