CN108708732A - A kind of mud stone compound stratum slurry shield cutterhead, shield machine, speedy drivage method - Google Patents

Abstract

The invention relates to a slurry mud-water shield cutter head in a mudstone composite stratum, a shield machine and a rapid excavation method. The auxiliary radial arm is welded by multiple wear-resistant composite steel plates. There is a gap structure between two adjacent wear-resistant composite steel plates, and an open-hole welding structure is provided in the middle of each wear-resistant composite steel plate. The invention can reduce the problem of wear and tear of the cutter head during use, and the shield machine provided can increase the speed of excavation and increase the efficiency of tunnel excavation.

Description

Mud-water shield cutter head, shield machine and rapid excavation method in mudstone composite stratum

technical field

The invention belongs to the field of shield technology, and relates to a mud-water shield cutter head, a shield machine and a rapid tunneling method in a mudstone composite stratum.

Background technique

A shield machine is a tunnel boring machine that uses the shield method. The construction method of the shield machine is the "shield" (referring to the supporting segment) of the tunnel constructed (laid) by the roadheader while driving. It is different from the open construction method. In my country, it is customarily used for tunneling in soft soil strata. The machine is called (narrow sense) shield machine, and the one used for rock formation is called (narrow sense) TBM. Tunnel construction with shield machine has the advantages of high degree of automation, saving manpower, fast construction speed, one-time hole formation, no climate influence, control of ground subsidence during excavation, reduced impact on ground buildings and underwater excavation. It does not affect ground traffic during excavation, and it is more economical and reasonable to use a shield machine for construction when the tunnel line is long and the buried depth is large.

The basic working principle of the shield machine is that a cylindrical steel component is pushed forward along the tunnel axis to excavate the soil. The shell of the cylindrical assembly is the shield, which acts as a temporary support for the excavated, unlined tunnel section, withstands the pressure of the surrounding soil and sometimes groundwater pressure and keeps it out. Excavation, soil dumping, lining and other operations are carried out under the cover of the shield.

During the construction of the shield tunneling through the round gravel and mudstone soil layers, the mud water treatment system cannot meet the needs, and the sedimentation tank of the mud circulation system cannot adjust the slurry index, and the particles are too fine to settle. After particle screening, it is found that the suspended solids in the mud are mostly ultrafine particles of about 0.020mm or smaller, resulting in a serious imbalance in mud performance indicators, the proportion of incoming slurry will become large, and the viscosity will also increase. The shield excavation excavation dregs are suspended and flowed, resulting in the inability to meet the construction and excavation, and in severe cases, excessive subsidence of the ground surface; and the torque of the cutter head is small, the thrust is large, the excavation speed is small, and even the excavation does not move, which has shown that the excavation A large number of mud cakes have begun to form in the cabin, and the construction risk is huge.

With the continuous development of the shield machine, the requirements for the shield machine are getting higher and higher. During the excavation process of the full-section mudstone formation, the cutter head is easily worn, which affects the life of the shield machine. In addition, the clay blocks cut by the shield machine will accumulate in the excavation chamber of the shield machine, stick to the surface of the cutter head, and form a mud cake, resulting in a decrease in the cutting ability of the shield machine, and even the inability to continue the excavation construction, affecting the processing progress continue.

Contents of the invention

In view of this, the object of the present invention is to provide a mudstone composite formation mud-water shield cutter head, which can reduce the wear and tear problem of the cutter head during use, and the shield machine provided can increase the speed of excavation and increase the efficiency of tunnel excavation .

To achieve the above object, the present invention provides the following technical solutions:

A mud-water shield cutter head in a mudstone composite formation, the cutter head adopts a radial plate structure, including a cutter head frame, a tool assembly arranged on the cutter head frame, a plurality of main spoke arms and auxiliary spoke arms, and each auxiliary spoke arm is composed of A plurality of wear-resistant composite steel plates are combined and welded. A gap structure for welding is provided between two adjacent wear-resistant composite steel plates. A square hole is provided in the middle of each wear-resistant composite steel plate. It is a square welded with wear-resistant composite steel plate in the opening.

Further, the height of the wear-resistant welding seam is 4mm.

Further, a reinforcing ring rib is provided between the main spoke arm and the auxiliary spoke arm.

Further, it also includes a wear detection device for detecting the wear condition of the wear-resistant composite steel plate.

Further, a gauge knife is arranged on the edge of the cutter head, and the height of the gauge knife on the edge of the cutter head is 15 mm, and the width is 150 mm.

A shield machine includes the above-mentioned cutter head, and also includes a muddy water treatment system and a muddy water flushing system.

A rapid excavation method of a shield machine, the pressure of the excavation chamber is 0.115 bar per buried depth of 1m, the pressure of the air cushion chamber is 0.3 bar higher than the pressure of the excavation chamber, the speed of the cutter head is 0.8-1.0r/min, and the thrust of the excavation The excavation speed is 1000-1300T, the excavation speed is 25-40mm/min, the grouting volume is 4.7-5.5m ³ , the grouting pressure is 3-3.5bar, the mud feeding volume is 850-900m ³ /h, and the mud discharge volume is 900- 950m ³ /h.

Further, the muddy water treatment system uses filter press equipment to process the waste slurry, presses the waste slurry into a mud cake, and prepares fresh mud with the filtered liquid.

Further, the muddy water flushing system adopts a high-pressure flushing method to flush the front of the slag outlet grille, the back of the cutter head and the cutter assembly.

The beneficial effects of the present invention are:

It can reduce the problem of wear and tear during the use of the cutter head. The shield machine provided can effectively reduce the probability of mud cake formation in the center, increase the speed of excavation, increase the efficiency of tunnel excavation, and ensure that the shield machine can operate in the upper soft and lower hard strata. Normal digging.

Description of drawings

In order to make the purpose, technical scheme and beneficial effect of the present invention clearer, the present invention provides the following drawings for illustration:

Fig. 1 is the structural representation of cutterhead of the present invention;

Fig. 2 is a schematic diagram of the structure along A-A in Fig. 1 .

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

A slurry shield cutter head for mudstone composite formation, the cutter head adopts a radial plate structure, including a cutter head frame 1, a cutter assembly 2 arranged on the cutter head frame, several main radial arms 3 and auxiliary radial arms 4, each The auxiliary radial arm 4 is welded together by a plurality of wear-resistant composite steel plates, a gap structure is provided between two adjacent wear-resistant composite steel plates, and a square opening 5 is provided in the middle of each wear-resistant composite steel plate, and a set A block welded as a whole with the wear-resistant composite steel plate in the opening.

In this embodiment, a wear-resistant welding seam is additionally provided at the welding seam between two adjacent wear-resistant composite steel plates. The height of the wear-resistant weld is 4mm. A reinforcing ring rib 6 is provided between the main spoke arm 3 and the auxiliary spoke arm 4 . This embodiment also includes a wear detection device 7 for detecting the wear of the wear-resistant composite steel plate. A gauge knife is arranged on the edge of the cutterhead, and the height of the gauge knife on the edge of the cutterhead is 15mm and the width is 150mm. Since the round gravel formation cannot change the cutter, setting the gage cutter can protect the cutter head very well.

A shield machine includes the above-mentioned cutter head, and also includes a muddy water treatment system and a muddy water flushing system.

A rapid excavation method of a shield machine, which adopts the above-mentioned cutter head, and the specific excavation process adopts the method of the prior art. In this method, the pressure of the excavation chamber 8 is 0.115 bar per buried depth of 1m, and the pressure ratio of the air cushion chamber 9 is 0.115bar. The pressure of bin 8 is 0.3 bar higher, of which 10 is a buried wall door arranged between excavation bin 8 and air cushion bin 9, the speed of the cutter head is 0.8-1.0r/min, the thrust of excavation is 1000-1300T, and the excavation speed The grouting volume is 25-40mm/min, the grouting volume is 4.7-5.5m ³ , the grouting pressure is 3-3.5bar, the mud entry volume is 850-900m ³ /h, and the mud discharge volume is 900-950m ³ /h.

The muddy water treatment system uses filter press equipment to process the waste slurry, presses the waste slurry into a mud cake, and prepares fresh mud with the filtered liquid. The muddy water flushing system adopts a high-pressure flushing method to flush the front of the slag outlet grid, the back of the cutter head and the cutter assembly, which improves the phenomenon of clogging of the slag outlet and mud cake formation on the cutter head.

In this embodiment, an APN type filter press equipment and admixture adding equipment are selected to process the waste slurry, and the mud performance index is adjusted from passive to active. The waste slurry treatment through the filter press equipment meets the adjustment of the slurry formation index under the existing conditions, and achieves the "3R" principle, that is, reduce raw materials (reduce), reuse (reuse) and recycle (recycle). The waste slurry is pressed into a mud cake by the filter press equipment, and the filtered water will be prepared with fresh mud. At the same time, the pressing of the mud cake can also be used for station roof backfilling and other operations, while reducing construction costs.

The amount of synchronous grouting is adjusted to 4.7-5.5m ³ considering the diffusion coefficient of the slurry. The amount of overbreak of the mud-water shield is small, and the mud film produced by the mud can inhibit the diffusion of the slurry. Therefore, the grouting pressure should be slightly greater than the excavation chamber pressure, controlled between 3-3.5bar (to prevent insufficient synchronous grouting if the pressure is too low, and the grout may leak from the tail of the shield if the pressure is too high). The distribution of synchronous grouting amount is the key point of control during the downrunning period. Increase the upper grouting in the straight section to suppress the floating of the segment, and increase the grouting in the upper and outside of the curve to suppress the floating and lateral deviation of the segment. Excessive slurry discharge will result in part of the slurry not being screened and directly entering the slurry storage tank, resulting in an increase in the specific gravity of the slurry and affecting normal construction; therefore, in this embodiment, the mud intake is controlled at 850-900m ³ /h, and the mud discharge is controlled at 900-950m ³ /h.

Applying the device of this embodiment to a specific engineering application has achieved beneficial effects.

1) The control of surface settlement is better, and compared with the earth pressure shield machine, the advantage is very obvious. The average surface settlement is only about 3mm, while the surface settlement of adjacent sections using earth pressure shield machines has exceeded 30mm.

2) The tunneling speed is ideal. The average monthly progress reaches 270m/month.

3) Better protection for knives. According to the experience of the whole line, the earth pressure shield machine needs to replace the tool once in the round gravel formation on average 300-500m. However, the muddy water shield machine in this bidding section has excavated 1468m at a time, and the cutters have not been replaced, and 85% of the shield machine cutters can continue to be used after penetration.

Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that it can be described in terms of form and Various changes may be made in the details without departing from the scope of the invention defined by the claims.

Claims (10)

1. a kind of mud stone compound stratum slurry shield cutterhead, the cutterhead uses plate spoke structure, including cutterhead frame, setting in knife Toolbox, several main spoke arms on plate rail and secondary spoke arm, it is characterised in that：Every secondary spoke arm is by polylith wear-resistant composite steel board group Conjunction is welded, and the gap structure for welding is equipped between adjacent two pieces of Wear-Resistant Compound Steel Plates, every piece of Wear-Resistant Compound Steel Plate Centre is equipped with square opening, further includes the square that setting is welded as a whole with Wear-Resistant Compound Steel Plate in the opening.

2. mud stone compound stratum slurry shield cutterhead according to claim 1, it is characterised in that：Adjacent two pieces wear-resisting compound Commissure between steel plate also has additional wear-resisting weld seam.

3. mud stone compound stratum slurry shield cutterhead according to claim 2, it is characterised in that：The height of the wear-resisting weld seam Degree is 4mm.

4. mud stone compound stratum slurry shield cutterhead according to claim 1, it is characterised in that：The main spoke arm and secondary spoke Enhancing steel ring is equipped between arm.

5. mud stone compound stratum slurry shield cutterhead according to claim 1, it is characterised in that：Further include for detecting State the wear detector of Wear-Resistant Compound Steel Plate abrasion condition.

6. mud stone compound stratum slurry shield cutterhead according to claim 1, it is characterised in that：Gauge is arranged in cutterhead edge Knife.

7. mud stone compound stratum slurry shield cutterhead according to claim 6, it is characterised in that：The gauge knife up degree is 15mm, width 150mm, quantity are 4.

8. a kind of shield machine, it is characterised in that：Further include Slurry treatment including such as claim 1-7 any one of them cutterhead System and muddy water flushing system, it is 0.115bar to excavate storehouse pressure per buried depth 1m, and it is high that air cushion storehouse pressure ratio excavates storehouse pressure The rotating speed of 0.3bar, the cutterhead are 0.8-1.0r/min, and driving thrust is 1000-1300T, and driving speed is 25~40mm/ Min, grouting amount 4.7-5.5m³, grouting pressure 3-3.5bar, inputiing mud volume is 850-900m³/ h, sludge volume are 900- 950m³/h。

9. a kind of speedy drivage method of shield machine, it is characterised in that：The Slurry treatment system is using at filtering equipment Useless slurry is managed, useless slurry is pressed into mud cake, the clear water filtered out carries out the modulation of fresh mud.

10. speedy drivage method according to claim 9, it is characterised in that：The muddy water flushing system is rushed using high pressure Brush mode washes away slag-drip opening grid front, the cutterhead back side and toolbox.