CN111877314B

CN111877314B - Construction method for constructing underground continuous wall by adopting chain precast concrete piles

Info

Publication number: CN111877314B
Application number: CN202010542032.XA
Authority: CN
Inventors: 吴才德; 李福连; 张日红; 龚迪快; 华锦耀; 成怡冲
Original assignee: Ningbo Zcone High Tech Co ltd; Zhejiang Hongchen Construction Co ltd; ZHEJIANG HUAZHAN INSTITUTE OF ENGINEERING RESEARCH AND DESIGN
Current assignee: Ningbo Zcone High Tech Co ltd; Zhejiang Hongchen Construction Co ltd; Zhejiang Huazhan Research And Design Institute Co ltd
Priority date: 2020-06-15
Filing date: 2020-06-15
Publication date: 2021-08-24
Anticipated expiration: 2040-06-15
Also published as: CN111877314A

Abstract

The invention discloses a construction method for constructing an underground continuous wall by adopting chain precast concrete piles, which comprises the following steps of installing a prefabricated first positioning guide plate: one side of the first positioning guide plate is provided with a first arc-shaped convex block which is engaged with the first arc-shaped grooves of the parallel adjacent rectangular piles and can slide mutually, and the shape and the size of the first positioning guide plate are the same as the shape and the size of the cross section of the rectangular pile; still including the location leading truck location, the side rolls the cooperation all the time and the left first arc recess of rectangle stake and ball and rolls the cooperation all the time, the first arc lug of the first location deflector of rectangle stake right side lower extreme and the first arc recess of the adjacent rectangle stake of side by side sliding fit all the time around the in-process rectangle stake that the drilling rod sinks with the rectangle stake is synchronous to guarantee the positioning accuracy and the straightness that hangs down of this rectangle stake, sink to preset position until the rectangle stake. The construction method ensures that the positioning precision of the parallel adjacent piles is high, the verticality of the upper pile and the lower pile is good, and the construction efficiency is relatively high.

Description

Construction method for constructing underground continuous wall by adopting chain precast concrete piles

Technical Field

The invention relates to the technical field of building construction, in particular to a construction method for constructing an underground continuous wall by adopting chain precast concrete piles.

Background

The interlocking precast concrete pile is a pretensioning prestressed concrete hollow rectangular pile, namely a square pile or a rectangular pile, the outer contour of which is rectangular, the left side and the right side of which are respectively provided with two arc-shaped grooves, namely semi-elliptical grooves, and the pile is formed by adopting a centrifugal process. The water stop glue or water stop slurry is injected into the oval hole formed by folding the two arc-shaped grooves, namely the water stop hole, so that a continuous wall body can be formed underground in the continuous row construction of the chain concrete precast pile, and the chain concrete precast pile can be used as a temporary and permanent soil retaining, water stopping and bearing structure. The underground continuous wall can be used as a building enclosure structure in a foundation pit construction stage to play roles of water retaining and water stopping, and can also be used as a structural outer wall of a basement in a permanent use stage of the structure to play roles of water retaining and water stopping, namely the underground continuous wall is commonly called as 'two-in-one wall'. Compared with cast-in-place underground continuous walls and prefabricated integral underground continuous walls, the interlocking concrete prefabricated pile wall has the advantages of wall quality, water stop effect, economy, construction convenience (such as no need of heavy roads and large steel reinforcement cage hoisting and wall protection slurry) and environmental protection, and is widely applied.

In the early stage, the pile sinking construction of the chain precast concrete piles is mostly carried out by adopting a hammering method and a static pile pressing method, and the two methods inevitably extrude the surrounding soil body, so that the adjacent buildings, roads, underground structures and the like are displaced and even cracked. Therefore, the precast pile is mostly used in areas with low environmental protection requirements, and the applicability of the precast pile is greatly restricted. In order to overcome the pile sinking soil squeezing effect, the way of firstly conducting hole leading at the pile sinking position or excavating anti-squeezing ditches or stress release holes at the periphery is often adopted in the engineering, but as the hole leading and the pile sinking usually have longer time interval, the hole wall after the hole leading is often difficult to keep stable and collapse or shrink, and the adverse effect is also generated on the peripheral environment; in addition, the hole guiding and pile sinking are not synchronously implemented, which results in low construction efficiency.

In recent years, construction is gradually carried out by adopting a medium excavation method: through setting up the auger stem at chain concrete precast pile center, borrow soil guide hole along stake full length in the stake hole, hold simultaneously to the stake and press the pile sinking, can realize the side guide hole while the pile sinking. Compared with other methods, the soil squeezing effect of the middle digging method construction is obviously reduced, and the construction efficiency is greatly improved.

However, the prior excavation construction method still has the following defects: the continuous row construction of the interlocking concrete precast piles needs to form a flat wall surface, but the positioning precision of adjacent piles and the verticality of upper and lower piles in the interlocking concrete precast pile construction in the prior art are still difficult to ensure, so that the flatness of the wall surface of the underground continuous wall is still not ideal, and the construction efficiency is also not ideal; in addition, after the middle and upper section interlocking concrete precast piles in the prior art are sunk to a preset position, the spiral drill rod needs to be separated, another spiral drill rod is sleeved in a central hole of the upper section precast pile, the upper section precast pile sleeved with the spiral drill rod is lifted by a crane and is vertical to the upper section precast pile, and the spiral drill rod is fastened with an upper power head.

Disclosure of Invention

The invention aims to solve the technical problem of providing a construction method for constructing an underground continuous wall by using interlocked concrete precast piles, wherein the positioning precision of adjacent piles is relatively high, the verticality of upper and lower piles is relatively good, and the construction efficiency is relatively high.

The technical scheme of the invention is that a construction method for forming an underground continuous wall by adopting a chain concrete precast pile is provided, the chain concrete precast pile is a rectangular pile which is provided with a first central circular hole and first arc-shaped grooves symmetrically arranged at two sides, and the construction method comprises the following construction steps:

(1) paying off and positioning: measuring and paying off, excavating a foundation trench, and determining the pile position of a rectangular pile;

(2) and (3) guide wall construction: constructing cast-in-place concrete guide walls along two sides of the longitudinal axis of the pile position of the rectangular pile;

(3) installing a prefabricated first positioning guide plate: a first arc-shaped projection which is engaged with and can slide relative to a first arc-shaped groove of a parallel adjacent rectangular pile is arranged on one side of the first positioning guide plate, the other shapes and sizes of the first positioning guide plate are the same as the cross section shapes and sizes of the rectangular piles, pre-buried steel on the first positioning guide plate is welded with pre-buried steel at the bottom end of a lower-section rectangular pile, a second central circular hole of the first positioning guide plate is aligned with a first central circular hole of the lower-section rectangular pile, and a second arc-shaped groove of the first positioning guide plate is aligned with a first arc-shaped groove of the lower-section rectangular pile;

(4) hoisting the lower section of rectangular pile in place: hoisting the bundled lower-section rectangular pile above the pile position by a crawler crane through a steel wire rope, and placing the lower-section rectangular pile in a hydraulic clamp and a rectangular pile positioning guide hole of a second positioning guide plate of a positioning guide frame;

(5) fixing the lower section of rectangular pile: starting a hydraulic clamp, clamping and fixing a lower-section rectangular pile, fixing the hydraulic clamp with the bottom of a lower power head, namely a vibration hammer, of a long-spiral double-power-head pile machine through a flange assembly, and slidably fitting the hydraulic clamp on a plurality of upright guide rails fixed with a main mast of the long-spiral double-power-head pile machine, wherein two clamp plates of the hydraulic clamp are respectively provided with a second arc-shaped lug which is matched with first arc-shaped grooves on two sides of the lower-section rectangular pile so that the axis of a first central circular hole of the lower-section rectangular pile and the central lines of an upper power head and a lower power head of the long-spiral double-power-head pile machine are positioned on the same vertical line; unhooking the crane, correcting the verticality of the lower section rectangular pile, and downwards sliding the lower power head to press the bottom end of a lower flange disc in the flange assembly against the top end of the lower section rectangular pile;

(6) positioning a drill rod: a spiral drill rod which is arranged in an upper power head of the long-spiral double-power-head pile driver and has the length of 35-40 meters penetrates through a lower power head, is inserted into a first central circular hole of a lower section of rectangular pile and extends out of the lower end of the lower section of rectangular pile;

(7) positioning by a positioning guide frame: inserting a center hole positioning pipe into a third center circular hole of a third positioning guide plate and a first center circular hole of an adjacent upper section rectangular pile, and correcting the verticality of the center hole positioning pipe; an arc-shaped notch for the first arc-shaped bump of the first positioning guide plate to slide downwards is formed in the left side of the third positioning guide plate; adjusting and enabling a plurality of limiting idler wheels on the second positioning guide plate to tightly abut against the front side surface and the rear side surface of the lower rectangular pile, enabling a first ball arranged on the left side of the positioning guide frame to be matched and tightly abutted in a first arc-shaped groove on the left side of the lower rectangular pile, and enabling a first arc-shaped bump of a first positioning guide plate on the lower end of the right side of the lower rectangular pile to be matched and tightly abutted in a first arc-shaped groove of the adjacent rectangular piles;

(8) construction by a middle digging method: loosening the hydraulic clamp, driving the spiral drill rod to rotate reversely by the upper power head so as to open the reaming drill bit and take soil, simultaneously pressing the rectangular pile by the lower power head, enabling the spiral drill rod and the lower rectangular pile to sink synchronously, enabling the front side and the rear side of the lower rectangular pile to be in rolling fit with the limiting idler wheel all the time in the sinking process, enabling the first arc-shaped groove in the left side of the lower rectangular pile to be in rolling fit with the first ball all the time, enabling the first arc-shaped bump of the first positioning guide plate at the lower end of the right side of the lower rectangular pile to be in sliding fit with the first arc-shaped grooves of the parallel adjacent rectangular piles all the time, and accordingly ensuring the positioning accuracy and the perpendicularity of the lower rectangular pile until the lower rectangular pile sinks to a preset position;

(9) resetting the upper power head and the lower power head: rotating and lifting the power head to make the bottom end of the spiral drill rod have the length of an upper section of rectangular pile, and driving a lower flange disc in the flange assembly to be separated from a lower section of rectangular pile by the lower power head and lifting the lower flange disc to the initial position;

(10) positioning the upper section rectangular pile: repeating the steps (4) to (7), except that the object is converted from the lower section rectangular pile into the upper section rectangular pile;

(11) pile splicing: aligning the upper section rectangular pile and the lower section rectangular pile, correcting the verticality, and welding the embedded steel edges of the butt joint of the upper rectangular pile and the lower rectangular pile below the second positioning guide plate;

(12) repeating the step (8), except that the object is converted into an upper section rectangular pile from a lower section rectangular pile, and the spiral drill rod penetrates through the upper section rectangular pile and the lower section rectangular pile and extends out of the bottom end of the lower section rectangular pile until the upper section rectangular pile 6 and the lower section rectangular pile 9 which are butted sink to a preset position; repeating the step (9), so that the upper power head and the lower power head are reset, and the bottom end of the spiral drill rod is empty for the length of a lower section of rectangular pile;

(13) repeating the steps (3) to (12) repeatedly until an underground continuous wall formed by the interlocking concrete precast piles is formed, and forming oval water stop holes by two adjacent first arc-shaped grooves in parallel;

(14) grouting to the water stop hole: and grouting a water stop hole formed after the two adjacent first arc-shaped grooves are tightly attached by using a pressure grouting machine until the hole opening is flooded and solidified to play a waterproof role.

After the steps are adopted, the construction method for forming the underground continuous wall by adopting the chain precast concrete piles has the following advantages: the second arc-shaped convex blocks on the two clamping plates of the hydraulic fixture enable the axis of the first center circular hole of the rectangular pile and the center lines of the upper power head and the lower power head of the long-spiral double-power-head pile driver to be on the same vertical line, and perpendicularity is further guaranteed. By utilizing the first positioning guide plate with the shape and the size same as the cross section of the rectangular pile, the rectangular pile positioning guide hole of the second positioning guide plate, the third guide plate and the central hole positioning pipe, the front side and the back side of the rectangular pile are always in rolling fit with the limiting idler wheel of the second positioning guide plate and the first arc-shaped groove on the left side of the rectangular pile is always in rolling fit with the first ball of the second positioning guide plate in the sinking process, and the first arc-shaped bump of the first positioning guide plate at the lower end of the right side of the rectangular pile is always in sliding fit with the first arc-shaped groove of the adjacent rectangular pile, so that the high positioning precision and the accurate verticality of the rectangular pile are effectively ensured, the flatness of the underground continuous wall surface is very ideal, and the technical defects of large friction resistance and easy dislocation between concave-convex structures caused by the full-length male-female fit of the adjacent piles in the prior art are overcome The contact area of the limiting idler wheel and the first bump with the rectangular pile is small, the friction resistance is small, the guiding effect is good, the positioning accuracy of adjacent piles of the rectangular pile is high, the verticality of the upper pile and the lower pile is accurate, the construction efficiency is high, and the quality of the underground diaphragm wall is well guaranteed.

In addition, after the lower section of rectangular pile is sunk to a preset position, the power head is rotated and lifted up to enable the bottom end of the spiral drill rod with the length of 35-40 meters to be free of the length of the upper section of rectangular pile, after the upper section of pile is positioned and corrected for verticality, the spiral drill rod is sleeved in the central hole of the upper section of precast pile and penetrates through the lower section of precast pile and extends out of the bottom end of the lower section of rectangular pile, and pile sinking operation can be achieved by adopting a middle digging method.

Further, the long-spiral double-power-head pile machine comprises a main machine, a main mast fixed with the main machine, an upper power head which is connected to the main mast in a sliding mode, connected with a winch on the main machine through a first steel wire rope and used for clamping a spiral drill rod with the length of 35-40 meters and driving the spiral drill rod to rotate, a lower power head which is a vibration hammer and connected to the main mast in a sliding mode, connected with another winch on the main machine through a second steel wire rope and used for pressing a rectangular pile downwards, a hydraulic clamp which is connected to the main mast in a sliding mode, fixed to the lower power head through a flange assembly and used for clamping the rectangular pile, and a reaming drill bit is arranged on the end portion, extending out of the bottom end of the rectangular pile, of the spiral drill rod penetrating through the vibration hammer and a first central circular hole of the rectangular pile. After the long-spiral double-power-head pile machine adopts the structure, the pile machine is reasonable in overall layout and relatively simple in structure, operation in the construction steps of spiral reaming and rectangular sinking piles which are synchronously performed in the method is stable and reliable, the equipment is time-saving and labor-saving in operation, labor intensity of operators is greatly relieved, construction efficiency is greatly improved, accurate verticality of the sinking piles and positioning accuracy of adjacent piles can be guaranteed, and therefore high quality, such as good flatness and good waterproof effect of the underground continuous wall are further guaranteed.

Further, the hydraulic fixture include the mount, two tight hydro-cylinders of clamp that the symmetry was installed in the mount both sides are fixed at the splint that press from both sides tight hydro-cylinder piston rod free end separately, have on every splint coincide with the first arc recess of rectangular pile both sides so that the axis of the first center round hole of rectangular pile and the second arc lug of the central line on same plumb line of upper and lower unit head, same end of two splint is through respective second ball roll fit on the guide rail of mount, the mount fixed with the unit head down through flange subassembly, the mount on have be used for with fix many stand guide rail sliding fit's staple bolts on the mast. After the hydraulic fixture adopts the structure, the axial line of the first central circular hole of the rectangular pile and the central lines of the upper power head and the lower power head can be effectively ensured to be on the same vertical line, so that the high positioning precision, the accurate verticality and the high construction efficiency of the rectangular pile sunk by the method are further ensured, and the high quality, such as good flatness and good waterproof effect of the underground continuous wall are further ensured.

Furthermore, the number of the upright post guide rails is two. After the structure is adopted, the hydraulic clamp can run more stably and flexibly up and down.

Furthermore, the positioning guide frame comprises a rectangular frame made of steel, height adjusting devices are arranged on four legs of the rectangular frame, a second positioning guide plate and a third positioning guide plate are arranged at the top of the positioning guide frame, a rectangular pile positioning guide hole is formed in the second positioning guide plate, a first ball for engaging with and rolling along a first arc-shaped groove on the left side of the rectangular pile so as to enable the rectangular pile to slide downwards is arranged on the second positioning guide plate on the left side of the rectangular pile positioning guide hole, a plurality of limiting rollers for abutting against the front side and the rear side of the rectangular pile and rolling so as to enable the rectangular pile to slide downwards are symmetrically arranged on the second positioning guide plate on the front side and the rear side of the rectangular pile positioning guide hole, an arc-shaped notch for the first arc-shaped lug of the first positioning guide plate to slide downwards is formed in the left side of the third positioning guide plate, a third central round hole for a central hole positioning pipe to pass through and be inserted into a first central round hole of an adjacent rectangular pile which has been sunk in place is formed in the center of the third positioning guide plate, and the distance between the center perpendicular line of the third center circular hole and the center perpendicular line of the rectangular pile positioning guide hole is equal to the distance between the center perpendicular lines of the center holes of the two parallel adjacent rectangular piles. It is understood that positioning refers to positioning the rectangular pile in the transverse or horizontal direction, and guiding refers to guiding the rectangular pile in the vertical direction. After the structure above adopting, the positioning guide frame further effectively guarantees the high positioning accuracy and the accurate straightness that hangs down of rectangular pile, makes the roughness of underground continuous wall face very ideal, has overcome the produced big frictional resistance of adjacent stake full length male-female cooperation and the technical defect of easy dislocation between the concave-convex structure among the prior art simultaneously again, because the second ball, spacing gyro wheel and first lug are little with rectangular pile area of contact, its frictional resistance is little, it is effectual to lead, further improved the positioning accuracy and the accurate straightness that hangs down of rectangular pile, further improved the efficiency of construction, further guaranteed the quality of underground continuous wall such as roughness and water-proof effects.

Furthermore, the top surface of the second positioning guide plate and the top surface of the third positioning guide plate are on the same plane, the top surface of the second positioning guide plate is perpendicular to the hole wall of the rectangular pile positioning guide hole, and the top surface of the third positioning guide plate is perpendicular to the hole wall of the third center circular hole; the positioning guide frame further comprises a device for adjusting the levelness of the top surface of the second positioning guide plate and the top surface of the third positioning guide plate: the top surface of the lower beam of the rectangular frame is parallel to the top surfaces of the second positioning guide plate and the third positioning guide plate, and a level gauge for leveling the levelness of the top surface of the lower beam is arranged on the lower beam. After the structure above is adopted, the levelness of the top surface of the positioning guide frame, namely the verticality of the rectangular guide hole surface and the verticality of the hole surface of the third central round hole, is further ensured, the positioning precision and the accurate verticality of the rectangular pile are further improved, and the construction efficiency is further improved.

Further, the height adjusting device on each leg is structured as follows: the bottom of each leg is provided with a lower convex cylinder, a rotating sleeve is sleeved on the cylinder, the cylinder and the rotating sleeve are provided with a structure for limiting the axial positions of the cylinder and the rotating sleeve, the middle lower section of the rotating sleeve is provided with a threaded hole, and the threaded hole is screwed with a screw rod with a base plate to adjust the height position of each leg. After the structure is adopted, the levelness of the top surface of the positioning frame, namely the verticality of the rectangular guide hole surface and the verticality of the hole surface of the third central round hole, can be adjusted more accurately, labor-saving and flexibly.

Furthermore, the number of the limiting idler wheels is eight, four second positioning guide plates are arranged on the front side of the rectangular pile positioning guide hole, and four second positioning guide plates are arranged on the rear side of the rectangular pile positioning guide hole; the structure of each limiting roller is as follows: the axis of the roller shaft is parallel to the front and the back of the rectangular guide hole, two ends of the roller shaft are rotatably matched on a second positioning guide plate on the front side or the back side of the rectangular pile positioning guide hole, two rollers on each roller shaft are accommodated in a notch of the second positioning guide plate, the opening of the second positioning guide plate faces the rectangular guide hole, elongated slots for the roller shaft to move back and forth are formed in the second positioning guide plates on two ends of the notch, and the front outer side and the back outer side of the second positioning guide plate are provided with adjusting screw and nut devices for adjusting the front and back positions of the roller shaft so that the roller can be tightly pressed against the front side face or the back side face of the rectangular pile to roll or separate from the front side face or the back side face of the rectangular pile.

After the structure is adopted, the limiting idler wheel is simple in structure, convenient to adjust, reliable and flexible to operate, the idler wheel and the front side and the rear side of the rectangular pile roll more flexibly and reliably, and good guidance quality and positioning accuracy and accurate perpendicularity of the rectangular pile in the construction process are further guaranteed.

Furthermore, two first arc-shaped grooves are formed in each side of each rectangular pile; two first arc-shaped convex blocks are arranged on one side of each first positioning guide plate; two second arc-shaped convex blocks are arranged on each clamping plate of the hydraulic clamp; two upright post guide rails are fixed on the main mast; two first balls are arranged on the left side of the positioning guide frame; the number of the arc-shaped notches on the left side of the third positioning guide plate is two. After the structure more than adopting, second arc lug and first ball are better with first arc recess sliding fit's mechanical properties, and are more stable, reliable, and the guidance quality is better, has further guaranteed the positioning accuracy and the accurate straightness that hangs down of rectangular pile.

Further, the structure of the first positioning guide plate is as follows: the plate body is a rectangular plate body with the same shape and size as the cross section of the rectangular pile, the center of the rectangular plate body is provided with a second central round hole with the diameter equal to that of a first central round hole of the rectangular pile and the axis of the hole and the axis of the first central round hole of the rectangular pile on the same vertical line, one side of the first positioning guide plate is provided with a first arc-shaped lug which is inosculated with and can slide with a first arc-shaped groove of the adjacent rectangular pile, and the other side of the first positioning guide plate is provided with a second arc-shaped groove which is the same in shape and size as the first arc-shaped groove of the rectangular pile and has an arc surface on the same vertical plane; the first positioning guide plate is a concrete prefabricated part, and angle steel used for being welded with embedded steel at the bottom end of the rectangular pile is embedded in the top end of the first positioning guide plate. The thickness of the rectangular plate body of the first positioning guide plate is larger than 250 mm. After the structure is adopted by the first positioning guide plate, the strength is good, the manufacturing cost is low, the matching degree with the rectangular pile is high, the mechanical property is good, the structure is stable and reliable, the guide performance is good, and the positioning accuracy and the accurate verticality of the rectangular pile are further ensured.

Drawings

Fig. 1 is a schematic structural view of a section of an underground diaphragm wall constructed by using interlocking precast concrete piles in the method of the present invention.

FIG. 2 is a schematic view of the connection structure of the upper and lower sections of the rectangular pile in the method of the present invention.

FIG. 3 is a schematic structural diagram of a long-spiral double-power-head pile driver in the method of the present invention.

Fig. 4 is a schematic top view of a hydraulic clamp for rectangular piles in the method of the present invention.

FIG. 5 is a schematic top view of a hydraulic ram of the hydraulic clamp of FIG. 4.

Fig. 6 is a schematic front view of a hydraulic clamp for rectangular piles in the method of the present invention.

Fig. 7 is a schematic bottom view of a flange assembly in the method of the present invention.

FIG. 8 is a schematic structural diagram of a positioning guide frame in the method of the present invention.

Fig. 9 is a schematic top view of the first positioning guide plate according to the present invention.

Fig. 10 is a front view of the first positioning guide plate according to the present invention.

Shown in the figure are 1, a guide wall, 2, a rectangular pile, 3, a first central round hole, 4, a first arc-shaped groove, 5, a water stop hole, 6, an upper section of rectangular pile, 7, a lower end plate of the upper section of rectangular pile, 8, an upper end plate of the lower section of rectangular pile, 9, a lower section of rectangular pile, 10, a main mast, 11, a long spiral double-action-head pile machine, 12, a main machine, 13, a first steel wire rope, 14, an upper power head, 15, a spiral drill rod, 16, a lower power head, 17, a second steel wire rope, 18, a hydraulic clamp, 19, a reamer bit, 20, a flange component, 21, a guide rail, 22, a clamping plate, 23, a clamping oil cylinder, 24, a second arc-shaped convex block, 25, a second ball, 26, an annular sliding sleeve, 27, a stand guide rail, 28, a hoop, 29, a fixing frame, 30, a first ball, 31, a limiting roller, 32, a second positioning guide plate, 33, a rectangular pile positioning guide hole, 34 and a notch, 35. the positioning device comprises a central hole positioning pipe, 36, a positioning guide frame, 37, a third positioning guide plate, 38, a third central circular hole, 39, a level gauge, 40, a height adjusting device, 41, a rectangular frame, 42, a second arc-shaped groove, 43, angle steel, 44, a second central circular hole, 45, a first positioning guide plate, 46, a first arc-shaped convex block, 47, a rectangular plate body, 48, an upper flange plate, 49, a lower flange plate, 50, a connecting rod, 51 and a connecting bolt.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings. It is to be noted that the description of the embodiments is provided to aid understanding of the present invention, and is not intended to limit the present invention. In addition, the technical features involved in the respective embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As shown in fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6, fig. 7, fig. 8, fig. 9, fig. 10:

the invention discloses a construction method for forming an underground continuous wall by using a chain concrete precast pile, wherein the chain concrete precast pile is a rectangular pile 2 which is provided with a first central circular hole 3 and first arc-shaped grooves 4 symmetrically arranged on two sides. The construction method comprises the following construction steps:

(1) paying off and positioning: and (5) measuring and setting out, excavating a foundation trench, and determining the pile position of the rectangular pile.

(2) And (3) guide wall construction: and constructing the cast-in-place concrete guide wall 1 along two sides of the longitudinal axis of the pile position of the rectangular pile.

(3) Mounting the prefabricated first positioning guide plate 45: first arc-shaped protruding blocks 46 which are engaged with the first arc-shaped grooves 4 of the parallel adjacent rectangular piles 2 and can slide mutually are arranged on one side of the first positioning guide plate 45, the rest shapes and sizes of the first positioning guide plate 45 are the same as the cross section shapes and sizes of the rectangular piles 2, embedded steel on the first positioning guide plate 45 is welded with embedded steel at the bottom end of the lower-section rectangular pile 9, a second central circular hole 44 of the first positioning guide plate 45 is aligned with a first central circular hole 3 of the lower-section rectangular pile 9, and a second arc-shaped groove 42 of the first positioning guide plate 45 is aligned with the first arc-shaped groove 4 of the lower-section rectangular pile 9.

(4) Hoisting the lower section of rectangular pile in place: and hoisting the bundled lower-section rectangular pile 9 above the pile position by using a crawler crane through a steel wire rope, and placing the lower-section rectangular pile 9 in the hydraulic clamp 18 and the rectangular pile positioning guide hole 33 of the second positioning guide plate 32 of the positioning guide frame 36.

(5) Fixing the lower section of rectangular pile: starting a hydraulic clamp 18, clamping and fixing a lower-section rectangular pile 9, fixing the hydraulic clamp 18 with the bottom of a lower power head 16, namely a vibratory hammer, of a long-spiral double-power-head pile driver 11 through a flange assembly 20, and slidably fitting the hydraulic clamp on a plurality of upright guide rails 27 fixed with a main mast 10 of the long-spiral double-power-head pile driver 11, wherein two clamping plates, namely two clamping plates 22 of the hydraulic clamp 18 are respectively provided with a second arc-shaped bump 24 which is matched with first arc-shaped grooves 4 on two sides of the lower-section rectangular pile 9 so that the axial line of a first central circular hole 3 of the lower-section rectangular pile 9 and the central lines of an upper power head 14 and a lower power head 16 of the long-spiral double-power-head pile driver 11 are positioned on the same vertical line; unhooking the crane, correcting the verticality of the lower section rectangular pile 9, sliding the lower power head 16, namely a vibration hammer downwards, and pressing the bottom end of a lower flange 49 in a flange assembly 20 at the lower end of the lower power head 16 against the top end of the lower section rectangular pile 9;

(6) positioning a drill rod: a spiral drill rod 15 which is installed in an upper power head 14 of the long-spiral double-power-head pile driver 11 and is 35-40 m long penetrates through an upper power head 16, namely a vibration hammer, is inserted into a first central circular hole 3 of the lower-section rectangular pile 9 and extends out of the lower end of the lower-section rectangular pile 9.

(7) Positioning by a positioning guide frame: and tightly inserting the central hole positioning pipe 35 into the third central circular hole 38 of the third positioning guide plate 37 and the first central circular hole 3 of the upper section rectangular pile 6 which is adjacent in parallel, and correcting the verticality of the central hole positioning pipe 35. The left side of the third positioning guide plate 37 is provided with an arc-shaped notch 34 for the first arc-shaped projection 46 of the first positioning guide plate 45 to slide downwards. And adjusting and enabling the plurality of limiting rollers 31 on the second positioning guide plate 32 to tightly abut against the front side and the rear side of the lower rectangular pile 9, wherein at the moment, the first ball 30 arranged on the left side of the positioning guide frame 36 is matched and tightly abutted against the first arc-shaped groove 4 on the left side of the lower rectangular pile 9, and the first arc-shaped bump 46 of the first positioning guide plate 45 at the lower end of the right side of the lower rectangular pile 9 is matched and tightly abutted against the first arc-shaped groove 4 of the adjacent rectangular piles 2.

(8) Construction by a middle digging method: the hydraulic fixture 18 is loosened, the upper power head 14 drives the spiral drill rod 15 to rotate reversely to open the reaming drill bit 19 and take soil, meanwhile, the lower power head 16 presses the lower section rectangular pile 9 downwards, the drill rod and the lower section rectangular pile 9 sink synchronously, the front side and the rear side of the lower section rectangular pile 9 are in rolling fit with the limiting idler wheel 31 all the time in the sinking process, the first arc-shaped groove 4 on the left side of the lower section rectangular pile 9 is in rolling fit with the first ball 30 all the time, and the first arc-shaped bump 46 of the first positioning guide plate 45 on the lower end of the right side of the lower section rectangular pile 9 is in sliding fit with the first arc-shaped groove 4 of the parallel adjacent rectangular pile 2 all the time, so that the positioning precision and the verticality of the lower section rectangular pile 9 are guaranteed until the lower section rectangular pile 9 sinks to a preset position. It should be understood that the predetermined position of the lower rectangular pile 9 refers to a predetermined position for the first time, that is, a predetermined position at this time which is the same as the upper and lower positions of the adjacent upper rectangular pile 6, rather than a final predetermined position to which the lower rectangular pile 9 sinks after being welded to the upper rectangular pile 6.

(9) Resetting the upper power head and the lower power head: the power head 14 is rotated and lifted up to make the bottom end of the auger 15 have the length of the upper section of rectangular pile 6, and the upper power head 16, namely the vibration hammer drives the lower flange 49 in the flange assembly 20 to be separated from the lower section of rectangular pile 9 and lifted up to the initial position. Here, the following described swivel is well understood: means that the rotation direction of the upper power head 14 and the auger stem 15 is opposite to the rotation direction in the step (8).

(10) Positioning the upper section rectangular pile: and (5) repeating the steps (4) to (7) except that the object is converted from the lower-section rectangular pile 9 to the upper-section rectangular pile 6. Namely:

hoisting the upper section rectangular pile 6 in place: and hoisting the bundled upper rectangular pile 6 above the pile position by using a crawler crane through a steel wire rope, and placing the upper rectangular pile 6 in the hydraulic clamp 18 and the rectangular pile positioning guide hole 33 of the second positioning guide plate 32 of the positioning guide frame 36.

Fixing the upper section of rectangular pile: the hydraulic clamp 18 is started to clamp and fix the upper section rectangular pile 6, the hydraulic clamp 18 is fixed with the bottom of a lower power head 16, namely a vibratory hammer, of the long spiral double-power-head pile driver 11 through a flange assembly 20 and is in sliding fit with a plurality of upright guide rails 27 fixed with a main mast 10 of the long spiral double-power-head pile driver 11, and two clamping plates 22 of the hydraulic clamp 18 are respectively provided with a second arc-shaped protruding block 24 which is matched with first arc-shaped grooves 4 on two sides of the upper section rectangular pile 6 so that the axial line of a first central circular hole 3 of the upper section rectangular pile 6 and the central lines of an upper power head 14 and a lower power head 16 of the long spiral double-power-head pile driver 11 are on the same vertical line. And unhooking the crane, correcting the verticality of the lower section rectangular pile 9, sliding the lower power head 16, namely the vibration hammer downwards, and pressing the bottom end of a lower flange 49 in a flange assembly 20 at the lower end of the lower power head 16 against the top end of the lower section rectangular pile 9.

Positioning a drill rod: a spiral drill rod 15 which is installed in an upper power head 14 of a long spiral double-power-head pile driver 11 and is 35-40 m long penetrates through a lower power head 16, namely a vibrating hammer, and is inserted into a first center circular hole 3 of an upper section rectangular pile 6.

Positioning by a positioning guide frame: and tightly inserting the central hole positioning pipe 35 into the third central circular hole 38 of the third positioning guide plate 37 and the first central circular hole 3 of the upper section rectangular pile 6 which is adjacent in parallel, and correcting the verticality of the central hole positioning pipe 35. The left side of the third positioning guide plate 37 is provided with an arc-shaped notch 34 for the first arc-shaped projection 46 of the first positioning guide plate 45 to slide downwards. And adjusting and enabling the plurality of limiting rollers 31 on the second positioning guide plate 32 to abut against the front side and the rear side of the upper section rectangular pile 6, wherein at the moment, the first ball 30 arranged on the left side of the positioning guide frame 36 is inosculated and abuts against the first arc-shaped groove 4 on the left side of the upper section rectangular pile 6, and the first arc-shaped bump 46 of the first positioning guide plate 45 at the lower end of the right side of the upper section rectangular pile 6 is inosculated and abuts against the first arc-shaped groove 4 of the adjacent parallel rectangular piles 2.

The perpendicularity of the center hole positioning pipe 35 in the above step 7) and step 10) is corrected, and it is also possible to simultaneously correct the levelness of the second guide plate top face and the third guide plate top face to correct the vertical face of the hole wall of the rectangular pile positioning guide hole 33 because the hole wall is perpendicular to the top face as described below.

(11) Pile splicing: and after aligning the upper section rectangular pile 6 with the lower section rectangular pile 9 and correcting the verticality, welding the peripheries of the embedded steel edges of the butt joint of the upper and lower rectangular piles below the second positioning guide plate 32.

(12) And (5) repeating the step (8), except that the object is converted into the upper section rectangular pile 6 from the lower section rectangular pile 9, and the spiral drill rod 15 penetrates through the upper section rectangular pile and the lower section rectangular pile and extends out of the bottom end of the lower section rectangular pile 9 until the upper section rectangular pile 6 and the lower section rectangular pile 9 which is butted with each other are sunk to a preset position. Repeating the step (9), so that the upper power head and the lower power head are reset, and the bottom end of the spiral drill rod 15 is empty for the length of a lower section of rectangular pile 9; namely:

construction by a middle digging method: the upper power head 14 drives the spiral drill rod 15 to penetrate through the upper section rectangular pile and the lower section rectangular pile and extend out of the bottom end of the lower section rectangular pile 9; the hydraulic clamp 18 is released, the upper power head 14 drives the auger stem 15 to rotate in the reverse direction to open the reamer bit 19 and remove the earth, meanwhile, the lower power head 16 presses the upper section rectangular pile 6 downwards, the auger stem 15, the upper section rectangular pile 6 and the lower section rectangular pile 9 welded with the upper section rectangular pile 6 sink synchronously, the front side and the rear side of the upper section rectangular pile 6 are in rolling fit with the limiting roller 31 all the time in the sinking process, the first arc-shaped groove 4 on the left side of the upper section rectangular pile 6 is in rolling fit with the first ball 30 all the time, the first arc-shaped bump 46 of the first positioning guide plate 45 at the lower end of the right side of the upper section rectangular pile 6 is in sliding fit with the first arc-shaped groove 4 of the parallel adjacent rectangular pile 2 all the time, therefore, the positioning accuracy and the verticality of the upper rectangular pile 6 and the lower rectangular pile 9 welded with the upper rectangular pile 6 are ensured until the upper rectangular pile 6 and the lower rectangular pile 9 welded with the upper rectangular pile 6 sink to a preset position.

Resetting the upper power head and the lower power head: the lower power head 16, namely the vibration hammer drives the lower flange 49 in the flange assembly 20 to be separated from the upper rectangular pile 6 and lift up to the initial position.

The length of the upper rectangular pile 6 and the length of the lower rectangular pile 9 are described above for the sake of description consistent with the description of the rectangular piles mentioned in this paragraph, and it is understood that the lengths of the upper rectangular pile 6 and the lower rectangular pile 9 are equal, for example, 10 meters. The same applies to the above directly by the length of one rectangular pile 2.

(13) And (4) repeating the steps (3) to (12) repeatedly until an underground continuous wall formed by the chain concrete precast piles is formed, and forming the elliptical water stop holes 5 by the two first arc-shaped grooves 4 which are adjacent in parallel.

(14) Grouting to the water stop hole: and grouting a water stop hole 5 formed after two adjacent first arc-shaped grooves 4 are tightly attached by using a pressure grouting machine until the orifice is overflowed and solidified to play a waterproof role.

The construction method also comprises the construction steps of transporting the earthwork vehicle generated by reaming and pile sinking by adopting equipment such as an excavator and the like.

The installation of the positioning guide plate 45 may be specifically performed, that is, the positioning guide plate 45 may not be installed on the first lower pile 9 in each row, because it is understood that the first rectangular pile 2 in each row does not need to adopt the construction method of the present invention, but adopts the middle digging method in the prior art for construction, that is, the first rectangular pile 2 does not need the first positioning guide plate 45 and the positioning guide frame 36, and the hole expansion and the pile sinking are directly performed and synchronized, and certainly the detection is performed to ensure the verticality of the rectangular pile 2.

The perpendicularity of the rectangular pile 2 can be corrected by adopting two theodolites to detect the perpendicularity of the rectangular pile 2 in two different directions.

The rectangular pile 2 is sunk to a preset position, and the rectangular pile 2 can also be understood as sinking to a designed elevation, for example, the pile top is about 1 meter higher than the top surface of the guide wall 1.

The embedded steel of the first positioning guide plate 45 generally adopts angle steel 43. The embedded steel of the rectangular pile 2 generally refers to end plates, such as the lower end plate 7 of the upper section of rectangular pile and the upper end plate 8 of the lower section of rectangular pile.

The reamer bit 19 is a prior art bit which can be expanded to ream and furled to pass through the first central circular hole 3 of the rectangular pile 2 under the hydraulic control of the host machine. In the above-mentioned construction process, after the upper power head 14 drives the auger stem 15 to pass through the first central circular hole 3 of the rectangular pile 2 and the second central circular hole 44 of the first positioning guide plate 45, the hole expanding drill bit 19 is expanded, and the diameter of the expanded hole after the drill bit is expanded is equal to or larger than the long side of the rectangular pile 2.

In the above-mentioned middle digging method construction, the upper power head 14 drives the auger stem 15 to move down 1 meter ahead, and simultaneously drives the lower power head 16, i.e. the vibration hammer to press down, so that the rectangular pile 2 sinks synchronously with the taking of soil by the auger stem 15.

The first ball 30, which is engaged with the first arc-shaped groove 4 and rolls to slide the rectangular pile 2 downward, may have the following structure: the left side of the second positioning guide plate 32 is provided with a groove for the first ball 30 to roll, one side of the groove close to the rectangular pile positioning guide hole 33 is provided with a notch, the diameter size of the first ball 30 is larger than the transverse depth size of the groove, namely, part of the spherical surface of the first ball 30 protrudes out of the left side, so that the first ball 30 is always in rolling contact with the first arc-shaped groove 4 of the downslide rectangular pile 2, and the notch can be provided with a limiting device for preventing the first ball 30 from being separated from the groove, for example, a limiting ring with the inner diameter smaller than the diameter of the first ball is welded.

The first and second

arcuate projections

46, 24 described above may also be referred to as plate ribs.

As shown in fig. 3, the long-spiral double-power-head pile driver 11 includes a main machine 12, a main mast 10 fixed to the main machine 12, an upper power head 14 slidably connected to the main mast 10, connected to a winch on the main machine via a first wire rope 13, and configured to clamp a 35-40 m-long spiral drill pipe 15 and drive it to rotate, a lower power head 16, i.e., a vibration hammer, slidably connected to the main mast 10, connected to another winch on the main machine 12 via a second wire rope 17, and configured to press down a rectangular pile 2, and a hydraulic clamp 18 slidably connected to the main mast 10, fixed to the lower power head 16, i.e., the vibration hammer, via a flange assembly 20, and configured to clamp the rectangular pile 2, wherein a reamer bit 19 is disposed on an end of the spiral drill pipe 15 extending out of a bottom end of the rectangular pile 2 through the lower power head 16, i.e., the vibration hammer, and a first central circular hole 3 of the rectangular pile 2. The above main machine 12 can adopt a crawler-type pile machine main machine. The upper power head 14 described above and driven in rotation is of course referred to as the auger stem 15.

As shown in fig. 3, 4, 5, 6, and 7, the hydraulic clamp 18 includes a fixing frame 29, two clamping cylinders 23 symmetrically installed on two sides of the fixing frame 29, and clamping plates 22 fixed on free ends of piston rods of the respective clamping cylinders, each clamping plate 22 has a second arc-shaped protrusion 24 matching with the first arc-shaped groove 4 on two sides of the rectangular pile 2 so that an axis of the first central circular hole 3 of the rectangular pile 2 and a center line of the upper and lower power heads are on the same vertical line, the same ends of the two clamping plates 22 are roll-fitted on the guide rail 21 of the fixing frame 29 through respective second balls 25, the fixing frame 29 is fixed with the lower power head 16 through a flange assembly 20, and the fixing frame 29 has a hoop 28 for sliding-fitting with a plurality of upright guide rails 27 fixed on the main mast 10. The connecting part of the hoop 28 and the two upright guide rails 27 is provided with a circular sliding sleeve or an annular sliding sleeve 26 of 1/2-2/3 circles, which are respectively sleeved and matched with the upright guide rails 27 in a sliding way. It will be understood that the components of the hydraulic clamp 18 are all made of steel.

The flange assembly 20 includes a connecting member 50 or connecting rod, and a plurality of connecting members or connecting rods may be disposed above and below the connecting member. The flange plate is divided into an upper flange plate 48 and a lower flange plate 49, a plurality of bolt holes corresponding to each other are arranged on the upper flange plate and the lower flange plate along the circumference, and the flange plates are fastened by a plurality of connecting bolts 51: a plurality of bolts are respectively inserted into the bolt holes and are locked by respective nuts, or the bolts penetrate through the through holes of the upper flange plate and then are screwed in the threaded holes of the lower flange plate. It will be understood that the upper ends of the plurality of upper connectors are welded to the lower power head 16, and the lower ends of the plurality of lower connectors are welded to the upper flange 48; the upper ends of the plurality of lower connecting pieces are welded to the lower flange 49, and the lower ends of the plurality of lower connecting pieces are welded to the fixing frame 29.

As shown in fig. 8:

the positioning guide frame 36 comprises a rectangular steel frame 41, height adjusting devices 40 are arranged on four legs of the rectangular steel frame 41, a second positioning guide plate 32 and a third positioning guide plate 33 are arranged at the top of the positioning guide frame 36, a rectangular pile positioning guide hole 33 is arranged on the second positioning guide plate 32, the second positioning guide plate 32 at the left side of the rectangular pile positioning guide hole 33 is provided with a first ball which is used for matching with the first arc-shaped groove 4 at the left side of the rectangular pile 2 and rolling to enable the rectangular pile 2 to slide downwards, a plurality of limiting rollers 31 which are used for tightly abutting against the front side and the back side of the rectangular pile 2 and rolling to enable the rectangular pile 2 to slide downwards are symmetrically arranged on the second positioning guide plate 32 at the front side and the rear side of the rectangular pile positioning guide hole 36, a central hole notch 34 through which a first arc-shaped lug 46 of the first positioning guide plate 45 can slide downwards is arranged at the left side of the third positioning guide plate 37, and a central hole notch 34 through which a positioning pipe 35 can pass and be inserted into a first sunken rectangular pile 2 A third center round hole 38 in the center round hole 3, the distance between the center perpendicular of the third center round hole 38 and the center perpendicular of the rectangular pile positioning guide hole 33 is equal to the distance between the center perpendicular of the center holes of two adjacent parallel rectangular piles 2, the top surface of the second positioning guide plate 32 and the top surface of the third positioning guide plate 37 are on the same plane, the top surface of the second positioning guide plate 32 and the hole wall of the rectangular pile positioning guide hole 33 are perpendicular to each other, and the top surface of the third positioning guide plate 37 and the hole wall of the third center round hole 38 are perpendicular to each other.

The steel can be made into a rectangular frame 41 by using section steel, and the second positioning guide plate 32 and the third positioning guide plate 37 made of steel plates are fixed in the section steel frame at the tops of the four legs by welding.

The positioning guide 36 may further include means for aligning the levelness of the top surface of the second positioning guide plate 32 with the top surface of the third positioning guide plate 37: the top surface of the lower beam of the rectangular frame 41 is parallel to the top surface of the second positioning guide plate 32 and the top surface of the third positioning guide plate 37, and a level gauge 39 for leveling the levelness of the top surface of the lower beam is arranged on the lower beam. Such as a bubble locator or the like, for example.

The perpendicularity of the correction center hole positioning tube 35 can be directly corrected by adopting a theodolite. The levelness of the top surfaces of the second positioning guide plate 32 and the third positioning guide plate 37 can also be adjusted by utilizing the property that the hole wall is vertical to the top surface of the plate, the levelers 39 can be directly placed on the top surfaces of the second positioning guide plate 32 and the third positioning guide plate 37 for adjustment, or the levelers 39 arranged on the top surfaces of the lower beams parallel to the top surfaces of the second positioning guide plate 32 and the third positioning guide plate 37 can be used for adjustment, so that the verticality of the central hole positioning tube 35 and the verticality of the hole wall of the rectangular pile positioning guide hole 33 can be indirectly corrected.

The height adjustment means 20 on each leg is preferably configured as: the bottom of each leg is provided with a lower convex cylinder, a rotating sleeve is sleeved on the cylinder, the cylinder and the rotating sleeve are provided with a structure for limiting the axial positions of the cylinder and the rotating sleeve, the middle lower section of the rotating sleeve is provided with a threaded hole, and the threaded hole is screwed with a screw rod with a base plate to adjust the height position of each leg. The structure for limiting the axial separation of the cylinder and the sleeve is characterized in that an annular groove is arranged on the cylinder, and the front end of a limiting screw transversely screwed in a threaded hole in the side wall of the sleeve is embedded in the annular groove, so that the sleeve can rotate, the cylinder and the sleeve cannot axially move, and the axial separation cannot occur.

It is understood that the limiting of the limiting roller 31 refers to transverse or horizontal limiting, and the roller is used for vertical rolling. The number of the limiting rollers 31 can be eight, four second positioning guide plates 32 are arranged on the front side of the rectangular pile positioning guide hole 33, and four second positioning guide plates 32 are arranged on the rear side of the rectangular pile positioning guide hole 33; the structure of each limit roller 31 may be: the axis of the roller shaft is parallel to the front and the back of the rectangular guide hole, two ends of the roller shaft are rotatably matched on a second positioning guide plate at the front side or the back side of the rectangular pile positioning guide hole, two rollers on each roller shaft are accommodated in a notch of the second positioning guide plate, the opening of the second positioning guide plate faces the rectangular guide hole, elongated slots for the roller shaft to move back and forth are formed in the second positioning guide plates at two ends of the notch, and the front outer side and the back outer side of the second positioning guide plate are provided with adjusting screw and nut devices for adjusting the front and back positions of the roller shaft so that the roller is tightly pressed against the front side face or the back side face of the rectangular pile to roll or separate from the front side face or the back side face of the rectangular pile. The specific structure of the adjusting screw nut device can be as follows: the roller shaft between every two rollers is provided with an adjusting sleeve with internal threads, each adjusting sleeve is internally screwed with an adjusting screw rod, the adjusting screw rods are simultaneously screwed in the threaded holes of the outer side plates at the top end of the section steel frame and extend outwards from the outer side plates, the end parts of the adjusting screw rods are provided with structures for adjustment, for example, a linear groove for linear screwdriver insertion, and a nut fastened relative to the outer side plates can also be arranged on the threaded rods.

As shown in fig. 1, 4, 5, 6, 7, 8, 9, 10, the first arc-shaped grooves 4 of each side of each rectangular pile 2 are preferably two. Two first arc-shaped protrusions 46 are arranged on one side of each first positioning guide plate 45. The second arcuate projections 24 on each clamp plate 22 of the hydraulic clamp 18 are two. The number of the column guides 27 fixed to the main mast 10 is preferably two. The number of the first balls 30 mounted on the left side of the positioning guide 36 is two. The number of the arc-shaped notches 34 on the left side of the third positioning guide plate 37 is two.

As shown in fig. 9 and 10, the first positioning guide plate 45 preferably has: the plate body is a rectangular plate body 47 with the same shape and size as the cross section of the rectangular pile 2, the center of the rectangular plate body 47 is provided with a second central round hole 44, the diameter of which is equal to that of the first central round hole 3 of the rectangular pile 2, and the axis of the hole is on the same vertical line with that of the first central round hole 3 of the rectangular pile 2, one side of the first positioning guide plate 45 is provided with a first arc-shaped bump 46 which is inosculated with the first arc-shaped groove 4 of the adjacent rectangular pile 2 and can slide mutually, and the other side of the first positioning guide plate 45 is provided with a second arc-shaped groove 42, the shape and size of which are the same as that of the first arc-shaped groove 4 of the rectangular pile 2, and the arc surface of which is on the same vertical plane; the first positioning guide plate 45 is a concrete prefabricated part, and angle steel 43 used for being welded with embedded steel at the bottom end of the rectangular pile 2 is embedded in the top end of the first positioning guide plate. The thickness of the rectangular plate body of the first positioning guide plate 45 may be greater than 250 mm.

As is common knowledge, the rectangular pile 2 is a pile having a rectangular cross section or a square cross section.

The juxtaposition of adjacent elements as described above may also be referred to as parallel adjacent. The front, rear, left and right sides, etc. are mentioned above for convenience of description, and should not be construed as limiting the scope of protection, such as the front, rear, left and right directions are just opposite if the underground diaphragm wall is constructed from left to right. For another example, if the rectangular pile is used, the left side may be called the left end or one end, and the right side may be called the right end or the other end.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Adopt chain precast concrete pile to constitute underground continuous wall's construction method, chain precast concrete pile be equipped with first central round hole, bilateral symmetry be equipped with the rectangle stake of first arc recess, its characterized in that: the method comprises the following construction steps:

(3) installing a prefabricated first positioning guide plate: a first arc-shaped projection which is engaged with and can slide with a first arc-shaped groove of a parallel adjacent rectangular pile is arranged on one side of the first positioning guide plate, the other shapes and sizes of the first positioning guide plate are the same as the shapes and sizes of the cross sections of the rectangular piles, pre-buried steel on the first positioning guide plate is welded with pre-buried steel at the bottom end of a lower-section rectangular pile, a second central circular hole of the first positioning guide plate is aligned with a first central circular hole of the lower-section rectangular pile, and a second arc-shaped groove of the first positioning guide plate is aligned with a first arc-shaped groove of the lower-section rectangular pile;

(5) fixing the lower section of rectangular pile: starting a hydraulic clamp, clamping and fixing a lower-section rectangular pile, fixing the hydraulic clamp with the bottom of a lower power head, namely a vibration hammer, of a long-spiral double-power-head pile machine through a flange assembly, and slidably fitting the hydraulic clamp on a plurality of upright guide rails fixed with a main mast of the long-spiral double-power-head pile machine, wherein two clamping plates of the hydraulic clamp are respectively provided with a second arc-shaped lug which is matched with first arc-shaped grooves on two sides of the lower-section rectangular pile so that the axis of a first central circular hole of the lower-section rectangular pile and the central lines of an upper power head and a lower power head of the long-spiral double-power-head pile machine are positioned on the same vertical line; unhooking the crane, correcting the verticality of the lower section rectangular pile, sliding the lower power head downwards, and pressing the bottom end of the lower flange plate against the top end of the lower section rectangular pile;

(6) positioning a drill rod: a spiral drill rod which is arranged in an upper power head of the long-spiral double-power-head pile driver and has the length of 35-40 meters penetrates through the vibration hammer, is inserted into a first central circular hole of the lower section of rectangular pile and extends out of the lower end of the lower section of rectangular pile;

(7) positioning by a positioning guide frame: inserting a central hole positioning pipe into a third central circular hole of a third positioning guide plate and a first central circular hole of an upper section rectangular pile which is adjacent in parallel, and correcting the verticality of the central hole positioning pipe; an arc-shaped notch for the first arc-shaped bump of the first positioning guide plate to slide downwards is formed in the left side of the third positioning guide plate; adjusting and enabling a plurality of limiting idler wheels on the second positioning guide plate to tightly abut against the front side surface and the rear side surface of the lower rectangular pile, enabling a first ball arranged on the left side of the positioning guide frame to be matched and tightly abutted in a first arc-shaped groove on the left side of the lower rectangular pile, and enabling a first arc-shaped bump of a first positioning guide plate on the lower end of the right side of the lower rectangular pile to be matched and tightly abutted in a first arc-shaped groove of the adjacent rectangular piles;

(12) repeating the step (8), except that the object is converted into an upper section rectangular pile from a lower section rectangular pile, and the spiral drill rod penetrates through the upper section rectangular pile and the lower section rectangular pile and extends out of the bottom end of the lower section rectangular pile until the upper section rectangular pile (6) and the lower section rectangular pile (9) which are butted sink to a preset position; repeating the step (9), so that the upper power head and the lower power head are reset, and the bottom end of the spiral drill rod is empty for the length of a lower section of rectangular pile;

(14) grouting to the water stop hole: grouting a water stop hole formed by closely attaching the adjacent first arc-shaped grooves by using a pressure grouting machine until the hole opening is flooded and solidified to play a waterproof role;

the positioning guide frame comprises a rectangular frame made of steel, height adjusting devices are arranged on four legs of the rectangular frame, a second positioning guide plate and a third positioning guide plate are arranged at the top of the positioning guide frame, a rectangular pile positioning guide hole is formed in the second positioning guide plate, a first ball is arranged on the second positioning guide plate on the left side of the rectangular pile positioning guide hole and used for being engaged with and rolling along a first arc-shaped groove on the left side of the rectangular pile so that the rectangular pile can slide downwards, a plurality of limiting rollers used for abutting against the front side surface and the rear side surface of the rectangular pile and rolling so that the rectangular pile can slide downwards are symmetrically arranged on the second positioning guide plate on the front side and the rear side of the rectangular pile positioning guide hole, an arc-shaped notch for the first arc-shaped lug of the first positioning guide plate to slide downwards is formed in the left side of the third positioning guide plate, a third center of the third positioning guide plate is formed for a positioning pipe to pass through and be inserted into a first center round hole of an adjacent rectangular pile with a sunken center hole, the distance between the center vertical line of the third center circular hole and the center vertical line of the rectangular pile positioning guide hole is equal to the distance between the center vertical lines of the center holes of the two parallel adjacent rectangular piles;

the long-spiral double-power-head pile machine comprises a main machine, a main mast fixed with the main machine, an upper power head which is connected to the main mast in a sliding manner, is connected with a winch on the main machine through a first steel wire rope and is used for clamping a spiral drill rod with the length of 35-40 meters and driving the spiral drill rod to rotate, a lower power head which is a vibration hammer and is connected to the main mast in a sliding manner, is connected with another winch on the main machine through a second steel wire rope and is used for pressing down a rectangular pile, and a hydraulic clamp which is connected to the main mast in a sliding manner, is fixed on the lower power head through a flange assembly and is used for clamping the rectangular pile, wherein a reaming bit is arranged on the end part of the spiral drill rod, which penetrates through the lower power head and a first central circular hole of the rectangular pile, and extends out of the bottom end of the rectangular pile;

the hydraulic fixture comprises a fixing frame, two clamping oil cylinders symmetrically arranged on two sides of the fixing frame, and clamping plates fixed at free ends of piston rods of the respective clamping oil cylinders, wherein each clamping plate is provided with a second arc-shaped convex block which is matched with first arc-shaped grooves on two sides of a rectangular pile so that the axis of a first central circular hole of the rectangular pile and the central lines of an upper power head and a lower power head are on the same vertical line;

the structure of the first positioning guide plate is as follows: the plate body is a rectangular plate body with the same shape and size as the cross section of the rectangular pile, the center of the rectangular plate body is provided with a second central round hole with the diameter equal to that of a first central round hole of the rectangular pile and the axis of the hole and the axis of the first central round hole of the rectangular pile on the same vertical line, one side of the first positioning guide plate is provided with a first arc-shaped lug which is inosculated with and can slide with a first arc-shaped groove of the adjacent rectangular pile, and the other side of the first positioning guide plate is provided with a second arc-shaped groove which is the same in shape and size as the first arc-shaped groove of the rectangular pile and has an arc surface on the same vertical plane; the first positioning guide plate is a concrete prefabricated part, and angle steel used for being welded with embedded steel at the bottom end of the rectangular pile is embedded in the top end of the first positioning guide plate.

2. The construction method according to claim 1, characterized in that: the number of the upright post guide rails is two.

3. The construction method according to claim 1, characterized in that: the top surface of the second positioning guide plate and the top surface of the third positioning guide plate are on the same plane, the top surface of the second positioning guide plate is perpendicular to the hole wall of the rectangular pile positioning guide hole, and the top surface of the third positioning guide plate is perpendicular to the hole wall of the third central circular hole; the positioning guide frame further comprises a device for adjusting the levelness of the top surface of the second positioning guide plate and the top surface of the third positioning guide plate: the top surface of the lower beam of the rectangular frame is parallel to the top surfaces of the second positioning guide plate and the third positioning guide plate, and a level gauge for leveling the levelness of the top surface of the lower beam is arranged on the lower beam.

4. The construction method according to claim 1, characterized in that: the structure of the height adjusting device on each leg is as follows: the bottom of each leg is provided with a lower convex cylinder, a rotating sleeve is sleeved on the cylinder, the cylinder and the rotating sleeve are provided with a structure for limiting the axial positions of the cylinder and the rotating sleeve, the middle lower section of the rotating sleeve is provided with a threaded hole, and the threaded hole is screwed with a screw rod with a base plate to adjust the height position of each leg.

5. The construction method according to claim 1, characterized in that: the number of the limiting idler wheels is eight, four second positioning guide plates are arranged on the front side of the rectangular pile positioning guide hole, and four second positioning guide plates are arranged on the rear side of the rectangular pile positioning guide hole; the structure of each limiting roller is as follows: the axis of the roller shaft is parallel to the front and the back of the rectangular guide hole, two ends of the roller shaft are rotatably matched on a second positioning guide plate on the front side or the back side of the rectangular pile positioning guide hole, two rollers on each roller shaft are accommodated in a notch of the second positioning guide plate, the opening of the second positioning guide plate faces the rectangular guide hole, elongated slots for the roller shaft to move back and forth are formed in the second positioning guide plates on two ends of the notch, and the front outer side and the back outer side of the second positioning guide plate are provided with adjusting screw and nut devices for adjusting the front and back positions of the roller shaft so that the roller can be tightly pressed against the front side face or the back side face of the rectangular pile to roll or separate from the front side face or the back side face of the rectangular pile.

6. The construction method according to claim 1, characterized in that: two first arc-shaped grooves are formed in each side of each rectangular pile; two first arc-shaped convex blocks are arranged on one side of each first positioning guide plate; two second arc-shaped convex blocks are arranged on each clamping plate of the hydraulic clamp; two upright post guide rails are fixed on the main mast; two first balls are arranged on the left side of the positioning guide frame; the number of the arc-shaped notches on the left side of the third positioning guide plate is two.