This report reviews the literature on continuously reinforced concrete pavement (CRCP). The established analyses, design methods and empirical rules for deciding the minimum area of longitudinal reinforcement in CRCP appear to be both consistent and reasonably good. Where reinforcement failures, or excessively wide cracks, have arisen it has generally been either in older pavements, with lesser steel areas, or at inadequate reinforcement splices. The accepted criteria for deciding what is an acceptable, or desirable, crack pattern are all questionable. In particular, the upper limit on crack spacing does not appear to have any logical basis except by virtue of its correlation with crack width. The average crack spacing, and apparently the crack width, which will develop in CRCP can be predicted reasonably well from existing research. However the present analyses do not predict crack pattern and in particular cluster cracking. These may be due to concrete variation along the pavement, warping or variation in the wheel load stresses due to variation in the sub-base support. Punch-outs are the most important form of structural failure in CRCP. They occur in regions of cluster cracking but not all cluster cracking leads to punch-out failure. Whilst the literature is not clear, it appears likely that the loss of support from the sub-base leads to cluster cracking and punch-outs. Cluster cracking produced by other effects may not give rise to punch-outs. The longitudinal steel in CRCP contributes to its structural behaviour. There is also some evidence that transverse steel could contribute to structural behaviour. Increasing the transverse steel may enable the thickness of the pavement and hence also the quantity of longitudinal steel, to be reduced. However, research is required before this could be tried on a large scale. (A)

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