CN101215973A - Tunnel construction jet flow laneway ventilation method - Google Patents

Abstract

The invention belongs to a tunnel construction ventilation technology. The tunnel construction jet flow gallery ventilation method proposed is used for parallel double-hole tunnel construction. The pressurizing function of a jet fan is used to form main air current in the parallel double holes so that when fresh air enters and flows into an open transversal passage from one hole, pipe blowing ventilation is used to feed the fresh air at the upper part of the transverse passage to the working faces of the two holes; vitiated air flows back into the transverse passage from the working faces, and then flows out from the other hole. By adopting the jet flow gallery ventilation, the two parallel tunnel holes are used fully to feed the fresh air into the transverse passage from the entrance of the hole. Subsequently, the pipe blowing ventilation is used to feed the fresh air at the upper part of the transverse passage to the working faces. Compared with the simple pipe ventilation, the air supply distance of the air conduit is significantly reduced; the ventilation resistance and the dissipation of energy are reduced. In addition, transportation time is saved and potential safety hazards are reduced.

Description

Tunnel construction jet flow laneway ventilation method

Technical field

The invention belongs to the construction ventilation of tunnel technology, relate generally to a kind of tunnel construction jet flow laneway ventilation method, be used for the parallel double hole construction ventilation of super long tunnel.

Background technology

In the method for tunnel drilling and blasting work progress, produce blasting fume because of blowing out, therefore blasting fume causes the environment pollution of the scope of operation, influences the normal construction in tunnel, needs to adopt the mode of ventilation, and blasting fume is dropped to the concentration of permission, satisfies the workman and excavates the operation needs.Usually adopt the mode of pipe ventilated and dash, new wind is delivered to work plane,, create a reasonable construction environment in order to dilution and eliminating blasting fume.

For super long tunnel, very long because of the single port driving distance, determined new wind is delivered to from the hole distance of work plane, it is many always to leak out on the way.Compare with general short tunnel, provide the needed blower fan wind supply quantity of the identical air quantity of work plane big, the resistance on the way that blower fan will overcome is big.Therefore supporting Fan Equipment general power is big, and power consumption is big.

Construction ventilation of tunnel mainly adopts pipe ventilated and dash.The mode of pipe ventilated mainly contains forced, pull-out type and hybrid is as Fig. 1, Fig. 2, shown in Figure 3.Hybrid is forced and combining form pull-out type.Pipe ventilated is applicable to relatively shorter tunnel usually.Pipeline is divided into pneumatic hose and hard airduct.Pneumatic hose is generally used in forced ventilation, and hard airduct is generally adopted in exhaust ventilation.

Dash is used for the constructing tunnel in parallel double hole more, and needs pipe ventilated to match.The parallel double hole is meant two parallel tunnels, also can be a tunnel and a parallel service gallery.

As shown in Figure 4, in the dash, special main fan, air channel and air door to be set all usually.Air door is in order to prevent distinguished and admirable short circuit, simultaneously passing haulage vehicle to be passed through.The air channel links to each other with Ventilator Room, and main fan is positioned in the Ventilator Room.

For the super long tunnel in parallel double hole, if adopt existing draft type can have the following problem:

When adopting simple duct type air-supply, because be super long tunnel, the air supplying distance from the hole to the work plane is far, and used air supply duct is very long, and pipeline always leaks rather windy on the way, and the flowing resistance on the way that blower fan will overcome is also very big.Compare with general short tunnel, provide identical air quantity to work plane, the power consumption of ventilating is very big.

When adopting dash, then need to be provided with special main fan, air channel and air door.Though do not need very long ventilating duct, can solve the air-supply problem of long distance, increased the investment of air door, air channel and Ventilator Room.And because vehicle dealing transportation, air door needs frequent switch, and air door leaks rather windy, is generally 15%～20% of total blast volume, causes very big waste.Owing to when haulage vehicle passes through the twice air door, need slowly or pause, increased the muck removal haulage time, thereby reduced construction speed at every turn.Simultaneously, the existence of air door has also increased unsafe factor.

Summary of the invention

Purpose of the present invention promptly is to propose a kind of tunnel construction jet flow laneway ventilation method, reaches energy-conservation and increases work efficiency.

Method of ventilation proposed by the invention is used for the constructing tunnel in parallel double hole; It is a pressurization of utilizing jet blower, forms main airstream in the parallel double hole, fresh air is entered from a hole and when flowing the nearly transverse passage-way that opens wide, utilizes the pipeline forced ventilation fresh air of transverse passage-way upstream to be delivered to the work plane in two holes again; Foul atmosphere flows back to transverse passage-way from work plane, flows out from another hole again.

First transverse passage-way connects to whole parallel double is wide open and digs the construction of finishing between the parallel double hole, and its draft type is: in a hole jet blower is set therein, its drainage direction is inside; And two portable blowers are set in this hole and make them be positioned at the position of new perforation transverse passage-way rear portion 50-80 rice, wherein a portable blower is the tunnel scope of operation air-supply at its place by pipeline; Another portable blower institute connecting leg road enters another hole through transverse passage-way, is its scope of operation air-supply more forward; Along with the perforation of new transverse passage-way, the transverse passage-way at its rear portion all seals.

The present invention proposes to have the design formulas that matches with its method of ventilation, and in order to calculate hole air quantity, portable blower wind supply quantity, wind tube outlet air quantity and jet blower platform number, its design formulas is:

$\left\{\begin{array}{c}(R_{a1}+R_{b1}+R_h){Q_{\mathrm{ga}}}^2+(R_{a1}+R_{b1}){{\mathrm{<figure-callout\; id="2"\; label="Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{gb}}}^2+(R_{a1}+R_{b1}+R_{a2}+R_h){Q_{a2}}^2\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{\mathrm{gb}}+2\&CenterDot;(R_{a1}+R_{b1}+R_h)Q_{\mathrm{ga}}{Q}_{a2}\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{a2}-a_L(Q_{\mathrm{ga}}+Q_{\mathrm{gb}}+Q_{a2})-a_2=0\\ -F_1\left(Q_{\mathrm{ga}}\right)+(R_{\mathrm{ga}}+R_{a3}){Q_{\mathrm{ga}}}^2-R_{a2}{Q_{a2}}^2=0\\ -F_2\left(Q_{\mathrm{gb}}\right)-R_h{Q_{\mathrm{ga}}}^2+(R_{\mathrm{gb}}+R_{b2}){Q_{\mathrm{gb}}}^2-(R_h+R_{a2}){Q_{a2}}^2-2\&CenterDot;R_h{Q}_{\mathrm{ga}}{Q}_{a2}=0\end{array}\right.---\left(1\right)$

In the formula

R _A1---a hole from the hole to the windage of portable blower place section, kg.s ²/ m ⁸

R _A2---the windage of a hole from portable blower to unimpeded transverse passage-way, kg.s ²/ m ⁸

R _A3---the windage of a hole from unimpeded transverse passage-way to work plane, kg.s ²/ m ⁸

R _B1---the b hole from the hole to the windage of unimpeded transverse passage-way, kg.s ²/ m ⁸

R _B2---the windage of b hole from unimpeded transverse passage-way to work plane, kg.s ²/ m ⁸

R _Ga---be the windage of a hole scope of operation air-supply pipeline, kg.s ²/ m ⁸

R _Gb---be the windage of b hole scope of operation air-supply pipeline length, kg.s ²/ m ⁸

R _h---the windage of unimpeded transverse passage-way, kg.s ²/ m ⁸

Q _A1---the air quantity in from the hole to section a hole, portable blower place, m ³/ s;

Q _A2---the air quantity in from portable blower to unimpeded transverse passage-way a hole, m ³/ s;

Q _Ga---be the air quantity in a hole scope of operation air-supply pipeline, m ³/ s;

Q _Gb---be the air quantity in a hole scope of operation air-supply pipeline, m ³/ s;

Q _h---the air quantity in the unimpeded transverse passage-way, m ³/ s;

F ₁(Q _Ga)---portable blower a characteristic curve function;

F ₂(Q _Gb)---portable blower b characteristic curve function.

Derivation of equation process is as follows:

(1) engineering model

Be the derivation convenience of calculation, the parallel double hole is simplified, set up a representative engineering model.Suppose as follows:

Parallel double is respectively a hole and b hole, and two holes are driving forward simultaneously, and only from nearest unimpeded of work plane, other all seal the transverse passage-way that is communicated with the two.Transverse passage-way is perpendicular to two parallel tunnels.Wherein

A hole Excavation Length L _a, cross-sectional area A _a, wetted perimeter U _a

B hole Excavation Length L _b, cross-sectional area A _b, wetted perimeter U _b

The transverse passage-way length L _h, cross-sectional area A _h, wetted perimeter U _h

(2) derivation is calculated

Jet flow laneway ventilation is arranged as shown in figure 11.

The a hole is the air intake hole, and the b hole is a drain tunnel.Portable blower f _aBe the driving face air-supply in a hole, pipeline length L _Ga, caliber d _Ga, windage R _Ga, air quantity Q _GaPortable blower f _bBe the driving face air-supply in b hole, pipeline length L _Gb, caliber d _Gb, windage R _Gb, air quantity Q _GbAll blower fans all are placed in a hole, and jet blower is placed on after the portable blower.And the hypothesis air pipeline does not leak out.

The a hole is divided into three sections,

1 section: from the hole to portable blower place section, long L _A1, windage R _A1, air quantity Q _A1, blast h _A1

2 sections: from portable blower to unimpeded transverse passage-way, long L _A2, windage R _A2, air quantity Q _A2, blast h _A1

3 sections: from unimpeded transverse passage-way to work plane, length L _A3Windage R _A3, air quantity Q _A3

The b hole is divided into two sections,

1 section: from the hole to unimpeded transverse passage-way, length L _B1, windage R _B1, air quantity Q _B1

2 sections: from unimpeded transverse passage-way to work plane, length L _B2, windage R _B2, air quantity Q _B2

The windage R of unimpeded transverse passage-way _h, air quantity Q _h

Portable blower f _aBlast Δ P _Fa,

Portable blower f _bBlast Δ P _Fb,

At first, with reference to the form of circuit diagram, pass-out " ventilation diagram ", as shown in figure 12,

According to the pressure balance law

-ΔP _fb+h _gb+h _b2-h _h-h _a2＝0 (2)

-ΔP _fa+h _ga+h _a3-h _a2＝0 (3)

h _a1-ΔP _j+h _a2+h _h+H _b1＝0 (4)

According to the air balance law

Q _a1＝Q _b1＝Q _ga+Q _gb+Q _a2 (5)

Q _h＝Q _ga+Q _a2 (6)

Q _a3＝Q _ga (7)

Q _b2＝Q _gb (8)

Supercharging formula by jet blower gets

$\mathrm{\&Delta;}{p}_j={\mathrm{\&rho;<figure-callout\; id="2"\; label="V\; j"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">V</figure-callout>}}_j^{}\&CenterDot;\left(\frac{A_j}{A_a}\right)(1-\frac{v_{a1}}{V_j})\&CenterDot;k_j\&CenterDot;n_j$

$={\mathrm{\&rho;<figure-callout\; id="2"\; label="V\; j"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">V</figure-callout>}}_j^{}\&CenterDot;\left(\frac{A_j}{A_a}\right)(1-\frac{Q_{a1}}{A_a{V}_j})\&CenterDot;k_j\&CenterDot;n_j$

$={\mathrm{\&rho;V}}_j^2\left(\frac{A_j}{A_a}\right)\&CenterDot;k_j{n}_j-{\mathrm{\&rho;V}}_j\&CenterDot;\left(\frac{A_j}{{A_a}^2}\right)\&CenterDot;k_j\&CenterDot;n_j{Q}_{a1}$

$=a_1{Q}_{a1}+a_2---\left(9\right)$

Wherein, $a_1=-{\mathrm{\&rho;V}}_j\&CenterDot;\left(\frac{A_j}{{A_a}^2}\right)\&CenterDot;k_j\&CenterDot;n_j,$ $a_2={\mathrm{\&rho;V}}_j^2\left(\frac{A_j}{A_a}\right)\&CenterDot;k_j{n}_j$

In the formula: V _j-jet blower outlet wind speed, m/s;

A _j-jet blower discharge area, m ²

k _j-supercharging coefficient;

n _j-jet blower platform number, platform.

Characteristic curve according to portable blower gets

ΔP _fa＝F ₁(Q _ga) (10)

ΔP _fb＝F ₂(Q _gb) (11)

According to the flowing resistance law

$R_{a1}{Q_{a1}}^2-a_1{Q}_{a1}-a_2+R_{a2}{Q_{a2}}^2+R_{\mathrm{<figure-callout\; id="2"\; label="h\; Q\; h"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">h</figure-callout>}}{Q_h}^{}{{}_{}}^2+R_{b1}{{\mathrm{<figure-callout\; id="1"\; label="Q\; b"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_b}^2=0---\left(12\right)$

$-F_1\left(Q_{\mathrm{ga}}\right)+R_{\mathrm{ga}}{Q_{\mathrm{ga}}}^2-R_{a3}{Q_{a3}}^2-R_{a2}{Q_{a2}}^2=0---\left(13\right)$

$-F_2\left(Q_{\mathrm{gb}}\right)+R_{\mathrm{<figure-callout\; id="2"\; label="gb\; Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">gb</figure-callout>}}{Q_{\mathrm{gb}}}^{}{{}_{}}^2+R_{b2}{{\mathrm{<figure-callout\; id="2"\; label="Q\; b"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_b}^2-R_h{Q_h}^2-R_{a2}{Q_{a2}}^2=0---\left(14\right)$

(5) (6) (7) (8) formula substitutions (12) (13) (14) formula is got

$\left\{\begin{array}{c}(R_{a1}+{\mathrm{<figure-callout\; id="1"\; label="R\; b"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">R</figure-callout>}}_b+R_h){{\mathrm{<figure-callout\; id="2"\; label="Q\; ga"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{ga}}}^2+(R_{a1}+R_{b1}){{\mathrm{<figure-callout\; id="2"\; label="Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{gb}}}^2+(R_{a1}+{\mathrm{<figure-callout\; id="1"\; label="R\; b"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">R</figure-callout>}}_b+R_{a2}+R_h){Q_{a2}}^2\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{\mathrm{gb}}+2\&CenterDot;(R_{a1}+{\mathrm{<figure-callout\; id="1"\; label="R\; b"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">R</figure-callout>}}_b+R_h)Q_{\mathrm{ga}}{Q}_{a2}\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{a2}-a_1(Q_{\mathrm{ga}}+Q_{\mathrm{gb}}+Q_{a2})-a_2=0\\ -F_1\left(Q_{\mathrm{ga}}\right)+(R_{\mathrm{ga}}+R_{a3}){Q_{\mathrm{ga}}}^2-R_{a2}{Q_{a2}}^2=0\\ -F_2\left(Q_{\mathrm{gb}}\right)-R_{\mathrm{<figure-callout\; id="2"\; label="h\; Q\; ga"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">h</figure-callout>}}{Q_{\mathrm{ga}}}^{}{{}_{}}^2+(R_{\mathrm{gb}}+R_{b2}){Q_{\mathrm{gb}}}^2-(R_h+R_{a2}){Q_{a2}}^2-2\&CenterDot;R_h{Q}_{\mathrm{ga}}{Q}_{a2}=0\end{array}\right.---\left(15\right)$

The group of solving an equation (15) formula gets Q _Ga, Q _Gb, Q _A2, substitution (5), (6) formula get Q _A1, Q _h

The present invention adopts jet flow laneway ventilation, can make full use of two parallel tunnels, and fresh wind is delivered to transverse passage-way from the hole, and then utilizes the pipeline forced ventilation that the new wind of transverse passage-way upstream is delivered to work plane.Simple relatively pipe ventilated has shortened the air supplying distance of airduct greatly, has reduced flowing resistance, has reduced power consumption; There is not the problem of leaking out because the tunnel does not resemble airduct in addition, reduced total wind supply quantity.Main fan dash has relatively saved air channel and air door, has reduced input, owing to there has not been air door, does not have the problem of leaking out in addition, has reduced total wind supply quantity, has reduced power consumption.Save haulage time simultaneously and reduced potential safety hazard.

Draft type proposed by the invention does not need main fan, Ventilator Room, air channel and air door, does not need very long air supply duct yet; Have energy-conservation and characteristics high efficiency.

Description of drawings

Fig. 1 is existing pipeline forced ventilation schematic diagram.

Fig. 2 is existing pipeline exhaust ventilation schematic diagram.

Fig. 3 is existing pipeline compound ventilation schematic diagram.

Fig. 4 is existing ventilation by ducts schematic diagram.

Fig. 5 is construction incipient stage forced ventilation schematic diagram.

Fig. 6 is a jet flow laneway ventilation schematic diagram of the present invention.

Fig. 7 is the inventive method phase I schematic diagram.

Fig. 8 is the inventive method second stage schematic diagram.

Fig. 9 is the inventive method phase III schematic diagram.

Figure 10 is the inventive method N stage schematic diagram.

Figure 11 arranges schematic diagram for jet flow laneway ventilation of the present invention.

Figure 12 is a jet flow laneway ventilation ventilation diagram of the present invention.

Among the figure: 1, portable blower 2, pneumatic hose 3, tunnel 4, tunneling operation face 5, new wind 6, dirty wind 7, hard airduct 8, a hole 9, b hole 10, portable blower a 11, portable blower b 12, pipeline a 13, pipeline b 14, a hole scope of operation 15, the b hole scope of operation 16, transverse passage-way 17, air channel 18, Ventilator Room 19, main fan 20, air door 21, jet blower 22, first transverse passage-way 23, second transverse passage-way 24, the 3rd transverse passage-way 25, a N-1 transverse passage-way 26, a N transverse passage-way

The specific embodiment

Providing embodiments of the invention is illustrated method of ventilation of the present invention:

As shown in Figure 5, the tunnel excavate forward just promptly first transverse passage-way between two holes non-through before, two holes are provided with a portable blower respectively and adopt the pipeline forced ventilation, promptly two portable blowers are arranged on outside the hole and blow by the corresponding tunnel scope of operation by pipeline.

As shown in Figure 6, first transverse passage-way connects to whole parallel double is wide open and digs the construction of finishing between the parallel double hole, and its draft type is: in a hole jet blower is set therein, its drainage direction is inside; And two portable blowers are set in this hole and make them be positioned at the position of new perforation transverse passage-way rear portion 50-80 rice, wherein a portable blower is the tunnel scope of operation air-supply at its place by pipeline; Another portable blower institute connecting leg road enters another hole through transverse passage-way, is its scope of operation air-supply more forward; Along with the perforation of new transverse passage-way, the transverse passage-way at its rear portion all seals.

It specifies as follows:

As shown in Figure 7, after first transverse passage-way connects between parallel two holes, in a hole, install a jet blower, the injection direction is inside, two portable blowers all are arranged in this hole and are arranged on position from about 50 meters of transverse passage-ways, be the scope of operation air-supply of a hole before the portable blower institute connecting leg road direction, another portable blower institute connecting leg road enters the b hole through transverse passage-way, is forward the scope of operation air-supply of b hole again.

As shown in Figure 8, after second transverse passage-way connects between parallel two holes, jet blower still is arranged on original position or reach, its injection direction is constant, and two portable blowers move forward in former hole apart from the position of about 50 meters of second transverse passage-ways, and institute connecting leg road is constant, a portable blower goes ahead by pipeline and is the air-supply of a hole scope of operation, the pipeline of another portable blower enters the b hole through transverse passage-way and is the air-supply of the b hole scope of operation more forward, simultaneously, and first transverse passage-way sealing.

As shown in Figure 9, after the 3rd transverse passage-way connects between parallel two holes, jet blower still is arranged on original position or reach, the injection direction is constant, increase a jet blower (the platform number of jet blower is drawn by design formulas) in the hole again, two portable blowers move forward in Yuan Dong (a hole) apart from the position of about 50 meters of the 3rd transverse passage-ways, institute connecting leg road is constant, a portable blower pipeline goes ahead and directly is the air-supply of a hole scope of operation, another portable blower pipeline enters another hole through transverse passage-way, be forward this hole scope of operation air-supply again, simultaneously, second transverse passage-way sealing.

As shown in figure 10, and the like, after N transverse passage-way connects, the jet blower that in a hole, is provided with (its number is drawn by design formulas) still in position or the reach, two portable blowers progressively move forward in a hole apart from the position of about 50 meters of N transverse passage-ways, institute connecting leg road is constant, a portable blower institute connecting leg road goes ahead and is the air-supply of a hole scope of operation, another portable blower institute connecting leg road is in transverse passage-way enters the b hole, be forward the scope of operation air-supply of b hole again, N-1 transverse passage-way sealing finished up to tunnel excavation simultaneously.

Be that example is specified jet flow laneway ventilation method of the present invention and design formulas with circular beam mountain super long tunnel more below:

Yuanliangshan Tunnel total length 11068m, flat lead with positive hole in distance between centers of tracks 30m, every about 410m, establish a transverse passage-way, amount to 26.It is DK355+820 that work area boundary mileage is imported and exported in the tunnel.The long 4355m in import work area, about 10 transverse passage-ways; The outlet long 6713m in work area.Import and export the work area and be drill bursting construction, rail transportation.The positive hole peace of circular beam mountain super long tunnel is led, and just in time forms the parallel double hole.

Calculating section

(1) control air quantity

The section size of leading according to the positive hole of Yuanliangshan Tunnel peace, explosive consumption and other have related parameter, and the control air quantity that calculates ventilation is:

1. lead full advance for putting down, by ventilation length 200m, ventilation time considered that face institute required airflow was 536m in 10 minutes ³/ min (is 8.93m ³/ s);

2. for the full advance of positive hole, by ventilation length 200m, ventilation time considered that face institute required airflow was 938m in 20 minutes ³/ min (is 15.63m ³/ s).

Because tunnel gas content is lower, lead and during positive hole ventilated, the used air quantity of dilution gas all was not the control air quantity flat.

(2) the airduct air outlet should have air quantity

The air quantity that should have of flat guide duct air outlet should be more than or equal to 8.93m ³/ s; The air quantity that should have of positive hole airduct air outlet should be more than or equal to 15.63m ³/ s.

(3) blower fan is answered the initial option of wind supply quantity and portable blower and airduct

According to air-conditioning requirement, tentatively being chosen for flat dust diameter of leading the air pipeline of work plane air-supply is 1000mm, and maximum air supplying distance is 1350 meters considerations, hundred meters air leak rate of air curtain β＜1.5%.

Then blower fan answers wind supply quantity to be

Q _fa＝Q ₀·(1-β _a) ^-13.5＝10.95m ³/s

With reference to fan performance curve figure, tentatively determine portable blower f _aBe SDF (A)-№ 6.5 type blower fans

The dust diameter that tentatively is chosen for the air pipeline of positive hole work plane air-supply is 1200 millimeters, and maximum air supplying distance is 600 meters, hundred meters air leak rate of air curtain β＜2%.

Then blower fan answers wind supply quantity to be

Q _fb＝Q ₀·(1-β _b) ^-6＝17.64m ³/s

Preliminary definite portable blower f _bBe SDF (A)-№ 10 type blower fans.

(4) should go into the initial option of hole air quantity and jet blower

Owing to equal the wind supply quantity sum of leading with positive hole blower fan of answering be

Q _fb+Q _fa＝28.59m ³/s

Therefore, should go into the hole air quantity more than or equal to 28.59m ³/ s.

Tentatively choosing jet blower is SSF-№ 12 type blower fans.

(5) go into the calculating major parameter of hole air quantity, portable blower wind supply quantity, wind tube outlet air quantity and jet blower platform number

1. connect the distance of transverse passage-way to the hole

X is respectively 410,820,1230,1640,2050,2460,2870,3280,3690,4100,4510,4920,5330m,

Other major parameters are

2. tunnel a

L _A1Be respectively 310,720,1130,1540,1950,2360,2770,3180,3590,4000,4410,4820,5230m;

L _a2＝100m，L _a3＝1280m，A _a＝13.552m ²，U _a＝14.007m；

Coefficient of frictional resistance α _a=0.0195;

Air intake coefficient of partial resistance ξ _In=0.6.

3. tunnel b

L _B1Be respectively 410,820,1230,1640,2050,2460,2870,3280,3690,4100,4510,4920,5330m.

L _b2＝500m，A _b＝45.8m ²，U _b＝23.308m；

Coefficient of frictional resistance α _b=0.0039,

Air outlet coefficient of partial resistance ξ _Out=1.0.

4. transverse passage-way

L _h＝30m，A _h＝13.552m ²，U _h＝14.007m；

Coefficient of frictional resistance α _h=0.0195;

The transverse passage-way coefficient of partial resistance is ξ ₁=2.0, ξ ₁=2.6.

5. air pipeline

L _ga＝1350m，L _gb＝600m，d _ga＝1.0m，d _gb＝1.2m；

Coefficient of frictional resistance α _Ga=0.003, α _Gb=0.003;

Air pipeline b is at the coefficient of partial resistance ξ at transverse passage-way place ₃=0.18, ξ ₄=0.18.

6. jet blower

The Specifeca tion speeification of SSF-№ 12 jet blowers is

V _j＝33.3m/s，A _j＝1.1304m ²，k _j＝0.85。

7. atmospheric density

ρ＝1.20kg/m ³。

8. the air pressure air flow relational expression of portable blower

Performance curve according to portable blower SDF (A)-№ 6.5 gets

$\mathrm{\&Delta;}{P}_{\mathrm{fa}}=F_1\left(Q_{\mathrm{ga}}\right)$

$=5.1466966764E-07{Q_{\mathrm{ga}}}^4-1.3943207446E-03{{\mathrm{<figure-callout\; id="3"\; label="Q\; ga"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{ga}}}^3+1.3358049359E+00{{\mathrm{<figure-callout\; id="2"\; label="Q\; ga"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{ga}}}^2$

$-5.4493670570E+02Q_{\mathrm{ga}}+8.4534521907E+04+\frac{8\mathrm{\&rho;}}{{\mathrm{\&pi;}}^2{d_{\mathrm{ga}}}^4}{{\mathrm{<figure-callout\; id="2"\; label="Q\; ga"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{ga}}}^2$

Performance curve according to portable blower SDF (A)-№ 10 gets

$\mathrm{\&Delta;}{P}_{\mathrm{fb}}=F_2\left(Q_{\mathrm{gb}}\right)$

$=-4.0471097212E-08{{\mathrm{<figure-callout\; id="4"\; label="Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{gb}}}^4+1.8234324433E-04{Q_{\mathrm{gb}}}^3-3.0950128478E-01{{\mathrm{<figure-callout\; id="2"\; label="Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{gb}}}^2$

$+2.3100271008E+02Q_{\mathrm{gb}}-6.0040938515E+04+\frac{8\mathrm{\&rho;}}{{\mathrm{\&pi;}}^2{d_{\mathrm{gb}}}^4}{{\mathrm{<figure-callout\; id="2"\; label="Q\; gb"\; filenames="S2007103048549E00011.png"\; state="\{\{state\}\}">Q</figure-callout>}}_{\mathrm{gb}}}^2$

Result of calculation

Calculate the windage of each section of tunnel, windage and other relevant parameter of air pipeline respectively according to above parameter.Substitution equation group then (1), the group of solving an equation just can obtain the air quantity asked.

To connect transverse passage-way to the tunnel mouth be different value apart from x the time air quantity when calculating, count n by adjusting the jet blower platform _j, make flat air quantity of leading second section greater than zero all the time, in order to avoid unnecessary dirty wind circulation occurs.According to standard, flat wind speed of leading second section should be not less than 0.25m/s, and corresponding air quantity is not less than 3.39m ₃/ s when influencing (do not consider airduct).But only otherwise have the circulation of dirty wind, can result of calculation see Table 1 greater than zero.

Table 1 Yuanliangshan Tunnel Design of ventilation result of calculation

Unimpeded transverse passage-way to the hole apart from x (m)	The jet blower platform is counted n j(platform)	Portable blower a air quantity Q ga(m 3/s)	Flat guide duct outlet air quantity (m 3/s)	Portable blower b air quantity Q gb(m 3/s)	Positive hole wind tube outlet air quantity (m 3/s)	The tunnel a second section air quantity Q a2(m 3/s)	Tunnel a the 1st section air quantity Q a1(m 3/s)	Jet blower injection air quantity Q j(m 3/s)
									410	0.5	11.17	9.17	21.12	18.71	0.87	33.16	22.25
820	1.1	11.17	9.17	21.12	18.71	1.27	33.56	26.42
									1230	1.6	11.17	9.17	21.12	18.71	0.48	32.77	27.40
1640	2.1	11.17	9.17	21.12	18.71	0.07	32.36	27.96
									2050	2.7	11.17	9.17	21.12	18.71	0.40	32.69	28.82
2460	3.2	11.17	9.17	21.12	18.71	0.14	32.43	29.00
									2870	3.8	11.17	9.17	21.12	18.71	0.37	32.66	29.50
3280	4.3	11.17	9.17	21.12	18.71	0.18	32.47	29.56
									3690	4.8	11.17	9.17	21.12	18.71	0.03	32.32	29.60
4100	5.4	11.17	9.17	21.12	18.71	0.20	32.49	29.90
									4510	5.9	11.17	9.17	21.12	18.71	0.08	32.36	29.91
4920	6.5	11.17	9.17	21.12	18.71	0.21	32.50	30.14
									5330	7.0	11.17	9.17	21.12	18.71	0.11	32.40	30.13

Illustrate: the injection air quantity of jet blower is that the work air quantity at the hypothesis portable blower is zero (Q _Ga=0, Q _Gb=0), calculates under the constant situation of other conditions.

(6) determine jet blower, portable blower and airduct

Result of calculation from table 3-1 as can be seen, along with the peaceful work plane of leading in positive hole is pushed ahead, unimpeded transverse passage-way is to the continuous increase of hole distance, and the platform number of jet blower should constantly increase, when the 13rd transverse passage-way becomes unimpeded transverse passage-way, the platform number of jet blower will be increased to 7.

The wind supply quantity of portable blower SDF (A)-№ 6.5 is 11.17m ³/ s, wind tube outlet air quantity are 9.17m ³/ s is greater than the flat required airflow 8.93m of face institute that leads ³/ s.Therefore, portable blower SDF (A)-№ 6.5 can satisfy the demand.

The wind supply quantity of portable blower SDF (A)-№ 10 is 21.12m ³/ s, wind tube outlet air quantity are 18.71m ³/ s is greater than the positive required airflow 15.63m of hole face institute ³/ s.Therefore, portable blower SDF (A)-№ 10 can satisfy the demand.

Go into the hole air quantity all at 32m ³More than/the s, greater than 28.57m ³/ s should go into the hole air quantity.

According to above result of calculation, if the unimpeded transverse passage-way in import work area is 2870m to the ultimate range at this hole, work area, then its ventilation equipment (not containing standby) configuration is as follows:

1 of portable blower (SDF (A)-№ 6.5), institute's aid distributing pipe diameter phi is 1000mm;

1 of portable blower (SDF (A)-№ 10), institute's aid distributing pipe diameter phi is 1200mm;

Maximum 4 of jet blower (SSF-№ 12).

If the unimpeded transverse passage-way in outlet work area is to the ultimate range 5330m at this hole, work area.Then ventilation equipment (not containing standby) configuration is as follows:

1 of portable blower (SDF (A)-№ 6.5), institute's aid distributing pipe diameter phi is 1000mm;

1 of portable blower (SDF (A)-№ 10), institute's aid distributing pipe diameter phi is 1200mm;

Maximum 7 of jet blower (SSF-№ 12).

Implement part

Phase in is as follows:

When 1. just having begun to tunnel, positive hole peace is led, and adopts the pipeline forced ventilation respectively.A portable blower (SDF (A)-№ 6.5) is installed in outside the flat pilot tunnel, joins diameter phi 1000mm airduct and blows for the flat scope of operation of leading; A portable blower (SDF (A)-№ 10) is installed in outside the Zheng Dong hole, and joining diameter phi 1200mm airduct is the scope of operation air-supply of positive hole.

2. after first transverse passage-way connects, install SSF-№ 12 jet blowers in flat leading, the injection direction is inside, and portable blower (SDF (A)-№ 6.5) and portable blower (SDF (A)-№ 10) all move on in flat the leading, from the position of about 50 meters of transverse passage-ways, institute's aid distributing pipe is constant.φ 1000mm pipeline goes ahead and directly blows for the flat scope of operation of leading; φ 1200mm pipeline enters Zheng Dong through transverse passage-way, is forward the scope of operation air-supply of positive hole again.

3. after second transverse passage-way connects, SSF-№ 12 jet blowers install the position and the injection direction is constant, portable blower (SDF (A)-№ 6.5) and portable blower (SDF (A)-№ 10) move forward in flat leading, and from the position of about 50 meters of second transverse passage-ways, institute's aid distributing pipe is constant.φ 1000mm pipeline goes ahead and directly blows for the flat scope of operation of leading; φ 1200mm pipeline enters Zheng Dong through second transverse passage-way, is forward the scope of operation air-supply of positive hole again.Simultaneously, first transverse passage-way sealing.

4. after the 3rd transverse passage-way connects, SSF-№ 12 jet blowers install the position and the injection direction is constant, it is identical with first jet blower to increase a SSF-№ 12 jet blower injection directions again in flat the leading.Portable blower (SDF (A)-№ 6.5) and portable blower (SDF (A)-№ 10) move forward in flat leading, and from the position of about 50 meters of the 3rd transverse passage-ways, institute's aid distributing pipe is constant.φ 1000mm pipeline goes ahead and directly blows for the flat scope of operation of leading; φ 1200mm pipeline enters Zheng Dong through the 3rd transverse passage-way, is forward the scope of operation air-supply of positive hole again.Simultaneously, second transverse passage-way sealing.

5. the rest may be inferred, and after N transverse passage-way connected, 7-1 increased jet blower gradually according to table, and portable blower (SDF (A)-№ 6.5) and portable blower (SDF (A)-№ 10) progressively move forward in flat leading, from the position of about 50 meters of N transverse passage-ways.Institute's aid distributing pipe is constant.φ 1000mm pipeline goes ahead and directly blows for the flat scope of operation of leading; φ 1200mm pipeline enters Zheng Dong through N transverse passage-way, is forward the scope of operation air-supply of positive hole again.Simultaneously, N-1 transverse passage-way sealing.Finish up to tunnel excavation.

Claims (2)

1. tunnel construction jet flow laneway ventilation method is used for the constructing tunnel in parallel double hole; It is characterized in that: the pressurization of utilizing jet blower, in the parallel double hole, form main airstream, fresh air is entered from a hole and when flowing the nearly transverse passage-way that opens wide, utilize the pipeline forced ventilation fresh air of transverse passage-way upstream to be delivered to the work plane in two holes again; Foul atmosphere flows back to transverse passage-way from work plane, flows out from another hole again; Promptly first transverse passage-way perforation is dug the construction of finishing to whole parallel double is wide open between the parallel double hole, and its draft type is: in a hole jet blower is set therein, its drainage direction is inside; And two portable blowers are set in this hole and make them be positioned at the position of new perforation transverse passage-way rear portion 50-80, wherein a portable blower is the tunnel scope of operation air-supply at its place by pipeline; Another portable blower institute connecting leg road enters another hole through transverse passage-way, is its scope of operation air-supply more forward; Along with the perforation of new transverse passage-way, the transverse passage-way at its rear portion all seals.

2. tunnel construction jet flow laneway ventilation method according to claim 1, it is characterized in that: the design formulas that matches with described method of ventilation, in order to calculate hole air quantity, portable blower wind supply quantity, wind tube outlet air quantity and jet blower platform number, its design formulas is:

$\left\{\begin{array}{c}(R_{a1}+R_{b1}+R_h){Q_{\mathrm{ga}}}^2+(R_{a1}+R_{b1}){Q_{\mathrm{gb}}}^2+(R_{a1}+R_{b1}+R_{a2}+R_h){Q_{a2}}^2\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{\mathrm{gb}}+2\&CenterDot;(R_{a1}+R_{b1}+R_h)Q_{\mathrm{ga}}{Q}_{a2}\\ +2\&CenterDot;(R_{a1}+R_{b1})Q_{\mathrm{ga}}{Q}_{a2}-a_L(Q_{\mathrm{ga}}+Q_{\mathrm{gb}}+Q_{a2})-a_2=0\\ -F_1\left(Q_{\mathrm{ga}}\right)+(R_{\mathrm{ga}}+R_{a3}){Q_{\mathrm{ga}}}^2-R_{a2}{Q_{a2}}^2=0\\ -F_2\left(Q_{\mathrm{gb}}\right)-R_h{Q_{\mathrm{ga}}}^2+(R_{\mathrm{gb}}+R_{b2}){Q_{\mathrm{gb}}}^2-(R_h+R_{a2}){Q_{a2}}^2-2\&CenterDot;R_h{Q}_{\mathrm{ga}}{Q}_{a2}=0\end{array}\right.---\left(1\right)$

In the formula

R _A1---a hole from the hole to the windage of portable blower place section, kg.s ²/ m ⁸

R _A2---the windage of a hole from portable blower to unimpeded transverse passage-way, kg.s ²/ m ⁸

R _A3---the windage of a hole from unimpeded transverse passage-way to work plane, kg.s ²/ m ⁸

R _B1---the b hole from the hole to the windage of unimpeded transverse passage-way, kg.s ²/ m ⁸

R _B2---the windage of b hole from unimpeded transverse passage-way to work plane, kg.s ²/ m ⁸

R _Ga---be the windage of a hole scope of operation air-supply pipeline, kg.s ²/ m ⁸

R _Gb---be the windage of b hole scope of operation air-supply pipeline length, kg.s ²/ m ⁸

R _h---the windage of unimpeded transverse passage-way, kg.s ²/ m ⁸

Q _A1---the air quantity in from the hole to section a hole, portable blower place, m ³/ s;

Q _A2-air quantity in from portable blower to unimpeded transverse passage-way a hole, m ³/ s;

Q _Ga---be the air quantity in a hole scope of operation air-supply pipeline, m ³/ s;

Q _Gb---be the air quantity in a hole scope of operation air-supply pipeline, m ³/ s;

Q _h---the air quantity in the unimpeded transverse passage-way, m ³/ s;

F ₁(Q _Ga)---portable blower a characteristic curve function;

F ₂(Q _Gb)---portable blower b characteristic curve function.

Images