Use of Profile Data to Detect Concrete Paving Problems

The ride quality of a pavement is extremely important to road users. Research has shown that pavements that are built smoother provide a longer service life. Because of these benefits, highway agencies have implemented smoothness specifications to promote construction of pavements that provide road users with the ride quality they expect. A smoothness specification indicates the smoothness level that a contractor must achieve to obtain full payment. In the United States, there is a growing trend of using inertial profilers to collect smoothness data on new portland cement concrete (PCC) pavements and to use the International Roughness Index (IRI) that is computed from the profile data to judge the level of smoothness. Lightweight inertial profilers can collect data on PCC pavement as soon as the PCC has hardened. Repetitive features as well as localized roughness features that are introduced to the pavement profile during paving can be easily detected by analyzing data collected by inertial profilers. This paper illustrates how filtering techniques and power spectral density (PSD) plots can be used to analyze profile data and detect paving problems. The detection of following paving problems from profile data are illustrated in this paper: stringline sag, roughness caused by dowel effects, mechanical oscillating floats, and headers.