It is also important to be aware of what type of pavement one is repairing.
Jointed Concrete Pavement (JCP) is designed to expand and contract between each panel of the pavement. Repairs need to be made to allow that movement of the pavement to remain. If repairs are made that bind that movement, the result will be a repair that is likely to fail. If the base is failed below the pavement, the loose base needs to be removed and replaced with a suitable compacted material that allows the repaired concrete to expand in a
manner that is unbound.
With Continuously Reinforced Concrete Pavement (CRCP), the forces of nature that cause the roadway to expand or contract result in a pavement that, by design, cracks yet remains long-lasting and durable. Inevitably, even long-lasting CRCP will need repair. It is important to understand that CRCP develops cracks within concrete to handle the forces of nature. It is designed as a bound system. Repair of a failed base may be best served in an unconventional manner. It is understandable that it would be reasonable to replace a failed base supporting a concrete pavement with the same materials that were used for the original construction. However, it has been observed that the textbook solution for the base repair may not be the best solution to the problem. Of course, all loose road base should be removed, but it may not be necessary to replace that base in the same manner it was originally placed, as it may not be practical given the conditions. Please let me explain.
CRCP is generally placed for use in high-traffic conditions. When it needs repair, that work is generally performed at night to minimize the impact on traffic. However, working at night limits the availability of materials for use. Concrete for night work is generally supplied by a smaller concrete plant established for the repair work or a volumetric truck. Hot Mix Asphalt (HMA) or Cement Treated Base (CTB) could be used for base, but those operations are generally not cost-effective for smaller nighttime operations like concrete repair. Asphalt millings, untreated base, or soil could be used, but these materials have been found to be insufficient to provide adequate support for the concrete repair work.
Because of the nature of CRCP being bound tightly, it has been observed that using concrete to fill the repair area below the reinforced concrete area has been a reliable and best practice. The extra depth concrete provides a better base for the limited concrete repair areas. The extra depth better supports the concrete pavement and also reduces the time of construction, which is all so important to nighttime work and lanes need to be reopened before the morning commute, and repairs have been found to be long-lasting.
Additionally, if concrete repair is needed for CRCP that has been overlaid with asphalt, extra depth concrete to the top of the repair area has been found to be reliable, as it is difficult and not cost-effective to provide asphalt at night or for limited operations. If maintenance to the surface is needed, the unreinforced extra height portions can be handled with modern milling equipment.
Repairs often fail when the rebar replacement is faulty. It is important that the rebar dowelled for the repaired section be drilled to the proper length and epoxied correctly as prescribed by TxDOT specifications. TxDOT has spent considerable effort recognizing that failure of repairs has been directly linked, in many cases, to simply not following the correct epoxying procedures. Do not allow any method that deviates from the specification.
Concrete pavement repair is paid for by the square yard, but it is more important to sawcut a reasonable amount beyond the limits of the visible damage. Half lane repairs are allowed, but full lane repairs have been observed to be more durable.
Successful concrete pavement repair balances precision with practicality. Making repairs correctly—while simplifying construction operations—helps ensure lanes can reopen on time and perform reliably for years to come.