Timbering of anchor, net, gush is in fault is broken the application of the belt

  • Colliery timbering intermediary, read, timbering is in employ broken Mi newly to faced it and other timbering means to undertake comparative with tripartite of Liu Xiangzhi law.

    In not stable terrane or fault broken belt dig tunnel, with living timbering uses erect metal canopy or Xuan of build by laying bricks or stones. But the part that above all puts in inadequacy in in use of form of two kinds of timbering or actual construction. For this we are in broken belt popularizes fault timbering of applied anchor, net, gush, gained a success.

    The field of car of blind shaft of one 170 material that tunnel of construction of place of condition of 1 tunnel geology is rich force colliery, be apart from upper 410m. Tunnel total length is 120m, be in fault broken belt is 50m one paragraph medium. Following plan institute show the design section of tunnel.

    Tunnel timbering section designs country rock of sketch map tunnel to be layer of each other of shaly, sandstone, line having coal still is placed among, rock waits in belonging to consistence. But fall in the action of fault, the cliff system of broken belt is not stable, after tunnel dig if do not adopt any timbering, empty top is apart from when exceeding 1.5m produce a side, roof fall extremely easily.

    2 timbering parameter chooses 2.1 anchorage lever L I of length of 2.1.1 anchorage lever kind country rock N=0.9; N W of shellfish country rock kind country rock N=l.l; V kind country rock N=1.2, the fault of this tunnel is broken belt paragraph country rock belongs to V kind, n is taken for 1.2; Span of B ― tunnel, 4.2m. Data takes the place of, the option that gets gauze of gauze of D 2.2 of span of 2.1.2 anchorage lever must accord with the following requirement: ① net muscle must satisfy the requirement of intensity and stiffness, it is certain to have fight cut, the ability that defy a turn; ② manpower can make those who follow tunnel is vaulted bend, after originallying via anchorage lever anchor wall of can clingy alley; ③ mesh cannot pass small, lest eject protects the interior after Fu to appear intensity of layer of empty influence gush; ④ net piece size is proper, use in construction convenient, operate easily. Basis before use experience, we use the gauze of 4mm of net muscle diameter, norms is 1000 (Mm) , mesh norms is the practical experience of mining area of hillock of crane of basis of 2.3 eject concrete, according to tunnel service fixed number of year, span and country rock stability are classified established parameter of eject concrete ply, see next tables.

    10 years above serves cliff Wu fixed number of year fixed number of year 10 years the following kind clear span fastens li circumstance and fixed number of year of consideration tunnel service is in 30 years of above, ply of affirmatory eject concrete is 200mm too. Eject concrete must be divided second undertake. First first gush 100mm, install after anchorage lever hangs a net again answer gush 100mm achieves design ply. Do the effect that can have seasonable timbering so, avoid to produce a side, roof fall; Assure to install the safety when anchorage lever; Can make in gauze park sprinkler body, sufficient play gauze fights the action that cuts tension in concrete gush layer, carry the intensity of Dou concrete; Pass first of wall of gush fill alley uneven, make gauze can contact alley wall adequately, the acreage of exterior anchor solid that increases anchorage staff accordingly, promote ply of arch of consolidate of extruding of Dou country rock and quality.

    3 tunnel construction blows up with eye of pneumatic drill getting driving, make a bottle of loader smooth with a rake to install cliff to give Gan, with ZHP ― 2 model timbering of concrete of eject of rotor type spraying machine.

    Construction means uses 4 operation " two dig two gush " across undertakes. Namely a driving gives Gan, 2 install anchorage lever hangs net eject concrete, 3 driving give Gan, 2 install anchorage lever hangs net eject concrete, 3 driving give Gan, 4 install anchorage lever hangs net eject concrete. Such loop goes down. Should undertake anchorage gush timbering makes exercise of contented full circulation, in time working surface not leave a blank supports, circular plan is 1.2m surely. Driving ganger wants process: Working surface gets Gan of upside eye, outfit, working face to drill bottom eye and anchorage lever hole, blow up, undertake temporarily timbering. Timbering ganger wants process: Preparative work, install anchorage lever is hanged net and mix makings, gush working face supports for nothing first, the side top that answer gush hangs a net to be in, clear machinery and medicaments of eject spring back.

    Tunnel must use smooth face to blow up, the tunnel section outline after blowing up must accord with design requirement, create good condition to hang net eject concrete. Shorten as far as possible empty top time, the phenomenon that takes strict precautions against a side, roof fall happens, use U profiled bar in time vaulted canopy undertakes temporarily timbering. Gush must make tunnel section outline pliable first, at hanging with benefit the net is mixed answer gush. Beard of anchorage lever Kong Bi is perpendicular at tunnel contour line, before installing anchorage staff aspiration of hole bottom cuttings, anchorage solid agent coils must send hole bottom, the anchorage firm force of anchorage lever should achieve 40kN above. When answer gush in front gush does not want by the side of the net of 200m of certain put apart, so that mix,the net of below one loop undertakes building receiving. Answer gush ply should achieve 100mm, must not have the place of leakage gush absolutely.

    Economic effect is in 4 technologies not to stabilize terrane quite or fault is broken when taking dig tunnel, use timbering of anchorage, net, gush to compare timbering of the Xuan that use step and metallic canopy timbering, better in construction, technology and effect of economic tripartite side.

    Although can make tunnel serves growth of fixed number of year, pressure drop,use timbering of Xuan of build by laying bricks or stones small, do not need to undertake maintenance in use process, but its construction technology is sophisticated, the driving in construction process and timbering exercise are affected each other, need is done between working surface and Xuan of build by laying bricks or stones temporarily timbering, construction speed much, personnel provides slow, type of work much, salary expenses Dou, material is used up much, so unit cost Dou.

    Although personnel of simple, driving and timbering order operation, driving can hold construction craft concurrently to timbering works and make personnel provides rate of little, construction at the same time,use metallic canopy timbering fast, but cross fault with form of this kind of timbering the roof when broken belt accuses colliery timbering not easily to make, cause roof fall easily, pressure drop is big, and the following safeguard charge Dou, brush side top 12 every years afresh with respect to need, affect the normal production of mine, so unit cost also Dou. Accordingly, main carriage tunnel is unfavorable use form of this kind of timbering.

    And use timbering of afore-mentioned anchor, net, gush, its construction craft is simpler, and safe, reliable, service fixed number of years is long, do not need to undertake maintenance in use process, pressure drop is small, construction rate is rapid, personnel is deployed little, salary fare is low, material is used up little, unit cost is so low. But the integral quality of group of construction of requirement of this kind of timbering is higher, the construction quality of each working procedure must achieve design requirement.

    Major of coal mining of Wu bureau engineering college graduates. Currently hold the post ofcrane hillock mining industry (group) engineer of vice director of company development technical divisions. Postal (receive dysprosium v/LIT arrowhead to say period: 2004 ― 07 2005 year technology of timbering of countrywide colliery anchorage lever grooms teaching seminar held committee of mine timbering major in Nanjing in Nanjing " technology of timbering of countrywide colliery anchorage lever groomed 2005 teaching seminar " . Yuan of chairman of committee of major of timbering of colliery of association of Chinese coal industry and unripe professor chaired the meeting, science of institute of exploitation of Beijing of total courtyard of research of university of Chinese mining industry, coal science, coal studies more than 10 experts of site of place of courtyard of the Dou school such as company of group of mining industry of city of institute of total courtyard Nanjing and Xuzhou, Yan, new short of Wenshui River, scientific research, production, professor attends. Timbering of colliery of industry of deputy secretary-general of committee of major of timbering of colliery of association of Chinese coal industry, coal grooms Wang Fangrong of central vice director's researcher introduced above all countrywide colliery is anchorage since 2000 of lever timbering groom circumstance. Expert attending the meeting analysed current situation of timbering of anchorage lever of tunnel of our country colliery and the heat that solve urgently and difficulty problem seriously. Experts think consistently: Since this century, timbering of coal industry colliery grooms the anchorage lever timbering that the center holds every year grooms the class fostered spirit of technology of nearly 2000 timbering for the colliery, for anchor of tunnel of our country colliery the ceaseless progress of lever timbering technology produced positive effect. But our country colliery especially medium or small the integral technology level of timbering of colliery tunnel anchorage lever (guarantee system of standard of design, new material, construction, quality) as far apart as abroad, the safe state of tunnel timbering nots allow hopeful. Collect as our country colliery deep increase ceaselessly, dynamical calamity (concussion ground is pressed) the timbering security that gives tunnel caused bigger menace. Accordingly, experts appeal: The technology of timbering of colliery anchorage lever grooms should increase strength, want pair of mine not only Training Within Industry of one class technology, and should to division team team leader of the technical personnel of one class, district undertakes grooming, the academic level of personnel of technology of the basic level that carry Dou and district team leader and construction skill. Groom to carry Dou the quality of education, make student people acquire update more useful knowledge, will groom the class does so that have distinguishing feature more, the education content that experts groom to timbering of 25 years of anchorage lever, teaching material had serious research, made groom newly education outline.

    Basis of committee of major of timbering of colliery of association of Chinese coal industry Shijiazhuang first time only appoint meeting expert group and the opinion of seminar expert attending the meeting, the decision is held to the end of June from April 15, 2005 5 period timbering of anchorage lever of alley of countrywide colliery coal and cliff lane are fast driving grooms class (average class) , ran group company in August 2005 (bureau) , the seminar of chief Dou class of mine director driving and timbering.

    The seminar is right still groom of a teaching plan of each class, teaching materials write made specific research and division of labor respectively. After the meeting, timbering of coal industry colliery grooms the center begins to groom instantly according to the decision of the conference a specific preparation work. (Wang Fangrong offers sketch)