CN114108611A - Construction method of large-diameter steel pipe concrete reducing pile foundation - Google Patents
Construction method of large-diameter steel pipe concrete reducing pile foundation Download PDFInfo
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- CN114108611A CN114108611A CN202111349768.6A CN202111349768A CN114108611A CN 114108611 A CN114108611 A CN 114108611A CN 202111349768 A CN202111349768 A CN 202111349768A CN 114108611 A CN114108611 A CN 114108611A
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/22—Piles
- E02D5/34—Concrete or concrete-like piles cast in position ; Apparatus for making same
- E02D5/38—Concrete or concrete-like piles cast in position ; Apparatus for making same making by use of mould-pipes or other moulds
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D13/00—Accessories for placing or removing piles or bulkheads, e.g. noise attenuating chambers
- E02D13/08—Removing obstacles
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/22—Piles
- E02D5/48—Piles varying in construction along their length, i.e. along the body between head and shoe, e.g. made of different materials along their length
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/66—Mould-pipes or other moulds
- E02D5/665—Mould-pipes or other moulds for making piles
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B11/00—Other drilling tools
- E21B11/04—Boring grabs
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/28—Enlarging drilled holes, e.g. by counterboring
Abstract
The application relates to a construction method of a large-diameter steel pipe concrete variable-diameter pile foundation, which adopts equal-diameter drilling of upper pile holes in sequence, wherein each time the upper pile hole is drilled to a set depth, a high steel pipe pile is connected; reaming and drilling a middle pile hole, wherein the middle pile hole is positioned at the bottom of the upper pile hole and in a rock stratum, and a drilling machine adopts a drilling bucket with the diameter sequentially increased for reaming and drilling in a grading manner from inside to outside; and (3) blasting and removing slag in the lower pile hole, wherein the lower pile hole is positioned at the bottom of the middle pile hole and in the bedrock, a plurality of blasting holes are drilled downwards in the bottom of the middle pile hole, explosives are buried in the blasting holes and are subjected to loosening blasting, and a drilling machine drills holes and removes slag until the set hole depth is reached. According to the construction method, the upper pile hole is drilled in an equal diameter mode in sequence according to the geological conditions that the upper part of the pile hole is soft and the lower part of the pile hole is hard, the middle pile hole is reamed and drilled, the lower pile hole is blasted and slag is removed to conduct step-by-step drilling construction, the utilization rate of a drilling machine is improved, the hole forming efficiency of the pile hole is improved, and the construction cost of a pile foundation is reduced.
Description
Technical Field
The application relates to the technical field of bridge foundation construction, in particular to a construction method of a large-diameter concrete-filled steel tube variable-diameter pile foundation.
Background
With the continuous development of railways, expressways and urban high-rise buildings, the diameter and the depth of a pile foundation are larger and larger due to the continuous improvement of the requirement on the bearing capacity of the pile foundation, and the bottom of the pile foundation generally enters a middle weathered rock stratum, and some of the pile foundations even enter a slightly weathered rock stratum. The large-caliber embedded rock bored pile becomes the preferred type of foundation engineering and is increasingly applied to production. How to ensure the engineering quality and progress of the large-caliber embedded rock drilling cast-in-place pile and control the cost in the construction becomes a problem which must be faced by the construction of the large-caliber embedded rock drilling cast-in-place pile.
In the construction process of the cast-in-situ bored pile, the rotary drilling rig has high hole forming rate. The novel drilling equipment with the advantages of small aperture deviation, quick and flexible movement and the like is being increasingly adopted in the construction of cast-in-situ bored piles, and has the tendency of gradually replacing the traditional forward and reverse circulation drilling machines and punching pile machines.
In the current construction of the bored pile, after the pile foundation enters a hard rock stratum, the rotary drilling rig can continue to drill in the rock stratum after the rock-entering drill bit is replaced, but the drilling speed of the rotary drilling rig is obviously lower than that of the rotary drilling rig in a soil layer and a strongly weathered rock stratum. In actual construction, although the construction efficiency of the rotary drilling rig is obviously higher than that of a traditional forward and reverse circulation drilling rig and a traditional punching pile machine, the construction cost of the rotary drilling rig is high, if the pile foundation construction enters a rock entering stage, particularly under the condition of large rock entering depth, the construction efficiency of the rotary drilling rig is obviously reduced, and the loss of a drilling tool of a rock entering construction team is increased, so that the construction cost of the rotary drilling rig in the rock entering stage is obviously increased.
Disclosure of Invention
The embodiment of the application provides a construction method for a large-diameter concrete-filled steel tube variable-diameter pile foundation, and aims to solve the problem that in the related art, a rotary drilling rig has a low drilling speed after entering a hard rock stratum, so that the construction cost of the rotary drilling rig in a rock entering stage is remarkably increased.
The embodiment of the application provides a construction method of a large-diameter steel pipe concrete reducing pile foundation, which comprises the following steps:
drilling an upper pile hole in an equal diameter mode, embedding a steel casing after measuring the center point of the pile hole in a construction site, backfilling with clay and tamping, aligning a drilling bucket in the equal diameter mode with the upper pile hole with the center of the steel casing after a drilling machine is in place, and drilling, wherein the upper pile hole is connected with a high steel pipe pile after a set depth is drilled;
reaming and drilling a middle pile hole, wherein the middle pile hole is positioned at the bottom of the upper pile hole and in a rock stratum, and a drilling machine adopts a drilling bucket with sequentially increased diameters to perform reaming and drilling from inside to outside in a grading manner and keeps the aperture of the middle pile hole consistent with that of the upper pile hole;
and (3) blasting and removing slag from the lower pile hole, wherein the lower pile hole is positioned at the bottom of the middle pile hole and in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole, explosives are buried in the blasting holes and are subjected to loosening blasting, a drilling machine drills holes and removes slag until the set hole depth is reached, and the hole diameter of the lower pile hole is equal to or smaller than that of the upper pile hole.
In some embodiments, the method further comprises the following steps before the middle pile hole reaming drilling:
and a plurality of grouting pipes are inserted into a gap between the outer wall of the steel pipe pile and the inner wall of the upper pile hole, and the plurality of grouting pipes pour concrete to the bottom of the steel pipe pile along the circumference of the steel pipe pile until the concrete reaches the orifice of the upper pile hole.
In some embodiments, the upper pile hole isodiametric drilling further comprises the following steps:
and (4) locking construction, binding reinforcing steel bars around the center of the pile hole in a construction site and pouring concrete to form a locking, wherein the top of the locking is flush with the ground.
In some embodiments, in the middle pile hole reaming drilling process, the drilling machine adopts a drilling bucket with the diameter of 1.5m, a drilling bucket with the diameter of 2.5m and a drilling bucket with the diameter of 3.3m which are sequentially increased in diameter to perform stepped reaming drilling from inside to outside;
firstly, drilling by using a drilling bucket with the diameter of 1.5m, wherein the drilling depth is 1m lower than the bottom of a middle pile hole;
then, reaming and drilling by using a drilling bucket with the diameter of 2.5m, discharging slag by using the drilling bucket with the diameter of 1.5m when drilling at a set depth, and keeping the height of the slag soil in the central hole lower than the reaming depth during reaming and drilling;
and finally, reaming and drilling by using a drilling bucket with the diameter of 3.3m, discharging slag by using the drilling bucket with the diameter of 2.5m when the drilling depth is set, and keeping the height of the slag soil in the central hole lower than the reaming depth during reaming and drilling.
In some embodiments, when the diameter of the middle pile hole is smaller than that of the upper pile hole, the drilling machine drills downwards in a layered reaming mode by using a drilling bucket with the diameter of 3.3m, each layer of manual auxiliary reaming is performed by the drilling bucket with the diameter of 3.3m until the hole bottom of the middle pile hole is reached, and a protective cover with the diameter larger than 2.5m is arranged in the middle pile hole to serve as a manual operation platform during manual auxiliary reaming.
In some embodiments, during the blasting and slag removal of the lower pile hole, a blast hole guide frame is fixed at the bottom of the middle pile hole, a plurality of blast holes are formed under the positioning of the blast hole guide frame by using a crawler-type pneumatic drill, the depth of each blast hole is 10-15m, the diameter of each blast hole is 15cm, and the plurality of blast holes are sequentially arranged circumferentially from inside to outside.
In some embodiments, during the blasting and slag removal process of the lower pile hole, the explosives are bound by PVC pipes in blocks, the explosives are bound at intervals along the length direction of the PVC pipes and are placed into the blasting holes for loosening blasting, and after the loosening blasting is completed, a drill bucket with the diameter of 2.5m is used for drilling and slag removal until the set hole depth is reached.
In some embodiments, the method further comprises the following steps after the lower pile hole is blasted and slag is removed:
detecting the formed holes, and comparing a geological histogram drawn by drilling sampling after the lower pile hole is formed with an in-situ survey report histogram to judge whether the actual geology is consistent with the designed geology;
detecting the aperture, the hole depth and the hole pattern by using a hole detector to judge whether the requirements are met;
detecting the perpendicularity of the pile hole by using the relative position of the bottom edge of the measuring rope and the orifice;
and checking the center position of the pile hole by using a total station.
In some embodiments, the method further comprises the following steps after the lower pile hole is blasted and slag is removed:
the method comprises the following steps of (1) processing and installing a reinforcement cage, wherein the reinforcement cage is intensively processed in a reinforcement workshop by adopting a long-line method, and the reinforcement cage is put down section by section after being transported to the site to finish the installation of the reinforcement cage;
and (3) pouring concrete into the pile foundation, pouring underwater concrete by adopting a guide pipe method, and burying the bottom of the guide pipe 2-6m below the concrete surface.
In some embodiments, the method further comprises the following steps after the pile foundation is poured with concrete:
and when the strength of the pile foundation concrete reaches 70 percent and is not lower than 15MPa, or the age of the pile foundation concrete reaches 14 days, detecting the integrity of the pile foundation by adopting ultrasonic waves.
The beneficial effect that technical scheme that this application provided brought includes:
the embodiment of the application provides a construction method of a large-diameter steel pipe concrete reducing pile foundation, because the construction method sequentially adopts equal-diameter drilling of upper pile holes, steel pile casings are embedded after the central points of the pile holes are measured in a construction site, clay is used for backfilling and tamping, a drilling machine positions a drilling bucket and the centers of the steel pile casings in place and drills, and each time the upper pile holes are drilled to a set depth, the steel pipe piles are connected in a high mode; reaming and drilling a middle pile hole, wherein the middle pile hole is positioned at the bottom of the upper pile hole and in a rock stratum, and a drilling machine adopts a drilling bucket with sequentially increased diameters to perform reaming and drilling from inside to outside in a grading manner and keeps the aperture of the middle pile hole consistent with that of the upper pile hole; and (3) blasting and removing slag from the lower pile hole, wherein the lower pile hole is positioned at the bottom of the middle pile hole and in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole, explosives are buried in the blasting holes and are subjected to loosening blasting, a drilling machine drills holes and removes slag until the set hole depth is reached, and the hole diameter of the lower pile hole is equal to or smaller than that of the upper pile hole.
Therefore, according to the geological conditions of softness and hardness at the top of the pile hole, the applied construction method sequentially adopts the equal-diameter drilling of the upper pile hole, the reaming drilling of the middle pile hole, the blasting of the lower pile hole and the slag removal to carry out the step-by-step drilling construction. The upper pile hole is positioned in the soft texture layer, a drilling machine can be used for being matched with a drilling bucket to drill downwards layer by layer, and the construction efficiency is high; the middle pile hole is positioned in the rock stratum, and the drilling machine adopts a drilling bucket with the diameters sequentially increased to perform step-by-step hole expanding drilling from inside to outside, so that the hole forming efficiency of the middle pile hole is ensured; the lower pile hole is positioned in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole, explosives are buried in the blasting holes and are subjected to loosening blasting, and finally a drilling machine is used for drilling and removing slag until the set hole depth is reached. The construction method improves the utilization rate of the drilling machine, improves the hole forming efficiency of the pile hole and reduces the construction cost of the pile foundation.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an embodiment of the present application;
fig. 2 is a schematic view of the arrangement of the blasting holes according to the embodiment of the present application.
Reference numerals:
1. an upper pile hole; 2. a steel casing; 3. locking the opening; 4. steel pipe piles; 5. a middle pile hole;
6. and a lower pile hole.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The embodiment of the application provides a construction method for a large-diameter concrete-filled steel tube variable-diameter pile foundation, which can solve the problem that in the related art, a rotary drilling rig has a low drilling speed after entering a hard rock stratum, so that the construction cost of the rotary drilling rig in a rock entering stage is obviously increased.
Referring to fig. 1 and 2, an embodiment of the present application provides a method for constructing a large-diameter steel pipe concrete variable diameter pile foundation, where the method includes the following steps:
step 101, constructing a locking notch 3, binding reinforcing steel bars within the range of 1.7m around the center of a pile hole in a construction site, pouring concrete to form the locking notch 3, enabling the top of the locking notch 3 to be flush with the ground, and enabling the locking notch 3 to be used for ensuring that the hole top does not collapse in the process of connecting, inserting and driving the steel pipe pile 4 in the upper pile hole 1 and serving as a foundation of a reinforcing cage mounting support.
102, drilling an upper pile hole 1, burying a steel pile casing 2 after the upper pile hole 1 is positioned on a covering layer and measuring the center point of the pile hole on a construction site, and backfilling and tamping clay to ensure that the deviation of the plane position of the steel pile casing 2 is less than 5cm and the inclination is less than 0.5%; after the drilling machine is in place, a drilling bucket with the same diameter as the upper pile hole 1 is adopted to be aligned with the center of the steel casing 2, the allowable deviation of the drilling bucket and the center of the steel casing 2 is not more than 2cm, the drilling inserting precision is guaranteed, and the deviation of drilling holes is prevented.
Because the overburden geology is softer, can adopt the drilling bucket drilling of diameter 3.3m to bore on the overburden rig, the steel casing 2 should be avoided colliding in the drilling process, and high steel-pipe pile 4 is in time connect after every 3m of drilling in upper portion stake hole 1, and steel-pipe pile 4 utilizes hydraulic vibration hammer to insert to beat to follow-up, guarantees that downthehole dado is stable. The steel pipe pile 4 is connected with the axis of the steel pipe pile 4 in the hole in a high mode, the position of the steel pipe pile 4 is monitored in real time in the inserting and driving process, and the deviation is adjusted in time in the process when the deviation is too large, so that the installation quality of the steel pipe pile 4 is guaranteed. If the hole encounters an boulder, the drilling or the high-connection follow-up of the steel pipe pile 4 is difficult, and manual assistance is adopted.
103, drilling the middle pile hole 5, wherein the middle pile hole 5 is positioned at the bottom of the upper pile hole 1 and in the rock stratum, the middle pile hole 5 in the rock stratum is hard, if the drilling bucket with the diameter the same as that of the middle pile hole 5 is directly adopted for drilling, the drilling efficiency is low, the drilling bucket is seriously abraded, the progress is slow and uneconomic. Therefore, the hole section drilling machine adopts the drilling bucket with the diameter gradually increased to perform hole expanding drilling from inside to outside in a grading manner, so that the single rock layer scraping amount of the drilling bucket is reduced, the drilling efficiency is improved, the abrasion of the drilling bucket is reduced, the construction cost is reduced, and the hole diameter of the middle pile hole 5 is consistent with the hole diameter of the upper pile hole 1 until the preset hole depth is reached.
And 104, blasting and removing slag from the lower pile hole 6, wherein the lower pile hole 6 is positioned at the bottom of the middle pile hole 5 and in the bedrock, and if the drilling bucket is continuously used for carrying out stepped reaming from inside to outside due to the fact that the bedrock is hard, the drilling efficiency is low, the drilling bucket is seriously abraded, the progress is slow and the drilling is not economical. Therefore, the hole section drills a plurality of blasting holes downwards at the bottom of the middle pile hole 5, explosives are buried in the blasting holes and are subjected to loosening blasting, a drilling machine utilizes a drilling bucket to drill holes and remove slag until the set hole depth is reached, and the base rock is hard and can be used as a foundation of large-scale building engineering, so that the aperture of the lower pile hole 6 can be smaller than or equal to that of the upper pile hole 1.
According to the construction method of the application embodiment, the upper pile hole 1 is adopted for drilling, the middle pile hole 5 is subjected to reaming drilling, the lower pile hole 6 is subjected to blasting and slag removal in sequence according to the geological conditions that the upper part of the pile hole is soft and the lower part is hard, and step-by-step drilling construction is carried out. The upper pile hole 1 is positioned in the soft texture layer, a drilling machine can be used for being matched with a drilling bucket to drill downwards layer by layer, and the construction efficiency is high; the middle pile hole 5 is positioned in the rock stratum, and the drilling machine adopts a drilling bucket with the diameter sequentially increased to perform step-by-step hole expanding drilling from inside to outside, so that the hole forming efficiency of the middle pile hole 5 is ensured; the lower pile hole 6 is positioned in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole 5, explosives are buried in the blasting holes and are subjected to loosening blasting, and finally a drilling machine is used for drilling and removing slag until the set hole depth is reached. The construction method improves the utilization rate of the drilling machine, improves the hole forming efficiency of the pile hole and reduces the construction cost of the pile foundation.
In some alternative embodiments, referring to fig. 1, the present application provides a method for constructing a large-diameter steel pipe concrete variable diameter pile foundation, where the method further includes the following steps between step 102 and step 103:
and a plurality of grouting pipes are inserted into a gap between the outer wall of the steel pipe pile 4 and the inner wall of the upper pile hole 1, and the plurality of grouting pipes pour concrete to the bottom of the steel pipe pile 4 along the circumference of the steel pipe pile 4 in the same direction until the concrete reaches the orifice of the upper pile hole 1.
Because the pile foundation is designed to be a friction pile, in the inserting, driving and following process of the steel pipe pile 4, a gap exists between the steel pipe pile 4 and the hole wall of the upper pile hole 1 to influence the bearing capacity of the pile foundation, so that grouting treatment needs to be carried out between the steel pipe pile 4 and the hole wall of the upper pile hole 1. After grouting treatment, the friction between the steel pipe pile 4 and the hole wall of the upper pile hole 1 is improved, the steel pipe pile 4 is prevented from sinking in the drilling process of the middle pile hole 5, and meanwhile, the surface of the steel pipe pile 4 can be protected from corrosion.
In some optional embodiments, referring to fig. 1, the present application provides a large-diameter steel pipe concrete variable diameter pile foundation construction method, in the middle pile hole 5 drilling process of step 103, a drilling machine performs stepped reaming drilling from inside to outside by using a drilling bucket with a diameter of 1.5m, a drilling bucket with a diameter of 2.5m and a drilling bucket with a diameter of 3.3m, which are sequentially increased in diameter.
Firstly, a drilling bucket with the diameter of 1.5m is used for drilling, and the drilling depth reaches a position 1m lower than the bottom of the middle pile hole 4.
And then reaming and drilling by using a drilling bucket with the diameter of 2.5m, discharging slag by using the drilling bucket with the diameter of 1.5m when the set depth is drilled, and keeping the height of the slag soil in the central hole lower than the reaming depth when the reaming and drilling are carried out.
And finally, reaming and drilling by using a drilling bucket with the diameter of 3.3m, discharging slag by using the drilling bucket with the diameter of 2.5m when the drilling depth is set, and keeping the height of the slag soil in the central hole lower than the reaming depth during reaming and drilling.
When the aperture of the middle pile hole 4 is smaller than that of the upper pile hole 1, the drilling machine uses a drilling bucket with the diameter of 3.3m to perform layered reaming drilling downwards according to 1.5m, and the drilling bucket with the diameter of 3.3m performs manual auxiliary reaming once when drilling one layer until the hole bottom of the middle pile hole 5 is reached.
During the manual auxiliary reaming, a protective cover with the diameter larger than 2.5m is arranged at the top of a pile hole with the diameter of 2.5m in the middle to serve as a manual operation platform, and a constructor is prevented from falling into a well.
In some alternative embodiments, referring to fig. 2, the present application provides a method for constructing a large-diameter steel pipe concrete variable diameter pile foundation, in the process of blasting and slag removal of the lower pile hole 6 in step 104, a blasthole guide frame is fixed at the bottom of the middle pile hole 5, a plurality of blastholes are arranged by using a crawler-type pneumatic drill and under the positioning action of the blasthole guide frame, the depth of each blasthole is 10-15m, the diameter of each blasthole is 15cm, and the blastholes are sequentially arranged circumferentially from inside to outside.
After the plurality of blasting holes are formed, the explosives are bound by hard PVC pipes in blocks, the explosives are bound at intervals along the length direction of the hard PVC pipes and are placed into the blasting holes for loosening blasting, and after the loosening blasting is completed, a drilling bucket with the diameter of 2.5m is used for drilling and slag removal until the set hole depth is reached.
In some optional embodiments, the present application provides a method for constructing a large-diameter steel pipe concrete pile with variable diameter, where the method further includes the following steps after step 104 is completed:
step 105, detecting the formed hole, and comparing a geological histogram drawn by drilling and sampling after the lower pile hole 6 is formed with an in-situ survey report histogram to judge whether the actual geology is consistent with the designed geology; detecting the aperture, the hole depth and the hole pattern by using a hole detector to judge whether the requirements are met; detecting the perpendicularity of the pile hole by using the relative position of the bottom edge of the measuring rope and the orifice; and checking the center position of the pile hole by using a total station.
And step 106, processing and installing the reinforcement cage, wherein the reinforcement cage is processed in a centralized manner in a reinforcement workshop by a long-line method, and the reinforcement cage is transferred section by section after being transported to the site, so that the reinforcement cage is installed.
And 107, pouring concrete into the pile foundation, namely pouring underwater concrete by adopting a guide pipe method, and when the underwater concrete is poured to the joint of the reducing section, burying the bottom of the guide pipe 2-6m below the concrete surface so as to avoid pile breakage after the guide pipe is pulled out.
And 108, when the strength of the pile foundation concrete reaches 70 percent and is not lower than 15MPa, or the age of the pile foundation concrete reaches 14 days, detecting the integrity of the pile foundation by adopting ultrasonic waves.
Principle of operation
The embodiment of the application provides a construction method of a large-diameter steel pipe concrete reducing pile foundation, because the construction method adopts the drilling of an upper pile hole 1 in sequence, a steel pile casing 2 is embedded after the central point of the pile hole is measured at a construction site, and is backfilled and tamped by clay, a drilling machine aligns and drills a drilling bucket with the center of the steel pile casing 2 after being in place, and the upper pile hole 1 is connected with a steel pipe pile 4 after being drilled to a set depth; drilling a middle pile hole 5, wherein the middle pile hole 5 is positioned at the bottom of the upper pile hole 1 and in a rock stratum, and a drilling machine adopts a drilling bucket with sequentially increased diameters to perform step-by-step reaming drilling from inside to outside and keeps the aperture of the middle pile hole consistent with that of the upper pile hole; and (3) blasting and slag removal of the lower pile hole 6, wherein the lower pile hole 6 is positioned at the bottom of the middle pile hole 4 and in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole 4, explosives are buried in the blasting holes and are subjected to loosening blasting, a drilling machine drills holes and removes slag until the set hole depth is reached, and the aperture of the lower pile hole 6 is equal to or smaller than that of the upper pile hole 1.
Therefore, the applied construction method adopts the upper pile hole 1 to drill, the middle pile hole 5 to drill and the lower pile hole 6 to blast and remove slag to carry out step-by-step drilling construction according to the geological conditions that the upper part of the pile hole is soft and the lower part is hard. The upper pile hole 1 is positioned in the soft texture layer, and can be drilled downwards in an equal diameter mode layer by using a drilling machine and a drilling bucket, so that the construction efficiency is high; the middle pile hole 5 is positioned in the rock stratum, and the drilling machine adopts a drilling bucket with the diameter sequentially increased to perform step-by-step hole expanding drilling from inside to outside, so that the hole forming efficiency of the middle pile hole 5 is ensured; the lower pile hole 6 is positioned in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole 5, explosives are buried in the blasting holes and are subjected to loosening blasting, and finally a drilling machine is used for drilling and removing slag until the set hole depth is reached. The construction method improves the utilization rate of the drilling machine, improves the hole forming efficiency of the pile hole and reduces the construction cost of the pile foundation.
In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
It is noted that, in the present application, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A construction method of a large-diameter steel pipe concrete variable-diameter pile foundation is characterized by comprising the following steps:
drilling an upper pile hole (1) in an equal diameter mode, burying a steel casing (2) after measuring the center point of the pile hole in a construction site, backfilling and tamping with clay, aligning and drilling the center of the steel casing (2) by using a drilling bucket in the equal diameter mode with the upper pile hole (1) after a drilling machine is in place, and connecting a high steel pipe pile (4) after the drilling depth of the upper pile hole (1) is set;
reaming and drilling the middle pile hole (5), wherein the middle pile hole (5) is positioned at the bottom of the upper pile hole (1) and in the rock formation, and a drilling machine adopts a drilling bucket with sequentially increased diameters to perform graded reaming and drilling from inside to outside and keeps the aperture of the middle pile hole (5) consistent with that of the upper pile hole (1);
and (3) blasting and slag removal are carried out on the lower pile hole (6), the lower pile hole (6) is positioned at the bottom of the middle pile hole (5) and is positioned in the bedrock, a plurality of blasting holes are drilled downwards at the bottom of the middle pile hole (5), explosives are buried in the blasting holes and are subjected to loosening blasting, a drilling machine is used for drilling and slag removal until the set hole depth is reached, and the aperture of the lower pile hole (6) is equal to or smaller than that of the upper pile hole (1).
2. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, wherein the step of before reaming and drilling the middle pile hole further comprises the following steps:
and a plurality of grouting pipes are inserted into a gap between the outer wall of the steel pipe pile (4) and the inner wall of the upper pile hole (1), and the plurality of grouting pipes pour concrete to the bottom of the steel pipe pile (4) along the circumference of the steel pipe pile (4) in the same direction until the concrete reaches the orifice of the upper pile hole (1).
3. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, wherein the step of drilling the upper pile hole (1) in an equal diameter mode further comprises the following steps:
and (3) constructing the locking notch, binding reinforcing steel bars around the center of the pile hole in a construction site, pouring concrete to form the locking notch (3), and leveling the top of the locking notch (3) with the ground.
4. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, characterized in that:
in the reaming drilling process of the middle pile hole (5), the drilling machine adopts a drilling bucket with the diameter of 1.5m, a drilling bucket with the diameter of 2.5m and a drilling bucket with the diameter of 3.3m which are sequentially increased in diameter to perform grading reaming drilling from inside to outside;
firstly, drilling by using a drilling bucket with the diameter of 1.5m, wherein the drilling depth is 1m lower than the bottom of a middle pile hole (5);
then, reaming and drilling by using a drilling bucket with the diameter of 2.5m, discharging slag by using the drilling bucket with the diameter of 1.5m when drilling at a set depth, and keeping the height of the slag soil in the central hole lower than the reaming depth during reaming and drilling;
and finally, reaming and drilling by using a drilling bucket with the diameter of 3.3m, discharging slag by using the drilling bucket with the diameter of 2.5m when the drilling depth is set, and keeping the height of the slag soil in the central hole lower than the reaming depth during reaming and drilling.
5. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 4, characterized in that:
when the aperture of the middle pile hole (5) is smaller than that of the upper pile hole (1), the drilling machine drills downwards in a layered reaming mode by using a drilling bucket with the diameter of 3.3m, each layer of manual auxiliary reaming is performed by the drilling bucket with the diameter of 3.3m until the hole bottom of the middle pile hole (5) is reached, and a protective cover with the diameter larger than 2.5m is arranged in the middle pile hole (5) to serve as a manual operation platform during manual auxiliary reaming.
6. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, characterized in that:
in the blasting and slag removing process of the lower pile hole (6), a blasthole guide frame is fixed at the hole bottom of the middle pile hole (5), a plurality of blasting holes are formed under the positioning of the blasthole guide frame by using a crawler-type pneumatic drill, the depth of each blasting hole is 10-15m, the diameter of each blasting hole is 15cm, and the blasting holes are sequentially and circumferentially arranged from inside to outside.
7. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, characterized in that:
and in the blasting and slag removing process of the lower pile hole (6), the explosives are bound by PVC pipes in blocks, the explosives are bound at intervals along the length direction of the PVC pipes and are placed into the blasting holes for loosening blasting, and after the loosening blasting is finished, a drill bucket with the diameter of 2.5m is used for drilling and slag removing until the set hole depth is reached.
8. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, wherein after the lower pile hole is blasted and slag is removed, the method further comprises the following steps:
detecting the formed holes, namely comparing a geological histogram drawn by drilling sampling after the lower pile hole (6) is formed with an in-situ survey report histogram to judge whether the actual geology is consistent with the designed geology;
detecting the aperture, the hole depth and the hole pattern by using a hole detector to judge whether the requirements are met;
detecting the perpendicularity of the pile hole by using the relative position of the bottom edge of the measuring rope and the orifice;
and checking the center position of the pile hole by using a total station.
9. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 1, wherein after the lower pile hole is blasted and slag is removed, the method further comprises the following steps:
the method comprises the following steps of (1) processing and installing a reinforcement cage, wherein the reinforcement cage is intensively processed in a reinforcement workshop by adopting a long-line method, and the reinforcement cage is put down section by section after being transported to the site to finish the installation of the reinforcement cage;
and (3) pouring concrete into the pile foundation, pouring underwater concrete by adopting a guide pipe method, and burying the bottom of the guide pipe 2-6m below the concrete surface.
10. The construction method of the large-diameter steel pipe concrete variable diameter pile foundation according to claim 9, wherein the pile foundation after concrete pouring further comprises the following steps:
and when the strength of the pile foundation concrete reaches 70 percent and is not lower than 15MPa, or the age of the pile foundation concrete reaches 14 days, detecting the integrity of the pile foundation by adopting ultrasonic waves.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114875899A (en) * | 2022-06-11 | 2022-08-09 | 一山(北京)岩土工程有限公司 | Hard stratum pore-forming pile-forming construction process |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103195365A (en) * | 2013-03-29 | 2013-07-10 | 徐州徐工基础工程机械有限公司 | Rotary drilling rig hard rock stratum step drilling construction process |
| CN109208589A (en) * | 2018-10-11 | 2019-01-15 | 中交上海港湾工程设计研究院有限公司 | A kind of embedding rock single pile grouting system of embedded type major diameter and construction method |
| CN109629455A (en) * | 2019-02-27 | 2019-04-16 | 中交路桥北方工程有限公司 | The construction method of highway reconstruction bridge |
| CN110387879A (en) * | 2019-06-27 | 2019-10-29 | 中交第二航务工程局有限公司 | A kind of concrete filling pile construction method of hydraulic vibration hammer hidden pipe |
| US20200248425A1 (en) * | 2019-01-31 | 2020-08-06 | Terracon Consultants, Inc. | Reinforcement structures for tensionless concrete pier foundations and methods of constructing the same |
| CN111749612A (en) * | 2020-06-11 | 2020-10-09 | 武汉大学 | Excavation method for large-diameter offshore rock-socketed pile foundation pit |
-
2021
- 2021-11-15 CN CN202111349768.6A patent/CN114108611B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103195365A (en) * | 2013-03-29 | 2013-07-10 | 徐州徐工基础工程机械有限公司 | Rotary drilling rig hard rock stratum step drilling construction process |
| CN109208589A (en) * | 2018-10-11 | 2019-01-15 | 中交上海港湾工程设计研究院有限公司 | A kind of embedding rock single pile grouting system of embedded type major diameter and construction method |
| US20200248425A1 (en) * | 2019-01-31 | 2020-08-06 | Terracon Consultants, Inc. | Reinforcement structures for tensionless concrete pier foundations and methods of constructing the same |
| CN109629455A (en) * | 2019-02-27 | 2019-04-16 | 中交路桥北方工程有限公司 | The construction method of highway reconstruction bridge |
| CN110387879A (en) * | 2019-06-27 | 2019-10-29 | 中交第二航务工程局有限公司 | A kind of concrete filling pile construction method of hydraulic vibration hammer hidden pipe |
| CN111749612A (en) * | 2020-06-11 | 2020-10-09 | 武汉大学 | Excavation method for large-diameter offshore rock-socketed pile foundation pit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114875899A (en) * | 2022-06-11 | 2022-08-09 | 一山(北京)岩土工程有限公司 | Hard stratum pore-forming pile-forming construction process |
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