Abstract:
A method for selecting parameters for tunnel support based on engineering-oriented behavior discrimination of surrounding rock includes: obtaining basic geological data of a running tunnel, establishing a model of a relative location relationship between the running tunnel and a stratum, and determining a chamber environment classification of a surrounding rock of the running tunnel; determining rock integrity of the surrounding rock of the running tunnel based on the basic geological data; determining a groundwater development level of the surrounding rock of the running tunnel based on the basic geological data; determining, based on the basic geological data, whether there is a slip surface on the surrounding rock of the running tunnel; and selecting support parameters for a corresponding support measure based on behavior of the surrounding rock including the chamber environment classification, the rock integrity, the groundwater development level, and whether the slip surface exists.
Abstract:
A method for constructing a large-span station by two-wing open type semi-covered excavation and semi-reverse construction, is divided into three stages of excavation. First, excavate a first-stage inner small foundation pit, then excavate a second-stage annular foundation pit within the first-stage retaining piles and outside the range of the first-stage inner small foundation pit, and finally excavate a third-stage semi-covered excavation foundation pit below the first-stage inner small foundation pit and the second-stage annular foundation pit. By setting graded retaining piles, middle upright post piles, middle top plates, local waist beams and local concrete supports in the soil-rock combination strata, so that the force transfer between the foundation pit enclosure and the station main body structures and the underlying rock layer is clear and reliable, and a stable frame structure is achieved.
Abstract:
Combination of an open and a hidden excavation for constructing a vertical orthogonal top exhausting air duct structure of a deeply-buried subway station is provided. Four horizontal air ducts: left and right piston air ducts, an exhaust air duct, and a fresh air duct are thrown out of the underground, respectively, leading to left and right piston air shafts, an exhaust air shaft, a fresh air shaft, and an entrance/exit of fire-fighting. The fourth underground floor is communicated with the hall floor of the station main body, and the fifth underground floor is communicated with the running tunnel and the platform floor of the station main body. During operation, the train will enter and exit the station through the fifth underground floor of the air duct, and the piston air and heat will enter the four transverse air ducts through the air duct main body.
Abstract:
This invention provides a method and a terminal device for a multi-band antenna automatically tuning impedance matching, and belongs to the technical field of communication. The method includes: obtaining an operation current value and an output power value of a power amplifier upon transmitting a signal; obtaining a logical control parameter for controlling an antenna tuner based on the operation current value and the output power value, and adjusting the impedance matching of the antenna by using the logical control parameter. The efficiency for impedance matching of the antenna upon operating in the multi-bands may be improved, and the power saving can be better implemented under the condition of assuring the performance of the antenna.
Abstract:
An aerated swirling vertical shaft with double volute chambers comprises an upper volute chamber (2) and a first shrinking section (3) beneath the upper volute chamber (2), a venting passage (4) outside the upper volute chamber (2), a vertical shaft section (7) beneath the first shrinking section (3), as well as an aerated lower volute chamber (5) and a second shrinking section (6) communicated with the aerated lower volute chamber (5) between the first shrinking section (3) and the vertical shaft section (7), wherein the upper end of the aerated lower volute chamber (5) is connected with the first shrinking section (3), the lower end of the second shrinking section (6) is connected with the vertical shaft section (7); the upper end of the venting passage (4) is communicated with the atmosphere and the lower end is communicated with the aerated lower volute chamber (5). The water stream in the vertical shaft can be discharged smoothly and the wall surface of the vertical shaft may avoid being destroyed due to cavitation and cavitation erosion.
Abstract:
This invention provides a method and a terminal device for a multi-band antenna automatically tuning impedance matching, and belongs to the technical field of communication. The method includes: obtaining an operation current value and an output power value of a power amplifier upon transmitting a signal; obtaining a logical control parameter for controlling an antenna tuner based on the operation current value and the output power value, and adjusting the impedance matching of the antenna by using the logical control parameter. The efficiency for impedance matching of the antenna upon operating in the multi-bands may be improved, and the power saving can be better implemented under the condition of assuring the performance of the antenna.
Abstract:
A diode-pumped laser with a direct edge coupling of a pump beam is provided. The laser includes a microchip laser cavity optically pumped by a laser diode emitting an astigmatic pump beam having a substantially elliptical beam cross-section at an output laser diode facet. The microchip laser cavity is disposed at a substantial distance exceeding 0.001″ from the laser diode pump where the astigmatic pump beam has a greatly reduced ellipticity, providing high laser output efficiency without coupling lens element between the laser cavity and the laser diode pump. The pumping arrangement is favourable for single-mode lasing. In some embodiments, the laser cavity includes nonlinear crystal for intra-cavity SHG, a saturable absorber for passive Q-switching and mode locking, and a polarizing prism.
Abstract:
A delaminated subway station structure in a sea-land connection region includes an openly-excavated station hall, a platform floor, a first air shaft duct, a second air shaft, up and down entrances and exits, a barrier-free entrance and exit, and an under-rail street passage, where the platform floor is formed by expanding an existing running tunnel, such that a double-vault structure of the platform floor is formed; two groups of up and down entrances and exits are disposed, and located in waiting regions on two sides respectively to connect expanded ear chambers on two sides and the openly-excavated station hall; two groups of barrier-free entrances and exits are disposed, and located in the waiting regions on the two sides respectively; and the under-rail street passage is closely attached to a bottom plate of the existing running tunnel to form an underpass and connects to the expanded ear chambers.
Abstract:
A delaminated subway station structure in a sea-land connection region includes an openly-excavated station hall, a platform floor, a first air shaft duct, a second air shaft, up and down entrances and exits, a barrier-free entrance and exit, and an under-rail street passage, where the platform floor is formed by expanding an existing running tunnel, such that a double-vault structure of the platform floor is formed; two groups of up and down entrances and exits are disposed, and located in waiting regions on two sides respectively to connect expanded ear chambers on two sides and the openly-excavated station hall; two groups of barrier-free entrances and exits are disposed, and located in the waiting regions on the two sides respectively; and the under-rail street passage is closely attached to a bottom plate of the existing running tunnel to form an underpass and connects to the expanded ear chambers.
Abstract:
An aerated swirling vertical shaft with double volute chambers comprises an upper volute chamber (2) and a first shrinking section (3) beneath the upper volute chamber (2), a venting passage (4) outside the upper volute chamber (2), a vertical shaft section (7) beneath the first shrinking section (3), as well as an aerated lower volute chamber (5) and a second shrinking section (6) communicated with the aerated lower volute chamber (5) between the first shrinking section (3) and the vertical shaft section (7), wherein the upper end of the aerated lower volute chamber (5) is connected with the first shrinking section (3), the lower end of the second shrinking section (6) is connected with the vertical shaft section (7); the upper end of the venting passage (4) is communicated with the atmosphere and the lower end is communicated with the aerated lower volute chamber (5). The water stream in the vertical shaft can be discharged smoothly and the wall surface of the vertical shaft may avoid being destroyed due to cavitation and cavitation erosion.