掘金基本知識(shí)（Nuggets basic knowledge）

1、掘金基本知識(shí)（Nuggets basic knowledge）Basic knowledge of tunnelingFirst, the position and function of tunnelingBoth mining and driving should be carried out first, so as to excavate and protect mining, and to promote mining by mining.Coal mining in driving the premise, driving and services in coal mining.T

2、wo, the basic concept of roadwayFrom the ground to the underground excavation engineering mainly includes wellbore, roadway and chamber of three parts.1. ShaftAccording to the slope: shaft, shaft, adit.According to the function: usually the main shaft (coal), auxiliary (materials, personnel transpor

3、t etc.), ventilation (ventilation), mixed well (coal, transportation etc.) etc.2 、 roadway1), according to the slope of horizontal roadway (drift, Shimen), inclined roadway (up and down);Shimen: refers to the vertical (or oblique) horizontal roadway heading in the coal seam.2) according to the coal

4、rock classification: rock roadway (section of rock accounted for 4/5 and above), coal roadway (section of coal seam accounts for 4/5 and above), semi coal roadway3) according to roadway categories: development roadway, preparation roadway, mining roadway4), according to the role of transport (such a

5、s working face roadway lane, belt rail hill hill, etc.), ventilation roadway (such as wind, wind up working face etc.), drainage (such as drainage lane water warehouse, etc.) and other roadways.3, chamberMine main pump room, transformer substation, winch room, depots, charging chamber, signal chambe

6、r, waiting room, avoid cave etc.4. Section shapeThere are two main categories of broken line shape (such as rectangle, trapezoid, oblique trapezoid, etc.) and curve (arch, circle, horseshoe, ellipse, etc.).There are mainly arch, trapezoid, rectangle (oblique rectangle), round, and other horseshoe sh

7、aped, elliptical, oblique trapezoidal, and so on. Mine mainly adopts arch, trapezoid, rectangle (oblique rectangle).The shape of each section is in order:The stability of the roadway and the pressure bearing force are as follows: circular, horseshoe, ellipse, arch, trapezoid, rectangle;The utilizati

8、on ratio of roadway section is trapezoidal, rectangle, arch, horseshoe and round;Construction difficulty: drilling and blasting method: trapezoid, rectangle, arch, horseshoe, round;The arch tunnel is mainly divided into straight wall semicircle arch, straight wall three center arch, straight wall ar

9、c arch, etc., for the bottom heave serious roadway also set the bottom arch. It is mainly used for roadway service with long service time, high pressure of roof and floor, preparation of roadway or mining roadway.The ladder is mainly used for roadway roof and floor pressure is not too big, pressure

10、is relatively large, Business Hours not too long roadway or roadway, sometimes also used for pressure roadway (especially small mine).Rectangular roadway is mainly used for roadway pressure is not too large, along the coal roadway heading and roadway preparation.The circular tunnel is mainly used fo

11、r shaft, power shaft, chamber, and the pressure and deformation of large roadway (soft rock tunnel) etc.Three 、 roadway support1, support formSingle support: mainly bolting and shotcrete (shotcrete) supporting, arching support and shed support;Combined support: mainly shotcrete shotcrete, anchor bea

12、m, frame support;Active support: bolt support, shotcrete (shotcrete) support, bolting and shotcreting supportPassive support: masonry-lining support, shed support, beam shotcrete;2, the main advantages and disadvantages of supporting formBolting and shotcrete (shotcrete) support and shotcrete suppor

13、t, can give full play to the role of the surrounding rock and the bearing capacity of surrounding rock and support, to form a whole structure, share the pressure of surrounding rock and deformation, is an active supporting method, with low cost,Easy to realize parallel cross operation, is conducive

14、to rapid construction of the organization. The application range is wide, and it is the main supporting form which is worth popularizing.Masonry-lining support, shed support, beam shotcrete: is a passive way of supporting, it mainly depends on the support of the surrounding rock under passive pressu

15、re and deformation, can not effectively play its role and bearing capacity of surrounding rock. It is not conducive to the rapid construction of the organization, the application conditions are limited, and can not be used as the main form of support, and can only be used in some specific roadway.3,

16、 the composition and construction of all kinds of support1) bolt supportThe classification of boltAccording to the anchoring method of bolt and supported rock mass, it can be divided into three types: mechanical, viscous and frictionAccording to anchorage location and length, it can be divided into

17、two types: end anchorage and full length anchorageAccording to the rod material, it can be divided into wood anchor, bamboo anchor, metal bolt, (reinforced) concrete bolt, glass fiber reinforced plastic anchor rod, etc.It is widely used in our mine, which belongs to bonded metal full length anchor b

18、olt.The bonded metal boltThe bonded bolt can be mainly divided into cement mortar, steel bar anchor and cement or resin anchoring reinforced bar anchor. Our mine is now using resin anchor bar anchor.The resin anchor bar is composed of resin capsule, rod body, supporting plate and nut.The anchor rod

19、body is used to bear the tension effect. The function of the support plate is to change the surrounding rock pressure into the pulling force of the anchor bolt; the function of the nut is to produce pre tightening force to prevent the surrounding rock from loosing and separating. The function of res

20、in capsule is to bond the rod with the surrounding rock well.There are two kinds of resin anchoring agents: medium speed and fast speed, the curing time of medium speed anchor is 4 6min, and the curing time of quick anchoring agent is 0.5 1min. Z stands for middle speed (like the original Z2350), an

21、d K stands for fast (as present MSK2360).Fast installation technology of anchor cable machine: anchor, quick anchoring agent stirring in place (anchoring agent stirring time 20 30s), cable machine stop stirring but not removed, wait for 1 minutes, or directly to fasten the anchor bolt nut, complete

22、the installation work.The three diameter matching of anchor rod refers to the size coordination relation between bolt hole diameter, anchor agent diameter and bolt diameter. General requirements: drilling diameter greater than anchor diameter 4 6mm (with the best 6mm), anchor diameter greater than a

23、nchor diameter 2 4mm.The construction of anchor pointsThe number of anchoring agent and mixing time must meet the requirements, so as to ensure the pulling force and anchoring effect of the anchor rod;The nut must be tightened, the torque meets the requirements, in order to ensure the pretension of

24、the bolt; at present, the torque of the anchor nut is 100N.m in our mine.The installation angle of anchor bolt should meet the requirement;Keep dry and clean inside the hole.2) shotcrete supportThe jet typeThere are two kinds of dry spray and wet spray. Dry jet is used in mine now.Dry shotcrete is a

25、 kind of dry mixed material which is sent to the nozzle by the pipe and sprayed into the rock surface after adding water to the nozzle. The main disadvantage of dry spray is the large dust.The sprayed concreteRaw materialsMainly cement, aggregate (sand, gravel), admixture (accelerator, water reducer

26、, early strength agent, waterproof agent, etc.), water.The addition rate of general accelerator is 2.5% 4%.RatioCement: aggregate (sand and gravel) = 1:4 1:4.5, sand in the aggregate accounted for 45% to 55%; that is, the usual cement: Sand: Stone = 1:2:2; water cement ratio is 0.4 0.45.The concrete

27、 construction pointsGrasp the ratio and water cement ratio well;2. Rinse the rock surface to be sprayed;Control the jet velocity and the distance between the lance head and the rock surface (the best is about 1m);Strengthen the maintenance: concrete should be maintained after 2h, not less than 7 day

28、s, every small class at least once.Strengthen the dust control of sprinkler, ventilation and individual protection.3) metal stentsThe classification1.According to the material: there are mainly mining I-beam metal support, mining U steel metal supportI-beam type: expressed by the height of the numbe

29、r of centimeters: such as 12 I-beam, that is, 12cm height.Model U steel: expressed by weight (kg) per metre, such as U29, which means that the U section steel is 29kg/m.According to the shape of the section, it is trapezoidal and archedAccording to the force and deformation properties, the retractab

30、le bracket and the non shrinking bracket are divided into two partsCombined with U type steel arch ribs, steel I-beam shaped rigid support is the most widely used.The U type steel arched yieldable supportAdvantages: the structure is simple, bearing capacity is larger, shrinkage performance is better

31、The support is composed of top beam, column leg, connecting piece, rack rod and backboard material.Symmetrical, straight leg, semicircle arch, three section bracket are used most. This form is adopted in my mine.The ladder shaped rigid support.It is mainly used in roadways with relatively stable sur

32、rounding rock, small deformation and low pressure.The support is composed of top beam, column leg, bracket rod and backboard material.Adding a middle column under the top beam can greatly improve the bearing capacity of the top beam.Finally, the supporting construction pointsStrictly control the emp

33、ty wall and leak roof;II. The supporting force uniform, trapezoidal support jianwo interface locking;The retractable bracket can be ensured. The shrinking, connecting pieces (cable clamp nut) matter; mine now provides cable clamp nut torque is 120N.m.The top and bottom bracket. The vertical drift, i

34、nclined angle of attack is reasonable.Four, roadway excavation construction(1) horizontal rock roadway constructionThere are two kinds of gun driving and machine digging, with more digging and more digging.The blasting, the general construction process are: drilling, blasting, loading, transport, ve

35、ntilation, rock bolting1, drilling1. Drilling machinery: drill (drill, hammers), commonly used air leg drill, with high frequency and low frequency points, the commonly used types are YT (7655) - 23, YT - 24, YT - 26, YTP - 26, mine is the main use of YT - 23.The drilling tool used. Qianzai, by dril

36、l (drill), drill rod (rod).The hole.According to the function and position: three kinds of cutting hole, auxiliary eye and peripheral eye.Cutting holeAction: increasing the free surface of blasting and improving the blasting effect.With inclinedchannel, straightslot, mixed cut three. Inclinedchannel

37、 and unidirectional cutting, multi direction cutting (split wedge and cone cut), generally shallow hole or hole blasting cut common wedge (or tapered slot), cutting method which is commonly used in mine.Auxiliary eyeIt is located between the cut hole and the surrounding eye, and its role is mainly t

38、he blasting rock mass.Peripheral eyeIt is located in the tunnel contour around the hole, the most important role is to ensure the formation of roadway.2. Charge blastingThe explosive.The use of coal mine explosive is ammonium nitrate explosive for industrial use.Coal mine must also use explosive for

39、 coal mine, mine is outburst mine, must use the security level is not less than three of the explosive for coal mine, coal and gas outburst danger working face, must use the security level is not less than three of the coal mine water bearing explosives.The detonator.The permissible instantaneous el

40、ectric detonator and permissible millisecond delay electric detonator are permissible for coal mine. The delay time of Millisecond Electric Detonator should not exceed 130ms, and only 15 millisecond electric detonators can be used in practical use.The charge.The charging structure has forward charge

41、 and reverse charge. For the high gassy mine, the positive charge is the best, that is, the explosive charge is located at the outermost part of the explosive charge, and the bottom of the detonator is facing the fundus).The line.There are three kinds of series, parallel, hybrid (series parallel, pa

42、rallel series), commonly used in series and series parallel more.The blasting.Millisecond blasting and smooth blasting are commonly used blasting techniques, especially the smooth blasting technology.3. VentilationTunneling is basically using local ventilation mode, pressing, drawing, mixed type thr

43、ee, tunneling ventilation should be used in general fan pressing (mine are), coal roadway outburst coal seam must use the press.4. Loading rockThere are two kinds of artificial rock loading and mechanical loading rock.Rock loader mainly includes rake bucket rock loader and bucket type rock loader.Th

44、e rake of the rake loader is 0.15, 0.3, 0.6, 0.9m3 and so on.Bucket loader has two types: rear unloading type and side discharging type.5, Yun YanThere are artificial or locomotive car transport, mechanical continuous transport (such as scraper conveyor, belt conveyor, etc.), mechanical continuous r

45、ock transport is the direction of development.It is the best choice to adopt the matching rock loading line.The main form of rock loading line is:Bucket back loading rock loader (or rake bucket loader) - ordinary mine car - small electric locomotive;Crab claw type loader - shuttle car - large motor

46、car.6, supportSee above.(two) coal roadway driving1, the characteristics of coal roadway drivingLarge amount of coal loading, long occupation time, loose or broken surrounding rock, easy roof accident, large gas volume, difficult ventilation management2, construction methodsThere are three kinds of

47、artificial, explosive and mechanical.3, mechanical construction (comprehensive excavation)Coal roadway mechanical tunneling construction with full mechanized tunneling and continuous mining machine tunneling.Coal roadway fully mechanized excavation function to realize the function of falling coal (P

48、o Yan), coal loading, coal transportation (transshipment), and supporting belt conveyor transport can achieve rapid tunneling construction. There are single cutting head and double cutting head in the comprehensive digging machine. The single cutting head fully mechanized digging machine is more fle

49、xible, which is beneficial to the arch section construction; the double cutting head comprehensive digging machine is more suitable for the coal roadway with small coal seam slope, rectangular or trapezoidal cross section.The existing continuous miner has been tunneling, and the tunneling speed is v

50、ery fast.(three) construction of semi coal and rock roadway1, we should pay attention to choose reasonable rock breaking position: there are three kinds of forms: picking top, undercover and picking top and undercover. Generally, it is better to use undercover instead of destroying the roof.2. Durin

51、g construction, the cutting holes are arranged in the coal seam.3, coal gangue can be divided into sub shipment or mixed shipment.(four) construction of up and down hill1. Driving up the hillThe shooting support can be easily damaged;It is difficult to manage the roof of steep inclined gable roof;3.

52、 It is easy to accumulate gas on the top of the mountain, so it is necessary to strengthen the ventilation management.Cutting holes are usually arranged at the bottom of the section.2, downhill drivingHead drainage is difficult;Transportation is more difficult and safety threat is bigger;The constru

53、ction of bottom hole is difficult, and the floor lift is easy to happen.4. The inclined tunnel transportation safety management and fire safety management (especially the misfire prevention and treatment) is the focus of construction safety management.(five) coal bunker construction in mining area1,

54、 bunker typeThere are vertical (generally round), inclined (slope generally in the range of 60 degrees to 70 degrees or more, the cross-section is generally round or arched.2, construction methodsThere are common anti - well method, drilling method, deep hole blasting method, etc. Drilling method is

55、 now widely used in construction.Drilling method: use drilling machine to drill a small hole from top to bottom, then use drilling machine from bottom to top brush into a small hole, and finally blasting method from top down the slim brush to the size of the design.(six), chamber and Intersection Co

56、nstruction1, the construction method of chamberA full cross section excavation method, bench work surface construction method, construction method of guide chamber.The whole section excavation method is generally applicable to the section is not too large, a height of not more than 4 5m chamber, and

57、 the use of large construction equipment.The bench working method has the method of working face and inverted step working face; the method of positive step working face has better safety, wider application range, and more commonly used. The method of working face is divided into 23 layers according to the height, the upper layer is advanced, and the lower layer is about 2m behind.The guide tunnel construction method is divided into small sections of whole section of more than 3, res