The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loo...The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loop anchorage prestressing loss(PL) values of inner lining(IL)in Yellow River-crossing tunnel under two anchorage systems,including twice- tension anchorage system and HM(Chinese transliteration is huanmao)anchorage system,are introduced. The software ANSYS is selected to realize the three-dimensional(3D) finite element modeling to accomplish simulation and calculation works under the two anchorage systems,respectively. Stress processes of IL under the two working conditions,of which one is completed cable tensioning(CCT) and the other is water in the tunnel with the designed water pressure(DWP),are contrasted and analyzed. Impacts of prestressing forces of anchor cables on structural safety under the two anchorage systems are contrasted. The calculation results show that the twice-tension anchorage system can reduce PL effectively and then increase prestresses of wall concrete(WC). Meanwhile,the anchorage system has the advantages of improving security and stability of tunnel structure,reducing project costs and saving steel consumption. The research work is available to related design and construction of anchor cable,and is worthy of promotion and application.展开更多
To determine the appropriate soft foundation treatment for a river-crossing tunnel, freezing reinforcement design and technology were introduced based on the channel tunnel design and construction practice. Through fi...To determine the appropriate soft foundation treatment for a river-crossing tunnel, freezing reinforcement design and technology were introduced based on the channel tunnel design and construction practice. Through finite element analysis and engineering practices, two rows of horizontal perforated freezing pipes were designed and installed on both sides of a passage for tunnel rein- forcement, which produced the thickness and strength of frozen crust that satisfied the design requirements. These information are valuable for guiding the design and construction of river-crossing tunnels in coastal areas.展开更多
基金National Natural Science Foundation of China(No.51079107)Fundamental Research Funds for the Central Universities(No.5082022)
文摘The load compensation equipment for anchor cable named low retraction prestressed anchorage system with twice-tension(referred to as twice-tension anchorage system) is proposed in the paper. Calculation results of loop anchorage prestressing loss(PL) values of inner lining(IL)in Yellow River-crossing tunnel under two anchorage systems,including twice- tension anchorage system and HM(Chinese transliteration is huanmao)anchorage system,are introduced. The software ANSYS is selected to realize the three-dimensional(3D) finite element modeling to accomplish simulation and calculation works under the two anchorage systems,respectively. Stress processes of IL under the two working conditions,of which one is completed cable tensioning(CCT) and the other is water in the tunnel with the designed water pressure(DWP),are contrasted and analyzed. Impacts of prestressing forces of anchor cables on structural safety under the two anchorage systems are contrasted. The calculation results show that the twice-tension anchorage system can reduce PL effectively and then increase prestresses of wall concrete(WC). Meanwhile,the anchorage system has the advantages of improving security and stability of tunnel structure,reducing project costs and saving steel consumption. The research work is available to related design and construction of anchor cable,and is worthy of promotion and application.
文摘To determine the appropriate soft foundation treatment for a river-crossing tunnel, freezing reinforcement design and technology were introduced based on the channel tunnel design and construction practice. Through finite element analysis and engineering practices, two rows of horizontal perforated freezing pipes were designed and installed on both sides of a passage for tunnel rein- forcement, which produced the thickness and strength of frozen crust that satisfied the design requirements. These information are valuable for guiding the design and construction of river-crossing tunnels in coastal areas.
