7 research outputs found
Stabilization Mechanisms of Oil Palm Empty Fruit Bunch (OPEFB) Fibre Reinforced Silty Sand [TA1-2040].
Pelbagai jenis kaedah pengukuhan telah digunapakai dalam meningkatkan kekuatan tanah. Ini menyebabkan semakin banyak kajian dilakukan dalam mengenalpasti sumber baru yang lebih sesuai sebagai alat pengukuhan.
A wide range of reinforcements have been used to improve soil performance to increase the soil strength. This has caused increased interest in identifying new accessible resources for reinforcement
Extension Of Numerical Manifold Method For Plasticity And Fracture Modelling Of Rock Mass
Previous studies on numerical modelling of geotechnical engineering problems indicate the importance of modelling in safe and sustainable designing of geotechnical projects. Generally, the stability of built engineering structures in rock is directly influenced by stability of the rock mass that contains the structure. In addition, the economical engineering design usually suggests the usage of existing rock to support the underground structure hence minimizing the additional handling of support systems. Therefore, an accurate and precise assessment of rock stability is required, that can be hugely achieved by modelling the rock mass stability. However, many approximations considered in the traditional modelling techniques of the rock mass were not able to simulate both discontinuity and continuum problems. Hence, new models have been developed and improved for providing accurate modelling techniques for rock mechanics. The Numerical Manifold Method (NMM) developed by Shi (1997) is one of the hybrid continuum–discontinuum models which is suitable for modelling complex problems in rock mechanics. However, the NMM method requires extension for solving the plasticity and cracking problems to model rock mass stability and determines reliable simulation results
Wet deposition of hydrocarbons in the city of Tehran-Iran
Air pollution in the city of Tehran has been a major problem for the past three decades. The direct effects of hydrocarbon contaminants in the air are particularly important such as their carcinogenic, mutagenic, and teratogenic effects which can be transported to other environments via dry and wet deposition. In the present study, rainwater samples were collected and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, ethyl benzene, and xylene (BTEX) as well as fuel fingerprints in two ranges of gasoline (C5–C11) and diesel fuel (C12–C20) using a gas chromatograph equipped with a flame ionization detector (GC/FID). Mean concentrations of ∑16 PAHs varied between 372 and 527 µg/L and for BTEX was between 87 and 188 µg/L with maximum of 36 µg/L for toluene. Both gasoline range hydrocarbons (GRH) and diesel range hydrocarbons (DRH) were also present in the collected rainwater at concentrations of 190 and 950 µg/L, respectively. Hydrocarbon transports from air to soil were determined in this wet deposition. Average hydrocarbon transportation for ∑PAHs, BTEX, GRH, and DRH was 2,747, 627, 1,152, and 5,733 µg/m2, respectively