A Comprehensive Review on the Effectiveness of Existing Noise Barriers commonly used in the Railway Industry

Abstract

Abstract. Nowadays, advanced development and sophisticated new technology have led to various types of environmental pollution such as water, air, land, thermal pollution and so on. Recently, however, noise pollution is becoming one of the major threats to the world especially in urban areas where it adversely affects the quality of life of the public. In Malaysia, the Department of Environment has identified that the average transportation noise levels in major cities in peninsular Malaysia are 71.6 dB (A) and 70.4 dB (A) during the day and night respectively. The noise is usually emitted by airplanes, trains, vehicles, motorcycles, trucks and etc. Even though rail transport requires less energy and emits less hazardous substances, it has contributed to noise pollution issues and several health hazards among urban inhabitants such as deafness, nervous breakdowns, mental disorder, heart troubles, high blood pressure, headaches, dizziness, inefficiency and insomnia. Therefore, many studies attempt to reduce noise pollution by applying noise barriers at noise polluted areas via various approaches. This paper aims to explore the effectiveness of noise barriers using noise absorption performance due to several factors such as type of absorbent materials, material thickness, density, porosity and design. This research has found that the thicker the specimen and the denser the absorbent material, the better the sound absorption performance. Besides that, barrier design also plays a major role in determining its effectiveness, where the effectiveness of noise barriers should be high and long enough to break the line-of-sight between the sound source and the receiver. There are several methods that can be used to measure the effectiveness of noise barriers such as the Adrienne Method (in-situ measurement method) and impedance tube method (laboratory measurement method) to measure the acoustic absorption. Nevertheless, the impedance tube measurement method provides the most precise results with the least measurement uncertainty as it only required small samples of the material.

Long-Term Sustainability Approach in Road Traffic Noise Wall Design

“…The most significant of these is the surface density of the barrier [26]. A panel is considered to have sufficient insulating properties if its surface density is 20 kg/m 2 or higher [49].…”

Business Architecture Model in Strategic Information System Management for Effective Railway Supply Chain Perspective

“…RI plays assumes a significant job and turns into an impetus for financial development in Malaysia with the commitment of 35% of the country's Gross Domestic Product (GDP) while shares 58% of absolute work [28]. In Malaysia, RI can be grouped into four (4) categories, namely: (1) Electric Train Service (ETS), (2) Monorail, (3) Express Rail Link (ERL), and (4) Light Rapid Transit (LRT) [29]. The four main sectors are heavy rail service sectors [30].…”

The durability of concrete containing recycled tyres as a partial replacement of fine aggregate

“…In order to prevent environmental problems from worsening, recycling tyres is an innovative idea or way in this case [12][13][14][15][16]. Recycling tyres is the processes of recycling vehicle tyres that are no longer suitable for use on vehicles due to wear or irreparable damage (such as punctures) [17].…”