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CN-121992826-A - New and old pile foundation load self-adaptive regulation and control device based on pre-compression spring and hydraulic compensation

CN121992826ACN 121992826 ACN121992826 ACN 121992826ACN-121992826-A

Abstract

The invention relates to the technical field of pile foundation construction, and particularly discloses a new and old pile foundation load self-adaptive regulation and control device based on a pre-compression spring and hydraulic compensation, which comprises a pre-compression spring unit arranged between the pile top of a new pile and a bearing platform, wherein the pre-compression spring unit is used for storing and releasing elastic potential energy so as to guide the new pile to sink and provide initial supporting force; the hydraulic buffer damping unit is connected with the pre-pressing spring unit in series, is internally provided with viscous fluid and a fluid channel capable of controlling on-off, and is used for adjusting the sinking rate of the new pile and limiting the damping force to be increased suddenly when the rate is suddenly changed, the hydraulic load compensation unit is arranged in the pile body of the new pile and is used for applying active compensation supporting force to the pile body of the new pile to dynamically compensate the loss of bearing force, and the elastic supporting unit is arranged between the bearing platform and the pile top of the old pile. Through the structure, the device realizes the guiding of the new pile sedimentation process and the buffering of the stress of the old pile, thereby being capable of self-adaptively balancing and stabilizing the vertical load distribution in a common stress system of the new pile foundation and the old pile foundation.

Inventors

  • WU JUNTAO
  • Yi Enze
  • ZHAO LINGSEN
  • WANG KUIHUA
  • ZHAO WEIKAI
  • FU PENGCHENG
  • ZHANG SHURUI
  • LIU SIQI

Assignees

  • 浙江大学

Dates

Publication Date
20260508
Application Date
20260312

Claims (10)

  1. 1. New old pile foundation load self-adaptation regulation and control device based on pre-compaction spring and hydraulic compensation, characterized in that includes: The pre-pressing spring unit (1) is arranged between the pile top of the new pile (14) and the bearing platform (17) and is used for storing and releasing elastic potential energy so as to guide the new pile (14) to sink and provide initial supporting force for the bearing platform (17); The hydraulic buffer damping unit (6) is arranged in series with the pre-pressing spring unit (1) and is used for adjusting the sinking rate of the new pile (14), and a viscous fluid (13) and a fluid channel which can be controlled to be opened and closed are arranged in the hydraulic buffer damping unit so as to limit the damping force from increasing suddenly when the sinking rate changes suddenly; the hydraulic load compensation unit (7) is arranged in the pile body of the new pile (14) and is used for applying active compensation supporting force to the pile body of the new pile (14) so as to dynamically compensate the loss of bearing capacity caused by the settlement of the new pile (14); and the elastic supporting unit (16) is arranged between the bearing platform (17) and the pile top of the old pile (15) and is used for providing flexible support for the old pile (15) and buffering load change.
  2. 2. The self-adaptive regulating device for new and old pile foundation loads based on pre-compression springs and hydraulic compensation according to claim 1, wherein the pre-compression spring unit (1) comprises an elastic element and an adjusting mechanism for adjusting initial compression amount of the elastic element, the lower end of the elastic element is connected with a fixed plate (9) through a stand column (8), and the upper end of the elastic element is connected with a bearing platform (17).
  3. 3. The device for adaptively adjusting and controlling the load of new and old pile foundations based on pre-compression springs and hydraulic compensation according to claim 2, wherein the elastic element is a high-strength spiral spring or a disc spring group.
  4. 4. The new and old pile foundation load self-adaptive regulation and control device based on the pre-compression spring and the hydraulic compensation according to claim 2 is characterized in that the hydraulic buffer damping unit (6) comprises a cylinder body (5), a piston (3) and viscous fluid (13) filled in the cylinder body (5), the piston (3) divides the interior of the cylinder body (5) into an upper cavity and a lower cavity, a main damping channel (4) and an auxiliary bypass channel (12) are arranged on the cylinder body (5) or the piston (3), and the on-off of the auxiliary bypass channel (12) is controlled by a valve control switch (11).
  5. 5. The new and old pile foundation load self-adaptive regulation and control device based on pre-compression springs and hydraulic compensation according to claim 4, characterized in that the opening and closing of the valve control switch (11) is under the combined action of the pre-compression force of the structure limiting spring (10) and the fluid pressure, when the fluid pressure is lower than the pre-compression force, the valve control switch (11) is closed, viscous fluid (13) flows only through the main damping channel (4), and when the fluid pressure is higher than the pre-compression force, the valve control switch (11) is opened, and the auxiliary bypass channel (12) is activated.
  6. 6. The new and old pile foundation load self-adaptive regulation and control device based on pre-compression springs and hydraulic compensation according to claim 4, wherein the fixed plate (9) is provided with an outflow hole (2) for accommodating viscous fluid (13) flowing out due to the movement of the piston (3).
  7. 7. The new and old pile foundation load self-adaptive regulation and control device based on pre-compression springs and hydraulic compensation according to claim 1, wherein the hydraulic load compensation unit (7) comprises an upper loading section and a lower loading section which are arranged oppositely, the upper loading section and the lower loading section respectively push the pile body upper structure and the pile body lower structure upwards and downwards under hydraulic driving, and the hydraulic load compensation unit (7) is connected with an external hydraulic pump station and a control system through a hydraulic pipeline.
  8. 8. The new and old pile foundation load self-adaptive regulation and control device based on pre-compression springs and hydraulic compensation according to claim 7, wherein the control system instructs the hydraulic load compensation unit (7) to act according to new pile (14) settlement and/or pre-compression spring unit (1) supporting force attenuation signals fed back by a monitoring system.
  9. 9. The new and old pile foundation load self-adaptive regulating device based on pre-compression springs and hydraulic compensation according to claim 1, wherein the elastic supporting unit (16) is composed of rubber pads or low-stiffness springs.
  10. 10. The new and old pile foundation load self-adaptive regulation and control device based on pre-compression springs and hydraulic compensation according to claim 1, wherein the hydraulic load compensation unit (7) can be used as a self-balancing loading system for carrying out vertical static load test on a new pile (14) after construction of the new pile (14) and before installation of a bearing platform (17).

Description

New and old pile foundation load self-adaptive regulation and control device based on pre-compression spring and hydraulic compensation Technical Field The invention relates to the technical field of pile foundation construction, in particular to a new and old pile foundation load self-adaptive regulation and control device based on a pre-compression spring and hydraulic compensation. Background In the existing building reinforcement, extension or adjacent new construction, new piles are often added beside the original foundation system, so that the new piles and the existing old piles bear upper load together. The new pile foundation and old pile foundation combined stress system is widely applied in engineering practice, and aims to reduce the stress of old piles and improve the overall safety by sharing the load through new piles. However, after the construction of the new pile is completed, the soil around the new pile is still in a consolidation development stage, so that the new pile tends to generate obvious settlement at the early stage of service, while the old pile is basically stable in settlement and limited in continuous deformation capability due to long-term service. At this time, if the initial settlement of the new pile develops faster or the settlement amount is larger, the relative displacement between the new pile and the upper structure increases rapidly, so that the new pile fails to exert the bearing function in time, and the upper load is intensively transferred to the old pile through the bearing platform or the distributing member, so that the old pile bears additional load beyond the design state, and even causes overload risk, additional settlement and structural potential safety hazard. In view of the above problems, there have been attempts in the prior art to provide a load adjuster between the pile top and the pile cap, such as "a pile soil load adjuster for composite pile foundation" disclosed in chinese patent publication No. CN 110777858B. The adjuster provides a controllable and stable deformation curve when being pressed through presetting the deformation angle of the corner plate, and is used for adjusting the load sharing proportion between piles and soil, thereby improving the calculation accuracy of the composite pile foundation design. However, such a regulator is essentially a passive device based on a fixed deformation characteristic, and the deformation behavior of the device is preset at the time of installation, and cannot be dynamically adjusted according to the settlement development of the pile foundation in the actual service process. In actual engineering, foundation conditions are complex and changeable, and the sedimentation process of a new pile has obvious uncertainty. If the regulator only depends on a preset deformation curve, the regulator is difficult to continuously and effectively adapt to the real-time change of the settlement of the new pile in the whole structure service process, and particularly, the regulator cannot provide timely load compensation when the settlement of the new pile is too fast or suddenly changes. In addition, if rigid connection is adopted between the new pile and the bearing platform, the initial settlement of the new pile can be quickly converted into additional load for the old pile, and if flexible connection is adopted, the long-term bearing capacity of the new pile can not be fully exerted. Therefore, how to realize real-time monitoring, dynamic compensation and self-adaptive balance of load in the new pile settlement development process, and give consideration to the initial settlement control and the later bearing stability of the new pile, is still a key technical problem faced by a new and old pile foundation common stress system. Disclosure of Invention The invention aims to provide a new and old pile foundation load self-adaptive regulation and control device based on a pre-compression spring and hydraulic compensation, which is used for solving the technical problems existing in the prior art. The invention provides a new pile foundation load self-adaptive regulating and controlling device based on a pre-compression spring and hydraulic compensation, which comprises a pre-compression spring unit, a hydraulic buffer damping unit, a hydraulic load compensating unit and an elastic supporting unit, wherein the pre-compression spring unit is arranged between a pile top of a new pile and a pile cap and used for storing and releasing elastic potential energy so as to guide the new pile to sink and provide initial supporting force for the pile cap, the hydraulic buffer damping unit is arranged in series with the pre-compression spring unit and used for regulating the sinking rate of the new pile, viscous fluid and a fluid channel which can be controlled to be opened and closed are arranged in the hydraulic buffer damping unit so as to limit the damping force to be increased suddenly when the sinking rate is suddenly