Evaluating Pavement Strategies and Barriers for Noise Mitigation (2013) / Chapter Skim
Currently Skimming:
Pages 7-20
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 7... ...
7 Overview of New Elements In the early stages of this research, concepts for the analysis of the features of pavement strategies and barriers used for noise mitigation were developed. One of the primary elements of the analysis process was the use of OBSI measurements to provide quantification of pavement performance as it relates to traffic noise initially and over the life of the pavement.
|
From page 8... ...
8pavement over time. Three AASHTO standard methods of test are currently available for evaluating the noise performance of the pavements: the Continuous-Flow Traffic Time-Integrated Method (CTIM)
|
From page 9... ...
9 in Figure 2 for a transversely tined PCC pavement prior to and after the application of an asphalt rubber friction course (ARFC)
|
From page 10... ...
10 variations are normalized by comparing the results of controlled pass-by levels to the OBSI levels (3)
|
From page 11... ...
11 vehicles for pavements with OBSI levels between 96 and 97 dBA would average about 7 dB lower than TNM Average Pavement but about 3 dB higher than TNM Average Pavement for pavements with the OBSI levels around 107 dBA. Thus, the total difference in traffic noise levels for these two cases would be about 10 dB.
|
From page 12... ...
12 noise at this speed may be slightly less influenced by pavement changes than light vehicles. For these results, the REMEL values for TNM Average Pavement corresponds to an OBSI level of 103.6 dBA ± 0.9 dB, which is in the same range as that for light vehicles.
|
From page 13... ...
13 pavements because the lower levels of the ARFC are more closely represented and distinction between the two PCC textures is captured. For medium and heavy trucks, the TNM pavement-type averages provide even smaller distinctions between pavement types than for light vehicles (10)
|
From page 14... ...
14 an OBSI level of 102.7 dBA. For the 100 ft receptor distance (Figure 8)
|
From page 15... ...
15 addition, there are a variety of methods by which pavement noise performance can be included in the predicted levels. Within TNM, averages for the three different pavement types developed in the REMEL database are incorporated in the PCC, DGAC, and OGAC Average Pavements.
|
From page 16... ...
16 level for a "quieter pavement" is not defined. To maintain its absolute performance, the pavement will most likely need to be rehabilitated on a shorter cycle than would normally be required for a pavement that is not intended to provide noise mitigation.
|
From page 17... ...
17 The assumed traffic flow includes a daytime hourly average in traffic volume of 8,000 vehicles with 3% medium trucks and 3% heavy trucks all traveling at a speed of 65 mph. The pavement sections were assumed to be appropriate for a 50-year service that was also used as the analysis period for this case.
|
From page 18... ...
18 pavement alternative and $5,781,000 for the HMA pavement alternative. LCCA Results and Discussion Table 4 provides the results of the LCCA for the two alternatives: HMA pavement with a 7-year rehabilitation cycle and 11a: HMA pavement & ARFC overlay 11b: PCC pavement & barriers not to scale 0 7 14 21 28 35 42 49 50 Initial Construction ($5,781,000)
|
From page 19... ...
19 alternative yields the lowest present value of agency costs but the PCC alternative yields the lowest present value of user costs. It should also be considered that present values for the alternatives are functions of the assumed project life.
|
From page 20... ...
20 Figure 13. TNM-predicted traffic noise levels at 100 ft for random transversely tined PCC pavement.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.