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From page 11... ... Standard Definitions for Common Types of Pavement Cracking 4 C H A P T E R 2 Literature Review and Agency Survey Introduction This chapter documents a comprehensive literature review regarding pavement cracking data collection and definitions and survey results from current SHAs' practices. Seven national cracking protocols and 34 state protocols were reviewed and summarized. Read the entire page →
From page 12... ... Standard Definitions for Common Types of Pavement Cracking 5 Automated Survey With the increasing traffic levels on the highways and the need to use network level pavement cracking data, SHAs are moving toward automated surveys to record pavement surface characteristics via digital images. Digital imaging-based automated cracking surveys capture pavement surface images as streams of electronic bits and store them on an electronic medium for pavement cracking condition interpretation (McGhee 2004) Read the entire page →
From page 13... ... Standard Definitions for Common Types of Pavement Cracking 6 including cracking, roughness, rutting, faulting, texture, and geometric characteristics. Automated surveys can greatly reduce errors associated with transferring data from paper forms used in the field to computer systems for analysis. Read the entire page →
From page 14... ... Standard Definitions for Common Types of Pavement Cracking 7 Table 1 Summary of Crack Protocols Protocols Automation Pavement and Cracking Types AASHTO R 85-18 Yes Asphalt: longitudinal, transverse, pattern, and other cracking. AASHTO R 55-10 Yes Asphalt: wheel path and non-wheel path cracking. Read the entire page →
From page 15... ... Standard Definitions for Common Types of Pavement Cracking 8 Table 2 FHWA LTPP Cracking Protocol (continued) Crack Type Severity Levels Low Medium High JPCP Pavement Corner Breaks Spalled crack < 10% crack length; no faulting Spalled crack > 10% crack length; or faulting ≤ 1/2 in. Read the entire page →
From page 16... ... Standard Definitions for Common Types of Pavement Cracking 9 AASHTO R 85-18 Protocol The AASHTO R 85-18 outlines the procedures for quantifying cracking at the network level for asphalt pavement surfaces utilizing automated methods (AASHTO 2018) Read the entire page →
From page 17... ... Standard Definitions for Common Types of Pavement Cracking 10 Table 4 Summary of Crack Protocols by SHAs Agency Automated Pavement and Cracking Types Alabama Yes Project Level  Asphalt: fatigue, block, edge, longitudinal, and transverse cracking.  JPCP & CRCP: corner break, "D", longitudinal, and transverse cracking. Read the entire page →
From page 18... ... Standard Definitions for Common Types of Pavement Cracking 11 Table 4 Summary of Crack Protocols by SHAs (continued) Agency Automated Pavement and Cracking Types Kansas No  Asphalt: fatigue, transverse, and block cracking. Read the entire page →
From page 19... ... Standard Definitions for Common Types of Pavement Cracking 12 Table 4 Summary of Crack Protocols by SHAs (continued) Agency Automated Pavement and Cracking Types Oklahoma No  Asphalt: fatigue, transverse, and miscellaneous cracking. Read the entire page →
From page 20... ... Standard Definitions for Common Types of Pavement Cracking 13 Distress rating protocols from Oregon DOT and Vermont Agency of Transportation (VTrans) are selected as the example protocols to illustrate manual and automated cracking surveys. Read the entire page →
From page 21... ... Standard Definitions for Common Types of Pavement Cracking 14 Table 6 Cracking Protocol for Oregon DOT Crack Type Severity Levels Low Medium High Asphalt Pavements Fatigue Cracking Cracks with little connection are not spalled. Interconnected cracks may be slightly spalled. Read the entire page →
From page 22... ... Standard Definitions for Common Types of Pavement Cracking 15 Based on the comprehensive literature review, the cracking protocols used by SHAs can be highly diversified and, at times, are not comparable from agency to agency in terms of cracking categories, definitions, severity levels, etc. For example, block cracking is included in the LTPP Distress Manual and Oregon DOT surveys, but excluded in AASHTO R 85-18 and VTrans' protocol. Read the entire page →
From page 23... ... Standard Definitions for Common Types of Pavement Cracking 16 Figure 3 Map of survey respondents with states in red as responding states. Part I: Cracking Data Collection, Processing, and Common Issues As shown in Figure 4a, 13, 10, 9, and 30 of the 39 responses, respectively, use manual surveys (including windshield surveys) Read the entire page →
From page 24... ... Standard Definitions for Common Types of Pavement Cracking 17 (a) Data collection and processing methods. Read the entire page →
From page 25... ... Standard Definitions for Common Types of Pavement Cracking 18 Transverse Cracking All responding SHAs collect transverse cracking data, 33 measure transverse cracking over the full width of a travel lane, and 33 use crack width to classify the severity levels. As shown in Figure 5a, 8, 3, and 6 SHAs apply 45 ̊ to 90 ̊, 80 ̊ to 100 ̊, and 90 ̊ of angle orientation to classify and distinguish transverse cracking from other cracking types, respectively. Read the entire page →
From page 26... ... Standard Definitions for Common Types of Pavement Cracking 19 and 6, respectively, to define longitudinal cracking. Respondents report linear length, the number of slabs affected (JPCP only) Read the entire page →
From page 27... ... Standard Definitions for Common Types of Pavement Cracking 20 SHAs (24) still would like to maintain the interconnectivity of cracking as the criteria to rate the severity levels for alligator/fatigue cracking (Figure 7d) Read the entire page →
From page 28... ... Standard Definitions for Common Types of Pavement Cracking 21 (a) Block cracking collection. Read the entire page →
From page 29... ... Standard Definitions for Common Types of Pavement Cracking 22 (a) Extent evaluation factors. Read the entire page →
From page 30... ... Standard Definitions for Common Types of Pavement Cracking 23 (a) Sealed cracking collection. Read the entire page →
From page 31... ... Standard Definitions for Common Types of Pavement Cracking 24 Part IV: AASHTO R 85-18 Applications As reported in AASHTO R 85-18, the total cracking length and average cracking width of each cracking type are reported for each of the five zones (Figure 2) Read the entire page →
From page 32... ... Standard Definitions for Common Types of Pavement Cracking 25  2D and 3D image-based automated data collection is the dominant approach to cracking data collection and processing among the SHA respondents.  Agency-specific (30%) Read the entire page →

From page 11...

... Standard Definitions for Common Types of Pavement Cracking 4 C H A P T E R 2 Literature Review and Agency Survey Introduction This chapter documents a comprehensive literature review regarding pavement cracking data collection and definitions and survey results from current SHAs' practices. Seven national cracking protocols and 34 state protocols were reviewed and summarized.