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The objective of this study was to identify and quantify design and construction features most important to joint faulting of joint plain concrete pavements. With data obtained from the Long-Term Pavement Performance (LTPP) database, an analysis approach that combined pavement engineering expertise and modern data analysis techniques was to develop guidelines for improved design and construction of Portland cement concrete (PCC) pavement. The approach included typical preliminary analyses, but emphasis was placed on using a series of multivariate data analysis techniques. Discriminant analysis was used to develop models that classify individual pavement into performance groups developed by cluster analysis, which was used to partition the pavements into three distinct groups representing good, normal, and poor performance. These models can be used to classify and evaluate additional or new pavements performance throughout the pavement's design life. To quantify the levels of the key design and construction features that contribute to performance, the classification and regression tree procedure was used to develop tree-based models for performance measure. The analysis approach described was used to develop the guideline on the key design and construction features that can be used by designers to decrease joint faulting of jointed plain concrete pavements (JPCPs).Key words: faulting, Long-Term Pavement Performance (LTPP), jointed plain concrete pavement (JPCP), cluster analysis, discriminant analysis, classification and regression tree (CART) analysis.

The primary objective of the present study is to assess the use of the maturity method to determine the joint sawing window and the traffic opening time on whitetopping construction in Korea. To determine the joint sawing time, it is necessary to determine the minimum strength not to have raveling and to identify the safe time of drying shrinkage. The present study found that the minimum compressive strength for joint sawing was 4.41 MPa (45 kg/cm2) and drying shrinkage occurred just after the concrete temperature peaked. The Nurse-Saul function was used for determining the joint sawing window and the traffic opening time because it better predicted in-place strength. The present study determined that the joint sawing window ranged from 210 °C·h to 310 °C·h (actual time of 6.5 to 9 h) and that the traffic opening time was after maturity values reached 390 °C·h for the mix at 20 °C.

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