This review attempts to identify the health hazards, risks and causes of poor safety practices in construction sites. In addition, the differences in safety practices in both developed and developing countries and methods to improve construction site safety are discussed. Effects of some health hazards are chronic while some are acute. Mostly reported acute health hazards are "workers fall from height" and "electric shocks", while mostly reported chronic health hazard is "exposure to hazardous substances". Lack of awareness about site safety and dislike to wear Personal Protective Equipment (PPE) were identified as main causes of poor safety practices in construction sites. One of the major needs with regard to the construction industry is to enhance professionals' interests in active safety management and implementation of awareness programs, which must be developed and implemented among construction workers. Awareness on possible risk factors and knowledge on how to reduce these risk factors among workers and contractors will enhance site safety.

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The vibration generated by construction activities is transferred through soil media to the surroundings and has influence on the surrounding structures. However, the response of the structures may depend on the amount of energy received by them. The objective of this study is to investigate the characteristics of ground vibration induced by soil roller compaction and the effectiveness of waste material in reducing the propagation of the ground vibration. Several construction sites where soil compaction has been done by rollers were selected for this study. A site with a stone crushing machine which induces ground vibration similar to roller compaction (i.e., frequency and magnitude) was selected for the investigation of the effectiveness of waste material in reducing the propagation of ground vibration. A trench was introduced in the path of vibration wave propagation. The ground vibration was measured by using a four channel seismograph in the open trench and for the trench filled with locally available waste material such as rice husk and bottom ash. When operating a soil roller compactor, ground vibration in the horizontal directions (i.e., transverse and longitudinal directions)are greater than those in the vertical direction. Rice husk, compacted rice husk and bottom ash contributed to the reduction of ground vibration by 38%, 42% and 49% respectively in the transverse direction and by 14 %, 22 %, and 47 %, respectively in the longitudinal direction indicating that rice husk and bottom ash can be effectively used as in-filled damping layers.

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Ground vibration induced by pile driving has become a major concern in the construction industry, mainly due to its negative impact on the structural health of surrounding structures. Therefore, it is necessary to estimate the level of vibration propagating to surroundings before processing the pile driving to avoid any adverse impact. Pile driving is usually done in different types of soils. However, experimental evaluation of ground vibration propagation and attenuation through different soil types is not feasible, both technically and economically. The objective of the current study is to investigate the ground vibration propagation and attenuation through different types of soil by using a numerical model, which is validated with experimental measurements.A two-dimensional axisymmetric Finite Element Model (FEM) was developed by using Abaqus/CAE software. The boundary condition of the model was addressed by illustrating the application of nonreflecting boundary and fixed boundary. To minimize excessive mesh distortion during pile penetration into the soil, Arbitrary Lagrangian-Eulerian (ALE) adaptive mesh was used. The model was validated by comparing Peak Particle Velocities (PPVs) obtained from a full-scale field experiment for peat soil and laterite soil. The validated model was used to predict the ground vibration propagation and attenuation through different soil types: loess, silt, and sandy clay. A rate of vibration attenuation over a distance of 9 m was found to be 1.14 mms -1 /m, 0.66 mms -1 /m, 0.572 mms -1 /m, 0.5 mms -1 /m, and 0.41 mms -1 /m for laterite, loess, sandy clay, silt, and peat, respectively, indicating that among these five different soil types, the highest ground vibration attenuation was revealed by laterite soil while the least ground vibration attenuation was revealed by peat soil.