This paper is concerned with the stability analysis of reinforced slopes.A new approach based on the limit equilibrium principle is proposed to evaluate the stability of the reinforced slopes.The effect of reinforceme...This paper is concerned with the stability analysis of reinforced slopes.A new approach based on the limit equilibrium principle is proposed to evaluate the stability of the reinforced slopes.The effect of reinforcement is modeled as an equivalent restoring force acting the bottom of the slice and added into the general limit equilibrium(GLE) method.The equations of force and moment equilibrium of the slice are derived and corresponding iterative solution methods are provided.The new method can satisfy both the force and the moment equilibrium and be applicable to the critical failure surface of arbitrary form.Furthermore,the results predicted by the proposed method are compared with the calculation examples of other researchers and the centrifuge model test results to validate its correctness and effectiveness.展开更多
The thermal history and organic matter maturity evolution of the source rocks of boreholes in the Puguang gas field were reconstructed. An integrated approach based on vitrinite reflectance and apatite fission track d...The thermal history and organic matter maturity evolution of the source rocks of boreholes in the Puguang gas field were reconstructed. An integrated approach based on vitrinite reflectance and apatite fission track data was used in the reconstruction. Accordingly, the geothermal conditions of gas accumulation were discussed in terms of the geological features of reservoirs in the northeastern Sichuan Basin. The strata reached their maximum burial depth in the Late Cretaceous era and were then uplifted and denuded continuously to the present day. The geothermal gradient and heat flow in the Late Cretaceous era were approximately 30.0 °C/km and 66 mW/m2, respectively, which were both higher than those at present. The tectonothermal evolution from the Late Cretaceous era to the present is characterized by denudation and cooling processes with an erosion thickness of2.7 km. In addition to the Triassic era, the Jurassic era represents an important hydrocarbon generation period for both Silurian and Permian source rocks, and the organic matter maturity of these source rocks entered into a dry gas period after oil generation. The thermal conditions are advantageous to the accumulation of conventional and unconventional gas because the hydrocarbon generation process of the source rocks occurs after the formation of an effective reservoir cap. In particular, the high geothermal gradient and increasing temperature before the denudation in the Late Cretaceous era facilitated the generation of hydrocarbons, and the subsequent cooling process favored its storage.展开更多
基金funded by the Key Industrial Science and Technology Project of Shaanxi Province(No.2015GY149)the Scientific Project funded by the Ministry of Housing and Urban-Rural Development of the People’s Republic of China Council(No.2015-K2-008)
文摘This paper is concerned with the stability analysis of reinforced slopes.A new approach based on the limit equilibrium principle is proposed to evaluate the stability of the reinforced slopes.The effect of reinforcement is modeled as an equivalent restoring force acting the bottom of the slice and added into the general limit equilibrium(GLE) method.The equations of force and moment equilibrium of the slice are derived and corresponding iterative solution methods are provided.The new method can satisfy both the force and the moment equilibrium and be applicable to the critical failure surface of arbitrary form.Furthermore,the results predicted by the proposed method are compared with the calculation examples of other researchers and the centrifuge model test results to validate its correctness and effectiveness.
基金supported by the National Key Basic Research Development Plan of China(No.2012CB214703)the National Natural Science Foundation of China(No.41102152)+1 种基金the Petro China Innovation Foundation(No.2013D-5006-0102)the Science Foundation of China University of Petroleum,Beijing(No.YJRC2013-002)
文摘The thermal history and organic matter maturity evolution of the source rocks of boreholes in the Puguang gas field were reconstructed. An integrated approach based on vitrinite reflectance and apatite fission track data was used in the reconstruction. Accordingly, the geothermal conditions of gas accumulation were discussed in terms of the geological features of reservoirs in the northeastern Sichuan Basin. The strata reached their maximum burial depth in the Late Cretaceous era and were then uplifted and denuded continuously to the present day. The geothermal gradient and heat flow in the Late Cretaceous era were approximately 30.0 °C/km and 66 mW/m2, respectively, which were both higher than those at present. The tectonothermal evolution from the Late Cretaceous era to the present is characterized by denudation and cooling processes with an erosion thickness of2.7 km. In addition to the Triassic era, the Jurassic era represents an important hydrocarbon generation period for both Silurian and Permian source rocks, and the organic matter maturity of these source rocks entered into a dry gas period after oil generation. The thermal conditions are advantageous to the accumulation of conventional and unconventional gas because the hydrocarbon generation process of the source rocks occurs after the formation of an effective reservoir cap. In particular, the high geothermal gradient and increasing temperature before the denudation in the Late Cretaceous era facilitated the generation of hydrocarbons, and the subsequent cooling process favored its storage.
