Chapter 12: Premature Distress InvestigationsAnchor: #i999637
Section 1: OverviewAnchor: #i999643
Premature pavement failures typically occur within the first half of a rigid pavement’s design life and within 5 years after completion of the project for flexible pavements. Premature pavement failures can be attributed to any number of factors or combination of those factors, including inadequate structural design or incorrectly addressing existing structural deficiencies, inadequate consideration of design compatibility with the abutting pavement, poor quality or non-uniform materials, inadequate surface preparation, or poor construction. Despite advancements in pavement technology in past decades, premature failures and chronic pavement distresses continue to occur. Experience has shown that the majority of premature pavement failures in Texas are related to material and construction deficiencies. Material deficiencies can be related to inadequate assessment of existing materials and what measures are needed to enhance their attributes for better performance. Although improvements have been made to construction specifications, equipment, and construction processes, poor quality construction or use of substandard materials can occur due to a number of complex and sometimes competing variables, such as:
- Anchor: #RURCKVJM
- reduced inspection staffing, Anchor: #MSUEKRPG
- employee turnover, Anchor: #SILQVMRF
- fluctuations in levels of experienced inspectors, project managers and engineers, Anchor: #AMCEUVWK
- incompatibilities between new admixtures and construction materials, Anchor: #TDOOPNCB
- implementation of new technologies, construction methods, and best practices, Anchor: #JIGUUJNQ
- environmental constraints and recycled materials, Anchor: #CPCBLGQV
- issues unforeseen during design and construction phases.
To prevent or reduce the probability of premature pavement distress and poor long term pavement performance, the root causes of these problems have to be identified. It is a challenging task to determine the causes of pavement distress. A pavement distress investigation involves a thorough review and analysis of existing construction quality control records and tests, and nondestructive testing such as ground penetrating radar (GPR), falling weight deflectometer (FWD), and dynamic cone penetration testing (DCP). These are essential to identify problematic areas and probable causes. Additional field testing, such as portable FWD, dirt seismic pavement analyzer (DSPA), coring, trenching, and laboratory testing, may be conducted to confirm the initial hypothesis. The outcomes from investigations can be used to validate or modify the existing design plan and to resolve the disputes involving construction claims or change orders.Anchor: #i1000734
1.2 Technical Assistance
For technical assistance requests, contact the Materials and Pavements Section of the Construction Division (CST-M&P). Requests for technical assistance are best made as early as possible after becoming aware of the distress to allow opportunity to correct problems if the project is still under construction, prevent further pavement distress, obtain samples of materials actually used on the project for lab testing, and to allow time for appropriate remediation.