Click for next page ( 49


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 48
48 Table 5-1. Summary of PSD texture parameters for new test sections. Peak Spectrum Sect Wavelength, No. Texture Description L4 L63 L4/L63 A1 A2 A1/A2 mm 1a Long Heavy Turf Drag 51 51 1 411 621 0.66 25 1b Long Heavy Turf Drag (mod) 44 50 0.88 357 667 0.54 30 2 Long Tine (0.75-in. spacing, 0.125-in. depth), no pretexture 35 47 0.74 286 659 0.43 70 3 Long DG (no jacks), 0.235-in. spacing (0.11-in. spacers) 53 50 1.06 428 776 0.55 25 5a Long Tine (0.75-in. spacing, 0.125-in. depth), turf drag 32 44 0.73 258 608 0.43 50 5b Long Tine (0.75-in. spacing, 0.125-in. depth), heavy turf drag 23 39 0.59 193 486 0.40 50 6 Long Tine (0.75-in. spacing, 0.075-in. depth), turf drag 34 47 0.72 277 640 0.43 65 7 Long Groove (0.75-in. spacing, 0.25-in. depth), burlap drag 28 21 1.33 225 322 0.70 15 8 Long Groove (0.75-in. spacing, 0.25-in. depth), turf drag 35 32 1.09 289 464 0.62 15 9 Tran Tine (0.5-in. spacing, 0.125-in. depth), burlap drag 51 60 0.85 385 796 0.48 40 (GA design) 10 Tran Tine (variable spacing, 0.125-in. depth), burlap drag 40 52 0.77 308 699 0.44 45 11 Tran Tine (1.0-in. spacing, 0.125-in. depth), burlap drag 39 52 0.75 305 682 0.45 40 (old ISTHA std) 12 Tran Skew Tine (variable spacing, 0.125-in. depth), turf 38 47 0.81 310 636 0.49 40 drag (new ISTHA std) of wavelength) were determined. Table 5-1 summarizes the spectral characteristics. In addition to a relatively small data PSD values obtained for the various textures. The resulting set, the two-dimensional profile used to represent a three- texture spectra showed peaks occurring at considerably lower dimensional profile from which the actual noise was measured wavelengths for the heavy turf drag textures and the diamond- also limited the relationship. ground and groove textures, which were among the quietest textures. Comparative/Qualitative Analyses Figures 5-14 through 5-16 are plots of near-field SI as functions of L4 /L63, A1 /A2, and peak spectrum, respectively. This analysis considers data obtained from the measure- These data show a somewhat linear relationship between SI ments on the existing and newly constructed test sections to and L4/L63 and between SI and A1/A2. These relationships develop a basic understanding of each texture's performance hold to the principles of reducing higher wavelength tex- characteristics in terms of micro- and macro-texture, friction, ture and increasing lower wavelength texture in order to and noise. The analysis included the following: reduce noise. The three relationships were expected to be limited because Comparison of textures by site/location. noise depends on other factors (e.g., texture depth, direction, Texture durability analysis. and orientation; and pavement porosity and stiffness) besides Comparison of textures by noise. 106 Near-Field SI, dB(A) 105 104 y = -3.8833x + 106.01 103 2 R = 0.5136 102 101 100 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 L4/L63 Figure 5-14. Near-field SI noise versus L4 /L63 profile level ratio.

OCR for page 48
49 106 105 Near-Field SI, dB(A) 104 y= -7.1436x+ 106.262 103 R = 0.4467 102 101 100 0.00 0. 0.20 0.40 0.60 0.80 1.00 A1/A 2 Figure 5-15. Near-field SI noise versus A1 /A2 ratio. Relationship of near-field noise with interior and pass- cumulative traffic were presented for tests in the wheelpath by noise. and at the lane center. In these cases, traffic data (yearly ADT Texture variability analysis. values and truck percentages, estimated directional and lane distribution factors) provided by the respective state DOTs were used to estimate cumulative combined traffic (cars and Comparison of Textures by Site/Location trucks) and truck traffic applications at time of testing, using In this analysis, the textures at the different test sites/locations the following assumptions: were compared and ranked in terms of their relative perfor- mance as defined by qualitative friction and noise levels. The right wheelpath (defined by an 18-in. [460-mm] wide Summary tables were prepared that present the texture, fric- swath) experiences 90 to 95 percent of the combined lane tion, noise, and smoothness results (mean values) for each traffic. texture, and the corresponding rankings (1=best, 2=next The lane center (defined by an 18-in. [460-mm] wide best, etc.) for friction, noise, and smoothness. Key observations swath), equally spaced between wheelpaths experiences are then made concerning the rankings and overall qualitative 1 percent of the combined traffic and 0.5 percent of the performance. truck traffic. The relative rankings of each set of test results are provided in parentheses in the summary tables. In some cases (e.g., Illi- For evaluating the effect of traffic on the performance of nois Tollway, Colorado US 287), the test results were obtained textures, traffic levels were categorized as low traffic (less than before opening the road to traffic, thus reflecting an untraf- 5,000,000 cumulative vehicles and/or less than 500,000 cumu- ficked pavement. In other cases (e.g., Arizona SR 202, Califor- lative trucks) and high traffic (more than 5,000,000 cumulative nia SR58), two sets of test results reflecting different levels of vehicles and/or more than 500,000 cumulative trucks). 106 y = 0.0385x + 101.04 105 Near-Field SI, dB(A) 2 R = 0.2913 104 103 102 101 100 0 10 20 30 40 50 60 70 80 Peak Texture Wavelength, mm Figure 5-16. Near-field SI noise peak texture wavelength.

OCR for page 48
50 Because there are no established criteria for defining what Sections 1003 and 1004 that exhibited the greatest tex- is good, fair, and poor with respect to friction and noise, it ture deterioration rates (MTD reduction of 0.02 to 0.03 mm was necessary to establish and apply some form of criteria to per million vehicles [0.1 to 0.58 mm per million trucks]) the test results to aid in the development of a texture selec- showed mixed effects on friction and noise (Section 1003 tion process. Using information from the literature (e.g., showed no or only slight change in friction and noise, and Pottinger and Yager, 1986; Wambold, Henry, and Hegmon, Section 1004 showed large reduction in friction and only 1986; Rasmussen et al., 2007b), the ranges of friction and noise slight change in noise). shown in Table 5-2 were identified and used as qualitative Texture, friction, and noise were not noticeably affected by indicators. use of jacks. Noise spectra did not identify tonal issues for any of the textures. Arizona Sections The four diamond-ground sections at this site, located on California Sections SR 202L in Phoenix, were constructed in summer 2003 and opened to traffic in fall 2003. Texture, friction, and noise The surface textures on these sections were constructed testing was performed approximately 2 years later. The four between fall 2002 and summer 2003. The facility was opened textures are as follows: to traffic in fall 2003, and texture, friction, and noise mea- surements were made about 2 years later. These sections are 1001--Long DG (no jacks), 0.235-in. (6.0-mm) spacing described as follows: (i.e., 0.11-in. [2.8-mm] spacers). 1002--Long DG (jacks), 0.235-in. (6.0-mm) spacing (i.e., 1002--Long DG (no jacks), 0.245-in. (6.2-mm) spacing 0.11-in. [2.8-mm] spacers). (i.e., 0.12-in. [3.0-mm] spacers). 1003--Long DG (no jacks), 0.245-in. (6.2-mm) spacing 1003--Long groove, 0.75-in. (19-mm) spacing, 0.125-in. (i.e., 0.12-in. [3.0-mm] spacers), fins scraped with motor (3.2-mm) depth, burlap drag. grader at time of construction. 1004--Long groove, 0.75-in. (19-mm) spacing, 0.25-in. 1004--Long DG (jacks), 0.245-in. (6.2-mm) spacing (i.e., (6.4-mm) depth, burlap drag. 0.12-in. [3.0-mm] spacers). 1045--Long burlap drag 1005--Long DG (no jacks), 0.23-in. (5.8-mm) spacing (i.e., Table 5-3 summarizes the texture, friction, and noise data 0.105-in. [2.7-mm] spacers). collected on these sections, including test measurements made 1007--Long groove, 0.375-in. (9.5-mm) spacing, 0.25-in. by the state DOT (Scofield, 2003) at the time of construction. (6.4-mm) depth, broom drag. The following are key observations concerning the perfor- 1075--Long broom drag. mance of these sections (the noise comparisons discussed below are based only on relative rankings associated with each Table 5-4 summarizes the texture, friction, and noise infor- noise parameter [i.e., CPX during construction, SI for low mation collected on the sections, including test measurements traffic and high traffic]): made at the time of construction by Caltrans (Donavan, 2003). Key observations concerning the performance of these sec- In comparison to Section 1002, Section 1004 with wider tions are as follows: groove spacing and lower texture depth and TR exhibited lower noise and lower friction. Drag-textured sections (1045 and 1075) had the lowest Section 1003 with the highest texture depth and TR has pro- texture depths and generally showed lowest levels of duced the highest near-field and interior noise and highest friction. However, the effect of texture depth on noise was level of friction, and indicated that smoothness may have inconsistent. Section 1045 with burlap drag texture showed some direct effect on noise. moderate near-field and interior noise, and the sections Table 5-2. Qualitative designations for friction and noise parameters. Friction Parameters Noise Parameters Qualitative Near-Field SI, Interior Noise Designation FN40R FN40S IFI F(60) dB(A) Leq, dB(A) Low <35 <28 <28 <102 <69 Moderate 35 to 45 28 to 40 28 to 40 102 to 106 69 to 72.5 High >45 >40 >40 >106 >72.5

OCR for page 48
Table 5-3. Summary of test results for Arizona SR 202L texture sections. 1 2 3 Construction Low Traffic (LC) High Traffic (WP) Texture Smooth Friction Noise Texture Smooth Friction Noise Texture Smooth Friction Noise Sect Design Actual Near Near Near Groove Groove Field HS CTM Field Int HS CTM Field Int Depth, Depth, IRI, CPX, EMTD, MTD, CTM IRI, DFT SI, Leq, EMTD, MTD, CTM IRI, DFT SI, Leq, mm mm in./mi RFT dB(A) mm mm TR in./mi F(60) dB(A) dB(A) mm mm TR in./mi F(60) dB(A) dB(A) 1001 3.2-6.4 32.7 (2) 65 (4) 97.5 (3) 0.71 1.07 2.37 (2) 73.2 (2) 41.9 (2) 104.6 (1) 70.3 (1) 0.71 1.04 2.24 (2) 69.4 (1) 41.5 (2) 104.4 (1) 70.4 (2) 1002 3.2-6.4 34.2 (3) 66 (3) 98.0 (4) 0.72 1.12 2.41 (3) 80.7 (3) 40.8 (3) 105.6 (3) 71.4 (3) 0.70 1.07 2.27 (3) 80.9 (3) 39.2 (3) 105.8 (3) 72.2 (3) 1003 3.2-6.4 28.9 (1) 69 (1) 97.0 (2) 0.92 1.75 2.49 (4) 98.1 (4) 46.4 (1) 106.4 (4) 73.5 (4) 0.92 1.56 2.42 (4) 94.0 (4) 47.4 (1) 106.3 (4) 73.5 (4) 1004 3.2-6.4 38.5 (4) 67 (2) 95.5 (1) 0.73 0.87 1.89 (1) 70.8 (1) 36.5 (4) 104.7 (2) 70.3 (1) 0.64 0.70 1.58 (1) 74.2 (2) 32.2 (4) 104.9 (2) 69.9 (1) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Measurements by Arizona DOT. 2 Estimated 58,000 to 93,000 cumulative vehicles (1,600 to 11,000 cumulative trucks). 3 Estimated 5,800,000 to 9,300,000 cumulative vehicles (319,000 to 2,100,000 cumulative trucks). RFT=Runway Friction Tester Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
Table 5-4. Summary of test results for California SR 58 texture sections. 1 2 3 Construction Low Traffic (LC) High Traffic (WP) Texture Smooth Friction Noise Texture Smooth Friction Noise Texture Smooth Friction Noise Design Actual Near Near Groove Groove HS CTM Field Int HS CTM Field Int Sect Depth, Depth, IRI, SI, EMTD, MTD, CTM IRI, DFT SI, L eq , EMTD, MTD, CTM IRI, DFT SI, L eq , mm mm in./mi CFT dB(A) mm mm TR in./mi F(60) dB(A) dB(A) mm mm TR in./mi F(60) dB(A) dB(A) 1002 1.6-3.2 46.5 (1) 102.3 (6) 0.71 0.96 1.97 (6) 60.5 (2) 40.1 (3) 105.1 (7) 68.8 (2) 0.67 0.67 1.77 (7) 55.1 (1) 33.7 (3 ) 106.2 (5) 68.9 (2) 1003 3.2 42.0 (4) 101.6 (3) 0.80 1.12 0.69 (2) 159.2 (6) 41.4 (2) 104.5 (4) 69.2 (4) 0.76 1.08 0.75 (2) 145.6 (5) 36.7 (2) 105.1 (3) 69.7 (3) 1004 6.4 41.0 (5) 102.0 (4) 1.00 1.31 0.57 (1) 156.7 (5) 44.7 (1) 104.9 (6) 69.5 (5) 0.89 1.29 0.52 (1) 172.7 (6) 38.3 (1) 105.6 (4) 70.3 (5) 1045 101.4 (2) 0.63 0.35 1.84 (4) 78.5 (4) 38.2 (5) 104.0 (1) 68.9 (3) 0.63 0.36 1.55 (4) 90.0 (4) 33.1 (4) 104.9 (2) 69.7 (3) 1005 1.6-3.2 45.5 (2) 100.9 (1) 0.67 0.90 2.00 (7) 58.4 (1) 37.7 (6) 104.4 (3) 67.8 (1) 0.64 0.73 1.65 (5) 56.6 (3) 31.9 (6 ) 104.5 (1) 67.9 (1) 1007 6.4 44.0 (3) 102.8 (7) 0.73 1.54 0.86 (3) 64.6 (3) 39.1 (4) 104.7 (5) 70.6 (7) 0.70 1.62 0.88 (3) 56.1 (2) 32.9 (5) 106.5 (7) 71.2 (6) 1075 102.2 (5) 0.33 1.89 (5) 26.0 (7) 104.3 (2) 70.5 (6) 0.35 1.65 (5) 22.4 (7) 106.2 (5) 71.5 (7) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Measurements by Caltrans. 2 Estimated 36,000 to 54,000 cumulative vehicles (7,000 to 11,000 cumulative trucks). 3 Estimated 3,600,000 to 5,400,000 cumulative vehicles (1,400,000 to 2,100,000 cumulative trucks). CFT=California Friction Tester Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
53 with broom drag texture showed a high level of near-field (Ardani and Outcalt, 2005). Key observations concerning the noise. performance of these sections are as follows: Diamond-ground sections (1002 and 1005) that had the second lowest texture depths showed differing friction Longitudinal Drag Section 1008 with the lowest texture and noise results. The narrower spacing of Section 1005 depth consistently showed the lowest levels of friction and resulted in the lowest overall near-field and interior noise noise with time/traffic. Although F(60) values derived from and one of the lowest levels of friction. The wider spacing the DF Tester measurements showed moderate levels of of Section 1002 resulted in higher friction and relatively friction in 2005, earlier locked-wheel friction tests by low interior noise, but the highest near-field noise of all CDOT showed low friction FN40S values for this section. sections. Longitudinal groove and longitudinal-tine sections (1007 Longitudinal grooved sections (1003, 1004, and 1007) had and 1009) had similar texture depths initially, but the section the highest texture depths and lowest TR values. Friction with tine texture exhibited greater reduction in depth with was highest for the sections with wider spacing textures time/traffic. Friction levels over time/traffic for these two tex- (1003 and 1004) and lower for the sections with narrower tures have been similar. Near-field and interior noise has texture spacing (1007). Narrower texture spacing has shown been consistently highest for the longitudinal-tine section. the highest (or nearly highest) near-field and interior noise. No effect of smoothness on noise was evident. The smoothest Although differences were small, the shallower groove depth section (1008) exhibited the lowest noise, but the roughest (0.125 in. [3.2 mm]) and correspondingly lower texture section(1007)exhibited lower noise than the second smooth- depth of Section 1003 resulted in slightly lower friction and est section (1009). Texture deterioration has been highest for the longitudinal- slightly lower noise than that of Section 1004 with the deeper groove depth (0.25 in. [6.4 mm]). tine section (1009) with MTD reduction of 0.005 mm per Effect of smoothness on noise was not consistent. The million vehicles (0.01 mm per million trucks) and lowest smoothest sections (1002, 1005, and 1007) exhibited the for the longitudinal groove section (1007). Effects of texture deterioration on friction and noise were not clear. All sec- highest and lowest noise levels, and the roughest sections tions experienced similar friction deterioration rates, and (1003 and 1004) exhibited moderate noise levels. the longitudinal-tine section (1009) experienced the lowest Diamond-ground Sections 1002 and 1005 showed the great- rate of increase in noise. est texture deterioration rates (MTD of 0.03 to 0.05 mm per Noise spectra identified no tonal issues for any of the million vehicles [0.08 to 0.14 mm per million trucks]); how- textures. ever, friction and noise deterioration rates were generally similar to those of other texture sections. Sections on US 287. These test sections, located on US 287 Noise spectra did not identify tonal issues for any of the near Berthoud, were constructed between fall 2004 and sum- textures. mer 2005. Texture, friction, and noise measurements were made in fall 2005 (long before opening to traffic in June 2006). Colorado Sections Descriptions of these test sections are as follows: Sections on I-70. These test sections, located near Agate/Deer 3001--Long heavy turf drag. Trail, were constructed between July and September 1994, and 3002--Long tine, 0.75-in. (19-mm) spacing, 0.1875-in. opened to traffic in the OctoberNovember 1994 timeframe. (4.9-mm) depth, no pretexture. Texture, friction, and noise measurements were made approx- 3003--Long meander tine, 0.75-in. (19-mm) spacing, imately 11 years later, in October 2005. These test sections are 0.125-in. (3.2-mm) depth, no pretexture. described as follows: 3004--Long groove, 0.75-in. spacing (19-mm), 0.125-in. (3.2-mm) depth, turf drag. 1007--Long groove, 0.75-in. (19-mm) spacing, 0.125-in. 3005--Long DG (no jacks), 0.22-in. (5.6-mm) spacing (3.2-mm) depth, turf drag. (i.e., 0.095-in. [2.4-mm] spacers). 1008--Long turf drag. 3006--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. 1009--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. (3.2-mm) depth, turf drag. (3.2-mm) depth, turf drag. Table 5-6 summarizes the texture, friction, and noise infor- Table 5-5 summarizes the texture, friction, and noise infor- mation collected on the test sections. Because measurements mation collected on these sections, including test measure- were made prior to opening of the facility to traffic, an assess- ments made by Colorado DOT at the time of construction ment of the effects of traffic could not be made. The following

OCR for page 48
Table 5-5. Summary of test results for Colorado I-70 sections. 1 2 3 Construction Low Traffic (LC) High Traffic (WP) Texture Smooth Friction Noise Texture Friction Texture Smooth Friction Noise Sect No . Design Actual Sand Near Near Groove Groove Patch Field Int CTM HS CTM Field Depth, Depth, MTD, PI0.2, SPL, SPL, MTD, CTM DFT EMTD, MTD, CTM IRI, DFT SI, Int Leq, mm mm mm in./mi FN40R FN40S dB(A) dB(A) mm TR F(60) mm mm TR in./mi F(60) dB(A) dB(A) 1007 3.2 5.81 1.24 1.7 (1) 53.1 (2) 55.2 (2) 99 (1) 66 (1) 1.30 0.92 (2) 48.4 (1) 1.08 1.41 0.97 (1) 199 (3) 42.8 (2) 105.9 (2) 69.4 (2) 1008 0.79 0.51 1.7 (1) 52.0 (3) 30.4 (3) 99 (1) 66 (1) 0.37 1.78 (3) 39.8 (3) 0.67 0.34 1.62 (3) 107 (1) 36.6 (3) 104.4 (1) 68.6 (1) 1009 3.2 3.96 1.19 1.8 (3) 64.4 (1) 56.4 (1) 101 (3) 68 (3) 0.93 1.08 (1) 47.5 (2) 0.98 0.86 1.05 (2) 131 (2) 44.1 (1) 106.1 (3) 69.8 (3) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Measurements by Colorado DOT. 2 Estimated 145,000 cumulative vehicles (30,000 cumulative trucks). 3 Estimated 14,500,000 cumulative vehicles (5,900,000 cumulative trucks). SPL = Sound Pressure Level Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
55 Table 5-6. Summary of test results for Colorado US 287 sections. Construction--No Traffic (all measurements based on testing in right wheelpath) Texture Smooth Friction Noise Design Near Far Groove HS CTM Field Int Field Sect Depth, EMTD, MTD, CTM IRI, DFT SI, L eq , CPB, No. mm mm mm TR in./mi F(60) dB(A) dB(A) dB(A) 3001 0.93 0.88 1.87 (5) 73.5 (2) 52.4 (3) 103.1 (2) 69.7 (3) 77.8 3002 4.8 0.96 1.03 1.26 (1) 92.6 (4) 54.6 (2) 104.3 (4) 70.4 (5) 3003 3.2 1.12 1.08 1.36 (2) 84.9 (3) 56.0 (1) 104.4 (6) 71.4 (6) 3004 3.2 0.80 1.03 1.47 (3) 123.2 (6) 44.4 (5) 104.3 (4) 69.2 (2) 78.6 3005 1.6 0.67 0.91 2.44 (6) 59.7 (1) 43.8 (6) 102.7 (1) 68.1 (1) 3006 3.2 0.92 0.81 1.51 (4) 98.3 (5) 50.7 (4) 103.8 (3) 69.9 (4) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km Note: Values in parentheses represent relative rankings for the respective test parameter. are key observations concerning the performance of these 1004--Long tine, 0.75-in. (19-mm) spacing, 0.15-in. sections: (3.8-mm) depth, turf drag. 1061--Tran groove, 1-in. (25.4-mm) spacing, 0.1875- to Sections with the lowest texture depths (3006 [longitudinal- 0.25-in. (4.8- to 6.4-mm) depth, turf drag. tine-standard groove depth], 3001 [heavy turf drag], and 1007--Long turf drag. 3005 [longitudinal DG]) exhibited the lowest near-field noise levels and friction values in the mid to low range. Table 5-7 summarizes the texture, friction, and noise infor- Sections with the highest texture depths (3002 [longitudinal- mation collected on the sections, including test measurements tine-deeper groove), 3003 [longitudinal meander tine], and made by Iowa DOT at the time of construction (Marks, 1996). 3004 [longitudinal groove]) generally yielded the high- Key observations concerning the performance of these est near-field and interior noise and the highest friction; textures are as follows: the exception being the longitudinal groove texture that exhibited the second lowest friction and the second low- Comparable texture depths were obtained from the high- est interior noise. speed profiler for the five textures. Friction levels on these Comparison of Sections 3006 and 3002 (longitudinal-tine sections were considerably higher than those for other sec- with standard and deeper grooves, respectively) indicated tions, as indicated by the IFI F(60) values derived from the opposite effects of texture depth on friction and noise. FN40S measurements. Also, Section 3003 (longitudinal meander tine with standard The narrower spacing and shallower depth of the tine pro- grooves) resulted in higher texture depth than Section 3006. file in Section 1003 yielded slightly lower near-field and Higher texture ratios corresponded to lower noise levels. interior noise levels than that for Section 1004. Smoothness may have contributed to this trend, as exhib- The longitudinal turf drag (Section 1007) exhibited low ited by Sections 3004 (roughest) and 3005 (smoothest). friction values. Noise spectra identified no tonal issues for any of the The longitudinal turf drag section appeared to be the qui- textures. etest surface initially (for internal noise), but was surpassed by the two longitudinal-tine textures and was assigned a qualitatively "high" noise level. Iowa Sections Transverse-tine and groove textures (Sections 1002 and Sections on US 163. The test sections on US 163 near Des 1061) were assigned qualitatively "high" near-field noise Moines were constructed in fall 1993 and opened to traffic in levels with the latter assigned a qualitatively "high" level for 1994. Texture, friction, and noise measurements were made in interior noise. However, friction levels on both sections August 2005. Descriptions of the test sections are as follows: were considerably lower than those for the longitudinal- tine sections (1003 and 1004). 1002--Tran tine, 0.5-in. (12.7-mm) spacing, 0.075-in. All sections exhibited comparable texture depth deterio- (1.9-mm) depth, turf drag. ration rates, ranging from 0.006 to 0.009 mm per million 1003--Long tine, 0.5-in. (12.7-mm) spacing, 0.075-in. vehicles [0.04 to 0.05 mm per million trucks]. Consider- (1.9-mm) depth, turf drag. ing the snowfall experienced at this location, a portion of

OCR for page 48
Table 5-7. Summary of test results for Iowa US 163 sections. Construction1 Low Traffic (LC)2 High Traffic (WP)3 Texture Friction Noise Texture Smooth Noise Texture Smooth Friction Noise Sect Design Actual Int Near Near No. Groove Groove Noise HS Field Int HS Field Int Depth, Depth, Panel EMTD, IRI, SI, Leq, EMTD, IRI, SI, Leq, mm mm FN40R Rating mm in./mi dB(A) dB(A) mm in./mi FN40S F(60) dB(A) dB(A) 1002 1.9 2.25 52 5.7 (4) 1.12 103.4 105.2 (2) 70.7 (1) 0.98 107.3 36.6 (3) 107.6 (4) 71.7 (2) 1003 1.9 2.50 48 2.4 (2) 1.09 118.9 105.3 (3) 71.1 (2) 0.96 113.8 41.4 (2) 105.6 (1) 71.3 (1) 1004 3.8 4.00 49 3.0 (3) 1.09 125.1 105.9 (4) 72.1 (3) 0.96 134.5 43.3 (1) 106.5 (2) 72.3 (3) 1061 4.8-6.4 1.09 106.8 108.6 (5) 74.1 (4) 1.00 103.9 36.3 (4) 109.4 (5) 74.3 (5) 1007 41 1.6 (1) 1.12 129.0 105.0 (1) 71.1 (2) 1.01 126.6 17.8 (5) 106.6 (3) 73.1 (4) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Measurements by Iowa DOT. 2 Estimated 158,000 cumulative vehicles (12,600 cumulative trucks). 3 Estimated 15,800,000 cumulative vehicles (2,500,000 cumulative trucks). Note 1: Values in parentheses represent relative rankings for the respective test parameter. Note 2: Panel rating for interior noise based on 1-to-10 scale (1=unobjectionable, 10=very objectionable)

OCR for page 48
57 these texture deterioration rates could be the result of friction, and noise measurements were made in September, frequent snowplow use. 2005. Descriptions of the seven test sections are as follows: Sections 1002 and 1003 exhibited definite tonal spikes around 1,500 Hz, indicative of high-frequency whine. 1002--Long DG (no jacks), 0.235-in. (6-mm) spacing (i.e., 0.11-in. [2.8-mm] spacers), standard-sawed joints. Sections on US 34. The test sections on US 34 Bypass north 1004--Long DG (no jacks), 0.245-in. (6.2-mm) spacing of Mt. Pleasant were constructed in fall 2004. Texture, friction, (i.e., 0.12-in. [3.0-mm] spacers), single-sawed joints. and noise measurements were made just prior to opening to 1005--Long DG (jacks), 0.255-in. (6.5-mm) spacing traffic in fall 2005 (DF Tester and CT Meter testing was per- (i.e., 0.13-in. [3.3-mm] spacers), standard-sawed joints. formed about 6 months later in 2006). The two test sections 1006--Long DG (jacks), 0.255-in. (6.5-mm) spacing are described as follows: (i.e., 0.13-in. [3.3-mm] spacers), single-sawed joints. 1007--Long DG (no jacks), 0.255-in. (6.5-mm) spacing 2001--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. (i.e., 0.13-in. [3.3-mm] spacers), standard-sawed joints. (3.2-mm) depth), turf drag. 1008--Long DG (no jacks), 0.255-in. (6.5-mm) spacing 2002--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. (i.e., 0.13-in. [3.3-mm] spacers), single-sawed joints. (3.2-mm) depth, burlap drag. 1010--Long tine, 0.75-in. (19-mm) spacing, 0.15-in. (3.8-mm) depth, turf drag. Table 5-8 summarizes the texture, friction, and noise data collected on the two sections. Some key observations concern- Table 5-9 summarizes the texture, friction, and noise infor- ing the performance of these sections are as follows: mation collected on the test sections, including measurements made by others (Brennan and Schieber, 2006) at the time of The slightly lower texture depth in Section 2001 appears to construction. Key observations concerning the performance have contributed to lower near-field and interior noise on of these sections are as follows: this section than on Section 2002. The more aggressive pre-texturing associated with turf The consistently higher texture depths for the four diamond- drag on Section 2001 has likely resulted in higher friction ground surfaces with 0.13-in. [3.3-mm] spacers resulted in levels on this section than on the other. moderately high rankings for friction and moderately low Smoothness levels of the two sections are very similar, and rankings for noise. Despite the low cumulative traffic, nearly thus smoothness was not a contributing factor to the dif- all sections reached qualitatively "high" levels of interior ferent levels in noise. noise. Specific comparisons of spacer widths (Section 1002 Noise spectra identified no tonal issues for any of the versus 1007 and Section 1004 versus 1008) show that wider textures. blade spacing contributes to higher texture depth, higher friction, slightly to moderately higher near-field noise, higher interior noise, and greater roughness. Kansas Sections The effect of using jacks in the diamond grinding process The test sections on US 69 near Louisburg were con- was not particularly noticeable. Comparisons of Sections structed in 2004 and opened to traffic in late 2004. Texture, 1005 and 1007 and Sections 1006 and 1008 revealed slight Table 5-8. Summary of test results for Iowa US 34 sections. Construction (measurements based on testing in right wheelpath, unless indicated differently) Texture Smooth Friction Noise Design Near Far Groove HS CTM Field Int Field Sect Depth, EMTD, MTD, CTM IRI, DFT SI, L eq , CPB, No. mm mm mm1 TR1 in./mi F(60)1 FN40S F(60) dB(A) dB(A) dB(A) 2001 3.2 0.80 LC=0.73 LC=1.27 88.5 (2) LC=27.8 52.9 (1) 103.8 (1) 71.5 (1) 78.5 WP=0.66 WP=1.34 WP=26.9 2002 3.2 0.89 LC=0.80 LC=1.14 88.0 (1) LC=26.5 51.1 (2) 105.3 (2) 72.8 (2) 80.5 WP=0.71 WP=1.13 WP=26.1 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Testing with CT Meter and DF Tester performed approximately 6 months after facility opened to traffic. Estimated 750,000 cumulative vehicles applied to wheelpath and 7,500 cumulative vehicles applied to lane center (67,000 and 350 cumulative trucks). Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
Table 5-9. Summary of test results for Kansas US 69 sections. 1 2 3 Construction Low Traffic (LC) High Traffic (WP) Texture Smooth Friction Noise Texture Smooth Friction Noise Texture Smooth Friction Noise Design Sand Ames Near Near Near Sect Groove Patch LP Field HS CTM Field Int HS CTM Field Int No. Depth, MTD, IRI, SI, EMTD, MTD, CTM IRI, DFT SI, L eq , EMTD, MTD, CTM IRI, DFT SI, L eq , mm mm in./mi FN40R dB(A) mm mm TR in./mi F(60) dB(A) dB(A) mm mm TR in./mi F(60) dB(A) dB(A) 1002 1.6 1.04 46.0 (6) 49.7 (7) 103.3 (1) 0.62 0.86 2.16 (6) 50.5 (1) 32.9 (7) 104.3 (1) 71.9 (1) 0.64 0.85 2.14 (2) 46.6 (1) 30.2 (7) 105.0 (1) 72.5 (1) 1004 1.6 1.14 37.2 (1) 51.5 (5) 103.5 (2) 0.68 0.85 2.22 (7) 60.5 (3) 34.4 (5) 105.0 (3) 72.6 (3) 0.71 0.88 2.37 (7) 63.5 (5) 32.3 (6) 106.0 (6) 72.5 (1) 1005 1.6 1.32 43.9 (4) 60.7 (1) 105.1 (5) 0.71 1.03 2.11 (3) 63.6 (5) 35.6 (3) 105.0 (3) 72.8 (5) 0.71 1.00 2.14 (2) 60.7 (2) 33.9 (4) 105.6 (4) 72.7 (3) 1006 1.6 1.45 40.1 (3) 57.1 (2) 105.2 (6) 0.69 1.04 2.10 (2) 63.5 (4) 35.3 (4) 105.0 (3) 72.5 (2) 0.72 1.01 2.16 (4) 62.5 (4) 33.2 (5) 105.8 (5) 72.8 (4) 1007 1.6 1.45 37.4 (2) 56.4 (3) 105.0 (4) 0.68 0.99 2.15 (5) 60.0 (2) 33.9 (6) 104.9 (2) 72.6 (3) 0.71 1.10 2.28 (6) 61.6 (3) 34.3 (3) 105.3 (2) 73.3 (5) 1008 1.6 1.30 44.2 (5) 55.1 (4) 104.2 (3) 0.87 0.95 2.12 (4) 96.7 (6) 39.2 (1) 105.9 (7) 73.7 (7) 0.92 1.00 2.23 (5) 99.6 (7) 38.7 (1) 106.9 (7) 74.5 (7) 1010 4.8 0.56 102.6 (7) 50.8 (6) 108.2 (7) 0.64 0.74 1.26 (1) 105.7 (7) 36.3 (2) 105.3 (6) 73.0 (6) 0.66 0.71 1.19 (1) 94.8 (6) 35.6 (2) 105.4 (3) 73.8 (6) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km CPB Noise Measurements: Sect 1004 (77.8 dB(A)) 1 Measurements by Kansas DOT. 2 Estimated 15,000 cumulative vehicles (1,500 cumulative trucks). 3 Estimated 1,500,000 cumulative vehicles (300,000 cumulative trucks). Three different testing devices--CA Profilograph, SD Profilometer, and Ames Lightweight Profiler (LP)--were used to measure smoothness, each giving different results. For consistency purposes, Ames LP IRI measurements are listed. Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
Table 5-11. Summary of test results for North Dakota I-94 test sections. 1 2 3 Construction Low Traffic (LC) High Traffic (WP) Texture Friction Noise Texture Smooth Friction Noise Texture Smooth Friction Noise Sect Design Sand Near Near No. Groove Patch Int HS CTM Field Int HS CTM Field Int Depth, MTD, Noise, EMTD, MTD, CTM IRI, DFT SI, L eq , EMTD, MTD, CTM IRI, DFT SI, Leq, mm mm FN40R dB(A) mm mm TR in./mi F(60) dB(A) dB(A) mm mm TR in./mi F(60) dB(A) dB(A) 2001 0.90 43.0 (1) 68.1 (1) 0.91 0.67 1.23 (1) 80.5 (1) 47.9 (1) 109.8 (2) 72.4 (2) 0.88 0.64 1.21 (1) 93.0 (1) 39.6 (1) 110.8 (2) 73.8 (2) 2002 2.5 1.00 40.2 (2) 69.5 (2) 0.69 0.47 1.78 (2) 81.0 (2) 40.8 (2) 104.8 (1) 68.7 (1) 0.69 0.47 1.76 (2) 98.9 (2) 36.6 (2) 106.2 (1) 69.0 (1) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km 1 Measurements by North Dakota DOT. 2 Estimated 45,000 cumulative vehicles (6,500 cumulative trucks). 3 Estimated 4,500,000 cumulative vehicles (1,300,000 cumulative trucks). Note: Values in parentheses represent relative rankings for the respective test parameter.

OCR for page 48
62 million trucks) for the heavy turf drag (Section 2001). Longitudinal grooved sections (7 and 8) were among the Despite no change in texture depth on Section 2002, fric- quietest textures, despite the relatively high texture depths. tion has decreased and noise has increased somewhat. Negative texture orientation (TR<0.9) may have con- Noise spectra identified no tonal issues for any of the tributed to this phenomenon. The higher texture depth of textures. Section 8 resulted in significantly greater friction than for Section 7. Performance of longitudinal-tine sections (2, 5a, 5b, and 6) Illinois Tollway I-355 South Extension Newly Constructed Sections varied. The section with the highest macro-texture (Sec- tion 5b), due in part to the heavy turf drag pretexture, had The test sections at the Illinois Tollway were constructed in the greatest levels of friction and roughness. Section 5a, April/May and September/October 2007 and opened to traf- which used normal turf drag pretexture, had much lower fic in November 2007. Texture, friction, and noise measure- friction and near-field noise, but similar interior noise. ments were made 1 to 3 months prior to opening. Texture Section 2, which included no pretexture, also showed measurements included tine depth readings taken with a significantly less friction and noise. Standard- and shallow- depth gauge (1) during construction, immediately behind the depth longitudinal tining Sections 5a and 6 indicated sim- tining machine, (2) after a few weeks of construction traffic, ilar levels of friction and near-field noise, but considerably and (3) several weeks after construction and before opening lower interior noise for the latter. to traffic. Descriptions of the textures are again as follows: The diamond-ground Section 3 exhibited the lowest near- field and interior noise levels and its texture depth was 1a--Long heavy turf drag. fourth highest among all sections. 1b--Long heavy turf drag (modified). Friction performance of the transverse tine sections was 2--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. (3.2-mm) about the same as that for the longitudinal-tine section. The depth, no pretexture. near-field noise levels for these textures were somewhat 3--Long DG (no jacks), 0.235-in. (6-mm) spacing (i.e., higher than those for the longitudinal, but the interior noise 0.11-in. [2.8-mm] spacers), no pretexture. levels were slightly lower. 5a--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. Two transverse tine sections were found to have significant (3.2-mm) depth, turf drag. tonal spikes in the noise spectra. Section 9 (Georgia design 5b--Long tine, 0.75-in. (19-mm) spacing, 0.125-in. with 0.5-in. [12.7-mm] spacing) showed a spike around (3.2-mm) depth, heavy turf drag. 1,600 Hz, and Section 11 (old ISTHA design with 1.0-in. 6--Long tine, 0.75-in. (19-mm) spacing, 0.075-in. (2-mm) [25.4-mm] spacing) showed a spike around 1,000 Hz. depth, turf drag. Roughness may have contributed to the noise generated by 7--Long groove, 0.75-in. (19-mm) spacing, 0.25-in. longitudinal-tine on Sections 2 and 5b and by transverse (6.4-mm) depth, burlap drag. tine on Section 11. 8--Long groove, 0.75-in. (19-mm) spacing, 0.25-in. (6.4-mm) depth, turf drag. 9--Tran tine, 0.5-in. (12.7-mm) spacing, 0.125-in. General Observations (3.2-mm) depth, burlap drag (GA design). 10--Tran tine, variable spacing, 0.125-in. (3.2-mm) depth, Diamond Grinding burlap drag. Jacks versus no jacks--No notable differences observed 11--Tran tine, 1.0-in. (25.4-mm) spacing, 0.125-in. at the sites in Arizona and Kansas. (3.2-mm) depth, burlap drag (old ISTHA design). TR--Typical values for diamond-ground sections ranged 12--Tran skewed tine, variable spacing, 0.125-in. from 1.5 to 2.5, which exceeded the desirable range (3.2-mm) depth, turf drag (new ISTHA design). (<0.9 to 0.95) for "negative" texture orientation. In gen- eral, a lower TR of the diamond grind texture results in Table 5-12 summarizes the texture, friction, and noise infor- a lower noise level. mation collected on these sections. Key observations concern- Grinding versus Grooving--Although texture depths of ing the performance of these textures are as follows: ground sections in California and Colorado (US 287 [untraf- ficked]) were consistently lower than grooved sections, noise Turf drag sections (1a and 1b) exhibited the lowest texture results varied (higher noise on California sites and slightly depths and lowest levels of friction. Near-field noise was lower noise on Colorado sites). Friction levels for the ground relatively low compared with most other surfaces, but sections at both locations were slightly lower than that for the interior noise was ranked high. grooved sections.

OCR for page 48
Table 5-12. Summary of test results for Illinois Tollway newly constructed test sections. Construction--No Traffic (all measurements based on testing in right wheelpath) Texture Smooth Friction Noise Groove Groove Design Depth Depth CTM Near Far Sect Groove Behind After Const Groove HS CTM Field Int Field No. Depth, Tiner, Traffic, Depth, EMTD, MTD, CTM PI0.0, IRI, DFT SI, L eq , CPB, mm mm mm mm mm mm TR in./mi in./mi F(60) FNS F(60) FNR F(60) dB(A) dB(A) dB(A) 1a 0.51 21.2 (6) 76 (8) 23.5 (7) 30.6 (8) 101.7 (3) 69.5 (10) 1b 0.59 0.54 1.88 16.3 (1) 63 (3) 21.2 (11) 24.3 (8) 32.1 (5) 101.8 (4) 69.1 (8) 79.3 (6) 2 3.2 3.21 2.63 2.54 0.74 0.65 1.15 22.9 (9) 92 (9) 23.0 (8) 32.8 (6) 30.0 (13) 103.3 (11) 69.5 (10) 79.5 (7) 3 1.5 1.21 0.48 0.74 2.41 20.1 (3) 40 (1) 22.3 (9) 36.0 (3) 100.6 (1) 67.6 (1) 77.5 (1) 5a 3.2 3.00 2.53 2.69 0.63 0.48 1.27 21.1 (5) 70 (7) 21.6 (10) 35.2 (3) 32.0 (6) 102.5 (6) 71.1 (12) 77.6 (2) 5b 3.2 2.96 1.18 1.05 1.31 27.5 (12) 111 (12) 30.6 (2) 42.7 (1) 30.2 (10) 105.6 (13) 72.0 (13) 82.4 (12) 6 1.9 2.16 1.89 1.94 0.64 0.52 1.33 21.9 (8) 69 (6) 19.5 (13) 34.1 (5) 30.2 (10) 102.3 (5) 68.4 (6) 78.7 (3) 7 6.4 3.61 0.86 0.84 0.73 31.6 (13) 139 (13) 29.4 (3) 30.1 (12) 101.5 (2) 68.1 (5) 79.1 (5) 8 6.4 5.26 0.99 1.40 0.75 17.9 (2) 106 (11) 36.4 (1) 36.5 (2) 102.5 (6) 68.0 (4) 78.3 (4) 9 3.2 3.11 2.68 2.08 0.58 0.59 1.57 20.5 (4) 55 (2) 24.0 (4) 30.6 (8) 102.7 (9) 67.7 (2) 80.7 (10) 10 3.2 3.06 2.50 2.11 0.70 0.71 1.45 25.7 (11) 67 (5) 23.8 (5) 37.2 (2) 39.2 (1) 102.8 (10) 68.8 (7) 81.2 (11) 11 3.2 2.83 0.62 0.50 1.08 25.6 (10) 101 (10) 20.5 (12) 35.2 (3) 32.7 (4) 104.2 (12) 69.3 (9) 80.3 (9) 12 3.2 3.00 2.63 2.37 0.47 0.66 1.42 21.4 (7) 64 (4) 23.8 (5) 28.7 (7) 31.9 (7) 102.5 (6) 67.8 (3) 80.1 (8) 1 in. = 25.4 mm 1 in./mi = 15.78 mm/km

OCR for page 48
64 Grinding versus Longitudinal Tining--Diamond-ground souri Section 1001, respectively) and two 0.75-in. (19-mm) sections in Colorado (US 287 [untrafficked]) and Kansas spacing designs with standard depths (Iowa Sections 8001 have resulted in lower levels of friction and interior noise and 8002) were found to have notable tonal issues. regardless of the texture depth than the longitudinally tined sections. Near-field noise levels for the ground sections have Texture Durability Analysis ranged from considerably lower to slightly higher than the Micro-Texture Deterioration tined sections. Grooving versus Longitudinal Tining--Colorado I-70 and Figure 5-17 provides an indication of the durability of US 287 (untrafficked) sections showed a slight increase in micro-texture for the different sites/locations, based on texture depth of grooved textures resulting in similar to DFT(20) friction values obtained by the DF Tester in the lower levels of friction, slightly lower interior noise, and wheelpath and lane center. Best-fit logarithmic functions slightly lower to slightly higher near-field noise. were derived to determine the trends as a function of traffic Turf, Broom, and Burlap Drags--These textures will incur (by state). Although the number and types of textures at each friction problems and may develop noise issues, if high tex- site are not the same, and the type(s) of aggregate used in the ture is not provided and/or high-quality aggregate is not concrete mix were not known for all sites, the data illustrate the used. If studded tires are not used, drag textures generally importance of using high-quality aggregate to maintain high provide the lowest texture deterioration rates under traffic, levels of friction over time/traffic. For instance, in Colorado and possibly under snowplows. where high-silica granite was used and in Minnesota where a Effect of Smoothness on Noise--Most sections exhibited granite was also used, the initial average DFT(20) values were high or moderately high levels of smoothness (IRI less than high and remained high under large amounts of traffic. Use of 90 to 100 in./mi), but the effect of roughness could not be limestone in Kansas and Illinois, on the other hand, has resulted determined. in greater rates of micro-texture deterioration. One longitudinal-tine section located in Iowa and transverse Based on the available information concerning the types of tine textures with two 0.5-in. (12.7-mm) spacing designs aggregates that were used in the concrete at the various and shallow or standard depths (Iowa Section 1002 and Mis- sites/locations, it is apparent that use of higher quality aggre- AZ SR202L CA SR58 CO I-70 IL I-55/74 KS US69 MN US169 MO US36 ND I-94 TX I-20 Wi US151 Log. (MN US169) Log. (MO US36) Log. (ND I-94) Log. (AZ SR202L) Log. (CO I-70) Log. (IL I-55/74) Log. (KS US69) Log. (CA SR58) Log. (TX I-20) Log. (W i US151) 90.0 85.0 80.0 (WI) DFT(20) = -1.0564Ln(Traf) + 78.691 (AZ) DFT(20) = -0.9548Ln(Traf) + 76.23 9 75.0 (CO) DFT(20) = -1.6367Ln(Traf) + 76.613 CO (fine agg) High-silica granite MN (fine agg) Granite 70.0 (MN) DFT(20) = -2.2786Ln(Traf) + 77.38 3 DFT(20) (ND) DFT(20) = -2.487 6Ln(Traf) + 75.058 65.0 (IL) DFT(20) = -3.7523Ln(Traf) + 71.151 IL (fine agg) Blend of manufactured sand (limestone) and natural sand (CA) DFT(20) = -2.9996Ln(Traf) + 68.499 60.0 (MO) DFT(20) = -1.4136 Ln(Traf) + 64.977 55.0 (KS) DFT(20) = -0.7385L n(Traf) + 62.082 KS (coarse agg) Limestone 50.0 45.0 (TX) DFT(20) = -1.0604Ln(Traf) + 47.066 40.0 0 10 20 30 40 50 60 70 Cumulative Traffic, million vehicles Figure 5-17. Micro-texture versus cumulative combined traffic.

OCR for page 48
65 AZ SR 202L CA SR 58 KS US 69 Lo g. (AZ SR 202L) Lo g. (C A SR 58) Lo g. (KS US 69) 2.00 1.80 1.60 1.40 CTM MTD, mm 1.20 (AZ) MTD = 0.0328Ln(Traf) +1.5888 R 2 = 0.055 1.00 (KS) MTD = 0.0043Ln(Traf) + 0.9116 0.80 R 2 = 0.0154 0.60 (C A) MTD = -0.0499Ln(Tra f) + 1.4742 0.40 R 2 = 0.9363 0.20 0.00 0 5 10 15 20 25 30 35 40 Cumulative Traffic, million vehicles Figure 5-18. Macro-texture versus cumulative combined traffic for diamond-ground sections. gates in the concrete mixture helps to maintain the micro- Meter MTD values (or in some cases, high-speed profiler texture qualities needed for friction. EMTD values) taken in the wheelpath and lane center. Best- fit logarithmic functions were derived for each data set. These figures illustrate the reduction in texture depth for Macro-Texture Deterioration each texture type. With the exception of some of the sections in Figures 5-18 through 5-23 show the rates of deterioration Kansas, which showed greater texture depth in the wheelpath in macro-texture for the different texture types based on CT than in the lane center (possibly because of wear caused by CA SR 58 CO I-70 Lo g. (C A SR 58) Lo g. (CO I-70) 1.80 1.60 (CO) MTD = 0.0239Ln(Traf) + 1.0162 R2 = 1 1.40 (CA) MTD = 0.005Ln(Traf) + 1.3916 R2 = 0.0033 1.20 CTM MTD, mm 1.00 0.80 0.60 0.40 0.20 0.00 0 5 10 15 20 25 30 35 40 Cumulative Traffic, million vehicles Figure 5-19. Macro-texture versus cumulative combined traffic for longitudinal grooved sections.

OCR for page 48
66 IL I-55/74 & I-70 IA US 163 & US 218 MO US 36 WI US 151 ND I-94 Log. (IL I-55/74 & I-70) Log. (IA US 163 & US 218) Log. (MO US 36) Log. (WI US 151) Log. (ND I-94) 1.20 (IA) MTD = -0.017Ln(Traf) + 1.2563 CTM MTD or HS EMTD, mm 1.00 R2 = 0.3175 (IL) MTD = -0.0128Ln(Traf) + 1.0457 R 2 = 0.0452 0.80 (WI) MTD = 0.0261Ln(Traf) + 1.2054 R2 = 1 (ND) MTD = 0.0083Ln(Traf) + 0.806 R2 = 0.1433 0.60 (MO) MTD = -0.013Ln(Traf) + 0.8636 R2 = 1 0.40 0.20 0.00 0 5 10 15 20 25 30 35 40 Cumulative Traffic, million vehicles Figure 5-20. Macro-texture versus cumulative combined traffic for transverse tine sections. snowplows in the lane center), upwards of 0.012 in. (0.3 mm) sections showed only slight amounts of loss (0.002 to 0.003 in. of loss over the first 10 million applications of traffic occurred. [0.05 to 0.08 mm]). Considerably lower losses of the longitudinal and transverse As Figure 5-23 shows, the shotblasted section in Texas and tine textures (0.004 to 0.005 in. [0.1 to 0.12 mm]) were experi- an asphalt-surfaced section in Illinois exhibited greater texture enced. With the exception of a turf drag section in Iowa (Sec- depth in the wheelpath than in the lane center. Snowplow tion 1007), the drag and the longitudinal-grooved textured operations may have been a factor for the sections in Illinois CO I-70 IA US 163 KS US 69 MN US 169 Log. (CO I-70) Log. (IA US 163) Log. (KS US 69) Log. (MN US 169) 1.20 (IA) MTD = 0.0261Ln(Traf) + 1.4019 (MN) MTD = 0.0184Ln(Traf) + 1.2812 R 2 = 0.9863 R 2 = 0.269 1.00 CTM MTD or HS EMTD, mm (CO) MTD = -0.0152Ln(Traf) + 1.1106 0.80 R2 = 1 (KS) MTD = 0.0065Ln(Traf) + 0.8026 R2 = 1 0.60 0.40 0.20 0.00 0 10 20 30 40 50 60 70 80 Cumulative Traffic, million vehicles Figure 5-21. Macro-texture versus cumulative combined traffic for longitudinal-tine sections.

OCR for page 48
67 CA SR 58 CO I-70 IA US 163 MN US 169, I-94/494, & I-694 ND I-94 Log. (ND I-94) Log. (MN US 169, I-94/494, & I-694) Log. (IA US 163) Log. (CO I-70) Log. (CA SR 58) 1.20 (IA) MTD = -0.0304Ln(Traf) + 1.5039 CTM MTD or HS EMTD, mm 1.00 R2 = 1 0.80 (ND) MTD = -0.0065Ln(Traf) + 0.7398 (MN) MTD = 0.0031Ln(Traf) + 0.5414 R2 = 1 R 2 = 0.1109 0.60 (CA) MTD = 0.0035Ln(Traf) + 0.3018 0.40 R 2 = 0.5563 (CO) MTD = -0.0065Ln(Traf) + 0.4474 R2 = 1 0.20 0.00 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 Cumulative Traffic, million vehicles Figure 5-22. Macro-texture versus cumulative combined traffic for longitudinal drag sections. but not for the sections in Texas. The other asphalt-surfaced lished and the effect of climate on texture loss could not be textures exhibited losses between 0.002 and 0.004 in. [0.05 and determined. However, locations with significant freeze-thaw 0.1 mm]) after 20 million vehicle applications; an ultra-thin cycles, frequent snowfall events (and thus frequent snowplow bonded wearing course section in Kansas had nearly 0.008 in. use) and/or considerable studded tire use are expected to (0.2 mm) loss after 2.5 million vehicle applications. experience greater texture loss; one study has confirmed this Because of the very limited number of test sections of each trend for diamond-ground pavements (Rao et al., 1998). In texture type, a time-series for MTD data could not be estab- this study, test data from 36 diamond-ground pavements in ILAC (Superpave) ILAC TX Shotblast Iowa AC (Superpave) NC Novachip KS Novachip Log. (ILAC) Log. (IL AC (Superpave)) Log. (Iowa AC (Superpave)) Log. (NC Novachip) Log. (KS Novachip) Log. (TX Shotblast) 1.20 CTM MTD or HS EMTD, mm 1.10 (IA AC Superpave) MTD = -0.0195Ln(Traf) + 1.3239 R2 = 1 1.00 (KS NovaChip) MTD = -0.0651Ln(Traf) + 0.9146 R2 = 1 0.90 (NC Novachip) MTD = -0.0195Ln(Traf) + 1.1378 R2 = 1 (TX Shotblast) MTD = 0.0109Ln(Traf) + 0.7695 0.80 R2 = 1 0.70 (ILAC) MTD = -0.0109Ln(Traf) + 0.9174 0.60 (IL AC SuperPave) MTD = 0.0065Ln(Traf) + 0.4886 R2 = 1 R2 = 1 0.50 0.40 0 5 10 15 20 25 30 35 Cumulative Traffic, million vehicles Figure 5-23. Macro-texture versus cumulative combined traffic for miscellaneous textures.

OCR for page 48
68 14 states were used to model texture depth over time. The testing was performed for the following three basic traffic resulting model showed freezing environments as a contribut- levels: ing factor in the deterioration of texture over time and pro- jected a texture depth loss of 0.016 to 0.020 in. (0.4 to 0.5 mm) No traffic--Post-construction testing, prior to opening of for nonfreezing and freezing climates, respectively, after 5 years facility to traffic. following grinding. Low traffic--Lane center test measurement, less than In summary, the loss of macro-texture over time/traffic 5,000,000 cumulative vehicles and/or less than 500,000 appears to be greatest for diamond-ground textures and cumulative trucks. lowest for longitudinally grooved and dragged textures. The High traffic--Wheelpath test measurement, greater than geometric shape (i.e., narrow fins) of the diamond ground 5,000,000 cumulative vehicles and/or greater than 500,000 texture results in more substantial loss than textures with no cumulative trucks. grooves (drag textures) or those that have well-defined, widely spaced, and structurally sound grooves (longitudinal groove textures). Figures 5-24 through 5-30 show noise ranges that are used to qualitatively assess the noise levels exhibited by each gen- Noise Comparison eral texture type. The noise ranges are designated as levels A through E and are defined in Table 5-13. Noise Performance by General Texture Type Although many factors (e.g., texture characteristics, climate, For this analysis, the 57 existing and 13 newly constructed traffic, and pavement condition) influence the results shown in test sections were grouped into the following seven categories these figures, some general trends regarding the qualitative based on general texture type: noise performance over time/traffic can be seen, as summa- rized in Table 5-14. The tonal whines identified previously for some of the textures (primarily transverse-tine sections) were Longitudinal drag (i.e., burlap, broom, or turf). not considered in these assessments. Transverse tine (i.e., straight, skewed, uniformly spaced, or Diamond-ground and grooved textures showed the lowest variably spaced). initial noise levels, followed by longitudinal drag, longitudinal- Longitudinal tine (i.e., straight or meandering). tine, and transverse-tine textures. Asphalt surfaces exhibited Diamond ground. the lowest long-term noise, followed closely by the diamond- Longitudinal grooved. ground and grooved textures and longitudinal tining. EAC, Miscellaneous textures (e.g., transverse groove, EAC, and shotblasted PCC, and transverse grooving exhibited the high- shotblast). est long-term noise. Asphalt (i.e., HMA, ultra-thin bonded wearing course). Most sections showed an increase in noise, but some showed virtually no change in noise over time/traffic (i.e., lane cen- Near-field SI and interior noise data (mean 1 standard ter versus wheelpath measurements). These noise increases deviation) for all the sections constituting each category were occurred despite reductions in texture depth, probably plotted sequentially according to the basic time at which the because of changes in texture orientation and spectral makeup, 112.0 75.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 111.0 74.0 110.0 73.0 Interior Noise Leq, dBA 109.0 Near-Field SI, dBA 72.0 108.0 107.0 71.0 106.0 70.0 105.0 69.0 104.0 68.0 103.0 67.0 102.0 101.0 66.0 100.0 65.0 No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-24. Noise levels for longitudinal drag textures.

OCR for page 48
69 110.0 75.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 109.0 74.0 108.0 73.0 Interior Noise Leq, dBA Near-Field SI, dBA 107.0 72.0 106.0 71.0 105.0 70.0 104.0 69.0 103.0 68.0 102.0 67.0 101.0 66.0 100.0 65.0 No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-25. Noise levels for transverse tine textures. 110.0 75.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 109.0 74.0 108.0 Interior Noise Leq, dBA 73.0 72.0 Near-Field SI, dBA 107.0 106.0 71.0 105.0 70.0 104.0 69.0 103.0 68.0 102.0 67.0 101.0 66.0 100.0 65.0 No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-26. Noise levels for longitudinal-tine textures. 110.0 75.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 109.0 74.0 108.0 73.0 Interior Noise Leq, dBA Near-Field SI, dBA 107.0 72.0 106.0 71.0 105.0 70.0 104.0 69.0 103.0 68.0 102.0 67.0 101.0 66.0 100.0 65.0 NoTraffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-27. Noise levels for diamond-ground textures.

OCR for page 48
70 110.0 75.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 109.0 74.0 108.0 73.0 Interior Noise Leq, dBA Near-Field SI, dBA 107.0 72.0 106.0 71.0 105.0 70.0 104.0 69.0 103.0 68.0 102.0 67.0 101.0 66.0 100.0 65.0 NoTraffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-28. Noise levels for longitudinal grooved textures. Tran Groove Shotblast Tran Groove EAC Shotblast Tran Groove Shotblast Tran Groove EAC Shotblast 110.0 75.0 109.0 74.0 108.0 73.0 Interior Noise Leq, dBA Near-Field SI, dBA 107.0 72.0 106.0 71.0 105.0 70.0 104.0 69.0 103.0 68.0 102.0 67.0 101.0 66.0 Bars represent Mean 1 Std Dev Bars represent Mean 1 Std Dev 100.0 65.0 NoTraffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-29. Noise levels for miscellaneous textures. 110.0 75.0 HMA NovaChip HMA NovaChip Bars represent Mean 1 Std Dev 109.0 74.0 108.0 73.0 Interior Noise Leq, dBA HMA NovaChip Near-Field SI, dBA 107.0 72.0 106.0 71.0 105.0 70.0 104.0 HMA 69.0 103.0 68.0 102.0 67.0 101.0 66.0 Bars represent Mean 1 Std Dev 100.0 65.0 NoTraffic (Post Const) Low Traffic (LC) High Traffic (WP) No Traffic (Post Const) Low Traffic (LC) High Traffic (WP) (a) Near-Field Noise (b) Interior Noise Figure 5-30. Noise levels for asphalt surface textures.

OCR for page 48
71 Table 5-13. Noise ranges for qualitative assessment of noise. Noise Level Description Near-Field SI Range, dB(A) Interior L eq Range, dB(A) A Low < 102.0 < 67.5 B Fairly Low 102.0 to 104.0 67.5 to 70.0 C Moderate 104.0 to 106.0 70.0 to 72.5 D Fairly High 106.0 to 108.0 72.5 to 75.0 E High > 108.0 >75.0 Table 5-14. Qualitative noise level performance trends for different textures. Texture Near-Field SI Noise Level Interior L eq Noise Level Category Initial Long-Term Initial Long-Term Long Drag B D B C Tran Tine B D B C Long Tine B/C C/D B/C C Long DG A/B/C C A/B B/C Long Groove A/B C A/B B/C Misc. PCC D/E C/D Asphalt B B/C increased distress and/or roughness, or increased joint/joint seal opposite (see Figure 5-31). In all cases, however, the tex- degradation. ture with the lower texture depth produced lower noise. Longitudinal Groove Effect of groove spacing--Data from California indi- Effect of Texture Dimensions on Noise Performance cated that increased spacing (0.75 in. versus 0.375 in. With several texture designs included in each of the seven [19 mm versus 9.5 mm]) results in lower interior noise texture categories, the following effects of texture dimensions and slightly lower near-field noise. (e.g., groove spacing and depth) on near-field SI and interior Effect of groove depth--Data from California indicated Leq noise were observed: that increased depth (0.25 in. versus 0.125 in. [6.4 mm versus 3.2 mm]) results in greater near-field and interior Diamond Grind noise. Effect of spacer widths--Conflicting results were Longitudinal Tine observed. For example, sections in Arizona showed Effect of tine depth--Data from Colorado indicated that lower noise and friction associated with wider spacings, increased depth (0.1875 in. versus 0.125 in. [4.8 mm and sections in California and Kansas indicated the versus 3.2 mm]) results in greater near-field and interior AZ 1002/1004 LC AZ 1002/1004 WP CA 1002/1005 LC AZ 1002/1004 LC AZ 1002/1004 WP CA 1002/1005 LC CA 1002/1005 WP KS 1002/1007 LC KS 1002/1007 WP CA 1002/1005 WP KS 1002/1007 LC KS 1002/1007 WP KS 1004/1008 LC KS 1004/1008 WP KS 1004/1008 LC KS 1004/1008 WP 108 75 74 107 Near-Field SI, dBA 73 Int Noise, dBA 106 72 105 71 70 104 69 103 68 102 67 0.1 0.11 0.12 0.13 0.14 0.1 0.11 0.12 0.13 0.14 Spacer Width, in. Spacer Width, in. (a) Near-Field Noise (b) Interior Noise Figure 5-31. Effect of diamond grind spacer width on noise.