Early Detection of Joint Distress in Portland Cement Concrete Pavements

INDOT (as well as several surrounding states) have observed that certain concrete pavements may show a susceptibility to joint deterioration. Unfortunately, by the time that this joint deterioration is observed it is often too late and costly partial depth repairs are needed. The deterioration is generally occurring in the joint behind the backer rod and joint sealant; as such, it is difficult to detect even if one is standing directly above the joint. This project investigated the use of electrical resistivity and ground penetrating radar as two techniques to detect premature joint deterioration. The thought process was that if the joint deterioration is determined at an early stage, low cost corrective actions can be taken to extend the life of the concrete. The electrical response was measured for mortars subjected to a temperature cycle from 23 °C to -35 °C, with varying degrees of saturation, and varying salt concentrations. The resistivity increased as the degree of saturation was reduced due to the reduction in the volume of the conductive medium and increase in tortuosity. Changes in resistivity were detected when cracking occurred in the sample. The magnitude of these changes was similar to that detected using changes in the ultrasonic wave speed. Ground penetrating radar (GPR) was used effectively to detect fluid accumulation in the saw-cut joint behind the joint sealant. The typical GPR waveforms are however difficult and time consuming to interpret. A signal processing approach called, referred to as the CID, was used to obtain a single number that reflects the potential for fluid in the joint. Scalar waveform features and the computed CID can be used to estimate which joints may contain fluid thereby providing insights into which joint sealant sections may need to be repaired or when a sufficient number of joints may contain fluid suggesting a larger joint maintenance effort be performed to seal the joints or the concrete

An Overview of Joint Deterioration in Concrete Pavement: Mechanisms, Solution Properties, and Sealers

Concrete pavements represent a large portion of the transportation infrastructure. While the vast majority of concrete pavements provide excellent long-term performance, a portion of these pavements have recently shown premature joint deterioration. Substantial interest has developed in understanding why premature joint deterioration is being observed in jointed portland cement concrete pavements (PCCP). While some have attributed this damage to insufficient air void systems, poor mixture design, or chemical reaction between the salt and the paste, it is the hypothesis of this work that a component of this damage can be attributed to fluid absorption at the joints. This report begins by discussing the importance of the level of concrete saturation on freeze-thaw damage. Second, this report describes the influence of deicing salt solutions on drying and wetting of concrete. Third, the report describes some observations from field studies. Fourth, the report discusses soy methyl esters polystyrene blends (SME-PS) as a potential method to extend the service life of concrete pavements by limiting the ingress of salt solutions. The report also discusses field application of the SME-PS blends for field investigation. Finally, the report discusses the development of a test to assess chloride solution ingress during temperature cycling. The aim of this work is to provide background on some aspects that can lead to joint deterioration and to provide the pavement community alternatives on how sealers and deicers may be able to be used more efficiently to reduce joint damage

Evaluation of Sealers and Waterproofers for Extending the Life Cycle of Concrete

Concrete pavements represent a large portion of the transportation infrastructure. While the vast majority of concrete pavements provide excellent long-term performance, a portion of these pavements have recently shown premature joint deterioration. Substantial interest has developed in understanding why premature joint deterioration is being observed in jointed portland cement concrete pavements (PCCP). While some have attributed this damage to insufficient air void systems, poor mixture design, or chemical reaction between the salt and the paste, it is the hypothesis of this work that a component of this damage can be attributed to fluid absorption at the joints and chemical reactions between the salt and chemistry of the matrix. This paper discusses the role of soy methyl ester - polystyrene blends (SME-PS) as a potential method to extend the service life of concrete pavements by limiting the ingress of salt solutions. The report discusses field application of the SME-PS blends for field investigation in Lafayette and Fishers. Low temperature-differential scanning calorimetry (LT-DSC) techniques identified noticeable differences between plain mortar samples and mortar treated with SME-PS. The report also discusses the development of a test to assess chloride solution ingress during temperature cycling. The aim of this work is to provide background on some aspects that can lead to joint deterioration and provide early documentation showing that sealers may help to reduce the impact of deicers on joint damage, thereby extending the life of the concrete pavement. It should be noted that these sites as well as others are still ongoing and should be monitored for long term performance. Application procedure for SME-PS should follow manufacturer’s recommendation