The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossil...The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossils in the Upper Yunshan Formation of the Longzhaogou Group and the Lower Chengzihe For-mation of the Jixi Group, and the Qihulin Formation of the Longzhaogou Group yields Early Cretaceousbivalve and ammonite fossils. Consequently, the geological ages of the two groups are mainly, or even all, Ear-ly Cretaceous.展开更多
EPB TBMs(Earth pressure balance Tunneling Boring Machines) are extensively used in tunneling constructions because of its high efficiency and low disturbance on structures above ground. It is critically significant to...EPB TBMs(Earth pressure balance Tunneling Boring Machines) are extensively used in tunneling constructions because of its high efficiency and low disturbance on structures above ground. It is critically significant to predict the thrust acting on TBMs under different geological conditions for both the design of power system and the control of tunneling process. The interaction between the cutterhead and the ground is the core of excavation, through which geological conditions determine the thrust re-quirement combined with operating status and structural characteristics. This paper conducted a mechanical decoupling analysis to obtain a basic expression of the cutterhead-ground interactive stress. Then more engineering factors(such as cutterhead topological structure, underground overburden, thrusts on other parts, etc.) were further considered to establish a predicting model for the total thrust acting on a machine during tunneling. Combined with three subway projects under different geological conditions in China, the model was verified and used to analyze how geological, operating and structural parameters influence the acting thrust.展开更多
基金Director Foundation of Nanjing Institute of Geology and Palaeontology,Academin Sinica.
文摘The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossils in the Upper Yunshan Formation of the Longzhaogou Group and the Lower Chengzihe For-mation of the Jixi Group, and the Qihulin Formation of the Longzhaogou Group yields Early Cretaceousbivalve and ammonite fossils. Consequently, the geological ages of the two groups are mainly, or even all, Ear-ly Cretaceous.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11127202 & 11302146)
文摘EPB TBMs(Earth pressure balance Tunneling Boring Machines) are extensively used in tunneling constructions because of its high efficiency and low disturbance on structures above ground. It is critically significant to predict the thrust acting on TBMs under different geological conditions for both the design of power system and the control of tunneling process. The interaction between the cutterhead and the ground is the core of excavation, through which geological conditions determine the thrust re-quirement combined with operating status and structural characteristics. This paper conducted a mechanical decoupling analysis to obtain a basic expression of the cutterhead-ground interactive stress. Then more engineering factors(such as cutterhead topological structure, underground overburden, thrusts on other parts, etc.) were further considered to establish a predicting model for the total thrust acting on a machine during tunneling. Combined with three subway projects under different geological conditions in China, the model was verified and used to analyze how geological, operating and structural parameters influence the acting thrust.
