Efficient guide hole inserting and driving method for rock-entering steel sheet pile

Abstract

The invention discloses an efficient guide hole inserting and driving method for a rock-entering steel sheet pile. The method comprises the following steps that S1, a cofferdam area is constructed, a construction platform is built, and a lowering system is installed; s2, the ring beam is lowered through a lowering system; s3, hole guiding construction is conducted, hole guiding is conducted through hole guiding equipment, a set of holes are guided from the corner end of the upstream small pile mark side, and then hole guiding is sequentially completed according to the clockwise sequence; and S4, steel sheet pile inserting and driving construction is conducted, specifically, the steel sheet piles are sequentially inserted and driven to the designed elevation along the guide holes with the ring beam as a guide frame. The construction method is suitable for the engineering geological conditions that the cofferdam depth is large and a main rock stratum is strongly-weathered argillaceous siltstone, the perpendicularity of inserting and driving of the steel sheet pile and the buried depth are effectively controlled, hole guiding is conducted in the mode that a rotary excavating drill and a double-flat-head single-screw drill bit are adopted to drill the weathered rock into pieces (not taken out), and the construction efficiency is ensured; a ring beam is lowered to serve as a guide frame structure to guide and limit drilling guide holes and steel sheet pile inserting and driving, so that the perpendicularity is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of cofferdam construction, in particular to a method for efficiently drilling and driving a steel sheet pile into a rock. Background Art

[0002] With the development of society, road and bridge projects, as basic infrastructure projects, are an important part of urban transportation networks. Highway bridges and viaducts often use bridge piers as supports. Therefore, the construction of bridge piers is one of the keys to road and bridge projects. In bridge projects involving water, cofferdam construction is often required, and a certain area is built in the water-related area for the construction of pier foundations. There are many traditional cofferdam construction methods. In the actual construction process, in addition to the conventional cofferdam structure and cofferdam construction process, it is also necessary to comprehensively consider the hydrogeological conditions of the construction area, and make some targeted improvements and optimizations to the cofferdam structure and cofferdam construction process methods to ensure the smooth progress of cofferdam construction. Steel sheet pile cofferdam is a common cofferdam construction method now. Its preliminary work is to insert steel sheet piles into the deep layer of the riverbed as the cofferdam support foundation. In the actual steel sheet pile insertion and driving construction process, based on the geological conditions of the riverbed, it may have a substantial impact on the insertion and driving of steel sheet piles. For example, it is difficult for steel sheet piles to penetrate the rock layer, which makes it difficult for steel sheet piles to reach the design elevation. Therefore, a corresponding high-efficiency rock-entering steel sheet pile driving method is needed to solve this problem and ensure the quality and progress of the project. The existing rock-entering steel sheet pile driving method has not been able to solve this technical problem well and needs further improvement and optimization. Summary of the invention

[0003] In view of the above problems, the present invention provides a method for efficiently drilling and driving a steel sheet pile into a rock, comprising the following steps:

[0004] S1, construction of the cofferdam area, building of the construction platform, and installation of the lowering system;

[0005] S2, lowering the ring beam by the lowering system;

[0006] S3, hole guiding construction, using hole guiding equipment to guide holes, guide a group of holes from the corner end of the upstream small pile number side, and then complete the hole guiding in a clockwise order;

[0007] S4, steel sheet pile driving construction, the steel sheet piles are driven in sequence along the guide hole and using the ring beam as a guide frame to the designed elevation, starting from the corner points of the cofferdam on the upstream side and proceeding symmetrically to both sides, closing on the downstream side, and completing the guide hole driving of the steel sheet piles.

[0008] As a further explanation of the present invention, the hole-drilling equipment includes a rotary drill and a double-flat-head single-screw drill bit. During the drilling process, the weathered rock is drilled into pieces without being removed, and the soil or rock layer is drilled loose in situ. The purpose is to reduce the supporting force at the bottom of the steel sheet pile during subsequent steel sheet pile insertion to ensure construction efficiency. Compared with the existing conventional steel pipe pile process, it is more efficient and economical.

[0009] Furthermore, the ring beam includes several layers of ring beams from top to bottom, wherein several layers of ring beams are designed to be located above the riverbed surface, and several layers of ring beams are designed to be located below the riverbed surface. The several layers of ring beams designed to be located above the riverbed surface are used as the guide frame to guide and limit the insertion of the steel sheet piles in the vertical direction.

[0010] Furthermore, in the step S1, group marking is performed on the construction platform to identify the positional relationship between the guide holes and the steel sheet piles.

[0011] Furthermore, in step S3, after the hole-guiding device guides the hole to a certain depth, verticality control of the hole-guiding is performed.

[0012] Furthermore, the specific control method of the verticality hole-guiding control is that the hole-guiding device performs a rod-lifting operation after drilling downward a unit distance.

[0013] Furthermore, in the step S4, the steel sheet piles are driven in close proximity to the guide holes, and when the steel sheet piles cannot reach the designed elevation, the holes are re-drilled at that position until the steel sheet piles are driven in to the designed elevation.

[0014] Furthermore, after the steel sheet piles are inserted and driven completely, the entire steel sheet piles are re-vibrated.

[0015] Furthermore, in the step S4, when it is difficult to close the steel sheet piles, they are closed by using special-shaped steel sheet piles.

[0016] Furthermore, in the step S4, the process of driving the first steel sheet pile also includes using a total station to control the verticality of the driving, and the subsequent steel sheet piles are driven symmetrically on both sides with the first steel sheet pile as a reference.

[0017] The ring beam includes several layers of ring beams from top to bottom, wherein several layers of ring beams are designed to be located above the riverbed surface, and several layers of ring beams are designed to be located below the riverbed surface. The several layers of ring beams designed to be located above the riverbed surface are used as the guide frame to guide and limit the insertion of the steel sheet piles in the vertical direction.

[0018] The construction method of the present invention is suitable for engineering geological conditions where the cofferdam is deep and the main rock layer is strongly weathered muddy siltstone, and can effectively control the verticality and the depth of penetration of steel sheet piles. Specifically, the weathered rock is broken (without taking it out) by a rotary drill + a double flat-head single-screw drill bit to guide the hole, thereby ensuring the construction efficiency. On the other hand, a pre-supported ring beam is used as a guide, and the ring beam is lowered as a guide frame structure to guide and limit the drilling of the guide hole and the insertion of the steel sheet pile, so that the insertion and sinking are slow, and the process correction is strengthened to ensure the verticality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart of the high-efficiency hole-driving method for rock-entering steel sheet piles of the present invention;

[0020] Figure 2 This is a schematic diagram of the relationship between the steel sheet pile and the guide hole in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the ring beam guide according to an embodiment of the present invention;

[0022] Figure 4 It is a schematic diagram of the driving direction of steel sheet piles according to an embodiment of the present invention.

[0023] Figure numerals: construction platform 1, casing 2, guide hole 3, steel sheet pile 4, lock buckle 401, fourth ring beam 5, third ring beam 6, second ring beam 7, first ring beam 8, corbel 9, wire rope 10. DETAILED DESCRIPTION

[0024] Example:

[0025] The following is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0026] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] like Figure 1-4 As shown, a method for efficiently drilling and driving a steel sheet pile into a rock comprises the following steps:

[0028] S1, construction in the cofferdam area, building a construction platform 1, and installing a lowering system. Specifically, the lowering system in this embodiment includes a winch and a steel wire rope 10 installed on the casing 2;

[0029] S2, lowering the ring beam by the lowering system;

[0030] S3, construction of lead hole 3, lead hole 3 by using the lead hole equipment, lead a group of holes at the corner end from the upstream small pile number side, and then complete the lead holes in a clockwise order;

[0031] S4, the steel sheet pile 4 is driven in, and the steel sheet pile is driven in sequence along the guide hole and to the designed elevation using the ring beam as a guide frame, starting from the corner points of the cofferdam on the upstream side and proceeding symmetrically to both sides, closing at the downstream side, and completing the guide hole driving of the steel sheet pile.

[0032] The construction method of the present invention is suitable for engineering geological conditions where the cofferdam depth is deep and the main rock layer is strongly weathered muddy siltstone, and can effectively control the verticality and the depth of penetration of steel sheet piles. Specifically, the weathered rock is broken (without taking it out) by using a rotary drill + a double flat-head single-screw drill bit to drill the weathered rock to pieces to guide the hole. In a specific embodiment, the hole-guiding equipment uses a rotary drill with a model between 280 and 360, and uses Φ80cm and Φ100cm spiral drill bits to drill to a designed pile bottom elevation of -7.0m. The drill residue is not taken out, and the soil layer or rock layer is loosened in situ, so as to reduce the bearing force of the bottom of the steel sheet pile during subsequent steel sheet pile insertion and ensure construction efficiency.

[0033] On the other hand, in specific applications, the ring beam of the pre-support method is used as a guide. By lowering the ring beam as a guide frame structure, the drilling of the lead hole and the insertion of the steel sheet pile are guided and restricted, and the insertion and sinking are carried out slowly to strengthen the process correction to ensure verticality. For details, see the attached Figure 3 As shown, the ring beam of this embodiment includes several layers of ring beams from top to bottom, wherein several layers of ring beams are designed to be located above the riverbed surface, and several layers of ring beams are designed to be located below the riverbed surface. The several layers of ring beams designed to be located above the riverbed surface are used as the guide frame to guide and limit the insertion of the steel sheet piles in the vertical direction. After the construction platform 1 is erected, the ring beam is assembled on the platform. First, the long side and the short side of the fourth ring beam 5 are processed to the designed length on the trestle, and then the hoisting equipment is used to lower it to the construction platform 1 for assembly. The order of lowering: first lower the long side (downstream); then lower the short side (large pile number side); then lower the short side (small pile number side); finally lower the long side (upstream side). After all four sides of the ring beam are lowered and the measurement group has completed the data review, the nodes, internal supports, and limit I-beams are installed. In order to ensure that the guide hole is completed, the first ring beam 8 and the second ring beam 7 are used as guide frames to insert steel sheet piles; the first ring beam 8 and the second ring beam 7 are connected into a whole, and the whole is lowered to the position of the first ring beam 8 at the movable corbel 9 by a winch, and then the corbel is reinforced before the steel sheet piles are inserted.

[0034] In step S1, group marking is performed on the construction platform to identify the positional relationship between the guide holes and the steel sheet piles. Figure 2 As shown, in this embodiment, a colored note is first drawn on the supporting trestle in a group of 5 holes at a distance of 80 cm, and a rotary drilling device is used to first lead a group of holes from the corner end of the upstream small pile side, and then the holes are led in a clockwise direction.

[0035] In step S3, after the hole-guiding device guides the hole to a certain depth, vertical hole-guiding control is performed. To ensure the verticality of the hole during the hole-guiding process, it is necessary to make timely adjustments on site according to the sensor display of the rotary drill; as a feasible implementation method, the vertical hole-guiding control is specifically controlled in such a way that the hole-guiding device performs a rod-lifting operation after drilling a unit distance downward. For example, in actual application, when drilling to about 18m, the rod-lifting operation is performed every 30cm or so when drilling downward, so as to ensure verticality.

[0036] In the step S4, when the steel sheet piles are difficult to insert and cannot reach the designed elevation during the construction process, the hole-guiding device is used to repair the hole until the steel sheet piles are inserted and driven to the designed elevation. The specific insertion and driving steps of the steel sheet piles include: the first step: applying butter on the steel sheet piles to reduce the friction between the steel sheet piles; and when inserting the next steel sheet pile, the operator aligns the lock 401 of the steel sheet pile with the previous steel sheet pile; the second step: during the process of inserting and driving the steel sheet piles, it is necessary to continuously cool the contact surface between the steel sheet piles with cold water to reduce the heat between the steel sheet piles. In the preferred embodiment, after the steel sheet piles are fully inserted and driven, the entire steel sheet pile is re-vibrated; the third step: every 5 steel sheet piles are reinforced. After every 5 steel sheet piles are inserted and driven, the offset adjustment is performed, and the cycle continues.

[0037] During the driving process of steel sheet piles, the lower end of the steel sheet pile is squeezed upward, the gap between the locking mouths of the steel sheet piles is large, and the upper end will always tilt away from the first steel sheet pile. Therefore, a plumb bob must be used to control the inclination of the steel sheet pile within 1% for every 4 to 5 steel sheet piles. If the inclination exceeds the limit, the deviation should be corrected (the one-time correction should not be too much, so as to avoid the locking mouth getting stuck and affecting the driving of the next steel sheet pile). When the steel sheet pile is too offset, the only way to gradually reduce the displacement is to use multiple corrections. If the correction is difficult due to the hard soil, a four-pulley group can be used for correction. After the steel sheet piles are driven, in order to facilitate the personnel to go up and down; the upper and lower channels are arranged along the inner wall of the steel sheet piles. They are made of 10[channel steel and Φ48×3.5mm welded pipes. The upper end is hung on the top surface of the platform. To prevent the ladder from swinging too much, temporary welding can be done on the inner side of the middle.

[0038] The two piles at the closing position should be one high and one low. When closing, the upper part is often small and the lower part is large (there is soil squeezing at the lower end, and the upper end is free). At this time, two four-way pulleys can be used to pull them apart until the distance between the tops of the piles on both sides of the closing pile is equal to the width of the steel sheet pile. When they are close to parallel, the closing piles are inserted and driven to the designed elevation. As shown in the attached figure, there are four faces in the rectangular cofferdam. Each steel sheet pile driven must be perpendicular to the normal and tangent direction of the guide frame. The closing is chosen near the corner pile. If there is a difference in distance, the distance between the adjacent side of the closing side and the guide frame can be adjusted. In order to prevent the two piles at the closing position from being in the same plane, the direction of the corner pile must be adjusted so that the locking mouth of one side is kept as parallel as possible with the locking mouth of the opposite steel sheet pile. When it is difficult to close the steel sheet piles, they are closed by special-shaped steel sheet piles. The special-shaped steel sheet piles are made according to the measured dimensions.

[0039] In order to ensure the accuracy of the driving position, the first steel sheet pile is the key to the driving. Specifically, in step S4, on the one hand, the first ring beam 8 and the second ring beam 7 are used as guide frames, and the hook is slowly lowered while driving; on the other hand, a total station is used to control the verticality of the driving to ensure that the steel sheet pile is driven correctly and straight. The subsequent steel sheet pile driving takes the first steel sheet pile as a reference and drives the steel sheet piles symmetrically on both sides.

[0040] The above only describes the preferred embodiments of the present invention, but it cannot be understood as limiting the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to be changed. In short, all changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

Claims

1. A method for efficiently drilling and driving steel sheet piles into rock, characterized in that: The following steps are involved: S1, construction of the cofferdam area, building of the construction platform, and installation of the lowering system; S2, lowering the ring beam by the lowering system; S3, hole guiding construction, using hole guiding equipment to guide holes, guide a group of holes from the corner end of the upstream small pile number side, and then complete the hole guiding in a clockwise order; S4, steel sheet pile driving construction, the steel sheet piles are driven in sequence along the guide hole and using the ring beam as a guide frame to the designed elevation, starting from the corner points of the cofferdam on the upstream side and proceeding symmetrically to both sides, closing on the downstream side, and completing the guide hole driving of the steel sheet piles.

2. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: The hole-guiding device comprises a rotary drill and a double-flat-head single-screw drill bit, and weathered rocks are drilled into pieces and not taken out during the hole-guiding process.

3. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: The ring beam includes several layers of ring beams from top to bottom, wherein several layers of ring beams are designed to be located above the riverbed surface, and several layers of ring beams are designed to be located below the riverbed surface. The several layers of ring beams designed to be located above the riverbed surface are used as the guide frame to guide and limit the insertion of the steel sheet piles in the vertical direction.

4. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: In the step S1, group marking is performed on the construction platform to identify the positional relationship between the guide holes and the steel sheet piles.

5. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: In step S3, after the hole-guiding device guides the hole to a certain depth, verticality control of the hole-guiding is performed.

6. The high-efficiency rock-entering steel sheet pile driving method according to claim 5 is characterized in that: The specific control method of the verticality hole-guiding control is that the hole-guiding equipment performs a rod-lifting operation after drilling downward a unit distance.

7. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: In step S4, the steel sheet piles are driven in close proximity to the lead holes. When the steel sheet piles cannot reach the designed elevation, the holes are re-drilled at that position until the steel sheet piles are driven in to the designed elevation.

8. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized by: After the steel sheet piles are driven in, the entire steel sheet piles are re-vibrated.

9. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: In the step S4, when it is difficult to close the steel sheet piles, they are closed by using special-shaped steel sheet piles.

10. The high-efficiency rock-entering steel sheet pile driving method according to claim 1 is characterized in that: In the step S4, the process of driving the first steel sheet pile also includes using a total station to control the verticality of the driving, and the subsequent steel sheet piles are driven symmetrically on both sides with the first steel sheet pile as a reference.

Images