1、Standard Practice for Evaluating Faulting of Concrete Pavements AASHTO Designation: R 36-171 Technical Section: 5a, Pavement Measurement Release: Group 1 (April 2017) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS
2、-5a R 36-1 AASHTO Standard Practice for Evaluating Faulting of Concrete Pavements AASHTO Designation: R 36-171Technical Section: 5a, Pavement Measurement Release: Group 1 (April 2017) 1. SCOPE 1.1. This standard describes a test method for evaluating faulting in jointed concrete pavement surfaces ba
3、sed on manual methods and automated methods. 1.2. Faulting is defined as the difference in elevation across a transverse joint or crack as illustrated in Figure 1. Figure 1Faulting of Transverse Joints or Cracks (See Section 10.1) 1.3. Detailed specifications are not included for equipment or instru
4、ments used to make the measurements. Any equipment that can measure faulting with the accuracy stipulated herein and that can be adequately calibrated is considered acceptable. 1.4. This standard practice may involve hazardous materials, operation, and equipment. The procedure does not purport to ad
5、dress all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this protocol to establish appropriate safety and health practices and determine the applicability of regulatory limitations related to and prior to its use. AABBTrafficFault (positive) Fault (
6、negative)TrafficJointEdgeJointJointShoulderCL 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-2 AASHTO 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 328, Inertial Profiler R 56, Certificati
7、on of Inertial Profiling Systems R 57, Operating Inertial Profiling Systems 3. TERMINOLOGY 3.1. Definitions: 3.1.1. filteringfiltering technique that excludes the wavelength contents other than those within the selected wave band. 3.1.2. longitudinal profilethe set of perpendicular deviations of the
8、 pavement surface from an established horizontal reference plane to the lane direction. 3.1.3. outside wheelpatha longitudinal strip of pavement 0.75 m (30 in.) wide and centered 0.875 m (35 in.) from centerline of the lane toward the shoulder. 3.1.4. spallingbreakdown or disintegration of slab edge
9、s at joints or cracks usually resulting in the loss of sound concrete. 3.2. Definitions of Terms Specific to this Standard: 3.2.1. automated faulting measurement (AFM)a module in the Federal Highway Administration (FHWA) Profile Viewing and Analysis (ProVAL) software, used to automatically process l
10、ongitudinal profiles for faulting computation and reporting based on Method A (see Section 6) of this standard. 3.2.2. automated faulting program (AFP)an Excel-based application developed by Florida Department of Transportation under the AASHTO Technology Implementation Group (TIG) program used to a
11、utomatically process longitudinal profiles for faulting computation and joint detection reporting based on Method B (see Section 7) of this standard. 3.2.3. faultmetersa type of device for manual fault measurement based on contact-type methodology. 3.2.4. high-speed inertial profiler (HSIP)a vehicle
12、 equipped with laser height sensors and accelerometers to measure longitudinal profiles based on non-contact-type technology. 4. MANUAL FAULT MEASUREMENT 4.1. It is each agencys responsibility to designate the lane(s) and direction(s) of travel to be surveyed on the basis of sound engineering princi
13、ples and pavement management needs within the agency. 4.2. Include the sampling rate level of at least 10 percent of all transverse joints or transverse cracks. The 10 percent sampling rate should be uniformly spaced (preferably every tenth joint or crack or more frequently) throughout the project t
14、o assess the condition. The location should be documented along with the measurement. 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-3 AASHTO 4.3. Record all faulting measured. It is recommen
15、ded that a precision for faulting be established such that it is calculated to the nearest 1mm (0.04 in.). Note 1Care must be taken to not measure spalling and classify it as faulting. 4.4. Use a faultmeter to measure faulting across transverse joints and cracks in the outside wheelpath of the surve
16、y lane at a sampling rate designated by the agency. The faultmeter should be a straightedge type of device as illustrated in Figure 2. An example of faultmeters and their operations are described in Appendix X2. Figure 2Manual Faulting Measurement with a Generic Faultmeter 4.5. Calculate faulting (F
17、) using the following formula: FMH= (1) where: F = faulting, mm (in.); M = height for measurement Leg 3, mm (in.); H = height for Leg 1 and Leg 2, mm (in.); A = distance between Leg 1 and Leg 2, mm (in.); B = C + D; B is recommended to be 300 mm (11.8 in.); C = distance between Leg 2 and the joint l
18、ocation with a value between 76 mm and 226 mm (3 in. and 8.9 in.); and D = distance between the joint location and Leg 3 with a value between 76 mm and 226 mm (3 in. and 8.9 in.). 4.6. See Appendix X2 for determining faulting at the joint using the concept of a faultmeter with an inclinometer. 5. AU
19、TOMATED FAULT MEASUREMENT 5.1. It is each agencys responsibility to designate the lane(s) and direction(s) of travel to be surveyed on the basis of sound engineering principles and pavement management needs within the agency. 5.2. The measurements should comply with the following best practices: 5.2
20、.1. The HSIP equipment should comply with M 328. 5.2.2. The operation of HSIP equipment should comply with R 57. JointFaultmeterAHBLeg 1Leg 2Leg 3CDMApproach SlabDeparture Slab 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violat
21、ion of applicable law.TS-5a R 36-4 AASHTO 5.2.3. The repeatability and accuracy scores based on cross correlation under R 56 are recommended to be greater than or equal to 92 percent and 90 percent, respectively. 5.2.4. For project-level survey, the sampling interval needs to be 19 mm (0.75 in.) or
22、less. No digital filtering during postprocessing of data shall be allowed. Automated triggering is recommended to locate the start and end of survey sections with high precision. 5.2.5. For network-level surveys, the sampling interval needs to be 38 mm (1.5 in.) or less. No digital filtering during
23、postprocessing of data shall be allowed. 5.2.6. Profile data should be collected for both left and right wheelpaths. 5.2.7. Observation should be recorded for profiler sensor footprint, aggressive surface textures, tining, slope/grade, spalling, curl/warp, skewed joints, and sealant-filled joints. 5
24、.3. Users can elect either Method A (see Section 6) or Method B (see Section 7) to process the HSIP data to compute faulting. 6. METHOD APROCESS OF AUTOMATED MEASUREMENTS 6.1. The data processing and reporting should comply with the following best practices for identifying locations of joints/cracks
25、 and computing faults. Method A consists of a two-step process. Firstly, joint/crack locations are identified, then an algorithm is used to compute faulting for each joint/crack location. Note 2The AFM module in the FHWA ProVAL software (www.RoadP) is recommended for data processing and reporting, t
26、o ensure consistent results based on Method A (see Section 10.2). 6.2. Identify joint/crack locations using an automated method: downward spike detection, step detection, and curled edge detection (see Figure 3). Figure 3Identification of Joint and Crack Locations 6.2.1. Use the downward spike detec
27、tion method when profiles consist of downward spikes at joint and crack locations. (See Section 10.3.) 6.2.1.1. Perform anti-smoothing filtering using a moving average filter at a cutoff of 250 mm (9.84 in.). -60 -55 -50 -45 -40 -0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170- - - - -
28、- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Elevation (cm)Distance (m)Joint Locations Cracks 01_US49_int18_Left Elevation 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-5 AASHT
29、O 6.2.1.2. Normalize the filtered profile with its root mean squares (RMS) and produce the spike profile, i.e., making the spike profile unitless. 6.2.1.3. Detect the locations where the spike profile values exceed a threshold value (the starting threshold is 4.0), but avoid multiple hits within a c
30、learance width, 0.5 m (1.64 ft). 6.2.1.4. Screen the above locations to differentiate joints from cracks. 6.2.2. Use the step detection method when faulting is noticeable on profiles. (See Section 10.4.) 6.2.2.1. Deduct profile elevations between consecutive data points resulting in elevation differ
31、ences. 6.2.2.2. Detect the locations where the absolute values of the elevation differences exceed a threshold value (the starting threshold value is 2.032 mm or 0.08 in.) but avoid multiple hits within a clearance width of 0.91 m (3 ft). 6.2.2.3. Screen the above locations to differentiate joints f
32、rom cracks. 6.2.3. Use the curled-edge detection method if slab curls are noticeable. (See Section 10.2.) 6.2.3.1. Perform bandpass filtering using a moving average filter with short cutoff at 250 mm (9.84 in.) and long cutoff wavelength at 50 m (150 ft). 6.2.3.2. Simulate a rolling straightedge res
33、ponse with base length of 3 m (9.8 ft). 6.2.3.3. Detect the locations where the simulated rolling straightedge responses exceed a threshold value (the starting threshold is 3 mm or 0.12 in.) but avoid multiple hits within a clearance width of 0.5 m (1.64 ft). 6.2.3.4. Screen the above locations to d
34、ifferentiate joints from cracks. 6.3. Compute faulting following the best practices: 6.3.1. Crop a profile segment that centers a joint with a length of 2.438 m (8 ft). 6.3.2. Separate the profile slices for the approach slab and departure slab (i.e., 1219 mm or 48 in. for each slice). 6.3.3. For th
35、e profile slice from the approach slab, mask the area close to the joint based on the joint window input and perform least squares fitting. The fitting would extend to the departure side of the joint for an offset between 76 mm and 226 mm (3 in. and 8.9 in.). Obtain the elevations at the downstream
36、end of the fitted line for later fault computation as P1icorresponding to all data points within this offset. 6.3.4. For the profile slice from the departure slab, mask the area close to the joint based on the joint window input and perform least squares fitting. The fitting would be performed from
37、the downstream end of the slice toward the joint location. Obtain the elevations at all data points with an offset between 76 mm and 226 mm (3 in. and 8.9 in.) from the joint location toward the downstream end of the fitted line (i.e., matching the exact horizontal locations of the elevation readout
38、 value from the above step) as P2icorresponding to all data points within this offset. 6.3.5. Take the differences in the elevations from the above two steps as individual elevation differences (fi), then compute the faulting using the following formula: 2017 by the American Association of State Hig
39、hway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-6 AASHTO ( )1211n iiniiiPPfFnn= =(2) where: F = calculated faulting, mm (in.); fi= elevation differences between 1iP and 2iP at locations of data points within the offset range, mm (in.); n
40、 = number of data points within the offset range. 1iP = elevation at the fitted line for the profile slice on the approach slab at locations of data points within the offset range, mm (in.); and 2iP = elevation at the fitted line for the profile slice on the departure slab at locations of data point
41、s within the offset range, mm (in.). Figure 4Curve-Fitting of Cropped Profile Slices and Computation of Faulting 7. METHOD BPROCESS OF AUTOMATED MEASUREMENTS 7.1. The data processing and reporting should comply with the following best practices for identifying locations of joints/cracks and computin
42、g faults. Method B combines the joint/crack locations identification and fault computation in one process. Note 3The Automated Fault Program (AFP), an Excel-based application developed by Florida Department of Transportation under the AASHTO Technology Implementation Group (TIG) program, is recommen
43、ded for the data processing and reporting to ensure consistent results based on Method B (see Sections 10.5, 10.6, and 10.7). 7.2. Follow these best practices to identify joint/crack locations and estimate faulting by setting the parameters in such a way that the AFP performs the following tasks: 7.
44、2.1. Automatically sets a seed value for the sensitivity factor (SF) as: 0.01SF SA= (3) 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-7 AASHTO where: SF = the slope between two consecutive p
45、rofile points, unitless; and SA = profile sampling interval, mm (in.); 7.2.2. Calculates the vertical grade between consecutive profile elevation points, mm/mm (in./in.); 7.2.3. Identifies a joint or crack location where the calculated grade is greater than the SF; 7.2.4. Calculates relative elevati
46、on change between sets of profile points P1and P2separated by a distance of 300 mm (11.8 in.); 7.2.5. Calculates faulting, F, as the average of all individual elevation changes (fi) calculated in the previous step: ( )1211nnii iPPfFnn= =(4) where: F = calculated faulting, mm (in.); fi= individual el
47、evation change, mm (in.); and n = number of data sets, P1and P2, within the 76.2-mm (3.0-in.) to 223.5-mm (8.8-in.) range from the center of a joint or crack; Figure 5Profile Elevation Points P1and P2Are Used to Estimate Faulting 7.2.6. Calculates the theoretical joint count, JCTcalculated as: TTLJC
48、SL=(5) where: JCT= theoretical joint count for the pavement section tested; TL = total length of the tested pavement section, m (ft); and SL = user input slab length, m (ft); 223.5 mmPPfd9 = 300 mmd3 = 300 mmd2 = 300 mmd1 = 300 mmfJoint76 mm211976 mm 223.5 mm 2017 by the American Association of Stat
49、e Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-5a R 36-8 AASHTO 7.2.7. Performs up to nine additional iterations optimizing SF until the number of detected joints matches or is closest to JCT; 7.2.8. Recalculates joint locations and faulting magnitudes; 7.2.9. Saves joint location and faulting magnitude for the optimum SF. 8. REPORT 8.1. At a minimum, report the following items for each test section: 8.1.1. Section Identification; 8.1.2. Date and time of data collec
