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361.
Liu Jianxin Zhang Conghui Pang Xishun 《应用地球物理》2006,3(1):62-67
The Formation Evaluation Tool (FET) introduced in the paper represents a new generation of formation evaluation systems developed and manufactured by China Oilfield Services Limited (COSL), CNOOC, using a FET technology transfer from Crocker Research, Australia. The system has been applied successfully in the Bohai Sea and South China Sea. For instance, a multilayered oil and water system has been confirmed with the aid of accurate formation pressure tests, even in very thin beds and edge water reservoirs, overcoming the difficulty of determining this kind of oil-water and gas-water contacts. Moreover, the FET pumping and real-time fluid monitoring function allows acquiring a true sample of formation fluid unpolluted by drilling mud which plays an important role in determining the fluid properties of the target stratum and analyzing the fluid component. The principles and purpose of the Formation Evaluation Tool (FET) will be briefly introduced and successful examples of the application of the technology will be described in detail in this paper. 相似文献
362.
Xiu Luo Hiroshi Haya Tomoaki Inaba Tomoki Shiotani 《Soil Dynamics and Earthquake Engineering》2006,26(12):1101-1110
One difficult task for the seismic diagnosis of existing structures is how to nondestructively evaluate the damage degree of invisible substructures, such as embedded foundations. To diagnose substructures efficiently, a method for nondestructive inspection is developed by applying acoustic emission (AE) technique. As a newly proposed method, characteristics of secondary AE induced by train operations were investigated, and experiments using model piles and in-situ AE monitoring of in-service railway bridges conducted under railroad traffic, from which it was demonstrated that the proposed method is practicable enough to detect invisible defects in structures. A new index, known as RTRI (ratio of Repeated Train load at the onset of AE activity to Relative maximum load for Inspection period) is proposed for structural damage qualification based on the results of in-situ AE monitoring. 相似文献
363.
When individual cells of a multiple-cell treatment wetland are hydraulically connected, the wetland has a cell-network structure. The hydraulic performance of treatment wetlands is often characterized using tracer residence time distributions (RTDs) measured between the wetland inlet and outlet, such that the wetland is considered as a single hydraulic unit, regardless of the extent of networking between individual internal cells. This work extends the single hydraulic unit approach to enable the specification of moments and RTD parameters for individual cells, or clusters of cells, within the cell-network based on inert tracer tests with injection only at the network inlet. Hydraulic performance is quantified in terms of hydraulic efficiency and travel time dimensionless variance using both the method of moments and RTD modeling. Cell-network analysis was applied to a case study from the Orlando Easterly Wetland (OEW), demonstrating the improvement in hydraulic performance of individual wetland cells following wetland restoration activities. Furthermore, cell-network analysis indicated that the location of water quality sampling station locations within the cell network can significantly affect the accuracy of pollutant removal effectiveness estimation when the individual sample station RTD does not represent the hydraulic unit RTD. At the OEW, it was determined that historical nutrient removal effectiveness estimation may be underestimated for one area and overestimated for another, and recommendations were provided for sample station locations to minimize future performance estimation errors. 相似文献
364.
Stefan Becker Marco Gemmer Tong Jiang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,20(6):435-444
Precipitation trends in the Yangtze River catchment (PR China) have been analyzed for the past 50 years by applying the Mann-Kendall trend test and geospatial analyses. Monthly precipitation trends of 36 stations have been calculated. Significant positive trends at many stations can be observed for the summer months, which naturally show precipitation maxima. They were preceded and/or followed by negative trends. This observation points towards a concentration of summer precipitation within a shorter period of time. The analysis of a second data set on a gridded basis with 0.5° resolution reveals trends with distinct spatial patterns. The combination of classic trend tests and spatially interpolated precipitation data sets allows the spatiotemporal visualization of detected trends. Months with positive trends emphasize the aggravation of severe situation in a region, which is particularly prone to flood disasters during summer. Reasons for the observed trends were found in variations in the meridional wind pattern at the 850 hPa level, which account for an increased transport of warm moist air to the Yangtze River catchment during the summer months. 相似文献
365.
通过对上海轨道交通9号线宜山路车站深基坑降水试验结果分析,得到不同土层受降水影响的岩土工程特征,并对个别土层的实测沉降与由室内试验参数进行估算的沉降进行比较,以获得真实的沉降影响状况,指导深基坑的设计和施工。 相似文献
366.
367.
采用标准试验方法求得筑坝用煤矸石的最大干密度和相应的最优含水量。试验结果表明,击实作用使煤矸石的粗大颗粒发生破碎,导致其粒度组成改变,颗粒级配进一步趋于良好,有利于碾压密实。当粗粒质量分数大于60%时,煤矸石的破碎程度明显提高。当粗粒质量分数小于40%时,煤矸石的工程特性主要由细颗粒的性质决定。煤矸石的渗透系数和孔隙比之间存在指数关系。随细颗粒含量的增加,煤矸石的渗透性将显著降低。 相似文献
368.
369.
天津市堆山造景工程地基稳定监测与防治 总被引:1,自引:0,他引:1
堆山造景工程是一项利用建筑渣土,在坑塘上进行堆载的市政工程。通过对堆山造景工程的工程地质条件分析,结合工程设计、施工工期等条件,提出了清理淤泥、设置反压平台、排水、控制堆填速率等促进地基稳定的防治措施。利用孔隙水压力监测、侧向位移监测及分层沉降监测等原位监测数据,以复合型法进行反演力学计算参数,并将反演结果用于该工程地基稳定性的模拟,以指导后期工程以及类似工程的建设。 相似文献
370.
土体中大量降排水的过程实际上是土体中有效应力增长的过程。通过对抽水试验中土体渗透系数的回归分析,建立了渗透系数与有效应力增量之间的耦合响应模型关系,说明降排水过程中土体渗透系数是呈非线性变化的。 相似文献