A variable diameter plain concrete pile construction equipment and method

Abstract

The invention relates to a variable diameter plain concrete pile construction equipment and method. The equipment comprises a drilling rig and a spiral drill rod A, a drill bit is fixedly installed at the bottom of the spiral drill rod A, and a flange plate C is fixedly installed at the bottom of the power head of the drilling rig; the equipment also comprises a spiral drill rod B, an upper connecting piece, a lower connecting piece and a fixing device; the method comprises the steps of inserting the spiral drill rod A1 into the drill rod inner cavity of the spiral drill rod B2, drilling, pressure pouring concrete and lifting the drill. The construction equipment of the invention is simple to manufacture, easy to operate, reliable in performance and low in use cost. The method meets the design requirements for foundation bearing capacity and deformation settlement, and achieves the purpose of saving engineering cost to the greatest extent.

Description

Technical Field

[0001] The invention relates to variable diameter plain concrete pile construction equipment and method. Background Art

[0002] In recent years, there have been corresponding specifications for the treatment method of composite foundation of variable diameter plain concrete piles. The bearing capacity of a single pile of variable diameter plain concrete piles with the same concrete volume is greatly improved compared with that of piles with equal cross-section, which can greatly reduce the cost of foundation treatment. However, due to the immaturity of the corresponding mechanical drilling equipment on the market, some drilling tools have complex structures and high production costs, which makes the drilling rigs easy to be damaged during the construction process, increasing the maintenance cost and delaying the construction period; some drilling rigs have design defects that make it impossible to solve the problem of residual soil at the variable diameter during the construction process, thus failing to meet the design requirements, which has slowed the promotion of composite foundation of variable diameter plain concrete piles. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a variable diameter plain concrete pile construction device and method which is simple to manufacture, easy to operate, reliable in performance and low in use cost.

[0004] The present invention adopts the following technical scheme: the variable-diameter plain concrete pile construction equipment of the present invention comprises a drilling rig and a spiral drill rod A, a drill bit is fixedly installed at the bottom of the spiral drill rod A, and a flange plate C is fixedly installed at the bottom of the power head of the drilling rig; it also comprises a spiral drill rod B, an upper connecting piece, a lower connecting piece and a fixing device; the drill rods of the spiral drill rod A and the spiral drill rod B are both hollow, the length of the spiral drill rod A is 5-25m, and the length of the spiral drill rod B is 0.8-6m; the inner diameter of the drill rod of the spiral drill rod B is larger than the outer diameter of the spiral blade of the spiral drill rod A, and the spiral drill rod A is inserted into the inner cavity of the drill rod of the spiral drill rod B; the upper connecting piece is fixed to the top of the spiral drill rod A and the spiral drill rod B and cooperates with the flange plate C, one end of the fixing device is hinged to the drilling rig column, and the other end is fixedly installed on the spiral drill rod B; the spiral blade at the bottom of the spiral drill rod B is provided with a variable diameter section whose width changes from narrow to wide from bottom to top along the spiral direction.

[0005] The upper connecting piece of the construction equipment of the present invention comprises a flange A fixedly mounted on the top of the spiral drill rod A and a flange B fixedly mounted on the top of the spiral drill rod B, wherein the inner diameter of the flange B is greater than the outer diameter of the flange A; the flange A and the flange B are both matched with the flange C.

[0006] The lower connecting piece of the construction equipment of the present invention comprises a fixing hole arranged on the upper part of the spiral drill rod B, a U-shaped key inserted in the fixing hole, and a block fixed on the outer wall of the spiral drill rod A. The U-shaped key is engaged with the block when inserted into the fixing hole, and a groove is arranged on the outer wall of the block.

[0007] The construction equipment of the present invention has two groups of fixing holes, and the two U-shaped clamping keys are respectively inserted into the two groups of fixing holes to be in a vertical state.

[0008] The fixing device of the construction equipment of the present invention comprises an upper clamping hoop arranged on the upper part of the auger drill rod B and a lower clamping hoop arranged on the lower part of the auger drill rod B; the other ends of the upper clamping hoop and the lower clamping hoop are hinged to the drilling rig column, the upper clamping hoop cooperates with the outer wall of the auger drill rod B, and the lower clamping hoop cooperates with the spiral blade of the auger drill rod B.

[0009] The outer diameter of the spiral drill rod A of the construction equipment of the present invention is 0.18-0.58 m, and the outer diameter of the spiral drill rod B is 0.38 m-1.18 m.

[0010] The spiral blades at the bottom of the spiral drill rod B of the construction equipment of the present invention are in the shape of an inverted cone or trapezoid with an angle of 30° to 45° from bottom to top along the spiral direction, and the height of the inverted cone is 0.15m-0.8m.

[0011] The variable diameter plain concrete pile construction method of the present invention adopts the following steps: step 1, inserting the auger rod A into the drill rod inner cavity of the auger rod B, fixing the flange A on the top of the auger rod A with the flange C, the upper clamping hoop clamping the upper part of the drill rod of the auger rod B, and the lower clamping hoop clamping the spiral blade of the auger rod B; step 2, starting the drilling rig, and the auger rod A is drilled; when the auger rod A is drilled to the point where it is convenient for construction personnel to operate and connect the auger rod A and the auger rod B, the drilling rig stops, and the flange B and the flange C at the top of the auger rod B are fixed with bolts, at which time the flange A is located in the inner cavity of the flange B, and the upper clamping hoop and the lower clamping hoop for fixing the auger rod B are opened; step 3, starting the drilling rig, and the auger rod A and the auger rod B continue to drill synchronously until the designed variable diameter plain concrete pile pit is drilled, the drilling rig stops, and the flange B and the flange C are removed, and the auger rod B is retained in the variable diameter plain concrete pile pit; Step 4: Pour concrete into the inner cavity of the auger rod A, and the concrete is injected into the bottom of the variable diameter plain concrete pile pit from the drill bit; start the drilling rig, and the auger rod A rotates and lifts upward, and the soil in the variable diameter plain concrete pile pit is brought out from bottom to top by the spiral blades of the auger rod A; Step 5: When the concrete is poured to the inverted cone step, the position of the block of the auger rod A corresponds to the position of the fixing hole on the auger rod B, the drilling rig stops, and the two U-shaped keys are inserted into the fixing holes on one side and locked with the blocks, and then exposed from the fixing holes on the opposite side; Step 6: Start the drilling rig, and the auger rod A drives the auger rod B to lift upward synchronously and pour concrete at the same time. The auger rod B brings the soil at the inverted cone step and above out of the ground until the concrete is poured to the designed elevation; it is forbidden to lift the drill bit out of the concrete surface during the concrete pouring process; Step 7: After the variable diameter plain concrete pile pit is filled with concrete, the auger rod B is completely lifted to the ground, and the auger rod B is fixed to the drilling rig column with the upper and lower clamps. The two U-shaped clamps are pulled out, and the drilling rig is moved to the next pile position.

[0012] The positive effects of the present invention are as follows: the present invention can be modified on the basis of the original long spiral drilling machine, and the spiral drill rod B and the connecting device and the fixing device are simple to manufacture and low in cost. The present invention adopts a movable spiral drill rod B, so that the spiral drill rod A is lifted at the same time when the spiral drill rod B reaches the diameter change, which solves the problem of loose soil remaining at the step. Due to the large torque during drilling, the spiral drill rod A and the spiral drill rod B need to be connected by flanges. When lifting and grouting, the torque is small and a U-shaped key connection is used, which is convenient to install, saves operation time, and improves construction efficiency. The construction equipment of the present invention is simple to manufacture, easy to operate, reliable in performance and low in cost.

[0013] The construction method of the present invention increases the replacement rate of shallow single pile area by increasing the pile diameter of the upper part of the concrete pile, that is, changing the variable pile diameter and the inverted cone transition, so as to strengthen the foundation soil with relatively low shallow stratum strength in a targeted manner, and adopts a relatively small pile diameter in the lower part to meet the requirement for deformation, thereby achieving the goal of satisfying both the design requirement for foundation bearing capacity and the requirement for deformation settlement, and achieving the purpose of saving engineering cost to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Attached Figure 1 It is a schematic diagram of the structure of the present invention;

[0015] Attached Figure 2 Schematic diagram of the structure of the connection state of the auger rod A and auger rod B and the power head of the present invention; Figure 3 For attachment Figure 1 AA section structure diagram of Figure 4 For attachment Figure 1 BB section structure diagram; Attachment Figure 5 Schematic diagram of the structure of the spiral drill rod A in the drilling state of the present invention; Figure 6 Schematic diagram of the structure of the spiral drill rod B in the drilling state of the present invention; Figure 7 Schematic diagram of the structure of the spiral drill rod A in the drilling state of the present invention; Figure 8 Schematic diagram of the axonometric structure of the clamping block of the present invention; Fig. 9 For attachment Figure 7 Schematic diagram of CC section structure; Attachment Fig.10 It is a schematic diagram of the structure of the working completion state of the present invention. DETAILED DESCRIPTION

[0016] As attached Figure 1-10As shown, the present invention includes a drilling rig 10 and an auger rod A1, a drill bit 8 is fixedly installed at the bottom of the auger rod A1, and a flange C9 is fixedly installed at the bottom of the power head 13 of the drilling rig 10; it also includes an auger rod B2, an upper connecting piece, a lower connecting piece and a fixing device; the drill rods of the auger rod A1 and the auger rod B2 are both hollow, the length of the auger rod A1 is 5-25m, and the length of the auger rod B2 is 0.8-6m; the outer diameter of the auger rod A1 is 0.18-0.58m, and the outer diameter of the auger rod B2 is 0.38-1.18m. The inner diameter of the auger rod B2 is larger than the outer diameter of the spiral blade of the auger rod A1. The auger rod A1 is inserted into the inner cavity of the auger rod B2 and can rotate in the auger rod B2 during operation. The upper connecting piece is fixed to the top of the auger rod A1 and the auger rod B2 and cooperates with the flange C9. The lower connecting piece is arranged at the upper part of the auger rod B2 and the corresponding position of the auger rod A1. One end of the fixing device is hinged to the drilling rig column, and the other end is fixed to the auger rod B2 without affecting the drilling of the auger rod A1. The spiral blade at the bottom of the auger rod B2 is provided with a diameter-changing section whose width changes from narrow to wide from bottom to top along the spiral direction. In this embodiment, the spiral blade at the bottom of the auger rod B2 is in the shape of an inverted cone of 30°~45° from bottom to top along the spiral direction, and the height of the inverted cone is 0.15m-0.8m.

[0017] The upper connecting member of the present invention comprises a flange A3 fixedly mounted on the top of the auger rod A1 and a flange B4 fixedly mounted on the top of the auger rod B2, wherein the inner diameter of the flange B4 is greater than the outer diameter of the flange A3, and the flange A3 and the flange B4 are both matched with the flange C9, and at this time, the flange A3 is located in the inner cavity of the flange B4; the lower connecting member comprises a fixing hole 5 arranged on the upper part of the auger rod B2 drill rod, a U-shaped clamping key 6 inserted into the fixing hole 5, and a clamping block 7 fixed on the outer wall of the auger rod A1 drill rod, wherein a clamping groove 14 is arranged on the outer wall of the clamping block 7, and the length of the clamping block 7 is less than the diameter of the spiral blade of the auger rod A1, and the U-shaped clamping key 6 is clamped with the clamping groove 14 of the clamping block 7 when inserted into the fixing hole 5 to prevent the U-shaped clamping key 6 from moving; the fixing hole 5 There are two groups, and the two U-shaped clamping keys 6 are respectively inserted into the two groups of fixing holes 5 in a vertical state, so that the auger rod A and the auger rod B2 are firmly connected; the fixing device includes an upper clamping hoop 11 arranged on the upper part of the auger rod B2 drill rod and a lower clamping hoop 12 arranged on the lower part of the auger rod B2; the other ends of the upper clamping hoop 11 and the lower clamping hoop 12 are hinged on the column of the drilling rig 10, the upper clamping hoop 11 cooperates with the outer wall of the drill rod of the auger rod B2, and the lower clamping hoop 12 cooperates with the spiral blade of the auger rod B2.

[0018] As attached Figure 1-10As shown, the variable diameter plain concrete pile construction equipment of the present invention is used to construct the variable diameter plain concrete pile, and the following steps are adopted: Step 1, insert the auger rod A1 into the drill rod inner cavity of the auger rod B2, fix the flange A3 on the top of the auger rod A1 with the flange C9, the upper clamp 11 clamps the upper part of the drill rod of the auger rod B2, and the lower clamp 12 clamps the spiral blade of the auger rod B2; Step 2, start the drilling rig 10, and the auger rod A1 is drilled; when the auger rod A1 is drilled to the point where the construction personnel can conveniently operate and connect the auger rod A1 and the auger rod B2, the drilling rig 10 stops, fix the flange B4 on the top of the auger rod B2 with the flange C9 with bolts, and open the upper clamp 11 and the lower clamp 12 that fix the auger rod B2; Step 3, start the drilling rig 10, the auger rod A1 and the auger rod B2 continue to drill synchronously until the designed variable diameter plain concrete pile pit is drilled, the drilling rig 10 stops, the flange B4 and the flange C9 are removed, and the auger rod B2 is retained in the variable diameter plain concrete pile pit; Step 4, concrete is poured into the inner cavity of the auger rod A1, and the concrete is injected into the bottom of the variable diameter plain concrete pile pit from the drill bit 8; start the drilling rig 10, the auger rod A1 is lifted upward while rotating, and the soil in the variable diameter plain concrete pile pit is brought out from bottom to top by the spiral blades of the auger rod A1; Step 5, when the concrete is poured to the inverted cone step, the position of the block 7 of the auger rod A1 corresponds to the position of the fixing hole 5 on the auger rod B2, the drilling rig 10 stops, and the two U-shaped clamping keys 6 are respectively inserted from the fixing holes 5 on one side and are clamped with the clamping block 7 and then exposed from the fixing holes 5 on the opposite side; Step 6. Start the drilling rig 10. The auger rod A1 drives the auger rod B2 to be lifted upward synchronously while pouring concrete. The auger rod B2 brings the soil at and above the inverted cone step out of the ground until the concrete is poured to the designed elevation, which is not less than 50 mm above the designed elevation of the pile top. During the pouring of concrete, it is prohibited to lift the drill bit 8 out of the concrete surface. Step 7. After the variable-diameter plain concrete pile pit is filled with concrete, the auger rod B2 is completely lifted to the ground, and the auger rod B2 is fixed to the column of the drilling rig 10 with the upper clamp 11 and the lower clamp 12. The two U-shaped clamps 6 are pulled out, and the drilling rig 10 is moved to the next pile position.

[0019] The construction equipment of the present invention adopts a movable auger rod B2, so that the auger rod A1 is lifted at the same time when the auger rod B2 reaches the diameter change position, which solves the problem of loose soil remaining at the inverted cone step. Due to the large torque during drilling, the auger rod A1 and the auger rod B2 need to be connected by flanges. When lifting and pouring concrete, the torque is small and the U-shaped card key 6 is used for connection. The installation is convenient, the operation time is saved, and the construction efficiency is improved.

[0020] The construction method of the present invention increases the replacement rate of shallow single pile area by increasing the pile diameter of the upper part of the concrete pile, that is, changing the variable pile diameter and the inverted cone transition, so as to strengthen the foundation soil with relatively low shallow stratum strength in a targeted manner, and adopts a relatively small pile diameter in the lower part to meet the requirement for deformation, thereby achieving the goal of satisfying both the design requirement for foundation bearing capacity and the requirement for deformation settlement, and achieving the purpose of saving engineering cost to the greatest extent.

Claims

1. A method for constructing variable diameter plain concrete piles, characterized in that: The invention comprises a variable diameter plain concrete pile construction device, the variable diameter plain concrete pile construction device comprises a drilling machine (10) and a spiral drill rod A (1), a drill bit (8) is fixedly installed at the bottom of the spiral drill rod A (1), and a flange plate C (9) is fixedly installed at the bottom of a power head (13) of the drilling machine (10); the device also comprises a spiral drill rod B (2), an upper connecting piece, a lower connecting piece and a fixing device; the drill rods of the spiral drill rod A (1) and the spiral drill rod B (2) are both hollow, the length of the spiral drill rod A (1) is 5-25m, and the length of the spiral drill rod B (2) is 0.8-6m; the inner diameter of the spiral drill rod B (2) is larger than the outer diameter of the spiral blade of the spiral drill rod A (1), and the spiral drill rod A (1) is inserted into the inner cavity of the drill rod of the spiral drill rod B (2); The upper connecting piece is fixed to the top of the auger rod A (1) and the auger rod B (2) and cooperates with the flange C (9); one end of the fixing device is hinged to the column of the drilling rig (10), and the other end is fixedly mounted on the auger rod B (2); The spiral blade at the bottom of the spiral drill rod B (2) is provided with a variable diameter section whose width changes from narrow to wide from bottom to top along the spiral direction; The upper connecting member comprises a flange A (3) fixedly mounted on the top of the auger rod A (1) and a flange B (4) fixedly mounted on the top of the auger rod B (2), wherein the inner diameter of the flange B (4) is greater than the outer diameter of the flange A (3); The flange A (3) and the flange B (4) are both matched with the flange C (9); The lower connecting member comprises a fixing hole (5) provided on the upper part of the drill rod of the spiral drill rod B (2), a U-shaped clamping key (6) inserted into the fixing hole (5), and a clamping block (7) fixed on the outer wall of the drill rod of the spiral drill rod A (1), wherein the U-shaped clamping key (6) is clamped with the clamping block (7) when inserted into the fixing hole (5), and a clamping groove (14) is provided on the outer wall of the clamping block (7); The fixing device comprises an upper clamp (11) arranged on the upper part of the drill rod of the auger drill rod B (2) and a lower clamp (12) arranged on the lower part of the auger drill rod B (2); the other ends of the upper clamp (11) and the lower clamp (12) are both hinged to a column of a drilling rig (10); the upper clamp (11) cooperates with the outer wall of the drill rod of the auger drill rod B (2), and the lower clamp (12) cooperates with the spiral blade of the auger drill rod B (2); The construction method of variable diameter plain concrete piles adopts the following steps: Step 1: insert the auger rod A (1) into the inner cavity of the auger rod B (2), fix the flange A (3) on the top of the auger rod A (1) to the flange C (9), clamp the upper clamp (11) tightly on the upper part of the auger rod B (2), and clamp the lower clamp (12) tightly on the spiral blade of the auger rod B (2); Step 2: Start the drilling machine (10) and drill the auger rod A (1); when the auger rod A (1) is drilled to a point where the construction personnel can easily operate to connect the auger rod A (1) and the auger rod B (2), the drilling machine (10) stops, and the flange B (4) at the top of the auger rod B (2) is fixed to the flange C (9) with bolts. At this time, the flange A (3) is located in the inner cavity of the flange B (4), and the upper clamp (11) and the lower clamp (12) fixing the auger rod B (2) are opened; Step 3, start the drilling machine (10), and the auger rod A (1) and the auger rod B (2) continue to drill synchronously until the designed variable diameter plain concrete pile pit is drilled, the drilling machine (10) stops, the flange plate B (4) and the flange plate C (9) are removed, and the auger rod B (2) is retained in the variable diameter plain concrete pile pit; Step 4: concrete is poured into the inner cavity of the spiral drill rod A (1), and the concrete is injected into the bottom of the variable diameter plain concrete pile pit from the drill bit (8); the drilling machine (10) is started, and the spiral drill rod A (1) is lifted upward while rotating, and the soil in the variable diameter plain concrete pile pit is brought out from bottom to top by the spiral blades of the spiral drill rod A (1); Step 5: When the concrete is poured to the inverted cone step, the position of the block (7) of the auger rod A (1) corresponds to the position of the fixing hole (5) on the auger rod B (2), the drilling machine (10) stops, and two U-shaped clamping keys (6) are respectively inserted from the fixing holes (5) on one side and locked with the block (7) so as to emerge from the fixing holes (5) on the opposite side; Step 6: Start the drilling machine (10), the auger rod A (1) drives the auger rod B (2) to be lifted up synchronously and concrete is poured at the same time, the auger rod B (2) brings the soil at and above the inverted cone step out of the ground until the concrete is poured to the designed elevation; during the process of pouring concrete, it is forbidden to lift the drill bit (8) out of the concrete surface; Step 7: After the variable diameter plain concrete pile pit is filled with concrete, the auger rod B (2) is completely lifted to the ground, the auger rod B (2) is fixed to the column of the drilling rig (10) by using the upper clamp (11) and the lower clamp (12), the two U-shaped clamps (6) are pulled out, and the drilling rig (10) is moved to the next pile position.

2. A variable diameter plain concrete pile construction method according to claim 1, characterized in that: The fixing holes (5) are in two groups, and the two U-shaped clamping keys (6) are respectively inserted into the two groups of fixing holes (5) to be in a vertical state.

3. The variable diameter plain concrete pile construction method according to claim 1, characterized in that: The outer diameter of the auger rod A (1) is 0.18-0.58 m, and the outer diameter of the auger rod B (2) is 0.38 m-1.18 m.

4. The construction method of a variable diameter plain concrete pile according to claim 1, characterized in that: The spiral blades at the bottom of the spiral drill rod B (2) are in the shape of an inverted cone with an angle of 30° to 45° from bottom to top along the spiral direction, and the height of the inverted cone is 0.15m to 0.8m.

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