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101.
本文通过对垂直井筒内固液两相流运动规律和摩阻损失研究,建立井筒物理模型,找出砂柱高度和产量之间的对应关系。经油田现场数据验证表明,预测方法简单,计算结果较准确,为油田高效生产提供了参考。 相似文献
102.
A. A. Adepelumi M.O. Olorunfemi 《Bulletin of Engineering Geology and the Environment》2000,58(2):125-132
It was hoped to develop an area of reclaimed land on the Lekki Peninsula of Lagos State. An investigation was therefore carried
out in order to establish the subsurface geological/geo-electrical sequence; to identify the sand columns and determine their
thickness and prepare a map of the geomorphological features of the original, pre-fill terrain. Vertical electrical resistivity
soundings (VES) and penetrometer tests were carried out in a sand filled segment of the Lekki Peninsula. The information obtained
showed a good correlation between the geomorphological features as interpreted from the aerial photographs and those identified
from maps derived from the VES/penetrometer results.
Received: 28 August 1998 · Accepted: 18 January 1999 相似文献
103.
Lubo Liu Christine M. Rust Joseph R. V. Flora C. Marjorie Aelion 《Canadian Metallurgical Quarterly》2002,128(12):1128-1138
A one-dimensional mathematical model was developed to simulate pH control using an encapsulated phosphate buffer during denitrification in a sand column. The parameters required for the model were obtained from direct physical measurement, from a tracer study to characterize the dispersion coefficient in the column, and from batch experiments designed to obtain an empirical expression describing the variation of the first-order rate constant for the encapsulated buffer core release with pH. First-order kinetic constants describing the rates of denitrification and ethanol biodegradation were obtained by fitting the model to column runs without the encapsulated buffer. With these parameters, the model was subsequently used to predict the performance of column runs containing the encapsulated buffer. Since denitrification was essentially complete in the sand columns, an increase in the effluent pH was observed. This pH increase was counteracted by the controlled release of the acidic core of the encapsulated buffers added in the columns. The model reasonably predicted the release of the encapsulated buffer core and the performance of the encapsulated buffer for controlling pH in the column. 相似文献
104.
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106.
Performing deep excavations in karst regions is likely lead to geo-hazards, e.g. sinkholes, water ingress, and ground surface settlement. This case report presents the performance of a 16-m deep excavation in sand covered karst in Metro Line no. 9, Guangzhou, China. The performances during deep excavation, including lateral wall deflection, vertical wall movement, ground surface settlement, and settlement of adjoining buildings, were monitored and evaluated. Based upon the interpretation of the field measurements, the following major findings were obtained: (i) the lateral wall deflection and surface settlement measurements were smaller those cited in other case studies with similar geological conditions, (ii) both the grouting of the karst cavern and the use of the socket diaphragm wall panel dominated the performance of the deep excavation; (iii) the type of the founding structure could significantly affect the settlement development of the adjoining buildings. This case report provides insight into the design and construction of deep, narrow excavations in sand covered karst in a metropolitan environment. 相似文献
107.
In recent years, X-ray CT scanners with task-specific modifications, such as microfocus and/or a synchrotron, have been widely implemented in a variety of fields, including medical and industrial fields. Since microfocus X-ray CT systems enable the visualization of whole samples, and also yield a relatively high resolution of the region of interest in the sample, they are commonly utilized in the fields of soil mechanics and geotechnical engineering. This paper describes a novel loading test apparatus that is specifically designed for microfocus X-ray CT systems capable of performing loading tests to investigate soil behavior during the installation of driven open-section piles. The loading tests were designed to take the micro-level spatial resolution of microfocus X-ray CT systems into account. Digital image correlation (DIC) is subsequently implemented to analyze the obtained CT images, making it possible for measurements to be taken of the displacement fields in the ground following installation of the model pile. Finally, the versatility of this novel test apparatus is proof of its high potential for application in different types of loading tests. 相似文献
108.
109.
《Soils and Foundations》2022,62(5):101205
Global sustainable development faces challenges in greenhouse gas emission, consumption of non-renewable resource and energy, waste landfilling, and environmental pollution. Geotechnical engineering also faces similar challenges; for example, the use of cement and lime for stabilisation/solidification (S/S) of contaminated soil is associated with carbon dioxide (CO2) emission and consumption of limestone and energy. In this context, this study introduces a sustainable S/S method by using an industrial waste, ladle furnace slag (LFS), and a greenhouse gas, CO2, to replace common additives for S/S of lead (Pb)-contaminated soil. LFS was first mixed with Pb-contaminated soils and then CO2 was introduced into the soil for carbonation. The results showed that LFS-stabilised Pb-contaminated soils could achieve CO2 uptake up to 18% of LFS mass. After carbonation, the concentration of leached Pb from contaminated soils was reduced by three orders of magnitude than that without carbonation, demonstrating higher S/S efficacy than cement, lime, and magnesia. Additionally, this method can improve soil strength, as well as reduce non-renewable resource consumption, energy use, LFS landfilling, and additive cost. 相似文献
110.
《Soils and Foundations》2022,62(5):101218
This paper presents a study of liquefaction analysis at sand layers of the Izumio site, under ground motion variation during a strong earthquake in Osaka, Japan. Site investigation using standard penetration test and shear wave velocity measurement is conducted. Finite element liquefaction site response analysis integrated with a strain space multiple mechanism model is conducted. Ground motions variation is considered based on the seismic record at surrounding seismic stations. Attenuation analysis is conducted to determine the scaling factor for ground motions. Several results, such as acceleration profiles and cyclic behaviours are presented. The empirical analysis is also conducted to verify the results of the numerical analysis. The results explained that cyclic behaviours of sandy layers in the Izumio site show the liquefaction tendency. The results also showed that sandy layers are indicated as critical layers during the strong earthquake due to the excess pore water pressure reaching the liquefaction threshold. The results of the empirical analysis also present liquefaction indication at sand layers under the variation of ground motion, since the factor of safety against liquefaction is less than 1. The results are generally well-agree with liquefaction evidence and prediction presented in the previous study. The results could bring practical importance in understanding liquefaction potential in the study area. 相似文献