31results about How to "Reduce negative friction" patented technology

The invention discloses a combined PHC pipe pile capable of reducing a negative friction effect. The combined PHC pipe pile comprises an upper PHC pipe pile section and a lower PHC pipe pile section, wherein a telescopic part is arranged between the two PHC pipe pile sections; the telescopic part comprises a telescopic part top plate, a telescopic part bottom plate and a hydraulic jack positioned between the telescopic part top plate and the telescopic part bottom plate; a hook is welded at the lower bottom surface of the telescopic part top plate; small pulleys are welded at the top surface of the telescopic part bottom plate; the telescopic part is internally provided with a steel strand; one end of the steel strand is tied to the hook at the lower bottom surface of the telescopic top plate, and the other end of the steel strand downwards bypasses two small pulleys on the telescopic part bottom plate, then upwards passes through a small hole of the telescopic part top plate and then is connected with an intra-pile bracket on the top of the PHC pipe pile through the interior of the PHC pipe pile; the top of the PHC pipe pile is provided with a displacement transfer device. According to the combined PHC pipe pile, the hydraulic jack is utilized for actively settling the upper PHC pipe pile section, so that the negative friction resistance of a pile body can be effectively reduced or even eliminated.

The invention discloses an underwater coating construction method for reducing negative friction force of a pile body. The underwater coating construction method comprises the following steps that geofabric pieces are cut out from geofabric, wherein the sizes of the geofabric pieces are matched with the size of the underwater pile body, firstly, the surfaces of the geofabric pieces are coated with cold base oil, after the cold base oil on the surfaces of the geofabric pieces permeates or volatilizes, then a first layer of pitch is laid, then a second layer of pitch is laid, the geofabric pieces dried on the pitch layers cover the surface of the underwater pile body and are reinforced, during construction, the multiple geofabric pieces are constructed from the lower end to the upper end of the underwater pile body in sequence, and the upper and lower adjacent geofabric pieces are in lap joint. The underwater coating construction method for reducing the negative friction force of the pile body is simple in technology, convenient to operate and low in investment, and through field monitoring on an actual project, it shows that the underwater coating construction method for reducing the negative friction force of the pile body is high in maneuverability and obvious in effect.

A pretreatment method for a super-thick waste soil foundation comprises the following steps that 1, the surface of a super-thick waste soil field is leveled and compacted; 2, air permeability preventing composite geotechnical cloth is laid on the surface of the super-thick waste soil field; 3, the super-thick waste soil field where the air permeability preventing composite geotechnical cloth is laid is constructed for hole drilling; 4, a vacuum negative pressure method or a deep degradation method or an incineration method is determined as a treatment method of the super-thick waste soil foundation; and 5, the portions, around drilled holes, of the super-thick waste soil foundation are ram-reamed and compacted, and pile foundation engineering is constructed. According to the pretreatment method, a super-thick waste soil layer is pretreated into a regenerated soil layer, so that the foundation soil strength is improved, the foundation settlement amount is reduced, and negative friction resistance of foundation soil to latterly constructed piles is reduced; and the technical problems that a traditional foundation treatment method is narrow in application range and limited in reinforced depth, and the bearing force of a reinforced foundation cannot meet design requirements are solved.

The invention discloses a method for reinforcing an existing pile foundation in a collapsed loess area by slip casting. The method is a method required for reinforcement of a checking valve pipe of the existing pipe foundation adjacent to an underground project during construction. In the method, checking valve pipe slip casting is adopted as a main reinforcing technical measure; and the method comprises the following steps of: distributing slip casting hole positions on a pile foundation bearing table and at the periphery of the pile foundation bearing table within a certain range; after a driller finishes drilling, installing a checking valve pipe; filling a prepared shell material into an annular space between the checking valve pipe and the wall of the drilled hole; when the shell material reaches certain strength, reinforcing the soil at the periphery of the pile foundation by slip casting; after slip casting, covering a slip casting protective cover; and performing slip casting at any time as required. By the reinforcing method, a pile body negative friction force of the soil body at the periphery of the pile foundation in the collapsed loess area due to collapsibility can be reduced, the bearing capacity of the pile foundation is enhanced, the settlement of the pile foundation due to the underground project construction is decreased, and an aim of reinforcing by slip casting is fulfilled.

The invention discloses a track steel-pipe pile capable of reducing negative friction force and a construction method, and belongs to the technical field of building foundation engineering. The track steel-pipe pile comprises a pile body, gear shafts, T-shaped steel beams and a rigid track. Concrete is poured into a round steel pipe to form the pile body. The middle of each gear shaft is provided with a one-way rotating gear, and the two ends of each gear shaft are provided with one-way rotating pulleys. Webs of the T-shaped steel beams are annularly welded to the outer side of the pile body at equal intervals. The gear shafts are symmetrically welded to the two sides of the webs of the T-shaped steel beams and are arranged at equal intervals in the longitudinal direction of the webs. The rigid track is composed of track shoes and track pins. The two ends of each track shoe are provided with holes, and the track shoes are connected through the corresponding track pins to form the rigid track. The rigid track is engaged with the one-way rotating gears on the gear shafts and further attached to the one-way rotating pulleys at the two ends of the gear shafts, and the rigid track can be closed through the track pins so that the track steel-pipe pile can be formed. According to the track steel-pipe pile capable of reducing negative friction force and the construction method, through one-way rotation of the rigid track, pile-soil positive friction force can be increased while the pile-soil negative friction force is reduced, insufficient bearing capacity of the pile body is prevented, and safety and stability of an upper structure are guaranteed.

The invention relates to a carbon fiber cloth bag cast-in-situ anti-arch curved surface combined irregular-shaped pile, which is characterized in that the upper part of the combined irregular-shaped pile is a round pile body while the lower part thereof is an anti-arch curved surface pile body, and the pile bottom is provided with an irregular-shaped prefabricated pile tip. A carbon fiber cloth bag wraps the outside of the pile body; a steel sleeve with a reinforcing plate is arranged on the top part of the combined irregular-shaped pile; a vertical drain body is filled in the cavity at the outer side of the round pile body; a vertical drain pipe communicated with the vertical drain body is preset in a cast-in-situ cover plate on the top part of the pile. The carbon fiber cloth bag arranged on the outer side of the pile body can reinforce the pile body, improve the stress performance of the pile body and enhance the integrity of the pile body; the section of the pile body on the lower part is an anti-arch curved surface which can prevent influence from excessive fullness of concrete of the pile body to the lateral friction of the pile; the section of the pile body on the upper part is round and can reduce the influence from the lateral negative friction of the pile to the performance of the pile body. The invention also discloses a construction method of the combined irregular-shaped pile.

The invention discloses a prefabricated pile negative friction resistance reduction and positive friction resistance transmission device and use method, comprising: a fixing part 1 sequentially arranged on the outside of the prefabricated pile from top to bottom, a degradable random fiber laminated fiberboard and a fixing part 2. Both the fixed part 1 and the fixed part 2 are provided with a cavity, and the two cavities are connected by a sliding link, and the two ends of the sliding link are provided with a sliding part, and the sliding part is limited up and down in the cavity Sliding; the outside of the degradable random-filament laminated fiberboard is provided with a porous permeable plate, which is used to wrap and fix the degradable random-filament laminated fiberboard on the outside of the prefabricated pile. Advantages: It enriches the existing prefabricated pile foundation construction technology, and develops a device and application technology that can reduce the negative friction resistance of prefabricated piles; through the degradable random fiber laminated fiberboard, the slippage is promoted to further reduce the negative friction resistance, and there is no pollution biodegradable.

The invention relates to a top-reinforced cast-in-place concrete thin-walled pipe pile, which is characterized in that the main body of the thin-walled pipe pile adopts double-layer steel sinking pipes to form a pile, the pile diameter on the upper part of the pile body is enlarged, and The outside of the concrete pile body of the enlarged section is provided with plastic sleeves and vertical drainage bodies in sequence from the inside to the outside; the enlarged section of the pile diameter is connected to the upper prefabricated pile tip, and the bottom of the pile body is connected to the lower prefabricated pile tip; the soil around the pile on the upper part of the thin-walled pipe pile The solidification treatment is to solidify the soil layer; connecting ribs are arranged between the top of the thin-walled pipe pile, the closed section of the pile core and the pile top cover plate; the drainage channel connected with the vertical drainage body is arranged in the pile top cover plate. The invention not only improves the driving quality of the pile body, but also improves the mechanical properties of the upper pile body and the soil around the pile, and at the same time prevents the deformation of the pile body caused by the mud belt coming out of the ground, and has better technical and economic benefits. The invention also discloses a construction method of the thin-walled pipe pile.