CN114991165A - Construction method for subway deep foundation pit adjacent to railway business line - Google Patents
Construction method for subway deep foundation pit adjacent to railway business line Download PDFInfo
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- E02D17/00—Excavations; Bordering of excavations; Making embankments
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- E02D17/04—Bordering surfacing or stiffening the sides of foundation pits
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- E02D15/00—Handling building or like materials for hydraulic engineering or foundations
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- E02D15/04—Placing concrete in mould-pipes, pile tubes, bore-holes or narrow shafts
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- E02D15/08—Sinking workpieces into water or soil inasmuch as not provided for elsewhere
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- E—FIXED CONSTRUCTIONS
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- E02D19/12—Restraining of underground water by damming or interrupting the passage of underground water
- E02D19/18—Restraining of underground water by damming or interrupting the passage of underground water by making use of sealing aprons, e.g. diaphragms made from bituminous or clay material
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- E02D29/045—Underground structures, e.g. tunnels or galleries, built in the open air or by methods involving disturbance of the ground surface all along the location line; Methods of making them
- E02D29/05—Underground structures, e.g. tunnels or galleries, built in the open air or by methods involving disturbance of the ground surface all along the location line; Methods of making them at least part of the cross-section being constructed in an open excavation or from the ground surface, e.g. assembled in a trench
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Abstract
The invention provides a construction method of a subway deep foundation pit adjacent to a railway business line, which comprises the following steps: step 1, constructing a foundation pit supporting structure; the main supporting structure of the foundation pit is mainly a secant pile combined with an inner support to support the foundation pit and also serve as a waterproof curtain; step 2, carrying out excavation construction on foundation pit earthwork, wherein the foundation pit is excavated in a longitudinal segmentation and vertical layering mode, is supported by a groove, is supported and then excavated, and is excavated along with the support; step 3, constructing a main body structure of the subway station, wherein the main body structure of the subway station is constructed by an open cut method, and is constructed in a longitudinal segmentation, vertical layering and bottom-to-top mode; and 4, backfilling earthwork after the main body structure of the subway station reaches the design strength, and backfilling the foundation pit symmetrically in layers. The construction method has the advantages that the influence of the construction of the foundation pit of the subway station on the adjacent railway line is small, the construction efficiency is high, and the effect of containing the adjacent railway line is achieved.
Description
Technical Field
The invention belongs to the technical field of foundation pit construction, and particularly relates to a construction method of a subway deep foundation pit adjacent to a railway business line.
Background
In recent years, with the increasing development of urban underground space projects, foundation pit projects have a development trend of large scale, irregularity and high complexity, and how to safely, economically and efficiently develop underground space in cities with dense building structures becomes one of the subjects of key research. In each stage of foundation pit engineering design, the foundation pit excavation generates certain disturbance to adjacent building structures, such as city main roads, city viaducts, railways, buildings and the like, and great design and construction risks are caused; particularly, when large-scale deep foundation pit excavation is performed in an area adjacent to a railway line, the existing deep foundation pit excavation construction method has a large influence on an adjacent railway line, and the effect of protecting the adjacent railway line is difficult to achieve.
Therefore, there is a need to provide an improved solution to the above-mentioned deficiencies of the prior art.
Disclosure of Invention
The invention aims to provide a construction method for a subway deep foundation pit adjacent to a railway business line, which at least solves the problems that the existing construction method has great influence on the adjacent railway line and the like.
In order to achieve the above purpose, the invention provides the following technical scheme:
a construction method for a subway deep foundation pit adjacent to a railway business line comprises the following steps:
and 4, backfilling earthwork after the main body structure of the subway station reaches the design strength, and backfilling the foundation pit symmetrically in layers.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, the geometric state of the railway track is measured before the foundation pit is constructed, and the deformation of the railway business line and the deformation of the foundation pit are monitored in real time in the construction process;
and when the monitored deformation reaches the pre-inspection alarm value, performing construction treatment in time.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, when the bored pile is constructed, the long pile casing penetrates through a poor stratum to be embedded into a stable stratum at a section with poor geological conditions, drilling is performed to form a hole according to a rotary drilling mud retaining wall construction process, and a high-pressure rotary jet grouting pile is constructed between any two adjacent bored piles to serve as a waterproof curtain.
In the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, after the bored pile is constructed to be drilled, the bored pile reinforcement cage is hoisted into the hole, the bored pile reinforcement cage is hoisted in multiple sections, and two bored pile reinforcement cages which are adjacent up and down are connected together;
the top end of the bored pile cage is symmetrically provided with at least two suspension points, the middle reinforcement hoop of the bored pile cage is symmetrically provided with at least two suspension points, and the bottom of the bored pile cage is provided with a hauling cable to limit the bored pile cage from swinging.
In the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, the secant pile comprises a first-order plain concrete pile and a second-order reinforced concrete pile, and any adjacent first-order plain concrete pile and any adjacent second-order reinforced concrete pile are mutually meshed together;
firstly constructing two adjacent first-order pile plain concrete piles, and then constructing a second-order reinforced concrete pile positioned between the two adjacent first-order pile plain concrete piles;
the occlusive pile is constructed by adopting a process of adding a flushing grab bucket and a full sleeve by a full-slewing drilling machine.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, the internal corner of the foundation pit is reinforced by adopting the double-shaft stirring piles, and any two adjacent double-shaft stirring piles are mutually overlapped.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, a drilling machine for constructing the drilled holes faces the subway business line and moves along the direction vertical to the railway business line, at least two reinforcing cables are arranged after the drilling machine is in place, one end of each reinforcing cable is connected with a ground anchor, and the other end of each reinforcing cable is connected to the drilling machine; the included angle between the cable and the ground plane is 45-60 degrees.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, the foundation pit is in a slender structure, at least three supports and one support are arranged in the vertical direction of the foundation pit according to the depth of the foundation pit to be excavated, the foundation pit is excavated in at least four layers in the vertical direction, each layer is excavated to the position below the support, then the support of the corresponding layer is installed, and then the excavation of earth is continued downwards until the foundation is excavated to the base;
and when the excavating equipment penetrates below the support, soil bodies on two sides are symmetrically excavated.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, the main structure of the subway station is a double-column three-span box type frame structure, and the main structure of the subway station consists of a bottom plate, a middle plate, a stand column, a side wall and a top plate;
the construction of the subway station main body follows the earth excavation operation, after one section of excavation is finished, one section of bottom plate is closed, and the subway station main body structure on the upper portion of the bottom plate is constructed in sequence.
According to the construction method of the subway deep foundation pit adjacent to the railway business line, preferably, after the construction of the subway station main body structure is completed and the top plate concrete reaches the design strength, a waterproof layer is laid, then earthwork backfilling is carried out, and waterproof clay is adopted within the range of at least 1m above the waterproof layer of the top plate; and (5) layering backfill earthwork and horizontally tamping.
Has the advantages that: the construction method has the advantages that the influence of the construction of the foundation pit of the subway station on the adjacent railway line is small, the construction efficiency is high, and the effect of protecting the adjacent railway line is achieved.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. Wherein:
FIG. 1 is a process flow diagram of a bite stake in an embodiment of the present invention;
FIG. 2 is a schematic view of a bite pile arrangement in an embodiment of the present invention;
FIG. 3 is a schematic illustration of the cable rope arrangement during rig construction according to an embodiment of the present invention;
FIG. 4 is a flow chart of a process of a dual-shaft stirring pile according to an embodiment of the present invention;
FIG. 5 is a flow chart of a process for making a jet grouting pile according to an embodiment of the present invention;
fig. 6 is a schematic diagram of support replacement in construction in a subway station main body in the embodiment of the present invention.
In the figure: 1. a railway operating line; 2. a drilling machine; 3. a guy rope; 4. supporting; 5. and (6) replacing the support.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.
In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are for convenience of description of the present invention only and do not require that the present invention must be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. The terms "connected" and "connected" used herein should be interpreted broadly, and may include, for example, a fixed connection or a detachable connection; they may be directly connected or indirectly connected through intermediate members, and specific meanings of the above terms will be understood by those skilled in the art as appropriate.
The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
According to the specific embodiment of the invention, as shown in fig. 1, the invention provides a construction method of a subway deep foundation pit adjacent to a railway business line, which comprises the following steps:
When the cast-in-situ bored pile is constructed, the long pile casing penetrates through a poor stratum and is embedded into a stable stratum at a section with poor geological conditions, and then the long pile casing is drilled to form a hole according to a rotary drilling mud retaining wall construction process. After the bored pile is constructed and formed into a hole, hoisting a bored pile reinforcement cage into the hole, wherein the bored pile reinforcement cage is hoisted in multiple sections, and two adjacent bored pile reinforcement cages up and down are connected together; the top end of the bored pile cage is symmetrically provided with at least two suspension points, the middle reinforcement hoop of the bored pile cage is symmetrically provided with at least two suspension points, and the bottom of the bored pile cage is provided with a hauling cable to limit the bored pile cage from swinging.
In the embodiment, rotary drilling is adopted for construction, and as the stratum contains a silt layer, a long casing process is adopted to penetrate through the silt layer, and the casing enters the clay layer to be not less than 1 m. And the lower part of the silt layer is constructed by adopting a mud retaining wall.
Before construction, the pile foundation position is accurately measured and placed, the drilling machine station position is flat and solid and meets a certain bearing capacity requirement, and when the platform bearing capacity cannot meet the requirement, replacement filling needs to be carried out to meet the site construction requirement. In order to prevent the mechanical overturn from invading the safety range of the business line, the construction of the drilling machine is carried out towards the railway business line, and the drilling machine is positioned in a direction vertical to the railway. The pile foundation with the pile diameter of 100cm is a pile casing with the diameter of 110cm, the pile foundation with the pile diameter of 150cm is a pile casing with the diameter of 160cm, and the drill bit is the same as the construction pile diameter for drilling. During construction, a steel casing penetrates through the silt layer and is embedded into the clay layer by adopting a vibration hammer, and then the steel casing is drilled into a hole according to a rotary drilling mud retaining wall construction process. Drilling below a silt layer to strictly control the quality of the slurry retaining wall and ensure the effectiveness of the retaining wall, and planning to adopt bentonite for slurry making; the performance indexes of the slurry are as follows: the specific gravity of the slurry is 1.1-1.3, the viscosity of the slurry is 18s-22s, the colloid rate is more than 90%, and the sand content of the newly prepared slurry is 4-8%. After the hole is formed, the specific gravity of the slurry after hole cleaning is controlled to be about 1.1; in the hole cleaning process, the slurry is supplemented, and the slurry surface is kept stable; and after the hole is cleaned, the steel reinforcement cage is immediately hoisted, and underwater concrete is timely poured, so that the possibility of necking down the pile foundation is reduced.
The drilling pile reinforcement cage belt is hoisted by adopting a truck crane, in order to reduce the influence of the hoisting of the reinforcement cage on the operation safety of a business line, the length of a single section of the reinforcement cage adjacent to the business line is less than or equal to 12m, binding and spot welding are combined between a main reinforcement and a stirrup of the reinforcement cage, and a pilot carefully checks whether each welding spot is firmly welded or not before installation so as to prevent the reinforcement cage from being scattered in the hoisting process. Hoisting the steel reinforcement cage by adopting a 4-point suspension method, wherein the maximum hoisting height is 19m, 2 hoisting points are symmetrically arranged at the position 2m inwards from the end head of the steel reinforcement cage, and a main hook of an automobile crane is used; 2 hoisting points are symmetrically arranged on the reinforcing hoop in the middle of the reinforcement cage, and an auxiliary hook of a truck crane is used. During hoisting, the bottom opening of the reinforcement cage is pulled by a hemp rope, so that the reinforcement cage is prevented from swinging back and forth to invade the limit. And after the hoisting of the steel reinforcement cage is finished, pouring concrete.
The secant pile comprises a first-order pile element concrete pile and a second-order reinforced concrete pile, and any adjacent first-order pile element concrete pile and any adjacent second-order reinforced concrete pile are mutually meshed together; firstly constructing two adjacent first-order pile plain concrete piles, and then constructing a second-order reinforced concrete pile positioned between the two adjacent first-order pile plain concrete piles; the occlusive pile is constructed by adopting a process of adding a flushing grab bucket and a full sleeve by a full-slewing drilling machine.
In this embodiment, the drilled interlocking pile is constructed by mechanical drilling, and the piles are mutually interlocked and arranged to form a foundation pit support structure. The method mainly adopts a soft method to cut and form holes, and the construction mainly adopts a scheme of a casing drilling machine and ultra-retarding concrete. The arrangement mode of the drilling secant pile adopts: a first-order pile plain concrete pile (hereinafter referred to as an A pile) and a second-order reinforced concrete pile (hereinafter referred to as a B pile) are spaced; the construction method comprises the steps of constructing the pile A firstly, constructing the pile B secondly, wherein the pile A concrete adopts super retarding concrete, the construction of the pile B needs to be completed before the initial setting of the pile A concrete, when the pile B is constructed, partial concrete of the adjacent pile A is cut off by utilizing the cutting capacity of a casing drilling machine, the engagement is realized, the construction sequence is A1 → A2 → B1 → A3 → B2 → …, and the like.
The occlusive pile is constructed by adopting a full-slewing drilling machine, a grab bucket and a full casing process, and the full casing is ahead of the soil sampling surface by more than 2.5m in the whole process, so that the stability of the hole wall is ensured.
Specifically, in the full-rotation process: the diameter of the sleeve is not less than the designed pile diameter, a first section of sleeve is hoisted and placed, and after the first section of sleeve is pressed into the soil (1.2-1.5 m is reserved on the ground so as to be convenient for taking over), the total station is adopted to measure the verticality of the sleeve from two different directions which are 90 degrees crossed, so that the verticality is ensured to meet the requirement. And pressing the first section of sleeve into the first section of sleeve to a depth of about 2.5-3 m. Taking soil in the hole of the grab bucket, and keeping the bottom opening of the sleeve to be at least 2.5m ahead of the excavation surface. According to the height difference between the soil surface in the hole and the bottom opening of the sleeve, the sleeve is lengthened and continuously pressed down, and the bottom opening of the sleeve is always kept to be at least 2.5m ahead of the excavation surface. And sequentially taking over and taking out the soil until the designed hole depth is reached, wherein the soil taking surface is 1.5m higher than the bottom opening of the sleeve when the hole is finished.
In the rotary drilling process: the rotary drilling rig is provided with a casing driver, the casing driver presses down the casing in the construction process, the drill bit follows up the soil taking, and the casing needs to be ensured to be 2.5m ahead of the soil taking surface in the soil taking process so as to ensure the stability of the stratum. And sequentially taking over and taking out the soil until the designed hole depth is reached, wherein the soil taking surface is 1.5m higher than the bottom opening of the sleeve when the hole is finished.
After the construction of the A1 and A2 piles, the middle B1 pile is constructed, the pile driver is moved to the position of the B1 pile, concrete is cut by a steel sleeve to realize engagement, and the cutting amount is 20 cm.
The steel reinforcement cage hoisting operation steps of the second-order reinforced concrete pile in the occlusive pile are the same as the steel reinforcement cage hoisting operation in the cast-in-situ bored pile, and the detailed description is omitted here.
And reinforcing the internal corner of the foundation pit by adopting the double-shaft stirring piles, and overlapping any two adjacent double-shaft stirring piles.
The high-pressure jet grouting pile is constructed between any two adjacent cast-in-place bored piles to serve as a waterproof curtain, cement slurry is horizontally sprayed into a soil body at a high speed by a special spray head at the end of a drill rod by using a high-pressure pump, the soil layer is cut by means of the impact force of liquid, the drill rod rotates at a certain speed and slowly lifts at a low speed, the soil body and the cement slurry are fully stirred, mixed and solidified, and a cylindrical consolidation body (namely the jet grouting pile) with certain strength is formed, so that the foundation is reinforced.
In the embodiment, the water-cement ratio of the cement slurry of the high-pressure rotary jet pile is preferably 0.7-1.0, the cement mixing amount of the double-pipe rotary jet pile is 180kg/m, and the cement yield of the triple-pipe rotary jet pile is 250 kg/m; when the building enclosure is constructed, pile arrangement construction is carried out firstly, and then rotary jet grouting pile construction is carried out; the construction operation sequence of the jet grouting pile adopts a hole-separating and sequencing mode, and the time interval of the jet grouting of adjacent holes is not more than 24 h.
When injecting and grouting, when the slurry return amount of the orifice is more than 20% of the grouting amount, adopting measures such as improving the injection pressure and the like; when the condition that the orifice does not return slurry due to slurry leakage occurs, stopping the grouting pipe at the position where the slurry does not return, continuously spraying and grouting, and simultaneously adopting measures of filling coarse sand from the orifice, doping a quick setting agent into the grouting liquid and the like until the orifice returns slurry; and after the injection grouting, when the slurry is separated out and the liquid level is lowered, the slurry is supplemented.
When the jet grouting stops in midway due to a cause, the jet grouting is continuously lapped with the grouting body before the jet grouting is stopped, and the lapping length is not less than 500 mm; the lifting speed of the jet grouting pile is preferably 0.08-0.15 m/min, and a re-spraying process is adopted. The unconfined compressive strength qu of the double-pipe rotary jet grouting pile for 28 days is more than or equal to 1.0MPa, and the permeability coefficient is less than or equal to 1.0 multiplied by 10 < -7 >/cm/s; the unconfined compressive strength qu of the triple-pipe jet grouting pile for 28 days is more than or equal to 1.2MPa, and the permeability coefficient is less than or equal to 1.0 x 10-7 cm/s.
The shape of the consolidation body can be controlled by adjusting the rotary spraying pressure and the grouting amount, changing the moving direction and the lifting speed of the nozzle. In the construction, lifting and rotating grouting are adopted, the formation of deep positions is considered, when bottom spraying is carried out, the spraying pressure is increased, repeated rotary spraying is carried out or the rotating lifting speed of the nozzles is reduced, and the pressure can be properly increased and the rotating lifting speed of the nozzles can be properly reduced aiming at different soil layers (hard soil), so that a solidification body is uniform, and the difference of pile diameters is ensured to be small.
When the lifting of the rotary spraying pipe is close to the pile top, the lifting speed is slowed down from 1.0 meter below the pile top, the rotary spraying pipe is lifted upwards to the pile top surface at a low speed after being sprayed for a plurality of seconds, the conveying of cement paste (water and wind) is stopped when the height of the paste top surface meets the requirement, the rotary spraying pipe is lifted out of the ground in a rotating mode, and the drilling machine is turned off.
In the construction process, each unit adopts a construction method of jumping; properly reducing the guniting pressure in the high-compression soil layer; the lifting speed and the rotating speed are accelerated, so that the hole stringing is prevented. In the construction process of the jet grouting pile, observation of reinforced peripheral stratums is enhanced, and when the stratums are found to have a rising trend, grouting pressure is reduced, and stability of the railway business line roadbed is guaranteed.
The drilling machines for constructing the cast-in-situ bored piles, the secant piles, the high-pressure jet grouting piles and the double-shaft stirring piles face the subway business line and move along the direction vertical to the railway business line 1, the drilling machines 2 are arranged with at least two reinforcing cables after being in place, one end of each reinforcing cable is connected with the ground anchor, and the other end of each reinforcing cable is connected to the drilling machines 2; the included angle between the guy rope 3 and the ground plane is 45-60 degrees.
In the embodiment, after a drilling machine 1 is in place, two reinforcing cable ropes 3 forming a certain angle are arranged, the cable ropes 3 are steel wire ropes, one ends of the cable ropes are tied to a ground anchor, the other ends of the cable ropes are connected with the drilling machine 2, the cable ropes 3 are connected with the ground anchor through basket bolts, and the included angle between the cable ropes 3 and the ground plane is generally controlled to be 45-60 degrees, so that the stability of machinery is ensured; the connection point of the hawser 3 to the rig 2 is arranged in an upper middle position of the rig 2.
When a foundation pit is excavated, a main machine station is located on a construction sidewalk far away from a railway side, machines such as a flat car only pass close to the railway side are not used as a construction site of large-scale equipment such as hoisting equipment, a long-arm excavator station is used for unearthing at the side of the foundation pit, a 75t crawler crane is used for installing steel supports, the maximum hoisting height of the crawler crane is 10m, and the steel supports face the foundation pit station during hoisting operation.
The deep foundation pit excavation construction is based on the principle of ensuring construction, surrounding environment safety and node construction period. Strictly obey the "spatiotemporal effect" theory. The sequential method of the earth excavation must be consistent with the design working condition, the key points of ' segmentation, layering and time limitation ' are mastered strictly according to the space-time effect theory, and the following ' supporting along with excavation is followed; excavating and supporting simultaneously; upper support in limited time; the main structure follows the construction principle of firstly in the middle and then on two sides to form flow operation, thereby ensuring the rapid construction on the premise of ensuring the safety and quality of the engineering. The earthwork retreats and digs and should strictly guarantee that the support follows up in time, and both sides are in the middle of earlier in the excavation process, can guarantee that both sides reserve the soil body dado, reduce fender pile's cantilever time and cantilever length. The width of the exposed part of each step of excavation is controlled to be 3-6 m.
The deep foundation pit excavation must be carried out after the pile top crown beam and the first concrete support are completely constructed and reach the design strength. According to the design, the overloading is less than or equal to 20KPa within the range of 1 time of the piling load at the periphery of the foundation pit, the piling is not allowed within the range of 1m at the periphery of the foundation pit, the piling is not more than 1.5m high outside the range of 1m, and the piling is not allowed within the range of 3m of the foundation pit if the soil quality is poor.
Carrying out well point (pipe well) dewatering according to a special dewatering scheme, ensuring that the underground water level is below 1m of an excavation surface, arranging a concrete water retaining wall with the height of 50cm around the foundation pit, and arranging a 30 cm-30 cm concrete intercepting ditch around the water retaining wall for intercepting and draining surface water; and a drainage ditch and a water collection well are arranged in the foundation pit, a submersible pump is equipped to pump and discharge water out of the pit in time, and the water interception ditch is precipitated by a three-stage sedimentation tank and then discharged into a municipal pipe network.
When the machine is used for digging soil, the bottom of the pit is manually leveled when a soil layer with the thickness of 300mm is reserved, and the groove is tested according to the program.
The excavating machinery and vehicles can not directly walk on the supports for operation, and the excavating machinery is strictly forbidden to collide the supports, the upright posts, the well point pipes and the fender piles.
Specifically, the vertical excavation step of the foundation pit comprises the steps of firstly, preparing for construction, enclosing and blocking a construction site, dredging traffic and moving and changing pipelines; constructing a guide wall of a foundation pit enclosure structure, constructing an occlusive pile and a drilled pile; and (4) manufacturing a precipitation well, precipitating until the precipitation reaches 1 meter below the excavation surface each time, and excavating downwards until the excavation surface for the first time. And secondly, constructing a crown beam and a first reinforced concrete support, and excavating downwards to a second excavation surface. Thirdly, excavating a foundation pit layer by layer from top to bottom, and erecting each support 4 after excavating to a position 0.5m below the support 4; and when the height mark of the bottom surface of the foundation pit is excavated to be 0.2-0.3 m above the elevation of the bottom surface of the foundation pit, manually excavating to the bottom of the foundation pit, treating the bottom of the foundation pit, constructing a grounding grid, and laying a cushion layer. And fourthly, paving a bottom plate waterproof layer and a fine aggregate concrete protective layer, pouring a main structure bottom plate, a bottom longitudinal beam and a part of side walls, setting water drain holes and dismantling well point pipes after the concrete strength of the bottom plate and the side walls (beams) reaches the design strength. And fifthly, dismantling the lowest steel pipe support, continuously pouring the side wall upwards, applying a side wall waterproof layer and applying a support replacement 5. And sixthly, removing the third support, pouring the side wall and the middle plate, and removing the second steel support after the strength of the middle plate concrete reaches the design strength. And seventhly, continuously pouring and constructing the waterproof layer of the side wall, the waterproof layer of the top plate and the waterproof layer of the top plate upwards. And eighthly, pouring the coping concrete after the strength of the top plate concrete reaches the design strength, removing the first reinforced concrete support, removing the replacement support 5, migrating the pipeline and backfilling the top plate with covered soil, and recovering road traffic and original ground. The weep hole is closed. And constructing the internal structure of the main body.
And during longitudinal excavation, the excavation length of each section of the first layer is about 6m, earthwork in the section is finished within 8 hours, and then the support of the section is installed and prestress is applied within 8 hours. In the excavation of the earthwork on the second layer and below, the excavation length of each small section is about 3m, the earthwork in the small section is completed within 8 hours, and then the support of the section is installed and the prestress is applied within 8 hours. The longitudinal reserved gradient is 1:2 when the silt layer is excavated, the longitudinal gradient of the clay layer is 1:1.5, and the section with more stable geology in the rock layer can be 1:1.
The end well part of the foundation pit is constructed by adopting a basin-type excavation method, soil at the middle triangular area part of the straight support and the inclined support is excavated firstly, then soil below the inclined support of the end well is excavated, and finally soil at the straight support area is excavated to realize relatively symmetrical and balanced excavation. And (4) leaving a circle of soil body which props against the retaining wall at two sides of the foundation pit, finally excavating the soil body in the lower region of the support, and installing the support at the position. And (3) layering from the middle to two sides, excavating in small sections in a limited time, and erecting steel supports in real time according to design requirements to reduce the exposure time of the foundation pit as much as possible.
The steel shotcrete, steel purlin adopt 75t crawler crane hoist and mount construction, and the clear distance of crawler crane apart from foundation ditch limit barricade is not less than 1m during the construction, and the station position is located the foundation ditch and keeps away from the railway side, and perpendicular to railway business line direction station position, and the biggest vertical height of crawler crane big arm is not more than 10m to guarantee business line construction safety.
The steel support is hoisted by two points, the hoisting point is generally about 0.3L away from the end part, and the balance and stability are noticed during hoisting, so that the hoisting cannot be too fast. So as to avoid safety accidents caused by falling of the steel support due to collision with the erected steel support.
Before the steel support is placed, the steel support is required to be placed right above the central line of the stable enclosing purlin and then slowly placed down, and the steel support is placed on the enclosing purlin. After the elevation positions and horizontal positions of the two ends are adjusted to be within the allowable error range, the pre-axial force application is started.
And (3) dismantling the steel support, and dismantling the support after the strength of the structural concrete in the previous process reaches the design requirement. The mechanical station position is consistent with the erection station position during dismantling, and the dismantling process comprises the following steps: firstly, the steel support is hung by a crawler to prevent falling → secondly, pre-applied axial force is eliminated, the connection between the steel support and the steel purlin is loosened → the steel support is hung section by section.
During dismantling, the steel support is slightly supported at two ends by using a crane truck, a jack is arranged at the movable end, axial force is applied until the steel wedge is loosened, the steel wedge is taken out, and the steel wedge is unloaded step by step until the steel wedge is taken out to hoist the steel support.
And 3, constructing a main structure of the subway station, wherein the main structure of the subway station is constructed in a mode of longitudinal segmentation, vertical layering and from bottom to top.
The subway station main body structure is a double-column three-span box type frame structure and consists of a bottom plate, a middle plate, stand columns, side walls and a top plate; the construction of the subway station main body follows the earth excavation operation, after one section of excavation is finished, one section of bottom plate is closed, and the subway station main body structure on the upper portion of the bottom plate is constructed in sequence.
In the embodiment, the bottom plate is 900mm thick, the middle plate is 400mm thick, the top plate is 800mm thick, and the side walls are 700mm thick, and C35 and P8 concrete are poured.
The construction of the main structure is longitudinally segmented according to the designed construction joint position, and the length of each segment is about 20 m. The construction joints are located near the spans of the longitudinal columns 1/3-1/4 and take care of the integrity of the internal facilities of the structure as much as possible. Follow "longitudinal segmentation during the construction, vertical layering, follow supreme construction principle, vertical layering down: bottom plate → negative two-layer side wall, upright column → middle plate → negative one-layer side wall, upright column → top plate. The main body construction is followed closely by the earthwork excavation operation, one section is excavated, one section of bottom plate is sealed, and the upper structure is constructed according to the sequence.
In this embodiment, the waterproof layer should in time be laid after roof concrete reaches design intensity, adopts the clay of water proof in 1 meter above the roof waterproof layer, and the water content should be the optimum water content, must not adopt good soil of water permeability such as sand, miscellaneous fill. The backfill soil at other parts preferably utilizes the soil dug in the foundation trench, but the following requirements should be met: the stone chips contain no organic impurities and have the particle size of not more than 50 mm; crushed stone soil, sandy soil and blasting stone slag, the maximum particle size of which does not exceed 2/3 of the thickness of each layer of bedding, can be used as a filler below a surface layer; the broken grass and soil with the organic matter content not more than 8 percent can only be used for filling without compaction requirement; silt and mucky soil generally cannot be used as the soil material.
The backfilled cohesive soil is filled at the optimum water content, for example, if the water content is larger, the cohesive soil is loosened and dried in the air, or dry soil is added and mixed uniformly; if the moisture content is low, it can be wetted by sprinkling water and increased in the number of compaction passes or crushed by using heavy-duty compacting machinery. The main structure must reach the designed strength and then be backfilled. Before the earthwork is backfilled, accumulated water and sundries on the top plate are cleaned, the deficient soil conforming to the backfilling is compacted, and the earthwork can be backfilled after the earthwork is qualified through experience inspection. Backfilling is carried out by layering and horizontal tamping; when the backfill elevations of the foundation pit are inconsistent, the foundation pit is tamped from the bottom along with the layer; the thickness of the soil material backfilled each time is not more than 0.3 m.
When the bulldozer is used for filling soil, layered filling from bottom to top is required, and large-slope soil pushing is not required to be adopted for pushing instead of pressing, so that the high-rise slope is in the near future, and a layered and one-step pushing filling method is not required. The earth-moving backfill of the bulldozer can adopt a method of piling and centralizing and one-time conveying so as to reduce earth-moving leakage. The soil filling procedure preferably adopts a longitudinal paving and filling sequence, the distance from the soil digging section to the soil filling section is preferably 40-60 m, the soil is rolled by a bulldozer which drives back and forth, and the crawler belts are overlapped by half.
The road roller is used for filling and compacting, and a method of thin filling, slow driving and repeated use is adopted. The rolling direction is gradually pressed towards the middle from two sides, the width of each overlapping of the rolling wheels is about 15-25 cm, and the edges of the side slopes and the corners cannot be compacted, and the side slopes and the corners can be compacted by manpower tamping or small-sized tamping machines. Filling the ground wall, column and foundation, and ensuring the distance between the road roller and the ground wall, column and foundation to be not less than 0.5 m. After each layer is rolled, the surface is roughened by hand or by machine (bulldozer) to facilitate joining.
Measuring the geometric state of the railway track before foundation pit construction, and monitoring the deformation of a railway business line and the deformation of a foundation pit in real time in the construction process; and when the monitored deformation reaches the pre-inspection alarm value, performing construction treatment in time.
In the embodiment, the settlement and deformation of railway-related buildings and facilities such as railway subgrade, railway tracks and turnouts are monitored; and peripheral buildings and underground pipelines are settled and deformed, roads and ground surface are settled and deformed, the enclosure structure is settled and deformed, the supporting shaft force is exerted, and the upright posts are settled and raised.
Monitoring should be conducted in the whole construction process, and according to a specified program, each party involved in construction is notified, and consultation is conducted in time or construction measures are adjusted. The construction is strictly organized according to a three-level early warning mechanism, and the judgment and the processing of the three-level early warning state are detailed in the following table.
Three-stage early warning state judging and processing table
Because the deformation and the peristalsis of the stratum and the transmission of the ground stress lag behind the excavation of the stratum, the adverse effect of the foundation pit construction of the subway station on the railway possibly occurs for a period of time after the foundation pit construction, the key monitoring items of the railway are properly prolonged, and the frequency of the measurement is finally consistent with the normal maintenance and maintenance frequency of the track. The monitoring should be continued until the sedimentation is stable, and the monitoring should be stopped when the sedimentation rate is less than or equal to 0.05 mm/day for 3 months continuously.
In conclusion, in the technical scheme of the construction method of the subway neighbor railway business line provided by the invention, the influence of the construction of the subway station foundation pit on the adjacent railway line is small, the construction efficiency is high, and the effect of protecting the adjacent railway line is achieved.
It should be understood that the above description is exemplary only and that the embodiments of the present application are not intended to be limiting.
The above description is only exemplary of the invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the invention is intended to be covered by the appended claims.
Claims (10)
1. A construction method of a subway deep foundation pit adjacent to a railway business line is characterized by comprising the following steps:
step 1, constructing a foundation pit supporting structure; the main body of the foundation pit mainly adopts a supporting structure which combines an occlusive pile with an inner support to support the foundation pit and also serves as a waterproof curtain, and a bored pile and a triple-pipe jet grouting pile waterproof curtain are combined with the inner support to support the foundation pit at a section with poor geological conditions adjacent to the side of a railway or a part of the foundation pit with a high-voltage line passing through;
step 2, carrying out foundation pit earthwork excavation construction, wherein the foundation pit is longitudinally segmented firstly and then vertically layered, is supported by a groove, is supported firstly and then excavated, and is excavated along with the support;
step 3, constructing a main body structure of the subway station, wherein the main body structure of the subway station is constructed by an open cut method, and is constructed in a longitudinal segmentation, vertical layering and bottom-to-top mode;
and 4, backfilling earthwork after the main body structure of the subway station reaches the design strength, and backfilling the foundation pit symmetrically in layers.
2. The construction method of the subway deep foundation pit adjacent to the railway business line according to claim 1, characterized in that the geometrical state of the railway track is measured before the foundation pit is constructed, and the deformation of the railway business line and the deformation of the foundation pit are monitored in real time during the construction process;
and when the monitored deformation reaches the pre-inspection alarm value, performing construction treatment in time.
3. The construction method of the subway deep foundation pit adjacent to the railway business line according to claim 2, wherein when the bored piles are constructed, the long pile casing is adopted to penetrate through the poor stratum to be embedded into the stable stratum at the section with poor geological conditions, then the holes are drilled according to the rotary drilling mud retaining wall construction process, and a high-pressure rotary jet grouting pile is constructed between any two adjacent bored piles to serve as a waterproof curtain.
4. The method as claimed in claim 3, wherein after the hole is formed in the bored pile, the bored pile cage is hoisted into the hole, the bored pile cage is hoisted in multiple stages, and two bored pile cages adjacent to each other up and down are connected together;
the top end of the bored pile cage is symmetrically provided with at least two suspension points, the middle reinforcement hoop of the bored pile cage is symmetrically provided with at least two suspension points, and the bottom of the bored pile cage is provided with a hauling cable to limit the bored pile cage from swinging.
5. The construction method of a subway deep foundation pit adjacent to a railway business line as claimed in claim 2, wherein said secant pile comprises a first-order plain concrete pile and a second-order reinforced concrete pile, any adjacent first-order plain concrete pile and any adjacent second-order reinforced concrete pile are mutually secant together;
firstly constructing two adjacent first-order pile plain concrete piles, and then constructing a second-order reinforced concrete pile positioned between the two adjacent first-order pile plain concrete piles;
the occlusive pile is constructed by adopting a process of adding a flushing grab bucket and a full sleeve by a full-slewing drilling machine.
6. The construction method of the subway deep foundation pit adjacent to the railway business line according to claim 2, characterized in that the internal corner of the foundation pit is reinforced by using double-shaft stirring piles, and any two adjacent double-shaft stirring piles are overlapped with each other.
7. A construction method for a subway deep foundation pit adjacent to a railway business line according to any one of claims 1 to 6, wherein a drilling machine for drilling the hole faces the subway business line and moves along the direction perpendicular to the railway business line, at least two reinforcing cables are arranged after the drilling machine is in place, one end of each reinforcing cable is connected with a ground anchor, and the other end of each reinforcing cable is connected to the drilling machine; the included angle between the cable and the ground plane is 45-60 degrees.
8. The construction method of the subway deep foundation pit adjacent to the railway business line as claimed in claim 1, wherein the foundation pit is in an elongated structure, at least three supports and one support are arranged vertically in the foundation pit according to the depth of the excavated foundation pit, the foundation pit is excavated vertically in at least four layers, each layer is excavated to a position below the support, then the support of the corresponding layer is installed, and then the excavation of earth is continued downwards until the foundation is excavated to the base;
and when the excavating equipment penetrates below the support, soil bodies on two sides are symmetrically excavated.
9. The construction method of the subway deep foundation pit adjacent to the railway business line as claimed in claim 1, wherein the main structure of the subway station is a double-column three-span box type frame structure, and the main structure of the subway station is composed of a bottom plate, a middle plate, upright columns, side walls and a top plate;
the construction of the subway station main body follows the earth excavation operation, after one section of excavation is finished, one section of bottom plate is closed, and the subway station main body structure on the upper portion of the bottom plate is constructed in sequence.
10. The construction method of the subway deep foundation pit adjacent to the railway business line according to claim 9, wherein a waterproof layer is laid after the construction of the subway station main body structure is completed and the roof concrete reaches the designed strength, then earth backfilling is carried out, and waterproof clay is adopted within a range of at least 1 meter above the roof waterproof layer; and (5) layering backfill earthwork and horizontally tamping.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115467339A (en) * | 2022-09-17 | 2022-12-13 | 中建五局土木工程有限公司 | Construction method of abutment foundation of river under soft soil condition of near tunnel shallow covering layer |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111576431A (en) * | 2020-05-25 | 2020-08-25 | 中铁隧道局集团有限公司 | Excavation method for foundation pit of four-layer subway station |
-
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- 2022-05-20 CN CN202210557281.5A patent/CN114991165A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111576431A (en) * | 2020-05-25 | 2020-08-25 | 中铁隧道局集团有限公司 | Excavation method for foundation pit of four-layer subway station |
Non-Patent Citations (3)
| Title |
|---|
| 孙中海等: "明挖地铁车站模板施工技术及支撑体系安全检算", 《建筑技术开发》 * |
| 岳地东等: "南京地铁新庄站深基坑关键设计技术", 《四川建筑科学研究》 * |
| 江苏省建设工程质量监督总站，南京市轨道交通建设工程质量安全监督站: "《城市轨道交通工程质量监督实务》", 30 November 2017, 南京：东南大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115467339A (en) * | 2022-09-17 | 2022-12-13 | 中建五局土木工程有限公司 | Construction method of abutment foundation of river under soft soil condition of near tunnel shallow covering layer |
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Application publication date: 20220902 |