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101.
102.
Several theoretical, empirical and semi-empirical methods are available in the literature to predict settlement of drilled
shafts in sandy soils. In the Arabian Gulf countries, specifically in the United Arab Emirates, equations and procedure from
the rest of the world are being used in analysis and design of drilled shafts without proper validation. It is the aim of
this study to assess the applicability and evaluate the accuracy of two well known, and commonly used methods for pile prediction
in the United Arab Emirates (UAE), namely Vesic (1977) and Poulos (1979), via comparison with data from field pile load tests
conducted on shafts drilled in the region. Some of these tests were conducted for the purpose of this study, while others
were made available through the courtesy of International Piling Contractors who are active in the region (e.g. Bauer International
and Swiss Borings). Pile load test data were analyzed to back-calculate the model parameters related to settlement under different
loading stages. Geological data and soil properties were obtained from studies conducted at the relevant sites. An effort
is made to correlate soil properties with the prediction models. Statistical analysis is conducted to assess the accuracy
of the results obtained from the two methods at different stages of loading via those obtained from pile load tests. Moreover,
a detailed parametric study is conducted to assess the effect of the related parameters on the predicted pile settlement and
the estimated settlement at different stages of loading. The study concluded with a recommendation of the most appropriate
models and procedures to be followed for predicting the settlement of drilled shafts in the UAE, together with useful charts
and correlation relations. Results showed that settlement values predicted by Vesic (1977) and Poulos (1979) overestimates
the true values.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
103.
基于灰关联分析的GPS高程拟合加权平均函数模型权函数优选 总被引:6,自引:0,他引:6
基于灰色系统理论的灰关联分析方法,提出了权函数的优选方法,实例分析表明其具有较好的实用价值. 相似文献
104.
1. Introduction The quasi-biennial oscillation (QBO) of the mean zonal wind in the equatorial stratosphere was discov- ered by Reed et al. (1961) and Veryard and Ebdon (1961). Later, Funk and Garnham (1962) and Ra- manathan (1963) were the first to descri… 相似文献
105.
The time history of strong ground motion can be synthesized by empirical Green's function (EGF) method.Firstly a large seismic event is discretized into a series of subevents; secondly recordings of earthquakes with proper size and spatial distribution are chosen as time history (EGF) of those subevents; finally the EGFs are summated to get the time history of ground motion caused by the large event. 相似文献
106.
High buildings or architectural complex in urban areas remarkably distort the urban surface wind fields. As the air flow approaches,local strong wind may appear around the buildings. The strong wind makes the pedestrians on sidewalks, entrances and terrace very uncomfortable and causes the pedestrian level wind environment problem. In this studies, hot-wire wind measurement, wind scouring in wind tunnel and numerical computation were carried out to evaluate the wind environment of tall buildings in the prevailing flow conditions in Beijing areas. The results obtained by three techniques were compared and mutually verified. The conclusions drawn from three approaches agree with each other. Also the advantages and limitations of each method were analyzed. It is suggested that the combination of different techniques may produce better assessment of wind environment around high buildings. 相似文献
107.
108.
The influence of cavern’s span on surrounding rock classification is getting more and more recognition along with large span underground working’s increasingly coming forth. The authors analyse the timbering expense of cavern in jointed rock mass, the radius of plastic loosened zone and the size effect of macroscopical mechanical parameters of rock mass. Based on the complexion of depressing of surrounding rock’s stability due to increment of cavern’s span, the authors pinpoint attaching importance to the influence of cavern’s span on surrounding rock classification; and suggest reckoning the factor of cavern’s span in surrounding rock classification scientifically by studying the size effect of rock mass’s physico-mechanical parameters. 相似文献
109.
Bin Chen 《Geochimica et cosmochimica acta》2005,69(22):5387-5388
110.