This article presents a comparative study of the behaviour of clayey soil reinforcements using stone column ground improvement by means of numerical analyses. Two-dimensional finite element analyses with commercially available software, PLAXIS, were performed on end-bearing stone columns using 15-noded triangular elements to investigate the impact of the modelling type on the stress concentration ratio and failure mechanism of an improved foundation system. Consolidation analyses were conducted throughout the study using Mohr-Coulomb’s criterion. The computed values of the stress concentration ratios were compared for different key parameters, including the diameters of stone columns, c/c spacing of columns, friction angle of stone column material, and undrained cohesion of soft soil. The major conclusions of this study were that the stone column in the unit cell model shared between 2.5 to 3.14 times more loads than the surrounding soil, whilst in the plane strain model it shared between 1.7 to 2.9 times more loads. The use of plane strain approach to model the stone column gave a more comprehensive representation of the stress distribution and load transfer between the soil and columns, in addition to being a better method than the unit cell concept to evaluate the failure mode in this system.

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The assessment of soil erosion risk has been widely studied, and various methods have been established. However, most of the methods require extensive field and laboratory works that are time-consuming. The previous literature mainly focused on utilizing the existed empirical models like USLE and its derivatives. The establishment of empirical correlation can increase the efficiency to estimate the potential of soil erosion in a shorter time. This study was performed to develop an empirical correlation between the number of blows per unit penetration (M-value) obtained from Mackintosh Probe test and ROM-scale number from soil particle size distribution analysis. Both tests were conducted at three different points at one of Sg. Langat tributary riverbank nearby Universiti Kebangsaan Malaysia, Bangi. The soil at each location was analyzed at three different layers, from 0 m to 1.5 m with intervals of 0.3 m and 0.5 m for Mackintosh Probe test and ROM-scale, respectively. The result indicates that ROM-scale umber is inversely proportional to M-value with a coefficient of determination of 0.5885.

The work presented in this paper includes a field investigation of road traffic noise between residential and construction areas in a selected urban area. The aim of this study was to assess the level of noise pollution from road traffic noise in Seri Kembangan, Selangor. Therefore, this study included measurements of traffic noise level, evaluation of the percentage traffic volume between residential and construction areas; and identification of the correlation between traffic volume and traffic noise level. An EXTECH 407764 sound level meter was used to take noise level measurements for 1 hour and 30 minutes in one-minute intervals at both study sites. The parameter collected in the noise level monitoring was average noise level (LAeq). The traffic volume study was conducted using manual counts for 30 minutes. Four types of vehicles were counted, namely cars, vans, motorcycles, and heavy vehicles. Based on statistical analysis, it can be concluded that both sites had high traffic noise levels which exceeded the maximum permissible limit of 60 dBA during daytime, according to Malaysian guidelines, due to several factors. The findings show that road infrastructure such as noise barriers need to be further implemented, especially in residential areas. Mitigation of noise pollution must be further carried out by contractors. Additionally, further investigations need to be conducted by the relevant authorities to reduce the level of noise which may affect the quality of life for the communities in the area.