US3813885A - Method for constructing an underground railway - Google Patents

Method for constructing an underground railway Download PDF

Info

Publication number
US3813885A
US3813885A US00144888A US14488871A US3813885A US 3813885 A US3813885 A US 3813885A US 00144888 A US00144888 A US 00144888A US 14488871 A US14488871 A US 14488871A US 3813885 A US3813885 A US 3813885A
Authority
US
United States
Prior art keywords
platform
tunnels
tunnel
carrier
gallery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00144888A
Other languages
English (en)
Inventor
J Tabor
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3813885A publication Critical patent/US3813885A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E21D9/06—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining
    • E21D9/08—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining with additional boring or cutting means other than the conventional cutting edge of the shield
    • E21D9/0875—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining with additional boring or cutting means other than the conventional cutting edge of the shield with a movable support arm carrying cutting tools for attacking the front face, e.g. a bucket
    • E21D9/0879—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining with additional boring or cutting means other than the conventional cutting edge of the shield with a movable support arm carrying cutting tools for attacking the front face, e.g. a bucket the shield being provided with devices for lining the tunnel, e.g. shuttering

Definitions

  • 61/44 tunnels are formed with the aid of an underground 922,768 5/1909 Jackson 61/44 tunneling machine housed in a shield. All tunnels have l HCSS substantially the ame profile 1,138,603 5/1915 Hallinger 61/42 1,899,474 2/1933 5 Claims, 7 Drawing Figures a, m 1 28 F25 O [91 J 8 Pmmimuu 4mm $813385 sum 1 s 1 INVENTOR Q 77150;
  • both the carrier tunnels and the platform stations are formed as a consecutive and gradually formed continuous gallery. No massive excavation through the overburden is required and the same tunneling machine which forms the carrier tunnels also forms the platform stations as tunnels with the same profile as the carrier tunnels. Accordingly, the problems encountered and created in massive excavation through the overburden are completely eliminated and tunneling momentum is maintained.
  • Structural tunnel elements are installed within the tunnel area in a repetitive building block fashion. Structural elements are prefabricated off-site with proper manufacturing procedures and quality control, thus reducing on-site labor and equipment congestion. The structural elements are fabricated to support the tunnel wall as well as the platforms and associated equipment.
  • Underground railways constructed according to the present invention have the added advantages that modifications in the platform station, such as extending the platforms to accommodate longer trains and heavier traffic loads, can be accomplished in ashort time with no work exterior of the existing tunnel walls, at low expense and with minimum disruption of continued operation of the subway system.
  • Tunnels embodying the present invention desirably have vertically stacked upper and lower traffic levels. Where tunnels intersect at the same grade level, means are provided to switch the traffic in one tunnel entirely into one level and traffic in the other tunnel to the other level, thus to avoid a grade crossing at the intersection. In some embodiments there are two parallel tracks on each level. In other embodiments there is one track on each level.
  • FIG. 1 is a diagrammatic view, partly in elevation and partly in vertical cross section through a subway system embodying the present invention at the location of a platfonn station and showing a townsite schematically at the surface level.
  • FIG. 2 is a vertical cross section taken along the line II-II of FIG. I.
  • FIG. 3 is a perspective view of a crossing or intersection between two carrier tunnels at equal level, portions of the tunnel walls being broken away to expose the interior.
  • FIG. 4 is a longitudinal section of a tunnel in the course of forming it with a shield mounted excavator.
  • FIG. 1 schematically illustrates a portion 1 of a town over a subway system embodying the present invention.
  • the town may include a canal 2 and has various buildings, etc., above the level of the ground surface.
  • subway or underground railway includes a station zone 3 which is underground.
  • Station zone 3 includes platform tunnels 4, 21 and carrier tunnels 5, 6.
  • the platform tunnel 4 is fonned consecutively with the carrier tunnels 5, 6.
  • Both the carrier tunnels 5, 6 and platform tunnel 4 have the same profile and are formed as one continuous gallery, for example by the tunneling mechanism shown in FIG. 4, and without requiring massive excavation through the overburden.
  • Each tunnel desirably has a horizontal partition 29 between upper and lower levels in the interconnecting tunnels, thus to form a floor for an upper track 10 at the top tunnel level.
  • the lower tunnel level has a floor for a track 9.
  • top and bottom loading platforms 7, 8 each of which extends for approximately one-half of the width of the tunnel, the other half being occupied by the tracks 10, 9.
  • the lower platform 8 communicates with the upper platfonn 7 by means of escalators 11.
  • Top platform 7 communicates with surface halls 14 of the station 3 by means of escalators 13 arranged in inclined tubes 12.
  • the top platform 7 may also communicate with the lower platform 18 of a crossing platform tunnel 21 which is at a higher non-intersecting level but which is substantially identical with platform tunnel 4, by means of escalators 16 arranged in inclined tube 15.
  • lower platform 18 is positioned along lower track 19 in tube 21 and communicates by means of escalators 22 with the top platform 17 positioned along the top track in tube 21.
  • Top platform 17 in tube 21 communicates with a surface hall 24 of station 3 by means of escalators 23.
  • each of the tracks 9, 10, 19, 20 and each of the platforms 8, 7, 18, 17 is positioned in a quadrant of its respective platform tunnel 4, 21.
  • Each quadrant offers a sufficient space for the clearance zone 26 of the rolling stock 25, as indicated in FIG. 2.
  • All tunnels are desirably built up of concrete liner blocks 27 as disclosed in my Canadian Patent 816,998 of July 8, 1969- This. ssaslri tisnjas uqssshq ld r sections 28fo r supporting the partition or floor 29. Far tition 29 supports the upper tracks and platform and also stiffens and re-enforces the tunnel structure.
  • two carrier tunnels 3t), 31 typically may intersect at the same level.
  • the tunnels have sufficient carrier space for providing an undisturbed or separated crossing for the tracks in the respective tun nel levels.
  • the floor partitions 38 in each tunnel intersect at the same level.
  • the top track 32 in quadrant 33 in tunnel 31 is diverted to one side to quadrant 34 and the bottom track 37 of the same tunnel 31 is brought upwardly on ramp 70 through an opening 73 in floor 38 onto floor 38, but in quadrant 33.
  • Lower track 39 in tunnel is also diverted to one side of the lower tunnel 40, from quadrant 40, to quadrant 41, and the top track 43 in quadrant 44 descends on ramp 70 into quadrant 40 at the lower floor level 42 of tunnel 30. Accordingly, the tracks will cross at different levels, thus avoiding conflict between traffic at the intersection of the two tunnels.
  • the tracks After passing through theintersection, the tracks return to their original levels and their original quadrants.
  • FIG. 7 illustrates an intersection similar to that shown in FIG. 3 but in which each of the carrier tunnels 30, 31 carry two tracks at each level, for a total of four tracks in each tunnel.
  • the elements which correspond to those in FIG. 3 are given the same reference characters.
  • track 370 at the lower level is located in quadrant 74 and parallels track 37 in quadrant 35.
  • Track 32a is provided in quadrant 34 at the upper level and parallels track 32 in quadrant 33.
  • track 39a at the lower level is located in quadrant 41 and parallels track 39 in quadrant 40.
  • Track 43a is provided in quadrant '75 at the upper level and parallels track 43 in quadrant 44.
  • switches 71 In order to transfer trains running on the additional tracks various switches 71 are provided whereby trains running on parallel tracks on one level of a tunnel can be transferred to a single track which passes through the zone of intersection of two tunnels as hereinbefore described in connection with FIG. 3. Operation of the switches may be automatically controlled to avoid conflict between trains.
  • crossing switches 72 which are disposed between parallel runs of the upper and lower tracks where they merge at the same level at the intersections of the tunnels.
  • FIG. 4 illustrates the manner of use of a shieldtunneling-drill 46 to construct tunnels suitable for use in the present invention.
  • a carrier tunnel 5 has previously been constructed. Its lining consists of arced liner blocks 45. A few of the liner blocks of platform tunnel 4 have already been positioned on an extension of carrier tunnel 5 in the gradually formed continuous gallery 47.
  • the shield-tunneling-drill 46 consists of a profiled hollow shield 48 provided with a cutting edge 49 and a skirt 50 sealed by means of a trailing annular sealing strip 51 at the outside of the liner blocks 45 which have already been positioned.
  • the shield 48 is closed by means of a transverse partition or bulkhead 52 immediately behind the digging wheel 53 which is mounted for rotation in the bulkhead.
  • Digging wheel 53 is driven by a motor 54 and has digging implements 55 and a hollow hub 56 provided with openings 60 through which the digging implements 55 discharge spoil.
  • a hopper 57 is positioned within the hub 56 and is mounted on the partition 52 and has an outlet 58 which can be closed by gate valve 59.
  • the parts 60 are sealed at the lower side of the hollow hub 56 by a stationary baffle or sea]- ing plate 61. Spoil delivered through outlet 58 is deposited down a ramp onto a spoil discharge conveying belt 62.
  • the liner blocks 45 are supplied by a conveyor belt 63 and are positioned in the tunnel wall by lifting and setting apparatus notshown. Jacks 64 press against positioned liner blocks 45 to force the shield 48 forwardly.
  • the shield 48 is thus advanced andspoil removed from the tunnel face by the cutting wheel 53, thus gradually elongating the gallery 47 from one carrier tunnel 5 or 6 through the platform tunnel 4 and therebeyond into the next carrier tunnel 5 or 6, and so on, without requiring any excavation from the surface.
  • platfonn tunnels 4 After the platfonn tunnels 4 are thus formed they are connected to the surface halls 14 by means of the inclined tube 12.
  • FIG. 5 illustrates a platform tunnel 4 to which carrier tunnels 5 are connected and in which the platform 8 occupies substantially the entire length of the platform section 4.
  • each level of each carrier tunnel is provided with two parallel tracks, such as tracks 37 and 370, as in FIG. 7.
  • Switches 71 are utilized to divert traffic from track 37 to track 370 within the platform tunnel 4, for loading purposes.
  • FIG. 6 illustrates an arrangement similar to that in FIG. 5, and also illustrates the technique for enlarging the platform tunnel section 4 from its extent indicated by the showing of platform 8 in full lines to its enlarged zone indicated by the platform extensions 8a shown in broken lines. All that is required is to move switches 71 longitudinally along the continuous tunnel gallery away from the platform 8 and to add the platform extensions 8a. No work exterior of the existing tunnel walls is required and these remain intact. The switches 71 can be installed during periods of light traffic, thus clearing the platform area for construction of the extensions 8a. Moreover, while construction work is being performed on one level .of the platform tunnel 4 it is possible to transfer traffic to the other level temporarily, as by the techniques illustrated in FIGS. 3 and 7 in which ramps are provided between two tunnel levels. Thus construction work can continue with minimum disruption of traffic.
  • H6. 4 is illustrative of one form of shield mounted excavating machine useful for forming the tunnels.
  • My US. Pat. Nos. 3,382,002 and 3,404,920 show other forms. In its broad aspects the invention is not limited to any particular form of tunneling machine.
  • a method for constructing an underground railway which includes spaced platform stations and interconnecting carrier tunnels, said method comprising the construction of both the platform stations and carrier tunnels as a substantially uniform profile continuous subsurface gallery fonned by continuously tunneling longitudinally of said gallery to form successively a carrier tunnel, a platform station, and another carrier tunnel at the other side of the platform station, installing laterally adjacent loading platforms and track in the platform station portions of said continuous gallery to define said platform stations and installing track in the carrier tunnel portions of said continuous gallery, and installing passenger ramps laterally into the platform stations portions of said continuous gallery.
  • the platform stations comprise tunnels communicating with the carrier tunnels, all said tunnels being formed with the aid of an underground tunneling machine housed in a shield which defines the cross sectional profile of all said tunnels.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Lining And Supports For Tunnels (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
US00144888A 1970-05-28 1971-05-19 Method for constructing an underground railway Expired - Lifetime US3813885A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL707007758A NL145914B (nl) 1970-05-28 1970-05-28 Ondergrondse spoorweg.

Publications (1)

Publication Number Publication Date
US3813885A true US3813885A (en) 1974-06-04

Family

ID=19810181

Family Applications (1)

Application Number Title Priority Date Filing Date
US00144888A Expired - Lifetime US3813885A (en) 1970-05-28 1971-05-19 Method for constructing an underground railway

Country Status (5)

Country Link
US (1) US3813885A (de)
CH (1) CH527081A (de)
ES (1) ES391632A1 (de)
GB (1) GB1339947A (de)
NL (1) NL145914B (de)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3990746A (en) * 1975-06-09 1976-11-09 Gewerkschaft Eisenhutte Westfalia Apparatus for and a method of storing and transporting lining sections in an underground tunnel driving installation
US5011331A (en) * 1988-11-25 1991-04-30 Armedio Clavarino Method and structural elements for construction underground garages
US20080033605A1 (en) * 2006-03-20 2008-02-07 Wolfgang Daum System and method for optimizing parameters of multiple rail vehicles operating over multiple intersecting railroad networks
USD629123S1 (en) * 2010-04-05 2010-12-14 Smith Sr Albert Lee Rocket train tube
US20110103893A1 (en) * 2009-10-30 2011-05-05 Silvino Pompeu Santos Tunnel multi floor
CN104925069A (zh) * 2014-03-18 2015-09-23 胡维民 地道列车
US9669851B2 (en) 2012-11-21 2017-06-06 General Electric Company Route examination system and method
US9682716B2 (en) 2012-11-21 2017-06-20 General Electric Company Route examining system and method
US9689681B2 (en) 2014-08-12 2017-06-27 General Electric Company System and method for vehicle operation
US9702715B2 (en) 2012-10-17 2017-07-11 General Electric Company Distributed energy management system and method for a vehicle system
US9733625B2 (en) 2006-03-20 2017-08-15 General Electric Company Trip optimization system and method for a train
US9828010B2 (en) 2006-03-20 2017-11-28 General Electric Company System, method and computer software code for determining a mission plan for a powered system using signal aspect information
US9834237B2 (en) 2012-11-21 2017-12-05 General Electric Company Route examining system and method
US9950722B2 (en) 2003-01-06 2018-04-24 General Electric Company System and method for vehicle control
CN108252722A (zh) * 2018-03-09 2018-07-06 上海市隧道工程轨道交通设计研究院 一种基于盾构法的上下叠双侧式车站结构及其应用方法
CN108313063A (zh) * 2018-03-09 2018-07-24 上海市隧道工程轨道交通设计研究院 一种上下叠双侧式盾构法车站的布置方法
CN109017816A (zh) * 2018-06-11 2018-12-18 中铁工程设计咨询集团有限公司 一种三层三纵群洞地下车站
US10308265B2 (en) 2006-03-20 2019-06-04 Ge Global Sourcing Llc Vehicle control system and method
US10569792B2 (en) 2006-03-20 2020-02-25 General Electric Company Vehicle control system and method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2344827B1 (es) * 2010-03-30 2011-06-28 Idelfonso Pablo Metro De Madrid, S.A. Metodo y sistema de transporte metropolitano.

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US804437A (en) * 1905-06-30 1905-11-14 James W See System of tunneling.
US899735A (en) * 1908-07-06 1908-09-29 George W Jackson Tunnel and subway.
US922768A (en) * 1908-07-06 1909-05-25 George W Jackson Underground subway for street-railways, &c.
US977306A (en) * 1910-09-26 1910-11-29 Edward B Hess Subway construction.
US1138603A (en) * 1914-05-02 1915-05-04 Franz Xaver Hallinger Method of building waterproof tunnels.
US1899474A (en) * 1930-11-29 1933-02-28 Ono Ryoe Method of constructing subway tunnels
US1981361A (en) * 1931-06-12 1934-11-20 Albert S Jones Crossing structure
US3319385A (en) * 1965-04-14 1967-05-16 Jack J Szpytman Parking garage for depressed roadways
US3386351A (en) * 1963-09-14 1968-06-04 Hara Shusaku System of grade separation and also underroad parking
US3410098A (en) * 1964-12-01 1968-11-12 Robbins & Assoc James S Tail section seals for shield tunneling machines

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US804437A (en) * 1905-06-30 1905-11-14 James W See System of tunneling.
US899735A (en) * 1908-07-06 1908-09-29 George W Jackson Tunnel and subway.
US922768A (en) * 1908-07-06 1909-05-25 George W Jackson Underground subway for street-railways, &c.
US977306A (en) * 1910-09-26 1910-11-29 Edward B Hess Subway construction.
US1138603A (en) * 1914-05-02 1915-05-04 Franz Xaver Hallinger Method of building waterproof tunnels.
US1899474A (en) * 1930-11-29 1933-02-28 Ono Ryoe Method of constructing subway tunnels
US1981361A (en) * 1931-06-12 1934-11-20 Albert S Jones Crossing structure
US3386351A (en) * 1963-09-14 1968-06-04 Hara Shusaku System of grade separation and also underroad parking
US3410098A (en) * 1964-12-01 1968-11-12 Robbins & Assoc James S Tail section seals for shield tunneling machines
US3319385A (en) * 1965-04-14 1967-05-16 Jack J Szpytman Parking garage for depressed roadways

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Engineering News Record June 17, 1926, Vol. 96, No. 24, Facing P. 974. *

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3990746A (en) * 1975-06-09 1976-11-09 Gewerkschaft Eisenhutte Westfalia Apparatus for and a method of storing and transporting lining sections in an underground tunnel driving installation
US5011331A (en) * 1988-11-25 1991-04-30 Armedio Clavarino Method and structural elements for construction underground garages
US9950722B2 (en) 2003-01-06 2018-04-24 General Electric Company System and method for vehicle control
US9733625B2 (en) 2006-03-20 2017-08-15 General Electric Company Trip optimization system and method for a train
US20080033605A1 (en) * 2006-03-20 2008-02-07 Wolfgang Daum System and method for optimizing parameters of multiple rail vehicles operating over multiple intersecting railroad networks
US8630757B2 (en) * 2006-03-20 2014-01-14 General Electric Company System and method for optimizing parameters of multiple rail vehicles operating over multiple intersecting railroad networks
US10569792B2 (en) 2006-03-20 2020-02-25 General Electric Company Vehicle control system and method
US10308265B2 (en) 2006-03-20 2019-06-04 Ge Global Sourcing Llc Vehicle control system and method
US9828010B2 (en) 2006-03-20 2017-11-28 General Electric Company System, method and computer software code for determining a mission plan for a powered system using signal aspect information
US20110103893A1 (en) * 2009-10-30 2011-05-05 Silvino Pompeu Santos Tunnel multi floor
USD629123S1 (en) * 2010-04-05 2010-12-14 Smith Sr Albert Lee Rocket train tube
US9702715B2 (en) 2012-10-17 2017-07-11 General Electric Company Distributed energy management system and method for a vehicle system
US9834237B2 (en) 2012-11-21 2017-12-05 General Electric Company Route examining system and method
US9682716B2 (en) 2012-11-21 2017-06-20 General Electric Company Route examining system and method
US9669851B2 (en) 2012-11-21 2017-06-06 General Electric Company Route examination system and method
CN104925069A (zh) * 2014-03-18 2015-09-23 胡维民 地道列车
US9689681B2 (en) 2014-08-12 2017-06-27 General Electric Company System and method for vehicle operation
CN108252722A (zh) * 2018-03-09 2018-07-06 上海市隧道工程轨道交通设计研究院 一种基于盾构法的上下叠双侧式车站结构及其应用方法
CN108313063A (zh) * 2018-03-09 2018-07-24 上海市隧道工程轨道交通设计研究院 一种上下叠双侧式盾构法车站的布置方法
CN108252722B (zh) * 2018-03-09 2024-01-30 上海市隧道工程轨道交通设计研究院 一种基于盾构法的上下叠双侧式车站结构及其应用方法
CN109017816A (zh) * 2018-06-11 2018-12-18 中铁工程设计咨询集团有限公司 一种三层三纵群洞地下车站

Also Published As

Publication number Publication date
CH527081A (de) 1972-08-31
ES391632A1 (es) 1974-06-01
NL145914B (nl) 1975-05-15
GB1339947A (en) 1973-12-05
NL7007758A (de) 1971-11-30

Similar Documents

Publication Publication Date Title
US3813885A (en) Method for constructing an underground railway
EP0334262B1 (de) Verfahren und Gerät zum Erweitern von Tunneln
US3266257A (en) Shield tunneling method and mechanism
UA125374C2 (uk) Спосіб розробки корисних копалин із самозбереженням під час безлюдного безціликового проведення штреку у виїмковій дільниці
CN110273688A (zh) 基于盾构法地铁与地下道路合建车站区间的布置施工方法
US4929123A (en) Method for building large span tunnels by means of a cellular arch
RU2015087C1 (ru) Способ ограждения хранилища отходов с помощью гидроизолирующего подземного устройства, охватывающего хранилище снизу и окружающего его со всех сторон, и установка для его осуществления
US3600899A (en) Shield tunneling apparatus
US3916630A (en) Tunneling methods and apparatus
US4029361A (en) Longwall mining roof support for double deck machines
US3631680A (en) Construction of tunnels
US4195886A (en) Radial mining method
EP0431909B1 (de) Herstellen einer Unterführung
CN110145314A (zh) 一种特大断面暗挖隧道高大核心土拆除的方法
US4072351A (en) Radial mining method
US2891778A (en) Long wall mining apparatus having a seam embracing channel
CN113006813B (zh) 在单一断面内融合地铁车站与区间的布局及机械化快速施工方法
SU1087670A1 (ru) Способ сооружени пересадочной станции метрополитена односводчатой конструкции
RU2122634C1 (ru) Способ разработки мощного крутого угольного пласта горизонтальными слоями
RU2734753C1 (ru) Станционный комплекс метрополитена мелкого заложения с единым центральным вестибюлем
SU1164425A1 (ru) Способ сооружени станционного узла метрополитена глубокого заложени
RU2843132C1 (ru) Способ сооружения объединенной пересадочной станции метрополитена глубокого заложения с подходящими к станции участками перегонных тоннелей
US3656810A (en) Tunneling shield
US4624504A (en) Method of excavating overburden in surface mining operations
CN113803072A (zh) 基于智能掘进机的厚大矿体非爆采矿方法