46results about How to "Excavation face stability" patented technology

The invention relates to a muddy water balance push bench. The muddy water balance push bench comprises a steel cylindrical housing, a cutting blade disc arranged at the front end of the steel cylindrical housing as well as a cutting disc driving unit, a hinged unit, an electrical instrument control unit and a mud conveying and circulating unit which are accommodated and supported in the steel cylindrical housing, wherein the cutting blade disc is used for cutting a soil body during excavation; the cutting disc driving unit is used for driving forward and reverse rotation of the cutting blade disc; the hinged unit is used for fitting an excavation curve, and especially suitable for the advance of a curve with the small radius; the electrical instrument control unit is used for controlling corresponding actions of all parts; the mud conveying and circulating unit is used for conveying mud and establishing balance of an excavation plane. The push bench provided by the invention adopts a muddy water balanced type, when the excavation plane in an unstable stratum is blocked, the muddy water can be used for pressurizing so as to enable the excavation plane to keep stable, and disturbance on the soil body around a jacked pipe is smaller, so that the land subsidence is smaller. The push bench can pass through transmission pipeline projects of roads, rivers, buildings and the like, and is simple to operate, high in speed and low in cost.

The invention provides a construction method for improving shield soil in a composite sand gravel stratum. Water, foam and bentonite slurry are used as composite improvement additives; and different additives are selectively injected to the front of a cutter head, the inside of a soil barn or a screw conveyor according to the actual working condition during shield driving with the aid of special improvement equipment and processes so as to play a role in improving the plastic fluidity of the soil, reducing the torque of the cutter head, stabilizing the excavation face and improving the driving efficiency.

The invention discloses a rational burying depth calculation method for constructing a subsea tunnel by a shield method. The method comprises the steps of determining meteorological, hydrological andgeological environment conditions of a to-be-constructed subsea tunnel region, and obtaining hydraulics parameter values and physical mechanics parameters of a rock-soil body; obtaining previous subsea tunnel cases, performing arrangement on construction information of single-hole/multi-hole tunnels with different geological conditions and diameters, and analyzing existent factors, influencing theburying depth, of the to-be-constructed subsea tunnel region; by an engineering analogy method and a numerical calculation method, determining different burying depth values under the influence of the factors; and by a weight analysis method, calculating out weight values of judgment factors to obtain a final burying depth value.

The invention discloses a method for realizing the balance of a shield excavated surface by regulating muddy water and air, comprising the following steps: a semi-clapboard is arranged in a muddy water bin to divide the muddy water bin into a front muddy water bin and a rear muddy water bin; the lower parts of the front muddy water bin and the rear muddy water bin are communicated; the muddy water is filled in the front muddy water, the compressed air is injected at the upper part of the rear muddy water; the muddy water height in the rear muddy water bin is monitored by a liquid level sensor; when fluctuating, the muddy water height is adjusted to a preset height by adjusting the rotation speed of a mud entering pump or a mud discharging pump; the pressure of the compressed air in the rear muddy water bin is monitored by an air pressure sensor while the muddy water height is fluctuated; and the pressure of the compressed air is kept at the preset value by adjusting an air inlet valve and an air exhaust valve, thus realizing the stability of the excavated surface in the process of the whole shield driving.

The invention provides a slurry shield model test mud cake thickness real-time measurement device which structurally comprises an air compressor, a valve A, a pressure regulating valve, a valve B, a sludge barrel, sludge, a valve C, a glass barrel, a valve D, a measuring cylinder, filtrate, an electronic balance, a computer, hoses and a valve E, wherein the air compressor is connected with the sludge barrel through the hoses, the valve A, the pressure regulating valve and the valve B, the sludge barrel is connected with the glass barrel through the hoses and the valve C, the glass barrel is connected with the measuring cylinder containing the filtrate through the hoses and the valve D, the measuring cylinder is placed on the electronic balance, the electronic balance is connected with the computer through a serial data cable, the valve E is connected with the glass barrel, and the sludge is placed in the sludge barrel. A real-time measurement method includes the steps: (1) preparing the sludge, a stratum layer and a filter layer; (2) measuring the thickness of a mud cake in real time. The device has the advantage that the thickness of the mud cake can be measured by probe pressure in real time conveniently and accurately.

Disclosed is a large-span subway station underground excavation construction method for a hard rock stratum. The large-span subway station underground excavation construction method for the hard rock stratum is used for effectively reducing the excavation construction risk and improving the excavation construction efficiency. The large-span subway station underground excavation construction method for the hard rock stratum comprises the following steps that the arch portion middle of a station is divided into two steps to be excavated, a tunnel arch portion middle upper step is excavated, and an initial support arch cover of the tunnel arch portion middle is constructed; a tunnel arch portion middle lower step is excavated; a tunnel arch portion left side portion and a tunnel arch portion right side portion are excavated, feet-lock bolts are constructed at the arch foot positions, the initial support arch cover on the arch top is lengthened through connection, and construction of the initial support arch cover is accomplished; a rock mass arranged below the station is excavated in a slot broaching mode under the protection action of the initial support arch cover, nine portions including upper steps on the left portion, the middle portion and the right portion, middle steps on the left portion, the middle portion and the right portion and lower steps on the left portion, the middle portion and the right portion are excavated, and side wall initial supports of corresponding sections are constructed until the rock mass is excavated to the bottom; and a station body structure is sequentially constructed from bottom to top, and station construction is accomplished.

The invention discloses a construction method for reducing the disturbance of a slurry shield passing through a foundation-free residential area. The construction method comprises the steps of performing house detection and evaluation; performing ground tracking grouting reinforcement on the seriously damaged house; doing pre-traversing preparation work; setting various parameters in the traversing process; and performing in-tunnel grouting reinforcement; and performing monitoring measurement control. According to the construction method, disturbance to a building when the slurry shield passesthrough the foundation-free residential area is reduced, normal construction of the slurry shield is guaranteed, facility safety of the foundation-free residential area is guaranteed, and the construction method has wide guiding significance for construction in the field.

The invention provides a foaming agent specially used for a soil pressure balance shield tunneling machine and a preparation method thereof, and relates to the field of shield construction buildings. The foaming agent is prepared from the following raw materials, in parts by weight: 6-10 parts of sodium dodecyl sulfate, 9-15 parts of dodecyl betaine, 3-5 parts of sodium chloride, 6-8 parts of n-butyl alcohol, 4-6 parts of dodecyl dimethyl amine oxide, 2-3 parts of sodium lauryl alcohol polyoxyethylene ether sulfate, 5-7 parts of sodium alginate, 3-7 parts of sodium dodecyl polyoxyethylene ether sulfate, 3-5 parts of hexadecyl trimethyl ammonium chloride, 2-3 parts of fluoranthene, 2-4 parts of ethylenediamine tetraacetic acid disodium salt, 3-5 parts of a cinnamon bark extractive, 3-5 parts of polyethylene glycol, 5-7 parts of a tackifier, and 70-100 parts of water, and the preparation method comprises three steps. According to the invention, the foaming agent can improve soil plasticity, fluidity and impermeability, can improve residual soil fluidity in seal earth cabins, protects cutting tools, reduces cutter head torque, can make soil bodies formed soil plugs in a screw conveyer, and effectively prevents spewing, and the foaming agent has no toxicity, no corrosion, good bubble stability, and long duration time.

This is a preparing method of PMS mud and water paste and its application on the working of supporting pipe. Its features are: Use high polymer and positron glue to prepare PMS mud and water paste liquid. During this procession, to use soil mortar liquid separated grade by grade, in the mud paste mix PMS paste liquid and its assistant materials in proper time, and advance the six steps on the application.

The invention relates to the field of highway tunnel and railway tunnel surrounding rock supporting, in particular to a large cross-section tunnel supporting system construction method applicable to steep dip layered rock mass. The method is characterized in that when a forward inclination layer pilot tunnel and an upper part middle pilot tunnel are dug, a temporary support and first and second layer linings positioned in the positions of the forward inclination layer pilot tunnel and the upper part middle pilot tunnel are made; and when a backward inclination layer pilot tunnel and a lower part pilot tunnel are dug, a temporary support and a first layer lining positioned at the backward inclination layer pilot tunnel and the lower part pilot tunnel are made. The method has the advantages that by aiming at the steep dip layered rock mass tunnel digging damage features, the strength and the rigidity of top and arch part supporting structures are mainly reinforced; the strength and deformation characteristics of surrounding rock of tunnel top and layer exposure parts can be effectively enhanced; the deformation and the instability of the surrounding rock in the two weak positions are controlled; and the stability of the rock mass in the arch part or layer exposure parts is ensured.

The invention relates to the technical field of mechanical control of building construction and mainly discloses an automatic control device and an automatic control method for the head-earth pressure in mechanical tube jacking construction. The automatic control device comprises a tube jacking machine, a front shell, hydraulic oil cylinders, a rear shell, a sealing device, a jacking-in tube section, an overflow valve, a hydraulic pump station, a hydraulic pipeline and a hydraulic oil loop, and is characterized in that the tube jacking machine is arranged at the front end of jacking-in direction in the mechanical jacking, the front shell and the rear shell are arranged at the rear part of the tube jacking machine, and are connected by a plurality of hydraulic oil cylinders, sealing devices are arranged outside the hydraulic oil cylinders, the plurality of hydraulic oil cylinders are respectively connected in parallel by the hydraulic pipeline and are respectively connected with the hydraulic pump station, and the hydraulic pump station is provided with the hydraulic oil loop which is provided with the overflow valve. The automatic control device disclosed by the invention can respond to the head-on earth pressure of the tube jacking machine in real time, then the control device automatically adjusts the jacking force of a head of the tube jacking machine, the control oil supply can be realized by the adjustable overflow valve on an oil path, so that the tube jacking machine can respond to the pressure of the head-on earth pressure in real time, the effect of earth pressure balance is realized, and the method is simple and effective.

The invention discloses a combined framework steel structure of a jacked subway bridge. The combined framework steel structure comprises a square main frame structure and sub frame structures, wherein the main frame structure consists of vertical oblong frameworks, a longitudinal upper supporting beam at the top, a transverse top cross beam, a spacing beam, a longitudinal lower supporting beam at the bottom and a transverse bottom cross beam, which are fixedly connected into a whole through bolts; and the sub frame structures are positioned at the upper part of the front end of the main frame structure. The method for tunneling a subway bridge comprises the following steps: jacking the sub frame structures at intervals to reduce resistance during jacking and disturbance to the soil, and jacking the square main frame structure; digging soil under the support and shield of the sub frame structures and the main frame structure, and delivering out the soil of a dug surface; and repeatedly and circularly jacking till the reinforced concrete subway bridge is jacked to a designed position, and detaching the combined framework steel structure at the front end. The combined framework steel structure can be assembled for jacking the subway bridges or culverts of different sections, and can greatly save steels and construction cost by repeated use; and the method can ensure soil holding pressure balance, stable excavating surface and safe operation, reduce speed limit of lines and reduce the influence on transportation.

The invention discloses a SCAP type cabin opening method with pressure based on an earth pressure balance shield machine. Grain composition of a stratum where the shield machine is located is collected, and a suitable mud material is selected. A gap between the shield machine and the stratum where the shield machine is located, and pores of a soil body of an excavation surface are injected with mud to be blocked, and the soil body around the shield machine is reinforced; a part of muck in a soil cabin is discharged, mud is injected into the soil cabin, and the excavation surface is kept stable; then a cutter disc is retracted, seepage pressure of the mud in the soil cabin is improved to conduct mud seepage, and an integral air tight mud film is formed on the excavation surface; and finally, the muck and the mud are discharged to prepare cabin opening operation. The mud film is effectively formed, stability and the airtight property of the excavation surface are ensured, the problems ofdifficulty of cabin opening with the pressure in a high-permeable stratum, and poor air tightness are solved, and preparation time of the cabin opening operation with the pressureis saved. Accordingto the SCAP type cabin opening method, the technological process of mud film formation is easy and simple to do, other equipment does not need to be added, andthe simple and practicable, quicker and more economic method of earth pressure shield cabin opening with the pressure is provided.

The invention discloses a large-size rectangular pipe jacking construction method for an upper-soft lower-hard stratum, and belongs to the technical field of pipe jacking construction. The large-size rectangular pipe jacking construction method for the upper-soft lower-hard stratum comprises the following steps that S01, hard rock pretreatment is conducted, specifically, hard rock invading a pipe jacking tunnel is subjected to pre-crushing treatment; S02, the excavation diameter is enlarged, specifically, a cutter head is adjusted, and the excavation diameter of the bottom of a pipe jacking machine is enlarged; S03, pressure injection of slurry and a thickening agent is conducted, specifically, the slurry and the thickening agent are pressure-injected in front of the cutter head, so that the workability of a soil body is improved, the pressure of the soil body is balanced, and the excavation surface of a sand layer is kept stable; S04, anti-sedimentation treatment is conducted, specifically, high-consistency bentonite is injected into the periphery of the duct piece for filling; and S05, posture adjustment is conducted, in the jacking process, axis deviation correction and posture roll correction are conducted on the pipe jacking machine, and jacking accuracy is guaranteed. The technical problems that in upper-soft lower-hard complex geological large-size rectangular pipe jacking construction, the pipe jacking machine floats upwards and rolls left and right are effectively solved.

The invention relates to a device and method for improving the supporting effect of an excavation face of an earth pressure balance type tunnel boring machine. The device comprises an exhaust system, a grouting system and an industrial personal computer; the method comprises the following steps that during a shutdown period of a shield tunneling machine, gas pressure P1 in a soil bin is measured through a pressure sensor, meanwhile, the industrial personal computer obtains underground water pressure P2 at the same height, and if P1 is larger than or equal to P2, exhaust and grouting operation does not need to be conducted; if P1 is smaller than P2, the exhaust system is controlled by the industrial personal computer to exhaust gas until gas in the soil bin is completely exhausted; after exhaust is stopped, the grouting system is started through the industrial personal computer, the grouting pressure is set to be P2, the change of the monitored value P1 is observed during grouting, and when the monitored value P1 of the pressure sensor is equal to P2, the grouting system is closed; and after shutdown, P1 and P2 are compared once every 1 h, and when P1 is smaller than P2, the steps S2-S3 are repeated. According to the device and the method, the exhaust system and the grouting system are additionally arranged, operation is convenient, and the construction quality and safety can be effectively improved.