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1.
El-Hussain I. Deif A. Al-Jabri K. Mohamed A. M. E. Al-Rawas G. Toksöz M. N. Sundararajan N. El-Hady S. Al-Hashmi S. Al-Toubi K. Al-Saifi M. Al-Habsi Z. 《Natural Hazards》2013,69(3):1919-1950
Natural Hazards - Site characterization was carried out for Muscat region using the ambient noise measurements applying the horizontal-to-vertical spectral ratio (HVSR) technique and using active... 相似文献
2.
Development of ground-shaking maps for the Sultanate of Oman 总被引：1，自引：1，他引：0
3.
Solidification of Tank Bottom Sludge 总被引：1，自引：0，他引：1
Ramzi A. Taha Yahia E.-A. Mohamedzein Amer A. Al-Rawas Yahya Al-Suleimani 《Geotechnical and Geological Engineering》2010,28(1):15-25
Tank bottom oily sludge (S) is collected from tank bottoms during cleaning operations and contaminated soil is collected after
spills and leakages. Disposal of tank sludge is a significant item of tank maintenance for producers, refiners and transporters
of petroleum materials. The objective of this paper is to investigate the use of various additives in the solidification of
tank bottom sludge. The sludge was solidified using various combinations of additives including ordinary Portland cement (OPC),
cement by-pass dust (CBPD) and quarry fines (QF). Geotechnical and leachability properties of the mixtures were determined.
The use of OPC alone as a solidifying agent yielded the best results. This was followed by blends S:OPC:QF of 1:0.5:1.5 and
S:CBPD of 1:2. Economically, the latter two mixtures would be considered more cost-effective in solidifying the sludge as
the additives are waste by-product materials. The Toxicity Characteristic Leaching Procedure (TCLP) results indicated that
no extracts exceeded the threshold TCLP limits established by U.S. Environmental Protection Agency (USEPA). The solidified
material can be used in construction of roads, embankments and landfill layers. 相似文献
4.
Yahia E.-A. Mohamedzein Amer A. Al-Rawas Mohammed Y. Al-Aghbari Ahmed Qatan Abdul-Hamid Al-Rawas 《Engineering Geology》2005,80(3-4):271-281
The possibility of using crushed shales as landfill liners is investigated in this study. Two types of shales were studied by performing the following laboratory tests: hydraulic conductivity, compaction, swelling, consolidation, X-ray diffraction (XRD), scanning electron microscope (SEM) and chemical analysis. For both compacted shales, the hydraulic conductivity was in order of 10− 7 cm/s or less which satisfies the specifications for landfill liners. The results of XRD and SEM support the low values of the hydraulic conductivity. Because of the dominant presence of low-activity kaolinite, there was no significant change in the hydraulic conductivity when the compacted shales are exposed to calcium chloride solution. The compressibility of the compacted clay was low and no serious post-construction settlement is expected. The shear strength of the compacted shales was within the usual expected range for earthen liners and, therefore, should pose no challenges with respect to shear strength. The crushed shales also satisfy the other criteria related to Atterberg limits and grain size. 相似文献
5.
Ahmed Al-Futaisi Ahmad Jamrah Amer Al-Rawas Saif Al-Hanai 《Environmental Geology》2007,51(8):1317-1327
In this paper, Shuwaymiyah palygorskite in the Sultanate of Oman has been characterized mineralogically by X-ray diffraction
(XRD) and electron microscopy, chemically by oxide compositions, structural formulae, and cation exchange capacity (CEC),
and physically by specific surface area and adsorption isotherms. Batch adsorption studies were performed to evaluate the
adsorption performance of methylene blue (MB) basic dye on the local clay mineral. The quantitative XRD analysis indicates
that the purity of some selected samples of palygorskite clay is very high (about 70% of the clay minerals are palygorskite
and 30% kaolinite). The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images clearly support
this conclusion. The adsorption equilibrium revealed that Shuwaymiyah palygorskite clay can uptake up to 51 mg of MB per 1 g
mass of clay. MB adsorption is best fitted by Langmuir isotherm, and a pseudo-second-order kinetic model can be efficiently
used to predict the kinetic of adsorption of MB by the palygorskite. The results obtained from these laboratory-scale adsorption
tests indicate the promising adsorption capability of the Omani palygorskite. 相似文献
6.
This paper aims at determining the failure probability and the corresponding most predominant failure mode at both ultimate (ULS) and serviceability (SLS) limit states of a circular foundation resting on a (c, φ) soil and subjected to an inclined loading. The failure modes at ULS are the footing sliding and the soil punching while those at SLS are the exceedance of tolerable horizontal and vertical footing displacements. The probabilistic results based on the response surface methodology have shown that at both ULS and SLS, there is a load inclination where neither mode of failure is predominant. This inclination corresponds to the loading configurations situated on the line joining the origin and the maximal point of the interaction diagram. In a second stage, the results of a sensitivity analysis showing the effect of the different statistical parameters of the uncertain variables on the value of the failure probability were presented and discussed. 相似文献
7.
Tamara Al-Bittar Abdul-Hamid Soubra 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2017,11(2):215-229
This paper presents a probabilistic analysis to compute the probability density function of the bearing capacity of a strip footing resting on a spatially varying rock mass. The rock is assumed to follow the generalised Hoek–Brown failure criterion. The uniaxial compressive strength of the intact rock (σc) was considered as a random field and the geological strength index was modelled as a random variable. The uncertainty propagation methodology employed in the analysis is the sparse polynomial chaos expansion. A global sensitivity analysis based on Sobol indices was performed. Some numerical results were presented and discussed. 相似文献
8.
Amer A. Al-Rawas 《Engineering Geology》1999,53(3-4):327-350
The factors controlling the expansive nature of the soils and rocks in Northern Oman were studied. Basic geotechnical data from over 40 sites were collected and using empirical relationships, swelling potentials were identified. A laboratory testing program was carried out using undisturbed samples from these swell pressures up to 3.5 MPa, and swell percent values up to 30 were measured. The clay minerals and cations of these samples were determined and Na-smectite was identified as being the main clay-mineral present. Microfabric studies showed generally dense clay matrices. However, these swelling materials exist as impersistent bands with non-swelling soils and rocks which makes prediction of the ground heave problematic. 相似文献
9.
Geological and engineering characteristics of expansive soils and rocks in northern Oman 总被引：3，自引：0，他引：3
The geology and former climate of northern Oman favoured the formation of smectite clay minerals in certain materials which are implicated in ground heave problems. Investigations have shown that the smectite content of these expansive materials was developed in Oligocene, Miocene and Pliocene times. No evidence of a significant content of smectite was found in pre Eocene strata or in Quaternary strata, except for Desert Fill. It is shown that the main types of expansive materials in northern Oman are bentonitic mudstones, marls and silty mudstones, argillaceous dolomitic limestone, altered conglomerates and the desert fill derived from these. These swelling materials exist as impersistent bands within the bedrock Tertiary conglomerates and limestones. A geotechnical testing program was carried out on undisturbed samples from Sultan Qaboos University staff housing areas where building damage had occurred, to evaluate mineralogical composition, cation content and swelling characteristics. The test results characterized these soils/rocks as highly expansive type with Na-smectite as the dominant clay mineral. 相似文献
10.
ABSTRACT This study explores previously unreported linkage between recession rates of rainfall hyetograph and river flow hydrograph in an arid environment in Sultanate of Oman. Ephemeral streams are hydraulically disconnected from groundwater aquifers and depend on rainfall to produce water that flows only for hours or a few days at most. It therefore prompted to hypothesize that the recession rate of the rainfall event controls the corresponding recession of river flow. To test this assumption, 1-h river flow rates and 20-min rainfall rates in Al-Khoud catchment area for the period 1997–2013 were analysed. The river flow recession rate and antecedent river flow were found to be inversely proportional, while their relation improved with increasing time span of cumulating the antecedent river flow. The results further show that the simulation of river flow recession rate can be improved by incorporating the combined effects of rainfall recession rate and antecedent moisture content. 相似文献