Summary of the invention
The object of the present invention is to provide a kind of composite shield that is applicable to bad ground construction.The present invention solves the shield structure safe construction problem in Different Strata such as weak soil, decomposed rock, hard-soft heterogeneous ground, layer of sand and sand-pebble layer.
A kind of composite shield that is applicable to bad ground construction of the present invention comprises, cutterhead, shield shell, people cabin, belt conveyor, imitation-shaped knife, conveying worm and Tu Cang, and this shield structure also comprises:
Combined type cutterhead, described cutterhead are the combined type cutterhead, are fit to Different Strata constructions such as weak soil, hard rock, are separately installed with weak soil layer construction tool and ground consisting of hard rock construction tool on the cutterhead, change cutter when Different Strata is constructed;
Three kinds of excavation patterns are according to the excavation face stable mode of different geology employing its open mode, partial pressure pattern or earth pressure balance pattern;
The good system of quarrel land reform, by in cutterhead face, Tu Cang or conveying worm, injecting additive, and the rotation that utilizes cutterhead is stirred, native storehouse mixing plant stirs or conveying worm rotation stirring makes additive mix with the soil quarrel, and is good by the quarrel land reform, to adapt to different stratum.
The present invention is a kind of composite shield that is applicable to bad ground construction, also has following characteristics: the combined type cutterhead comprises cutterhead, wear rib, cutting knife, arc scraper, hobboing cutter and imitation-shaped knife; The cutterhead periphery is equipped with wear rib; Actiniform at least two row's grooves of the notch are arranged on cutterhead, two row's cutting knifes are installed in each bar groove of the notch, be positioned at the cutterhead edge in each row cutting knife end the arc scraper is installed; Between per two grooves of the notch of cutterhead periphery, peripheral openings is arranged, the arc scraper is arranged in each peripheral openings; On cutterhead, be cross arrangement and be provided with hobboing cutter, in the groove of the notch, between two row's cutting knifes imitation-shaped knife is installed.
Three kinds of excavation patterns are respectively:
(1) open type construction is stability rock stratum preferably at the excavation face, need not adjust native storehouse pressure, promptly the excavation face is not carried out the continuous pressure balance, and the shield structure cuts the quarrel soil that gets off and enters in the native storehouse and discharged by conveying worm at once;
(2) partial pressure pattern construction, the quarrel soil of maintenance 60%-70% native storehouse in runs into adjoining rock stability but is rich in phreatic stratum in the driving; The most of adjoining rock stability on the section of perhaps constructing, only there is the part stratum of decompression collapse can occur, perhaps zone of fracture, increase fltting speed in the hope of passing through fast this moment, and temporarily stop screw machine and be unearthed, close the screw machine gate that is unearthed, make the bottom of Tu Cang be full of quarrel stone, inject an amount of interpolation material and compressed air in excavation face and native storehouse, described interpolation material is foam, polymer, swell soil, mud or additive; And then the control screw machine slowly runs to guarantee forming " soil plug " in screw machine;
(3) earth pressure balance pattern construction, for excavating the formation stability difference or more phreatic weak soil or soft rock strata being arranged, the shield structure is in the driving excavation face soil body, the quarrel soil that tunnels is full of in the native storehouse, and make in the native storehouse quarrel soil density as far as possible with the tunnel excavation face on density of soil approaching; Under the thrust that advances oil cylinder, the quarrel soil that is full of in the native storehouse forms certain pressure, and quarrel soil pressure in the native storehouse and the water on the tunnel excavation face, soil pressure realize dynamic equilibrium.When adopting the earth pressure balance pattern, when differently the quality section is tunneled, add foaming agent, polymer, swell soil etc. as required to improve quarrel soil nature energy.
The good system of quarrel land reform comprises: soil pressure case, swell soil system interface, foam maker, foaming agent pump, water pump, foaming agent case and water tank, soil pressure case is installed on cutterhead, the swell soil system interface connects by pipeline, foam maker connects the swell soil system interface by pipeline, and the foaming agent case is connected the swell soil system interface through the foaming agent pump respectively with water tank with water pump.
A kind of composite shield that is applicable to bad ground construction of the present invention also comprises being with and compresses into the cabin security system; This system is made of main cabin, import cabin, excavation cabin and pressure-retaining system; The excavation freight space is in the cutterhead next door, and main cabin is connected with the excavation cabin, and main cabin is connected with the import cabin, between excavation cabin and main cabin, main cabin and the import cabin manhole door is arranged, and manhole door is closely closed; Pressure-retaining system connects the excavation cabin.
A kind of composite shield that is applicable to bad ground construction of the present invention, stable mechanism by excavation face in the research shield-tunneling construction, a kind of combined type earth pressure balanced shield, EPBS that has high-adaptability in bad ground is provided, at the characteristics of different geological conditionss, the safe construction system of energy simultaneous adaptation weak soil, decomposed rock, hard-soft heterogeneous ground, layer of sand and sand-pebble layer.
A kind of composite shield that is applicable to bad ground construction of the present invention, by adopting different excavation face stable modes and different cutter layouts and the good system of land reform that is cut to adapt to Different Strata, and design has band to compress into the cabin security system, can carry out the maintenance of inspection, replacing and other parts of cutter or the eliminating of underground obstacle safely and reliably fast.
Composite shield of the present invention, its geological adaptability is very wide, has broad application prospects in China.
The specific embodiment
With illustrated embodiments the present invention is done detailed explanation below:
Consult Fig. 1, a kind of composite shield that is applicable to bad ground construction comprises, cutterhead 1, shield shell 2, people cabin 3, belt conveyor 11, imitation-shaped knife 27, conveying worm 14 and native storehouse 42, and this system also comprises:
The combined type cutterhead, described cutterhead 1 is the combined type cutterhead, is fit to soft soil layer construction and ground consisting of hard rock construction, is separately installed with weak soil layer construction tool and ground consisting of hard rock construction tool on the cutterhead, changes cutter when Different Strata is constructed;
Three kinds of excavation patterns are according to the excavation face stable mode of different geology employing its open mode, partial pressure pattern or earth pressure balance pattern;
The good system of quarrel land reform, by in cutterhead face, Tu Cang or conveying worm, injecting additive, and the rotation that utilizes cutterhead is stirred, native storehouse mixing plant stirs or conveying worm rotation stirring makes additive mix with the soil quarrel, and is good by the quarrel land reform, to adapt to different stratum.
Consult Fig. 2 and Fig. 3, the combined type cutterhead comprises cutterhead 1, wear rib 19, cutting knife 22, arc scraper 24, hobboing cutter 26 and imitation-shaped knife 27; Cutterhead 1 periphery is equipped with wear rib 19; Actiniform at least two row's grooves of the notch 23 are arranged on cutterhead 1, two row's cutting knifes 22 are installed in each bar groove of the notch 23, be positioned at cutterhead 1 edge in each row cutting knife 22 end arc scraper 24 is installed; Between per two grooves of the notch 23 of cutterhead 1 periphery, peripheral openings 25 is arranged, in each peripheral openings 25, arc scraper 24 is arranged; On cutterhead 1, be cross arrangement and be provided with hobboing cutter 26, in the groove of the notch 23, between two row's cutting knifes 22 imitation-shaped knife 27 is installed.
Consult Fig. 4, Fig. 5 and Fig. 6, three kinds of excavation patterns are respectively:
(1) open type construction is stability rock stratum preferably at the excavation face, need not adjust native storehouse pressure, promptly the excavation face is not carried out the continuous pressure balance, and the shield structure cuts the quarrel soil that gets off and enters in the native storehouse and discharged by conveying worm at once;
(2) partial pressure pattern construction, the quarrel soil of maintenance 60%-70% native storehouse in runs into adjoining rock stability but is rich in phreatic stratum in the driving; The most of adjoining rock stability on the section of perhaps constructing only has the part stratum of decompression collapse can occur; Perhaps zone of fracture, increase fltting speed in the hope of passing through fast this moment, and temporarily stop screw machine and be unearthed, close the screw machine gate that is unearthed, make the bottom of Tu Cang be full of quarrel stone, inject an amount of interpolation material and compressed air in excavation face and native storehouse, described interpolation material is foam, polymer, swell soil, mud or additive; Controlling screw machine again slowly runs to guarantee forming " soil plug " in screw machine;
(3) or, the construction of earth pressure balance pattern, for excavating the formation stability difference or more phreatic weak soil or soft rock strata being arranged, the shield structure is in the driving excavation face soil body, the quarrel soil that tunnels is full of in the native storehouse, and make in the native storehouse quarrel soil density as far as possible with the tunnel excavation face on density of soil approaching; Under the thrust that advances oil cylinder, the quarrel soil that is full of in the native storehouse forms certain pressure, and quarrel soil pressure in the native storehouse and the water on the tunnel excavation face, soil pressure realize dynamic equilibrium.
Consult Fig. 7, the good system of quarrel land reform comprises: soil pressure case 29, swell soil system interface 31, foam maker 36, foaming agent pump 32, water pump 33, foaming agent case 34 and water tank 35, soil pressure case 29 is installed on cutterhead 1, swell soil system interface 31 connects 42 by pipeline, foam maker 36 connects swell soil system interface 31 by pipeline, and foaming agent case 34 is connected swell soil system interface 31 through foaming agent pump 32 with water pump 33 respectively with water tank 35.
Consult Fig. 8 and Fig. 9, a kind of composite shield that is applicable to bad ground construction also comprises being with and compresses into the cabin security system; This system is made of main cabin 37, import cabin 38, excavation cabin 39 and pressure-retaining system 40; Excavation cabin 39 is positioned at cutterhead 1 next door, and main cabin 37 is connected with excavation cabin 39, and main cabin 37 is connected with import cabin 38, between excavation cabin 39 and main cabin 37, main cabin 37 and the import cabin 38 manhole door is arranged, and manhole door is closely closed; Pressure-retaining system 40 connects excavation cabin 39.
The main frame of composite shield provided by the present invention mainly comprises: shield shell, cutterhead, cutter plate driver, conveying worm, belt conveyor, section of jurisdiction fitting machine, people storehouse etc.See Fig. 1.
Composite shield of the present invention, its cutterhead is the combined type cutterhead, sees Fig. 2 and Fig. 3.Adopting the combined type cutterhead is one of main feature of composite shield.The weak soil cutter both had been installed on cutterhead,, hard rock cutter (hobboing cutter) had been installed again as cutting knife and scraper, imitation-shaped knife.Arrange to adapt to Different Strata by different cutters.When soft soil layer was constructed, the hard rock hobboing cutter on the combined type cutterhead is replaceable to be cutter in advance (serrated knife, tear cutter or shell cutter).
Composite shield of the present invention has three kinds of excavation face stable modes (seeing Fig. 4,5,6).In shield-tunneling construction, can adopt different excavation face stable modes according to different geology.Two of the main feature that adopts various modes and can be composite shield according to the different conversion work patterns of geology.
Three kinds of excavation face stable modes are respectively its open mode, partial pressure pattern and earth pressure balance pattern, and each stable mode has different characteristics and suitable different stratum.
1) open type
Composite shield can adopt the open type construction in the face of the excavation face is a stability preferably during the rock stratum, need not adjust native storehouse pressure.The open type pattern generally is used for the stratum from the steady reasonable occasion of condition, even the excavation face is not carried out the continuous pressure balance, also can guarantee not unstability of excavation face at short notice, and the soil body does not cave in.Can adopt this pattern from the stratum steady, that underground water is few more.The shield structure cuts the quarrel soil that gets off and enters in the native storehouse and discharged by conveying worm at once, and the quarrel soil of minute quantity is only arranged in the native storehouse, and Tu Cang is in the state of emptying substantially, and the suffered anti-torsion of cutterhead and conveying worm is less in the driving.When adopting its open mode driving,, adopt high rotating speed, low moment of torsion and suitable conveying worm rotating speed to advance based on the broken rock of hobboing cutter; During synchronous grouting, slurries may seepage flow to space between shield shell and surrounding rock body even cutterhead place, can take suitably to increase slurry viscosity for avoiding this phenomenon to take place, shorten slurries time of setting, adjust method such as grouting pressure, section of jurisdiction additional slip casting behind and solve.
2) partial pressure pattern
Also claim semi-open-type.Composite shield has certain self-stability for the excavation mask, can adopt semi-open-type; The rotating speed of adjustable screw conveyer keeps about 2/3 quarrel soil in the native storehouse.If run into adjoining rock stability but be rich in phreatic stratum in the driving; The most of adjoining rock stability on the section of perhaps constructing only has the part stratum of decompression collapse can occur; Perhaps zone of fracture.Should increase fltting speed in the hope of passing through fast this moment, and temporarily stop screw machine and be unearthed, close the screw machine gate that is unearthed, make the bottom of Tu Cang be full of quarrel stone, in excavation face and native storehouse, inject an amount of interpolation material (as swell soil, mud or additive) and compressed air, the dense water of quarrel soil in the native storehouse is increased, also make simultaneously the interpolation material infilter excavation face stratum under pressure, on the excavation face, produce " the mud film " of one deck densification.By the generation of air pressure and the mud film prevention excavation face water burst and the phenomenon of caving in, control screw machine again and slowly run to guarantee in screw machine, forming " soil plug ", be can pass through this badness stratum safely and fast fully.Quarrel soil underfill Tu Cang in the driving in the native storehouse still has certain space, excavates face and prevents that underground water from infiltrating by input compressed air in native storehouse and the native together support of quarrel.This driving pattern is applicable to have certain self-stable ability and the not too high stratum of groundwater pressure, and its effect that prevents that underground water from infiltrating depends primarily on compressed-air actuated pressure, when the last soft construction of hard formation down adopts this pattern more.Breaking rock with hobboing cutter when last soft following hard formation is constructed is main broken hard rock, is the main cutting soil layer with serrated knife, scraper.When the river bed section is tunneled, need to add the sealing that foaming agent, polymer, swell soil etc. improve quarrel soil, so that the pressure stability balance in the native storehouse.
3) earth pressure balance pattern
Composite shield is bad or when more phreatic soft rock stratum is arranged for the excavation formation stability, needs to adopt the earth pressure balance pattern; Need the difference according to the stratum, front this moment, keeps different native storehouse pressure.
The shield structure is full of in the native storehouse quarrel soil that tunnel in the driving excavation face soil body, and make in the native storehouse the native density of quarrel as far as possible with the tunnel excavation face on density of soil approaching.Under the thrust that advances oil cylinder, the quarrel soil that is full of in the soil storehouse forms certain pressure, quarrel soil pressure in the soil storehouse and the water on the tunnel excavation face, soil pressure realize dynamic equilibrium, soil on the excavation face just can not collapse easily like this, reaches the unstability of not only finishing driving but also can not causing the excavation face soil body.
Pressure in the soil storehouse can be regulated by the driving speed of change shield structure or the rotating speed (deslagging amount soil) of screw machine, by measuring (comprising the mud material amount that adds) corresponding deslagging amount continuous excavation with shield structure digging soil, assurance makes digging soil amount corresponding with the deslagging amount, make the soil pressure of the creeping quarrel soil in the native storehouse can be all the time with the excavation face on water and soil pressure keep balance, the stability that keeps the excavation face, the pressure size obtains according to the pressure sensor that is installed on the native bulkhead, and screw machine rotating speed (casting amount) is regulated automatically according to the soil pressure that pressure sensor obtains.
When adopting the earth pressure balance pattern, be the main cutting soil layer, advance with the slow-speed of revolution, high pulling torque with serrated knife, cutting knife.The soil pressure value should be slightly larger than hydrostatic pressure and stratum soil pressure sum in the soil storehouse, when differently the quality section is tunneled, add foaming agent, polymer, swell soil etc. as required to improve quarrel soil nature energy, also the sealing pressurizer can be installed on conveying worm, so that the pressure stability balance in the native storehouse.
Composite shield of the present invention has the good system of quarrel land reform (see figure 7).Adopt the good system of quarrel land reform be composite shield the major technique characteristics three.
The good system of quarrel land reform is by injecting additive such as foam, swell soil or polymer etc. in cutterhead face, Tu Cang or conveying worm, and the rotation that utilizes cutterhead is stirred, native storehouse mixing plant stirs or conveying worm rotation stirring makes additive mix with the soil quarrel, good by the quarrel land reform, to adapt to different stratum.
The good system of quarrel land reform of composite shield can improve the native creeping of quarrel, improves sealing, reduces the cutterhead moment of torsion, reduces the wearing and tearing of knife disc tool and conveying worm, and to the good result of face sealing.
1. foaming system
Foaming system is mixed with a certain proportion of water by screw pump pumping foam, and through foam maker, the foaming of pressure-air blow pressure produces a large amount of foams, is transported to cutterhead front, Tu Cang or conveying worm by pipeline and mixes with quarrel soil.Foam has following advantage:
◆ because the lubricant effect of bubble has reduced the native angle of internal friction of quarrel, improve the flowability of quarrel soil, thereby reduced the moment of torsion of cutterhead, improved shield structure job parameter;
◆ reduce the permeability of quarrel soil, make whole spoil power transmission even, the face pressure fluctuation is little, helps adjusting native storehouse pressure, guarantees shield excavation attitude, the control ground settlement;
◆ reduce the viscosity of clay, help being unearthed;
◆ foam is nontoxic, can decompose disappearance voluntarily after 2 hours, and is pollution-free to soil environment.
Foaming system mainly comprises foaming agent jar, foaming agent pump, water pump, solution metering control valve, air dose control valve, fluid flowmeter, gas flowmeter, foam maker and connecting line.
The foaming agent pump pumps foaming agent from the foaming agent jar, and the water that pumps with water pump mixes formation solution in the ratio of shield structure driver operation instruction, control system is to measure the flow of water pump water outlet by the fluid flowmeter that is installed in the pump outlet place, and finishes this mixed proportion instruction according to the output quantity of this flow-control foaming agent pump.When mixed solution is fed forward, be assigned with and be transported in 4 pipelines, behind solution adjustable valve and fluid flowmeter, be transported in 4 foam makers again respectively, mix the generation foam with the compressed air that is transfused to simultaneously in foam maker, compressed air also will pass through gas flowmeter and air dose control valve earlier before entering foam maker.Foaming agent solution and compressed air also are to mix in the ratio of shield structure driver operation instruction, and this instruction needs to receive the information of fluid flowmeter and gas flowmeter and control the air dose control valve and the solution adjustable valve is finished by shield structure control system.At last, foam,, is injected in the excavation chamber again by the opening on the cutterhead by the cutterhead swivel joint along 4 pipelines.In the control room, operating personnel also can select arbitrarily from four pipelines as required, add foam to the excavation chamber.
2. swell soil system
The swell soil system comprises swell soil case, swell soil pump, pneumatic swell soil pipe-line control valve and connecting line.The shared 1 cover filling line of swell soil system and foaming system.
When needing to inject swell soil, swell soil by the swell soil pump along pipeline to front pump to the shield body, operating personnel can be as required, on the operating console in control room, by controlling the switch of pneumatic swell soil pipe-line control valve, swell soil is joined in excavation chamber, clay bin or the conveying worm.
3. polymer system
Polymer system utilizes this height of polymer bleed performance, makes the quarrel local products give birth to plasticity, is used to prevent to gush generation.Effect is more obvious aspect the generation that this system prevents to be cut in high hydraulic pressure Fu Shui stratum, water is gushed.Be used for hinged sealing place and Tu Cang.
Composite shield of the present invention has band and compresses into cabin security system (Fig. 8,9).Described people storehouse is the two chamber Ren Cang of two gas circuits, and the people storehouse is the pith that band is compressed into the cabin security system.For solving the risk of shield-tunneling construction, safely and reliably in the maintenance of depressing very much the inspection, replacing and other parts that carry out cutter fast or the eliminating of underground obstacle, composite shield of the present invention has adopted safe and reliable two gas circuit people storehouse and automatic pressure-retaining system.
Adopt the two chamber Ren Cang of two gas circuits when band is compressed into the cabin, personnel enter into the excavation cabin that is in high pressure from atmospheric area, should pass through the pressure period; Enter into atmospheric area from the excavation cabin that is in high pressure, should pass through decompression phase.Otherwise injured by air pressure, produce dysbarism.Must adopt the two chamber Ren Cang of two gas circuits so band is compressed into the cabin, the two chamber Ren Cang of two gas circuits have the airlock structure.Adding the decompression phase process carries out in airlock.
The airlock of the two storehouses, people from chamber of two gas circuits of shield structure and other form or the manned pressure vessel of other form are not had interchangeability.The two storehouses, people from chamber of two gas circuits of shield structure must adapt with the design feature of shield structure.
The two chamber Ren Cang of two gas circuits have at least two direct interconnected cabins to form.A cabin is as normal main cabin of reducing pressure, and a cabin is as the import cabin, and this cabin can be used as urgent decompression cabin.Main cabin is made up of the structure space in separate type cabin and the shield structure.Structure space in the shield structure by the excavation cabin partition wall and on every side steel work form, have plane coupling flange wall.The separate type cabin has two cabins.The separate type cabin connects by the flange wall in bolt and the shield machine, and seals with seal.On the corresponding wall in main cabin and import cabin manhole and manhole door are arranged, manhole door can closely be closed.The staff can open manhole door and enter into main cabin and import cabin or enter into the excavation cabin.
Be with the safety of compressing into cabin work for ensureing, the control system in the two storehouses, people from chamber of two gas circuits should have:
1) aerating, exhaust system.The equilibrium pressure that needs in the cabin is provided, breathe air is provided, ensure amount of fresh air.
2) fire fighting system.Prevent fire.Water fire fighting system and hand-held fire extinguisher are arranged.
3) air-conditioning system.The indoor air themperature of support module is in suitable scope.Suitable personnel carry out work.
4) gas pressure, temperature measurement system in the cabin.Measure display module indoor gas pressure, temperature in real time, be convenient to grasp the cabin personnel operation.The temperature that keep-ups pressure is in suitable scope.
5) communication system.Have explosion-proof communication system and acoustic energy communication system, ensure that each cabin is unimpeded with outside communication.
6) illumination and emergency lighting system.The time of emergency lighting should not be lower than 1 hour.
7) oxygen uptake system.Be used for the fast decompression process, or anoxic environment.
8) gas detecting analytical system.Whether pernicious gases such as check and analysis gas, carbon dioxide exceed standard, and whether oxygen content is suitable.
9) time display system.Be convenient to grasp add, activity duration of decompression time or staff.
Composite shield of the present invention has band and compresses into cabin auxiliary security guarantee control system.
According to the operating principle of shield method, compress into the safety of cabin work for ensureing band, the auxiliary security of airlock ensures that control system has:
1) mud injected system
With the quarrel soil in the special mud displacement excavation cabin, and at the comparatively stable mud film of the anterior formation of cutterhead.Make face have good impervious and firm performance.
2) air-pressure controlling system
Muddy water with the first half in the compressed air slurry displacement excavation cabin provides personnel working space.Ensure and breathe compressed-air actuated supply, guarantee to keep the pressure balance in the excavation cabin.
It is a kind of job that requires special skills mode that band is compressed into cabin work, should follow corresponding security step and measure.China does not also have the shield method band to compress into the technical specification file of aspect, cabin at present, and the scene is generally with reference to diving aspect technical specification.
Consult Figure 10, band is compressed into cabin safe procedures figure.
Compress into the cabin process at band, have according to concrete condition of construction what time to should be noted that:
1) chooses the qualified cabin personnel that advance.Advance the cabin personnel and not only should grasp into cabin job content, also should have good physical qualification.
2) operate according to the decompression table of science.
3) utilize mud to form the thicker impervious mud film of one deck, guarantee bubble-tight effect thereby reach at the excavation face.
4) compressed air pressure in the excavation cabin requires than calculating about the high 0.1~0.2bar of soil pressure.In the operation process that opens the cabin, should keep this pressure as far as possible, and the changing value of air pressure is controlled within the controlled range by the operation of admission valve; The compressed air that enters the excavation cabin should be to breathe compressed air.
5) determine the stability of excavation face by the Structural Engineer, whether need to carry out ground stabilization.
6) two above communication lines are set, in the storehouse that keep-ups pressure, the contact that reaches extraneous relevant departments outside the storehouse is unimpeded.
And establish the special messenger to ground monitoring and tour, and note abnormalities, in time ask processing for instructions.