Special-shaped rammer for pile forming

Abstract

The utility model designs a special-shaped rammer for pile forming. The special-shaped rammer for pile forming is composed of an upper hammer head and a lower hammer rod. The mass of the upper hammer head is more than 60% of the total mass of the special-shaped rammer; the lower hammer rod is structurally a single-layer steel pipe or a double-layer steel pipe or a solid steel column, and the bottom end of the lower hammer rod is a flat bottom; the upper hammer head and the lower hammer rod can be quickly assembled and disassembled or directly welded into a whole; the specification of the lower hammer rod is matched according to a prefabricated pipe pile or a wall protection steel pipe used in actual construction, and when the prefabricated pipe pile or the wall protection steel pipe is long, the lower hammer rod can be rapidly connected and disassembled in a multi-section combination mode, so that the length of the lower hammer rod is increased or reduced, and the construction requirement is met.

Description

Technical Field

[0001] The present invention relates to a device for constructing a foundation pile, in particular to a special-shaped rammer for pile forming. Background Art

[0002] In building construction, the construction of the foundation and the subgrade is the key to ensuring the safety of the building. Foundation piles are a commonly used means for ground treatment. There are various types of foundation piles, each with its own characteristics. In the construction of foundation piles, a heavy rammer is a relatively commonly used construction tool, especially in the construction of carrier piles, compaction piles, etc. For example, the carrier pile is a pile foundation construction technology developed in recent years. It uses a cement-sand mixture as a filler, and then uses a heavy rammer to repeatedly ram the filler to form a carrier at the bottom of the pile to improve the bearing capacity of the pile. The invention and innovation of the carrier pile technology have been widely applied in the construction engineering field, creating relatively significant social and economic benefits.

[0003] Currently, the most commonly used rammer for carrier piles is a slender rammer weighing 3.5 tons. The weight of the rammer used in precast pipe piles is even smaller, generally 2-3 tons. In multiple tests and constructions, it has been found that when using a rammer of this weight for construction, when compacting the filler in a relatively good soil layer, it is easy to have a situation where the filler volume is very small and the three-strike penetration control requirement is quickly reached. However, in subsequent inspections, it is found that the bearing capacity of the pile is not high, which does not match the theoretical bearing capacity corresponding to the three-strike penetration. After searching for the reasons in many ways, it is found that the weight of the ramming tool is insufficient, and the ramming energy generated is relatively small, which cannot completely overcome the resistance of the soil at the pile tip. The resistance is even greater when compacting the filler, so there is a situation where the filler volume is small and a good compaction effect cannot be formed, but it is easy to meet the penetration requirement. This "meeting the penetration standard" is not a real compliance. In fact, the bearing capacity corresponding to the penetration standard has not been achieved. At the same time, when compacting the filler in a relatively soft soil layer, it is easy to have a situation where the number of ramming times is relatively large, the filler volume is very large, but the three-strike penetration standard cannot be reached all the time. Sometimes, even when the filler volume reaches 2 cubic meters, the penetration still cannot meet the standard. The reason for this situation is also that the ramming energy is relatively small, and the number of ramming times has to be increased. However, the more the number of ramming times, the greater the disturbance to the soil at the pile tip, and instead, the soil is rammed into a rubbery soil and loses its original bearing capacity, resulting in the failure of the construction. However, to solve these problems, simply and directly increasing the mass of the rammer is not feasible, because the adaptability of the construction equipment must be considered. It is restricted by the height, stiffness, lifting and other capabilities of the construction equipment, and the adaptability to the construction pile type also needs to be considered, and it is closely related to the pile length, pile diameter, pile body material, etc. Summary of the Utility Model

[0004] The utility model designs a special-shaped tamping hammer for pile forming, which consists of an upper hammer head and a lower hammer rod; the upper hammer head is made of steel or cast iron, and its mass is more than 60% of the total mass of the special-shaped tamping hammer; the diameter of the lower hammer rod is smaller than that of the upper hammer head, and its structure is a single-layer steel pipe or a double-layer steel pipe or a solid steel column, and its bottom end is a flat bottom; the upper hammer head and the lower hammer rod can be quickly assembled and disassembled by using one of the connection methods of bolts, pins, screw threads, and threaded sleeves, or directly welded into one body; the specifications of the lower hammer rod are adapted according to the precast pipe piles or retaining wall steel pipes used in actual construction. It is required that its diameter is 3-5 cm smaller than the central hole diameter of the precast pipe pile or the inner diameter of the retaining wall steel pipe, and its length is required to be greater than the length of the precast pipe pile or the retaining wall steel pipe; when the precast pipe pile or the retaining wall steel pipe is relatively long, the lower hammer rod can be quickly connected and disassembled by using a multi-section combination method to increase or decrease its length to meet the construction needs.

[0005] Preferably, guiding arms or guiding grooves are provided on two sides of the upper hammer head of the special-shaped tamping hammer for connecting the vertical support of the pile driver, and a lifting point is provided at the center position of the top of the upper hammer head for connecting the lifting device of the pile driver; during construction, the lower hammer rod of the special-shaped tamping hammer passes through the central hole of the precast pipe pile or the inner cavity of the retaining wall steel pipe. After the special-shaped tamping hammer is lifted to a certain height by the lifting device of the pile driver, the special-shaped tamping hammer makes a free-fall motion along the vertical support of the construction equipment, and the upper hammer head generates the main tamping energy above the precast pipe pile or the retaining wall steel pipe, and the bottom end of the lower hammer rod generates an impact force.

[0006] Preferably, the shape of the upper hammer head of the special-shaped tamping hammer is cylindrical or square-columnar or multi-sided columnar.

[0007] Preferably, one or more diameter-expanded sections are provided at the bottom or the middle part of the lower hammer rod of the special-shaped tamping hammer to prevent the hammer from being sucked.

[0008] Preferably, when the structure of the lower hammer rod is a single-layer steel pipe or a double-layer steel pipe, one or several materials such as lead, steel slag, stone powder, crushed stone, sand, concrete, and mortar are filled into the steel pipe to increase its mass.

[0009] Preferably, the lower hammer rod can be quickly connected and disassembled by using a multi-section combination method, and its connection and disconnection methods adopt one of the connection methods of bolts, pins, screw threads, and threaded sleeves.

[0010] The special-shaped ramming hammer for pile forming of the present utility model has the following characteristics and advantages: ① Compared with the commonly used slender heavy hammer, the special-shaped ramming hammer combines the upper hammer head and the lower hammer rod, which can significantly increase the overall mass of the hammer, generally 4-10 tons, without increasing the overall length of the hammer; ② It has lower requirements for the height, stiffness and structure of the construction equipment, and the commonly used medium and small-sized equipment in society can be used without improvement; ③ It is especially suitable for the construction of pile types such as carrier piles and compaction piles. While significantly increasing the ramming energy, it is not restricted by the length, diameter and inner diameter of precast pipe piles or retaining steel pipes; ④ The structure is clear and easy to process. The upper hammer head and the lower hammer rod can be quickly connected and disassembled, which is convenient for construction and transportation. The lower hammer rod can also be quickly connected and disassembled, and its length can be increased or decreased according to the specific situation on site to meet the actual construction needs of different projects. Brief Description of the Drawings

[0011] Figure 1 is a side view of an embodiment of the special-shaped ramming hammer for pile forming; Figure 2 is a schematic diagram of the construction of a precast pipe pile carrier pile by the special-shaped ramming hammer embodiment; wherein, 1 - upper hammer head, 2 - lower hammer rod, 3 - side guide arm, 4 - lifting point, 5 - precast pipe pile. Detailed Description of the Invention

[0012] Figure 1 is a side view of the special-shaped ramming hammer, as Figure 1 shown, the special-shaped ramming hammer for pile forming is composed of two parts: an upper hammer head 1 and a lower hammer rod 2; the upper hammer head 1 is a steel circular cylinder with a diameter of 1 m and a mass of 4.5 tons, and the lower hammer rod 2 is a single-layer thick-walled steel pipe structure with a diameter of 260 mm and a weight of 1.2 tons. The bottom end of the lower hammer rod 2 is closed and flat; the upper hammer head 1 and the lower hammer rod 2 are connected by bolts and can be quickly assembled and disassembled; two side guide arms 3 are respectively arranged on two sides of the upper hammer head 1, which can be used to connect the vertical support of the construction equipment, and a lifting point 4 is arranged at the center position of the top of the upper hammer head 1, which can be used to connect the lifting device of the construction equipment.

[0013] Figure 2 is a schematic diagram of the construction of a precast pipe pile carrier pile by the special-shaped ramming hammer, as Figure 2As shown in the figure, the lower hammer rod 2 of the special-shaped rammer passes through the central hole of the precast pipe pile 5. The diameter of the lower hammer rod 2 is more than 3 cm smaller than the diameter of the central hole of the precast pipe pile 5. The lower hammer rod 2 is composed of two single-layer steel pipes connected by pins, and its total length is more than 50 cm longer than the length of the precast pipe pile to ensure that the upper hammer head 1 does not touch the top of the precast pipe pile 5 when falling. During construction, the lower hammer rod 2 of the special-shaped rammer passes through the central hole of the precast pipe pile 5. After the special-shaped rammer is lifted to a certain height by the lifting device of the construction equipment, the special-shaped rammer falls in free fall. The upper hammer head 1 generates the main ramming energy above the precast pipe pile 5, and the bottom end of the lower hammer rod 2 generates an impact force to ram the bottom soil or filler.

Claims

1. A special-shaped rammer for pile forming, characterized in that, The special-shaped rammer consists of an upper hammer head and a lower hammer rod; the upper hammer head is made of steel or cast iron, and its mass is more than 60% of the total mass of the special-shaped rammer; the diameter of the lower hammer rod is smaller than that of the upper hammer head, and its structure is a single-layer steel pipe or a double-layer steel pipe or a solid steel column, and its bottom end is a flat bottom; the upper hammer head and the lower hammer rod can be quickly assembled and disassembled by one of the connection methods of bolts, pins, screw threads, and threaded sleeves, or directly welded into one body; the specifications of the lower hammer rod are adapted according to the precast pipe piles or retaining wall steel pipes used in actual construction, and it is required that its diameter is 3-5 cm smaller than the center hole diameter of the precast pipe pile or the inner diameter of the retaining wall steel pipe, and it is required that its length is greater than the length of the precast pipe pile or the retaining wall steel pipe; when the precast pipe pile or the retaining wall steel pipe is relatively long, the lower hammer rod can be quickly connected and disassembled by using a multi-section combination method to increase or decrease its length to meet the construction needs.

2. The special-shaped tamping hammer for pile forming according to claim 1, characterized in that, Guide arms or guide grooves are provided on two sides of the upper hammer head for connecting the vertical support of the construction equipment, and a lifting point is provided at the center position of the top of the upper hammer head for connecting the lifting device of the construction equipment; during construction, the lower hammer rod of the special-shaped rammer passes through the center hole of the precast pipe pile or the inner cavity of the retaining wall steel pipe. After the special-shaped rammer is lifted to a certain height by the pile driver lifting device, the special-shaped rammer makes a free fall along the vertical support of the construction equipment, and the upper hammer head generates the main impact energy above the precast pipe pile or the retaining wall steel pipe, and the bottom end of the lower hammer rod generates an impact force.

3. The special-shaped rammer for pile forming according to claim 1, characterized in that, The shape of the upper hammer head of the special-shaped rammer is cylindrical or square-columnar or multi-sided columnar.

4. The special-shaped rammer for pile forming according to claim 1, characterized in that, One or more diameter-expanded sections are provided at the bottom or the middle part of the lower hammer rod of the special-shaped rammer to prevent the rammer from sucking.

5. The special-shaped rammer for pile forming according to claim 1, characterized in that, When the structure of the lower hammer rod is a single-layer steel pipe or a double-layer steel pipe, one or several materials of lead, steel slag, stone powder, crushed stone, sand, concrete, and mortar are filled into the steel pipe to increase its mass.

6. The special-shaped rammer for pile forming according to claim 1, characterized in that, The lower hammer rod can be quickly connected and disassembled by using a multi-section combination method, and its connection and disassembly method is one of the connection methods of bolts, pins, screw threads, and threaded sleeves.

Images