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The public’s awareness of noise and vibration forms a significant barrier to further development of railways. This chapter begins with a short introduction to the main fundamental aspects of acoustics, including decibels, frequency analysis, the propagation of sound with distance and common measurement quantities. The main sources of railway noise are discussed, including rolling noise, impact noise, curve squeal and aerodynamic noise. Simple calculation procedures are described that can be used to assess the impact of railway noise and to compare it with legal limits. The final section is devoted to ground vibration, which is a related form of environmental disturbance.

The correlations between mechanical behaviour, tensile strength, and rock parameters of metasedimentary rock samples in Karak, Pahang’s New Austrian Tunnelling Method (NATM) were statistically evaluated from the rock mechanic laboratory works at the selected sections around 2,000 m of the tunnel (named as NATM-1). According to a statistical analysis, lithotypes, geological structures, and region geology have a significant impact on the mechanical behaviour of the metasedimentary rock. In the Brazilian test, the fracture behaviour of the disc specimens was highly related to the reliability and precision of the experimental data by validations of methods. In this work, the impact of different loading methods and rock lithotypes on the failure mechanism of Brazilian discs was examined utilising five different metasedimentary rock types and three different loading methods. During the loading operation, the strain and displacement fields of the specimens were recorded and evaluated using a computerised strain gauge system. The rock types, according to experimental data, have a significant impact on the peak load and deformation properties of Brazilian discs. With the method below, tensile strength point of a disc specimen is clearly regulated by the material stiffness and tensile–compression ratio. Seismic occurrences have had a substantial impact on changing the rock and exerting forces that may affect its mechanical characteristics as well as its vulnerability to weathering effects or discontinuities. As a result, the goal of this study is to look into the connection between rock mechanics and metasedimentary rock stress analysis in NATM-1, Karak, Pahang.

Earthworks are the embankments and cuttings that allow a railway to maintain a certain line, level and grade through the landscape. Earth embankments consist of an engineered bank of earth that carries the railway above the natural ground. A cutting is used to carry the railway through ground with a natural level above the line of the railway. Modern (post 1960s) earthworks are carefully engineered to perform well. However, many railways run on earthworks that were constructed over 100 years ago without the use of mechanised plant. The quality of construction of older earthworks was often poor compared with present-day engineering practice. Ageing of the earthwork structures, and the greater demands of heavier and faster trains and climatic change, means that earthworks suffer ultimate and serviceability failures that can present operational difficulties. Older earthworks that fail or do not perform well require maintenance and repair, and sometimes complete replacement. This chapter explores the main engineering considerations for modern earthworks, and the challenges associated with older earthworks including their modes of failure and upgrade and repair.

This chapter investigates the role of macro corporate governance (legal and extra legal institutions) in determining the extent of ultimate excess control (i.e., the ownership-controls rights divergence of the ultimate owner) using a large sample of Asian and European companies. We find that the level of excess control is lower in countries with (1) good investor protection and better enforcement of information disclosure and (2) fairer competition laws, higher newspaper diffusion, and more regulated insider trading. Controlling for institutions subsumes the effect of firm-level determinants, as only leverage appears to be negatively and significantly related to excess control.

Despite the fact that recent anthropological interest in infrastructure has done much to illuminate the infrastructure asset as an assemblage of actors, technologies and ideas, an interdisciplinary approach is required to unpack how the infrastructure project comes together as an assemblage and to define the role that financial technologies and discourses play in shaping it. Here, an interdisciplinary approach is applied to a novel infrastructure asset, London's Thames Tideway Tunnel, in order to show how multiple actors and visions of the world are brought together to make the infrastructure asset come to fruition. The paper concludes that this interdisciplinary approach to infrastructure can allow us to keep multiple sides of the infrastructure project in sight simultaneously. This includes both the creation of a rhetorical vision and spectacle around the asset, and the underlying financial arrangements that bind it together. If we do so, we can understand how new infrastructural forms utilise particular financial technologies and ideas to change the relationship between the public and the private, and between consumers and providers, and act towards the creation of a new ‘public good’ that normalises private provision.