China 
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Managing Uncertainty in Noise Assessment Processes
Published in Robert Peters, Uncertainty in Acoustics, 2020
Colin Cobbing, Charlotte Clark
There are a number of standards and guidance that deal with the assessment of noise and vibration. These include: The Design Manual for Roads and Bridges (DMRB) [7,8];The IEMA Guidelines for Environmental Noise Impact Assessment [9];The ANC guidelines (second edition): Measurement and Assessment of Groundborne Noise and Vibration [10];British Standard (BS) 4142: 2014[11];Planning Practice Guidance: Minerals (PPG-M) [12];Planning Practice Guidance: Noise (PPG-N) [13];BS 6472: 2008 [14];ISO 14837–1: 2005 [15]; andBS 5228–1: 2009+A1: 2014: Code of Practice for Noise and Vibration Control on Construction and Open Sites [16].These guidance documents and standards are often used in noise assessments. We will refer to them in this chapter where they assist with particular aspects of managing uncertainty. However, for now, it is worth noting that some of the guidance and standards specifically require uncertainty to be addressed. For example, the BS 4142: 2014 contains a section on the steps to be taken to reduce uncertainty in the use of measurements and calculations.
Quantifying long-term rates of texture change on road networks
Published in International Journal of Pavement Engineering, 2022
Vikki Edmondson, Owen Ardill, James Martin, Michael Lim, Malal Kane, John Woodward
Road surface texture is essential for the safe and effective operation of road networks (Meegoda and Gao 2015). Texture influences noise and vehicle rolling resistance and by that fuel consumption and carbon monoxide emissions (Ejsmont et al. 2017, Hong et al. 2018). Texture also contributes to wear, with texture measurements taken from road networks helping to inform when maintenance is required (Meegoda and Gao 2015). The texture components of a highway surface have been characterised at four increasing wavelength scales: megatexture and unevenness, macrotexture and microtexture (International Organization for Standardisation 2009). Megatexture relates to wavelengths between 63 and 500 mm and amplitudes of between 0.1 and 50 mm, unevenness is characterised by wavelengths between 0.63 and 50 m. Highway pavement megatexture and unevenness is known to impact ride quality and driver comfort (Loprencipe 2019). Microtexture and macrotexture influence skid resistance and the friction available at the interface between the tyre and the road (Moore 1975, Klüppel and Heinrich 2001, Persson 2001). Macrotexture represents the texture with wavelengths between 0.5 and 50 mm and amplitudes of between 0.1 and 20 mm (formed by the shape, size and gradation of road aggregates on a pavement surface). Microtexture represents the asperities on the surface of road aggregates and has wavelengths up to 0.5 mm and amplitudes in the range of between 0.001 and 0.05 mm. Skid resistance on a pavement surface is essential for vehicle safety and is also affected by temperature, presence of contaminants, speed and tyre tread thickness (Kane and Edmondson 2018). The preservation of adequate pavement texture is achieved by a regime of monitoring and maintenance undertaken by road agencies; national practices vary, but data are typically collected at least annually (Design Manual for Roads and Bridges 2008, European Collaborative Project 2014). Generally, at road network scale unevenness, megatexture and macrotexture are monitored at traffic speed, using laser profile sensor techniques and video cameras mounted on specialist survey vehicles (Meegoda and Gao 2015). Microtexture which influences skid resistance at low speeds (Cunto and Branco 2016) and requires contact between a tyre tread and the surface asperities of road aggregates, is monitored using contact techniques. At the road network scale these contact techniques frequently used a fixed or braking test wheel, which measures the frictional contact at traffic speed made with the wheel and a wetted highway pavement. Kogbara et al. (2016) provide a full summary of contact devices and their operating principles.