The invention discloses a muck improvement technology for earth pressure balance shield construction in a sandy cobble stratum and relates to the technical field of stratum shield construction. The improvement technology comprises the following steps: 1, selection of a land improver; 2, land improvement; 3, construction quality control; 4, a soil mass improvement effect and analysis. The improvement technology is simple, and after improvement, muck can be prevented from forming mud cakes on a cutter head, being accumulated in an earth bin, blocking the bin and causing blocking, spewing, wear of the cutter head and a tool and the like at a screw conveyor.

Muck improvement technology for earth pressure balance shield construction in sandy cobble stratum

PURPOSE:To improve the permeability to a facing by using a silicic acid type paste obtained by crushing a silicic acid type water jelly having a specific wt.% of including rate of silicon dioxide, and bubbles or a foaming agent, as a pouring material of a shield excavation method. CONSTITUTION:A shield type excavator 1 under the ground, and a pouring material feeding plant 2 on the ground are connected to a pouring line 3 through a compression pump 4, and a feeding port 8 of the pouring material is provided on the face plate 7 having the facing cutter 6 of the shield type excavator 1. Then, an earth pressure chamber 9 is provided at the near side of the facing cutter 7, a ribbon screw 10 is provided linking to the earth pressure chamber 9, a sand plug zone 12 is formed at the rear side, and the excavation muck mixed with the pouring material is filled in the earth pressure chamber 9. Then, minute particles produced by crushing a silicic acid type water jelly having about 1 to 60wt.% of including rate of silicon dioxide; a silicic acid type paste mainly of a liquid having a liquidity provided among the minute particles; and bubbles or a foaming agent; are used as a pouring material. And such a pouring material is delivered and poured to the facing through the pouring line 3.

Shield excavation method by using bubble and jelly

The present invention relates to a slurry shield tunnel boring machine (TBM) which uses slurry introduced into a slurry treating plant by generating fine air bubbles such as micro or nano air bubbles in the slurry and transferring the slurry to a digging surface, and a tunneling method using the same. For this, a slurry shield TBM which includes a cutting head digging a digging surface by rotating and moving forward while directly coming into contact with the digging surface and into which muck which is excavated soil is inserted; a chamber charged into the slurry and mixed with the slurry; a main TBM body moving forward in a predetermined distance by a propelling means and digging the soil; a slurry tank connected to the chamber to supply slurry to the chamber; a slurry treating plant connected to the chamber to discharge slurry mixed with the muck in the chamber; and a slurry circulation system configured to enable the slurry charged into the chamber to maintain predetermined slurry pressure, wherein the slurry tank or the slurry treating plant generates micro or nano air bubbles in the slurry, such that slurry, in which micro or nano air bubbles are generated, is used to decrease a permeability coefficient of soil in a digging step to increase an inner friction angle of the soil, thereby decreasing required slurry pressure.

Slurry shield tbm using micro air bubble and the tunnel construction method thereof

The invention discloses a micro disturbance construction method for overlapped shield tunnels to pass through an operation subway tunnel. The method comprises the following steps that A, a water falltest and a recharging test are conducted on the construction section, and test data are obtained; B, according to the test data, underground water of the construction section is lowered to be below the bottoms of the overlapped shield tunnels by 1m or below; C, shield construction is conducted on the overlapped shield tunnels, and synchronous grouting is conducted on the overlapped shield tunnels;D, secondary grouting is conducted on gaps between overlapped shield tunnel synchronous grouting layers and a stratum; and E, grouting strengthening is conducted on a soil clamping body between the two overlapped shield tunnels. Through usage of the method, disturbance on the stratum during overlapped shield tunnel construction can be reduced.

Micro disturbance construction method for overlapped shield tunnels to pass through operation subway tunnel

The invention discloses a construction method for a shield machine passing through an air shaft. The work of hoisting in an early stage and dismantling in a later stage of a conventional bracket is eliminated, the construction period is shortened, the construction cost is reduced, half-ring pipe segments are assembled between two sections of integral ring pipe segments, and the number of two sections of the integral ring pipe segments and the number of the intermediate half-ring pipe segments are determined according to the specific size of the intermediate air shaft. Continuous assembly of the half-ring pipe segments can meet the stress requirements, costs are effectively saved, the construction progress is speeded up, and installation and disassembly in the later stage are facilitated. The two ends of each support member are separately supported between the two sections of the integral ring pipe segments, and are beneficial to ensuring the continuity and stability of the force transmission, the risk of tunneling of the shield machine is reduced, strong guarantee is provided for secondary originating of the shield machine after the shield machine passes through the air shaft, meanwhile, subsequent dismantling work is facilitated, the construction method is widely used in intermediate air shafts of various sizes and especially suitable for large-sized intermediate air shafts such as the air shafts with the length being 30-50m, and the shield machine can pass through the air shaft quickly and safely.

Construction method for shield machine passing through air shaft

PURPOSE:To provide an improvement in mud pressure shield method. CONSTITUTION:A shield excavator having a rotating face cutter part, a soil pressure chamber, a stirring mechanism for stirring the soil in the soil pressure chamber, a mechanism for discharging the soil in the soil pressure chamber, and a filling material guide pipe for injecting a filling material into a face is operated, and a soil layer is excavated while injecting the filling material into the face surface or the soil pressure chamber. As the filling material, a siliceous aqueous jelly is used. The improvement in soil value in respect to flowability and water stopping property can be performed without accelerating the separation from the excavated earth and sand. Thus, problems such as stop of shield excavation and face breakage can be solved. Further, the mixed excavation muck discharged in this way can be treated as a general earth as it is dried while leaving as it is and the water content ratio is reduced below a half.

Shield excavating method

PURPOSE:To maintain a stable excavation by using minute particles produced by crushing a silicic acid type jelly, and a silicic acid type paste mainly of a liquid having a liquidity as a whole, being provided among the above minute particles, as a pouring material. CONSTITUTION:A pouring material is compressed from a silicic acid type paste feeding plant 2 to a feeding port 8 provided on the face plate of a shield type excavator 1 by a compression pump 4, and the excavation muck cut from a facing and mixed with the pouring material is exhausted from an earth pressure chamber 9 through a conveyer 22. Then, minute particles produced by crushing a silicic acid type water jelly having about 1 to 60wt.% of inclusion rate of silicon dioxide, and a silicic acid type paste mainly of a liquid having a fluidity as a whole being provided among the above minute particles, are used as a pouring material. And the paste has a fluidity in the condition of a sol suspension, and it reduces the passing resistance so as to feed the pouring material stably to the facing. By this fluidity, the paste is permeated to the facing regardless of the existence of cobble stones and the like, the water stop property is improved, and a stable excavation is maintained.

Tsuruoka Tsuguhide

Papers

Shield excavation method by using bubble and jelly

Shield excavating method

Shield excavation method