CN112411529A - Rock-entering pore-forming method of hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig - Google Patents
Rock-entering pore-forming method of hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig Download PDFInfo
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- CN112411529A CN112411529A CN202011279834.2A CN202011279834A CN112411529A CN 112411529 A CN112411529 A CN 112411529A CN 202011279834 A CN202011279834 A CN 202011279834A CN 112411529 A CN112411529 A CN 112411529A
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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
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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
- E21B4/00—Drives for drilling, used in the borehole
- E21B4/06—Down-hole impacting means, e.g. hammers
- E21B4/14—Fluid operated hammers
Abstract
The invention belongs to the technical field of civil engineering pile foundation engineering, and particularly relates to a rock-entering pore-forming method of a hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig. Comprises the following steps. S100, positioning the drilled pile. S200, placing the rotary drilling rig in place and constructing. S300, when the drilling is carried out to the bedrock surface, the drilling is stopped, the drill rod is lifted, and the rotary drilling rig exits from the construction pile position. S400, arranging a plurality of down-the-hole pre-drilled holes in the drilled pile. S500, manufacturing a small-diameter down-the-hole drill sleeve positioning frame according to the determined number of down-the-hole pre-drilled holes and the section size of the drilled pile. S600, erecting a small-diameter down-the-hole hammer sleeve positioner on the pile casing. S700, after the down-the-hole hammer sleeve is in place, a wooden wedge is driven into a position between the down-the-hole hammer sleeve and a sleeve plate positioning hole in a drill sleeve positioning frame, the down-the-hole hammer with the small diameter is in place, and the bedrock rock entering section is pre-drilled hole by hole to the designed rock entering depth. And S800, finishing hole forming. S900, pulling out the down-the-hole drill sleeve positioning frame and the down-the-hole drill sleeve. S1000-cleaning the hole of the lower guide pipe.
Description
Technical Field
The invention belongs to the technical field of civil engineering pile foundation engineering. The construction method is characterized in that a small-diameter down-the-hole hammer is introduced to pre-drill a small hole in the process of drilling the hard bedrock socketed pile into the rock by a rotary drilling rig so as to reduce the construction difficulty of entering the rock and accelerate the construction progress. The construction method is based on the rock breaking principle of a down-the-hole hammer and the combination of the down-the-hole hammer and a rotary drilling rig.
Background
The hard bedrock socketed pile is drilled into the rock section, the difficulty of pile foundation construction is existed, when the pile length is less than 30 m without underground water, the hole is dug by manpower, after the hole is drilled by a pneumatic pick, explosive is filled in the hole to blast the hole, but when the pile length is more than 30 m, the hole is formed by the socketed section when the manual hole forming process is not allowed, if the pile end is positioned on hard rocks such as gneiss, the hardness can reach 140MPa, which is equivalent to the theoretical C90 concrete strength, if no auxiliary measures are taken, the hole is formed by directly adopting a drilling machine, and the single depth of the rock stratum does not exceed 5 cm. The single-pile hole forming time is 20 hours in short time, the length is 90 hours in long time, the requirement of the construction period can not be met, and the drilling machine is overloaded during the rock entering process, so that an engine is blocked, a drill rod is broken, the consumption of hard alloy drilling teeth is high, and the cost is very high.
The prior art is as follows: china rescue Kamylong gymnasium in Shanxi Jian Gong group 8.2004. The project is located at the low position of the central square of Yawenda city of the capital of Kamylon, belongs to the fields of miscellaneous fill and rainwater soaking of a foundation, and is high in underground water level, and hard gneiss is 5-13 m below the ground surface. Therefore, 785 reinforced concrete rock-socketed piles with the diameter of 500mm and the length of 9-14 m are selected as the design drawing. The depth of the pile end into the rock is required to be 1 meter. The gneiss hardness was 139 mpa. This high rock hardness, equivalent to the theoretical strength of C90 concrete, is rare in construction. Therefore, through technical demonstration, the process mainly entering the rock is researched and conquered. And finally, forming holes in the soil layer by using a rotary drilling rig, then changing the hole into a starting down-the-hole hammer with the same diameter for rock drilling, and after the holes are formed, placing a reinforcement cage for pouring concrete to form the pile.
In the pore-forming stage, the rotary drilling rig can smoothly form pores in a soil layer, but after a drill rod is pulled out, the pore wall of the miscellaneous fill is difficult to maintain, and the miscellaneous fill has hole collapse and necking. The wall is protected by traditional mud and sediment at the bottom of the hole is cleaned away, and even the more the hole is cleaned, the more serious the collapsed hole is. Then only the method of lowering the steel casing to protect the wall can be adopted. The method is characterized in that after a rock is seen, the drilling depth of a drill rod is measured, a steel casing with the diameter of 500mm and the same length is processed and placed down, a down-the-hole hammer is mechanically adjusted up to carry out rock drilling operation, however, the plane of a bed rock is not an ideal plane, the steel casing and the bed rock surface are not in tight contact, so that the pneumatic down-the-hole hammer impacts the vibration of the rock, disturbance is formed on the outer side of the steel casing, meanwhile, when the air hammer vibrates, ejected high-pressure air is flushed out from a gap between the steel casing and the bed rock surface, larger damage is caused to a hole wall, the sediment thickness is increased, the sediment thickness is difficult to clear the hole and reach the standard, the volume of a pile side is seriously enlarged, the filling coefficient of concrete pouring greatly exceeds the standard, and the over-pouring amount reaches an unacceptable degree.
12 test piles are completed within 40 days, the pouring amount of each pile is inconsistent with the designed pile length, the exact depth of a formed hole is not clear, and the steel pile casing and the steel reinforcement cage are processed on site. The detection result after pile forming is qualified in the dynamic size strain detection, which shows that the integrity of the pile body is good. However, the static load test result is only 60 percent qualified, and the 60 percent settlement exceeds the range, and the test shows that the adoption of the pneumatic down-the-hole hammer with the same cross section as the pile diameter to carry out the hole forming process on the bed rock surface is not preferable.
The project relies on research and development of the Wulu wood-field-shaped viaduct project. The viaduct project of the Wulu wood-Qi field is located in the Clarityi road of Wulu wood-Qi city, the pile foundation adopts the reinforced concrete rock-socketed cast-in-place pile with the design hole depth of 17-35m, the pile diameter of 1200mm and 1500mm, the rock-entering depth is 5-25 m, according to the geotechnical engineering investigation report, the field stratum mainly comprises the cobbles, the completely weathered argillaceous siltstones, the strongly weathered argillaceous siltstones, the moderately weathered argillaceous siltstones and the slightly weathered argillaceous siltstones, and the construction difficulty is very high. The natural climate characteristic of Wulu wood is short in construction period every year, and the project is located in a luxurious zone of a city area, so that the normal travel and life of citizens are seriously influenced, the requirement on the construction period of a pile foundation part is one month, and the requirement on the construction progress is high.
During the test, according to the past experience, the short rock-socketed auger and the barrel-type rock-socketed drill are alternately used, although the preset depth can be drilled, the construction time is too long, the single depth of penetration in the rock stratum is not more than 5cm, the single-pile hole forming time is 20 hours if short, and 86 hours if long, so that the requirement of the construction period can not be met.
Moreover, due to overload work of the drilling machine in the rock entering process, an engine is blocked, a drill rod is broken, the consumption of hard alloy drilling teeth is high, the cost is very high, and in order to ensure the construction period and reduce the cost, multiple discussion and research determine that a small-diameter down-the-hole hammer is matched with a rotary drilling machine to carry out construction of a bedrock section.
Disclosure of Invention
The invention provides a rock-entering hole-forming construction method of a rotary drilling rig assisted by a small-diameter down-the-hole hammer of a hard bedrock socketed pile.
The invention adopts the following technical scheme: a rock-entering pore-forming construction method of a rotary drilling rig assisted by a small-diameter down-the-hole hammer of a hard bedrock socketed pile in a high water level field comprises the following steps.
S100, positioning the drilled pile position, and burying the pile casing by taking the center of the pile as an original point.
S200, placing the rotary drilling rig in place, constructing, drilling and taking soil, and injecting wall protection slurry into the hole.
S300, when the drilling is carried out to the bedrock surface, the drilling is stopped, the drill rod is lifted, and the rotary drilling rig exits from the construction pile position.
S400, arranging a plurality of down-the-hole pre-drilled holes in the drilled pile.
S500, manufacturing a small-diameter down-the-hole drill sleeve positioning frame according to the determined number of pre-drilled down-the-hole holes and the section size of the drilled pile, and installing the drill sleeve positioning frame in the drilled pile; the drill sleeve positioning frame comprises a frame body arranged in the drilled pile, and sleeve plate positioning holes which correspond to the down-the-hole pre-drilled holes one by one are arranged in the middle of the frame body.
S600, erecting a small-diameter down-the-hole hammer sleeve positioner on the pile casing, and sequentially placing down-the-hole hammer sleeves in the small-diameter down-the-hole hammer sleeve positioner.
S700, driving a wooden wedge between the down-the-hole hammer sleeve and a sleeve plate positioning hole on a drill sleeve positioning frame after the down-the-hole hammer sleeve is in place, pre-drilling a bedrock rock entry section hole by hole to a designed rock entry depth, and withdrawing the small-diameter down-the-hole hammer from a pile position after all down-the-hole pre-drilling holes are completed; and pulling out the down-the-hole hammer casing and dismounting the small-diameter down-the-hole hammer casing positioner.
And S800, putting the rotary drilling rig in place again, comprehensively crushing the rock stratum of the pre-drilled pile foundation rock entering section by using the cylindrical rock-socketed drill bit and the spiral rock-socketed drill bit, fishing out the drilling slag, and finishing hole forming.
S900, pulling out the down-the-hole drill sleeve positioning frame and the down-the-hole drill sleeve.
S1000, cleaning holes of a lower guide pipe, and pouring concrete to form a pile after the cleaning is finished.
In the step S400, the down-the-hole pre-drilled holes are uniformly distributed in the drilled pile, the area of each down-the-hole pre-drilled hole is equal, and the area of all the down-the-hole pre-drilled holes accounts for 40% -60% of the area of the drilled hole.
In the step S500, the diameter of the sleeve hole position of the sleeve positioner is 0.1-1 cm larger than the outer diameter of the sleeve of the down-the-hole hammer; wherein the positioning hole of the sleeve plate at the lower end of the sleeve positioning frame is 0.5cm +2mm larger than the outer diameter of the down-the-hole hammer sleeve; the sleeve positioning hole at the upper end of the sleeve positioning frame is larger than the outer diameter of the down-the-hole hammer sleeve by 1.0cm +2 mm; the sleeve positioning frame adopts different sizes according to the bedrock burial depth, and the height of the sleeve positioning frame can be 2 m-6 m.
The technical problems solved by the invention are as follows:
(1) and the small-diameter down-the-hole hammer is adopted to pre-drill the small-diameter hole to break the rock surface of the bedrock, so that the difficulty of the rotary drilling rig in drilling the bedrock is reduced.
(2) The underwater down-the-hole drill is used for hole forming in a high water level field by adopting the steel sleeve, so that the impact damage of high-pressure airflow to the side wall of the pile hole when the down-the-hole drill is used for drilling on uneven foundation rock surfaces in the high water level field is avoided.
The working principle of the down-the-hole hammer assisted rotary drilling rig pore-forming is as follows:
(1) the down-the-hole hammer is driven by compressed air as power, and a piston in a cylinder body of the down-the-hole hammer makes axial reciprocating motion, so that the rock stratum is subjected to crushing damage, and the rock entering function is achieved. The method overcomes the defect of single cutting and crushing in the conventional drilling, has the advantages of high drilling efficiency, good hole forming quality and lower cost, and is a preferred process for crushing hard rocks and loose boulders.
(2) The large-diameter down-the-hole hammer is not enough for construction, because the natural base rock surface is not a plane in an ideal state, the base rock surface is inclined or uneven, and when the down-the-hole hammer with the same diameter as a pile hole is used for forming the hole, the down-the-hole drill bit cannot be in complete contact with the base rock surface. The strong pneumatic pressure can impact from the side face of the drill bit to impact and damage the side wall of the pile hole, so that the pile forming quality is seriously influenced, the pouring amount of concrete is increased, waste is caused, and the engineering cost is increased.
(3) The advantage of the auxiliary rotary drilling of the small-diameter down-the-hole hammer is utilized, the advantage that the down-the-hole drill quickly and efficiently damages the hard bedrock is utilized, meanwhile, the diameter is equal to below 1/10 of the aperture of the pile hole, and the influence of the uneven inclined plane of the rock surface is greatly reduced due to the small diameter, and the defects are overcome or can be ignored. And drilling a certain number of small-diameter auxiliary holes at the set pile position to enable the bedrock at the position to be honeycomb-coal-shaped, and then performing comprehensive construction on the rock surface of the pile foundation by using a short spiral rock-socketed drill and a barrel rock-socketed drill bit of a rotary drilling rig.
Arranging principle of down-the-hole hammer:
under the condition that the rock characteristics are the same, the larger the pre-drilling hole diameter is, the stronger the damage to the whole rock structure is, but the drilling efficiency is reduced; the smaller the drill hole diameter, the higher the pre-drilling efficiency, but the less the damage to the rock overall structure. The number of the budget holes is increased, the construction cost is not increased, and the optimal construction effect is achieved under the condition that the diameter of the drilled holes is in inverse proportion to the number of the drilled holes, so that the design key of the pre-drilled holes is achieved.
The pre-drilled holes are uniformly distributed in the drilled pile, and the shared surface of each hole is approximately equal, which is the basic principle of pre-drilled hole arrangement. The ratio of the area of the drilled pile to the area of the pre-drilled hole is an important parameter for the pre-drilled hole design. Through experiments, the pre-drilling area accounts for 40% -60% of the drilling area, and an ideal pre-drilling effect can be achieved.
Compared with the prior art, the invention has the following beneficial effects:
the construction technology of the small-diameter down-the-hole hammer pre-drilling auxiliary rotary drilling rig destroys a hard foundation stratum in a pile hole in advance, and greatly improves the construction efficiency of the rotary drilling rig. A Chinese character 'tian' shaped road viaduct project in Wulu-mu-qi city. The depth of the holes is 17-35m, the hole forming time of each hole is shortened to about 5 hours from the original 20 hours, the construction period is greatly shortened, the construction cost is greatly reduced, and considerable economic and social benefits are obtained.
The combination of the pneumatic down-the-hole hammer drilling process and the rotary drilling rig drilling process makes full use of the advantage of the fast construction progress of the down-the-hole hammer on the small-caliber hard bedrock stratum, and avoids the increase of the filling amount caused by the large damage of the large-caliber down-the-hole hammer gas action on the uneven bedrock surface to the pile wall soil layer. The method has the advantages that the serious defects of thick sediment at the bottom of the hole and the like are utilized, the advantage that the rotary drilling rig can progress quickly at the bottom of the large-caliber bottom layer is utilized, meanwhile, the field of construction of the rotary drilling rig for the medium-hard bedrock stratum is widened, the construction efficiency of the rotary drilling rig in the medium-hard bedrock stratum is improved, and technical reference and experience reference are provided for the rotary drilling rig to construct in similar geology.
Drawings
FIG. 1 is a schematic view of a down-the-hole drill casing positioning frame installation;
FIG. 2 is a top view of a down-the-hole drill casing positioning frame;
in the figure, 1-a protective cylinder, 2-a down-the-hole drill sleeve positioning frame, 3-a down-the-hole drill sleeve, 4-a frame body and 5-a sleeve plate positioning hole.
Detailed Description
A rock-entering pore-forming construction method of a small-diameter down-the-hole hammer assisted rotary drilling rig of a hard bedrock socketed pile in a high water level field comprises the following steps,
s100, positioning a drilled pile position, and burying a pile casing by taking the center of the pile as an original point;
s200, placing a rotary drilling rig in place, constructing, drilling and taking soil, and injecting wall protection slurry into a hole;
s300, when the drilling is carried out to the bedrock surface, stopping drilling, lifting a drill rod, and withdrawing the rotary drilling rig from the construction pile position;
s400, arranging a plurality of down-the-hole pre-drilled holes in the drilled pile;
s500, manufacturing a small-diameter down-the-hole drill sleeve positioning frame according to the determined number of pre-drilled down-the-hole holes and the section size of the drilled pile, and installing the drill sleeve positioning frame in the drilled pile; the drill sleeve positioning frame comprises a frame body 4 arranged in the drilled pile, and sleeve plate positioning holes 5 which correspond to the down-the-hole pre-drilled holes one by one are arranged in the middle of the frame body 4;
s600, erecting a small-diameter down-the-hole hammer sleeve positioner on the pile casing, and sequentially placing down-the-hole hammer sleeves in the small-diameter down-the-hole hammer sleeve positioner;
s700, driving a wooden wedge between the down-the-hole hammer sleeve and a sleeve plate positioning hole on a drill sleeve positioning frame after the down-the-hole hammer sleeve is in place, pre-drilling a bedrock rock entry section hole by hole to a designed rock entry depth, and withdrawing the small-diameter down-the-hole hammer from a pile position after all down-the-hole pre-drilling holes are completed; pulling out the down-the-hole hammer sleeve and dismounting the small-diameter down-the-hole hammer sleeve positioner;
s800, putting the rotary drilling rig in place again, comprehensively crushing the rock stratum of the pre-drilled pile foundation rock entering section by using a cylindrical rock-socketed drill bit and a spiral rock-socketed drill bit, fishing out drilling slag, and finishing hole forming;
s900, pulling out the down-the-hole drill sleeve positioning frame and the down-the-hole drill sleeve;
s1000, cleaning holes of a lower guide pipe, and pouring concrete to form a pile after the cleaning is finished.
In the step S400, the down-the-hole pre-drilled holes are uniformly distributed in the drilled pile, the area of each down-the-hole pre-drilled hole is equal, and the area of all the down-the-hole pre-drilled holes accounts for 40% -60% of the area of the drilled hole.
In the step S500, the diameter of the sleeve hole position of the sleeve positioner is 0.1-1 cm larger than the outer diameter of the sleeve of the down-the-hole hammer; wherein the positioning hole of the sleeve plate at the lower end of the sleeve positioning frame is 0.5cm +2mm larger than the outer diameter of the down-the-hole hammer sleeve; the sleeve positioning hole at the upper end of the sleeve positioning frame is larger than the outer diameter of the down-the-hole hammer sleeve by 1.0cm +2 mm; the sleeve positioning frame adopts different sizes according to the bedrock burial depth, and the height of the sleeve positioning frame can be 2 m-6 m.
In step S400, a method for determining the number of small-diameter down-the-hole drill holes is provided.
(1) Preparing a down-the-hole drill:
1) drilling tool combination: 50-940 variable drill rod and 120-ball tooth impact drill bit.
2) Drilling parameters: and (3) carrying out wind pressure of 0.5-0.7MPa, rotation speed of 25-30r/min and drilling pressure of 300-.
(2) The hole distribution scheme is as follows:
aiming at the pile with the diameter of 1.2m, a 120mm impactor is adopted on the spot, and 4, 5 and 6 pre-drilled holes are respectively arranged at the corresponding positions of the pile holes No. 1, No. 2 and No. 3 according to the equal division principle so as to test which ratio has the best comprehensive effect.
(3) Down-the-hole hammer construction
The method comprises the steps of firstly drawing a pile hole position on an original site by taking a pile center as an original point, drawing a small hole position according to a hole distribution principle, sequentially drilling the small holes to a preset hole depth by a down-the-hole drill in a certain sequence, and withdrawing the down-the-hole drill after the small holes in the pile hole are completely finished.
During construction, a hard and flat working surface is formed on the ground surface to ensure that a drilling machine body is horizontal and a drill rod is vertical. And (3) slightly pressing the slow drill after the construction is started, checking the verticality of the drill hole at any time, and adjusting in time to ensure that the drill hole cannot deviate out of the pile hole, otherwise, causing great difficulty to the construction of the next rotary drilling rig. The depth of each pre-drilled hole is 100mm higher than the design depth of the pile hole, so that the rotary drilling rig can be constructed according to the design depth. The number of the drilled holes is adjusted at any time according to the actual situation on site, so that the rotary drilling rig can perform comprehensive crushing, and the purpose of improving the efficiency is achieved.
(4) Construction of the rotary drilling rig:
when the rotary drilling rig is used for constructing the non-hard bedrock on the upper part of the pile hole, the operation is carried out according to a conventional method.
And (3) fully crushing the hard bedrock part by using a cylindrical rock-socketed drill bit and a spiral rock-socketed drill bit under medium-pressure and low-drilling conditions, and fishing out. The single depth of advance can not exceed 0.4m, and the high-pressure quick drilling is strictly forbidden, which causes unnecessary loss to the drilling machine.
After pre-drilling by a down-the-hole drill, forming holes in pile holes No. 1, No. 2 and No. 3 by a rotary drilling drill. The time for forming the hole in the hole 1 is 5 hours and 20 minutes when the hole 17 meters are used, the time for forming the hole 2 is 5 hours and 30 minutes when the hole 17 meters are used, the time for forming the hole in the hole 3 is 5 hours when the hole 17 meters are used, and compared with a test hole and other operating piles, the hole is pre-drilled through a down-the-hole hammer, the time for rotary drilling and hole forming is saved by nearly 70 percent, the construction cost is reduced, and the construction efficiency is improved. Although the hole forming time of the rotary drilling rig of 20 minutes is saved for the hole No. 3, compared with the hole No. 1, the working load of the down-the-hole hammer of 34 meters is increased, the construction cost is increased, and waste is caused.
From the above analysis, it is desirable that the pre-drilled hole surface accounts for 40% to 60% of the cross-sectional area of the pile at the site. Pre-drilling is carried out according to the proportion in subsequent construction.
Example 1:
the field viaduct project of the Wulu wood Qi city is located on the Clay May west road of the Wulu wood Qi city, the pile foundation adopts a reinforced concrete rock-embedded cast-in-place pile with the design hole depth of 17-35 meters and the pile diameter of 1200mm and 1000mm, the rock-entering depth is 5-25 meters, according to a rock-soil investigation report provided by Xinjiang construction academy, the field stratum mainly comprises cobbles, fully weathered argillaceous siltstones, strongly weathered argillaceous siltstones, moderately weathered argillaceous siltstones and the like, and the construction difficulty is large. During pile testing, the short rock-socketed auger and the cylindrical rock-socketed drill are alternately used according to the previous construction experience, although the preset depth can be drilled, the construction time is too long, the single depth of advance in a rock stratum is not more than 5cm, the single pile hole forming time is 20 hours short and 86 hours long, the construction requirements can not be met far, and the construction of a bedrock section is determined to be carried out by adopting a down-the-hole hammer and a rotary drilling rig in a matched mode through research.
1. The principle of down-the-hole hammer hole distribution:
the pre-drilled holes are uniformly distributed in the drilled pile, the area shared by each hole is approximately equal, the basic principle of pre-drilled hole arrangement is that the ratio of the area of the drilled pile to the area of the pre-drilled hole is an important parameter of pre-drilled hole design, and through engineering practice, the area of the pre-drilled hole accounts for about 40% -60% of the area of the drilled pile.
2. The construction sequence is as follows:
firstly, marking the position of a pile hole on the original site by taking the center of the pile as an original point, then marking the position of a small hole according to a hole distribution principle, sequentially drilling the small hole to an appointed hole depth by a down-the-hole drill in a certain sequence, withdrawing the down-the-hole drill after all the small holes in the pile hole are finished, and then performing the rotary drilling according to a conventional construction procedure by the rotary drilling machine.
3. Preparing a down-the-hole drill for construction:
HR-160 rotary drilling rig, 1200mm and 1000mm rock-socketed short spiral drill bit, 1200mm and 1000mm cylinder rock-socketed drill bit, WT-300 automobile down-the-hole hammer drilling rig, 50 drill rods, 120mm percussion drill, 940 down-the-hole hammer, 140mm casing pipe and casing pipe centralizer
4. And (3) construction of a down-the-hole hammer:
during construction, a hard and flat working surface is firstly arranged to ensure that a drilling machine body is horizontal and a drill rod is vertical. And after the construction is started, the slow drill needs to be lightly pressed, the perpendicularity of the drill hole is checked at any time, the drill hole is adjusted in time to ensure that the drill hole cannot deviate out of the pile hole, and otherwise, the construction of the rotary drilling rig at the lower part is difficult greatly. The depth of each pre-drilled hole is required to exceed the designed depth of a pile hole by 100mm so as to ensure that the rotary drilling rig can carry out construction according to the designed depth, and the number of the drilled holes is adjusted at any time according to the actual situation on site so that the rotary drilling rig can carry out comprehensive crushing.
Aiming at the pile with the diameter of 1.2 meters in construction, a 120mm impactor is adopted on site, and according to the equal division principle, 4, 5 and 6 pre-drilled holes are correspondingly arranged in the hole No. 1, the hole No. 2 and the hole No. 3 respectively to check which comprehensive effect is optimal.
5. Construction of the rotary drilling rig:
when the rotary drilling rig is used for constructing non-hard bedrock on the upper part of a pile hole, the operation is carried out according to a conventional method, medium pressurization and low rotation speed are adopted for the bedrock part, a cylindrical rock-socketed drill bit and a spiral rock-socketed drill bit are utilized for carrying out comprehensive crushing and fishing out, and the depth of one-time footage cannot exceed 0.4 m. The high-pressure quick drilling is strictly forbidden, and unnecessary loss is caused to the drilling machine.
Claims (3)
1. A rock-entering pore-forming construction method of a rotary drilling rig assisted by a small-diameter down-the-hole hammer for a hard bedrock socketed pile in a high water level field is characterized by comprising the following steps: comprises the following steps of (a) carrying out,
s100, positioning a drilled pile position, and burying a pile casing by taking the center of the pile as an original point;
s200, placing a rotary drilling rig in place, constructing, drilling and taking soil, and injecting wall protection slurry into a hole;
s300, when the drilling is carried out to the bedrock surface, stopping drilling, lifting a drill rod, and withdrawing the rotary drilling rig from the construction pile position;
s400, arranging a plurality of down-the-hole pre-drilled holes in the drilled pile;
s500, manufacturing a small-diameter down-the-hole drill sleeve positioning frame according to the determined number of pre-drilled down-the-hole holes and the section size of the drilled pile, and installing the drill sleeve positioning frame in the drilled pile; the drill sleeve positioning frame comprises a frame body arranged in the drilled pile, and sleeve plate positioning holes which correspond to the down-the-hole pre-drilled holes one by one are arranged in the middle of the frame body;
s600, erecting a small-diameter down-the-hole hammer sleeve positioner on the pile casing, and sequentially placing down-the-hole hammer sleeves in the small-diameter down-the-hole hammer sleeve positioner;
s700, driving a wooden wedge between the down-the-hole hammer sleeve and a sleeve plate positioning hole on a drill sleeve positioning frame after the down-the-hole hammer sleeve is in place, pre-drilling a bedrock rock entry section hole by hole to a designed rock entry depth, and withdrawing the small-diameter down-the-hole hammer from a pile position after all down-the-hole pre-drilling holes are completed; pulling out the down-the-hole hammer sleeve and dismounting the small-diameter down-the-hole hammer sleeve positioner;
s800, putting the rotary drilling rig in place again, comprehensively crushing the rock stratum of the pre-drilled pile foundation rock entering section by using a cylindrical rock-socketed drill bit and a spiral rock-socketed drill bit, fishing out drilling slag, and finishing hole forming;
s900, pulling out the down-the-hole drill sleeve positioning frame and the down-the-hole drill sleeve;
s1000, cleaning holes of a lower guide pipe, and pouring concrete to form a pile after the cleaning is finished.
2. The high water level field hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig rock-entering pore-forming construction method according to claim 1 is characterized in that: in the step S400, the down-the-hole pre-drilled holes are uniformly distributed in the drilled pile, the area of each down-the-hole pre-drilled hole is equal, and the area of all the down-the-hole pre-drilled holes accounts for 40% -60% of the area of the drilled hole.
3. The high water level field hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig rock-entering pore-forming construction method according to claim 2, characterized in that: in the step S500, the diameter of the sleeve hole of the sleeve positioner is 0.1 to 1cm larger than the outer diameter of the sleeve of the down-the-hole hammer; wherein the positioning hole of the sleeve plate at the lower end of the sleeve positioning frame is 0.5cm +2mm larger than the outer diameter of the down-the-hole hammer sleeve; the sleeve positioning hole at the upper end of the sleeve positioning frame is larger than the outer diameter of the down-the-hole hammer sleeve by 1.0cm +2 mm; the sleeve positioning frame adopts different sizes according to the bedrock burial depth, and the height of the sleeve positioning frame can be 2 m-6 m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011279834.2A CN112411529A (en) | 2020-11-16 | 2020-11-16 | Rock-entering pore-forming method of hard bedrock socketed pile small-diameter down-the-hole hammer auxiliary rotary drilling rig |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113530443A (en) * | 2021-08-03 | 2021-10-22 | 淮南矿业(集团)有限责任公司 | Vertical drilling method for large-diameter life-saving hole |
| CN113982480A (en) * | 2021-10-18 | 2022-01-28 | 中电建十一局工程有限公司 | Hard rock stratum cast-in-situ bored pile pore-forming construction method |
| CN114704202A (en) * | 2022-03-23 | 2022-07-05 | 保利长大工程有限公司 | Construction method of bare rock geological pile foundation |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5232268A (en) * | 1992-04-01 | 1993-08-03 | Dynatec Mining Limited | Method of breaking a full face of rock for constructing shafts and tunnels |
| CN107143281A (en) * | 2017-05-18 | 2017-09-08 | 浙江省地矿建设有限公司 | The method of construction bored concrete pile |
| CN208734275U (en) * | 2018-08-28 | 2019-04-12 | 天津港航工程有限公司 | A kind of circular combined down-hole hammer drilling device suitable for Pile |
| CN110344400A (en) * | 2019-07-17 | 2019-10-18 | 北京建材地质工程有限公司 | The hard rock pore-forming construction technology of churning driven opportunity |
| CN110566114A (en) * | 2019-09-04 | 2019-12-13 | 深圳市工勘岩土集团有限公司 | Hard rock drilling pile-forming construction method of rotary excavating cluster type down-the-hole hammer |
| CN110685603A (en) * | 2019-09-17 | 2020-01-14 | 天津港航工程有限公司 | Offshore large-diameter steel pipe rock-socketed pile construction platform and construction method |
-
2020
- 2020-11-16 CN CN202011279834.2A patent/CN112411529A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5232268A (en) * | 1992-04-01 | 1993-08-03 | Dynatec Mining Limited | Method of breaking a full face of rock for constructing shafts and tunnels |
| US5232268B1 (en) * | 1992-04-01 | 1995-05-09 | Dynatec International Limited | Method of breaking a full face of rock for constructing shafts and tunnels |
| US5232268B2 (en) * | 1992-04-01 | 1996-10-15 | Dynatec International Limited | Method of breaking a full face of rock for constructing shafts and tunnels |
| CN107143281A (en) * | 2017-05-18 | 2017-09-08 | 浙江省地矿建设有限公司 | The method of construction bored concrete pile |
| CN208734275U (en) * | 2018-08-28 | 2019-04-12 | 天津港航工程有限公司 | A kind of circular combined down-hole hammer drilling device suitable for Pile |
| CN110344400A (en) * | 2019-07-17 | 2019-10-18 | 北京建材地质工程有限公司 | The hard rock pore-forming construction technology of churning driven opportunity |
| CN110566114A (en) * | 2019-09-04 | 2019-12-13 | 深圳市工勘岩土集团有限公司 | Hard rock drilling pile-forming construction method of rotary excavating cluster type down-the-hole hammer |
| CN110685603A (en) * | 2019-09-17 | 2020-01-14 | 天津港航工程有限公司 | Offshore large-diameter steel pipe rock-socketed pile construction platform and construction method |
Non-Patent Citations (2)
| Title |
|---|
| 尚增弟等: "深厚硬岩钻孔灌注桩大直径潜孔锤成桩综合施工技术", 《施工技术》 * |
| 祝振生: "硬岩深大基坑围护桩快速成孔施工", 《隧道建设》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113530443A (en) * | 2021-08-03 | 2021-10-22 | 淮南矿业(集团)有限责任公司 | Vertical drilling method for large-diameter life-saving hole |
| CN113530443B (en) * | 2021-08-03 | 2023-02-28 | 淮南矿业(集团)有限责任公司 | Vertical drilling method for large-diameter life-saving hole |
| CN113982480A (en) * | 2021-10-18 | 2022-01-28 | 中电建十一局工程有限公司 | Hard rock stratum cast-in-situ bored pile pore-forming construction method |
| CN114704202A (en) * | 2022-03-23 | 2022-07-05 | 保利长大工程有限公司 | Construction method of bare rock geological pile foundation |
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Application publication date: 20210226 |