Procedures for permanently patching and for pressure grouting of continuously reinforced concrete pavement have been developed. These procedures have been extensively field tested to ensure their practicality and adequacy. The patching procedures reduce costs and lane closure time by considering the different distress types, different methods of construction, and concrete additive and curing for early opening. The pressure grouting procedures provide for a restoration of support beneath the slab and the prevention of future pumping.

The performance of CRCP has revealed a number of failure modes that are traceable to design, construction, materials, and maintenance deficiencies and such other factors as environemntal conditions and traffic loadings. This report of the Transportation Research Board includes a review of the cumulative experiences of state that have constructed and maintained CRCP. Guidelines for repair techniques are included, and areas of needed research are identified.

This report details the results of an in-depth study of methods and costs of repairing failures in continuously reinforced concrete pavement. The study was conducted in 1977 by teams of Engineers from four States: Arkansas, Louisiana, Mississippi, and Texas. Similarities were revealed in the methods of repair used by maintenance personnel in the four States. Subtle differences were also discovered which can be considered for implementation by all of the participants and others to improve their maintenance techniques.

Procedures for permanently patching and for pressure grouting of continuously reinforced concrete pavement have been developed. These procedures have been extensively field tested to ensure their practicality and adequacy. The patching procedures reduce costs and lane closure time by considering the different distress types, different methods of construction, and concrete additive and curing for early opening. The pressure grouting procedures provide for a restoration of support beneath the slab and the prevention of future pumping.

A study of the performance of Continuously Reinforced Concrete Pavement (CRCP) constructed on the Interstate highway system in Illinois has-been conducted. The major purpose is to determine the types, severities, amounts, and causes of distress. This information will then be used to develop optimum maintenance procedures to repair the distress that occurs, and preventative maintenance procedures to reduce the rate of distress occurrence. The distress data collected can also be used to update CRCP design procedures. Approximately 1230 miles of Interstate highway was surveyed, consisting of 7 to 10 in. (17-25 cm) slabs over granular and stabilized subbases. Distress found includes edge punchouts, steel ruptures, "D" cracking, blowups, construction joint failures, lug rotation, longitudinal cracking, distress related to construction problems, pumping, and shoulder deterioration. Heavy truck loads, excess free moisture, deicing salts, construction practice and poor aggregate quality in the CRCP slab are the major factors causing distress. CRCP slab thickness and foundation support have a very significant effect on structural distress development. "D" cracking is causing severe deterioration of several projects. Overall, the performance of the thicker CRCP slabs (i.e., 9-10 in.) has been very good under heavy truck traffic; however, the performance of many sections of thinner CRCP (i.e., 7-8 in.) has been poor, and is showing an accelerated rate of distress development over time. The amount of distress expected to occur, and the maintenance effort required in the next several years points strongly toward a need for the development of more efficient and durable ways of maintaining CRCP.

This aim of this handbook is to assist U.S. Federal Highway Administration area engineers when they make highway construction inspections. It can also be used when reviewing specifications, supplemental specifications, and special provisions during the PS & E stage of a project. Information contained herein is a guide and is not intended as a standard. The number of different rehabilitation techniques covered in this handbook are limited at this time. Additional construction techniques for rehabilitating rigid and flexible pavements will be added and the handbook expanded at a later date.