Mei L.I.,Shanghai Geotechnical Investigations Design Institute Co.
Acta Geologica Sinica | Year: 2016
Chemical analysis of groundwater in petroliferous basins can be an effective way to determine the regional hydrogeological regime and to evaluate the preservation conditions of hydrocarbons. This paper presents the hydrochemical distribution of both individual aquifers and different structural units within the Palaeogene strata of the Gaoyou subbasin in the North Jiangsu Basin, east China. The results show that the salinity of the Palaeogene aquifers in the Gaoyou subbasin displays a systematic increase from the central deep depression to the periphery areas, and shows a reverse trend as the burial depth increases. Salinity maps of individual aquifers suggest that formation water in the deep layers at the centre of the study area probably retains original features of fresh lake water. Geofluids near the central deep depression of the Gaoyou subbasin migrate vertically through the Zhenwu and Hanliu faults, while those of the northern slope belt mainly flow laterally through aquifers. Both low and high salinity formation water can be found in the hydrocarbon producing areas. The low salinity zones commonly affected by infiltrated meteoric water are unfavourable conditions for the preservation of trapped hydrocarbons. © 2016 Geological Society of China Source
Luo C.-H.,Shanghai Geotechnical Investigations Design Institute Co. |
Wei J.-H.,Shanghai Geotechnical Investigations Design Institute Co.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2012
Through many engineering practices in Shanghai and the surrounding area, considering many aspects, such as engineering pile, retaining pile, inner support, soil reinforcement and isolation pile and so on, the methods for decreasing the initial displacement of surrounding environment of deep excavations in soft soil are summarized. It may provide a reference for similar projects. Source
Su H.,Shanghai Geotechnical Investigations Design Institute Co. |
Yang S.-F.,Shanghai Geotechnical Investigations Design Institute Co. |
Gu G.-R.,Shanghai Geotechnical Investigations Design Institute Co.
Yantu Lixue/Rock and Soil Mechanics | Year: 2015
Based on quantities of test data, a elliptic equation is set up for the elastoplastic stage of pressure meter test with the method of curve fitting; and then, the SMP yield criterion and ROWE flow rule are used to deduce the relationship matrix of the stress increment and strain increment in plastic stage. In the elastic stage, the stress and strain is supposed to obey the generalized Hooke's law; so the elastoplastic constitutive model is set up, in which the stress-strain relationship is clear; and the parameters are easy to be obtained obtain from the pressure meter test. Accordingly, the calculating program is worked out to compare the model result and the actual test curve, which can validate the model primarily. Furthermore, the model is compiled as a UMAT subroutine, which can be used for finite element analysis in ABAQUS. The comparative analysis shows that, the deformation of this model is larger than that of elastic model and smaller than that of Mohr-Coulomb model, which is consistent with the model assumptions. The elastoplastic constitutive model of soil based on pressure meter test is easy to obtain the parameters and convenient to be used in engineering. ©, 2015, Academia Sinica. All right reserved. Source