Intelligent dynamic adjusting type foundation pit supporting system

Abstract

The invention discloses an intelligent dynamic adjusting type foundation pit supporting system, which belongs to the technical field of foundation pit supporting and comprises a supporting pile fixedly mounted on the inner wall of a foundation pit, a main longitudinal beam fixedly mounted at the top of the supporting pile, a plurality of I-shaped steel fixedly connected to the top end of the main longitudinal beam side by side, and a cover plate fixedly connected to the top ends of the I-shaped steel and capable of covering the foundation pit. Longitudinal hydraulic dampers used for adjusting the internal stress of the main longitudinal beams are fixedly connected between the supporting piles on the opposite side walls of the foundation pit, first strain sensors are fixedly installed at the positions, connected with the I-shaped steel, of the main longitudinal beams, and the first strain sensors are electrically connected with edge controllers arranged outside the foundation pit. The edge controller controls the longitudinal hydraulic damper to adjust the internal stress of the main longitudinal beam according to the numerical value of the first strain sensor. By monitoring strain data of the main longitudinal beam in real time and combining feedback control of the edge controller, the longitudinal hydraulic damper dynamically adjusts supporting force, and deformation or damage of a supporting structure caused by local stress concentration is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of foundation pit support, and in particular relates to an intelligent dynamically adjustable foundation pit support system. Background Art

[0002] During foundation pit excavation and pipeline installation construction, temporary passage devices need to be set up to ensure normal and safe passage needs.

[0003] In the prior art, a Chinese patent with publication number CN207846428U discloses a temporary passage device for narrow tunnel construction. However, the passage device cannot dynamically adjust the stiffness and is prone to excessive stress due to vehicle overload.

[0004] Therefore, it is necessary to propose an intelligent dynamic adjustment type foundation pit support system to solve the above problems. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an intelligent dynamically adjustable foundation pit support system to solve the problem in the prior art that the passage device cannot dynamically adjust the stiffness and is prone to excessive stress due to vehicle overload.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: The present invention provides an intelligent dynamically adjustable foundation pit support system, comprising support piles fixedly mounted on the inner wall of the foundation pit, a main longitudinal beam fixedly mounted on the top of the support piles, a plurality of I-beams fixedly connected side by side to the top of the main longitudinal beam, a cover plate capable of covering the foundation pit fixedly connected to the top of the I-beam, a longitudinal hydraulic damper for adjusting the internal stress of the main longitudinal beam fixedly connected between the support piles on opposite side walls of the foundation pit, a first strain sensor fixedly mounted at the connection between the main longitudinal beam and each I-beam, the first strain sensor electrically connected to an edge controller arranged outside the foundation pit, and the edge controller controls the longitudinal hydraulic damper according to the numerical value of the first strain sensor to adjust the internal stress of the main longitudinal beam.

[0007] Furthermore, the method for adjusting the internal stress of the main longitudinal beam by the longitudinal hydraulic damper includes the following steps: S1: When the cover plate is subjected to load, the first strain sensor collects strain data of each connection point of the main longitudinal beam at a fixed frequency and transmits the strain data to the edge controller; S2: When the strain data exceeds the preset activation threshold of the edge controller, the edge controller calculates the adjustment amount of the hydraulic damper based on the deviation between the real-time strain value and the target value. The edge controller then outputs a PWM signal to drive the servo valve of the first hydraulic damper to adjust its expansion and contraction amount or damping force. S3: After the adjustment is completed, the first strain sensor re-collects strain data to form a closed-loop feedback until the data at each measuring point is stable within a safe range.

[0008] Furthermore, the calculation formula of the adjustment amount of the hydraulic damper is: Where, is the strain deviation, 、 、 are the proportional, integral, and differential coefficients respectively.

[0009] Furthermore, a plurality of the transverse supports are arranged side by side in the longitudinal direction, wherein a longitudinal hydraulic damper for adjusting the main longitudinal beam is fixedly installed between the transverse support located at the top and the main longitudinal beam, a bracket for supporting the transverse support is fixedly installed on the side wall of the support pile, and a gap is provided between both ends of the transverse support and the support pile, a transverse hydraulic damper is fixedly installed in the gap, and both ends of the transverse hydraulic damper are fixedly connected to the support pile and the transverse support respectively, the transverse hydraulic damper is electrically connected to the edge controller, a second strain sensor electrically connected to the edge controller is installed in the support pile, and the second strain sensor is used to monitor the strain value at the axis of the support pile.

[0010] Furthermore, the method for adjusting the internal stress of the support pile by the lateral hydraulic damper includes: the edge controller verifies the stability coefficient of the support pile according to the strain value at the axis of the support pile section monitored by the second strain sensor, and when the stability coefficient When it is less than 1, it means that the support pile is in a stable state. The edge controller controls the lateral hydraulic damper to adjust the internal stress of the support pile and monitors the stability coefficient in real time. .

[0011] Furthermore, the stability factor The verification formula is: Where, is the pressure value at the axis of the supporting pile section, is the cross-sectional area of the supporting pile, is the cross-sectional strength of the supporting pile, is the stability coefficient of the supporting pile axis, is the eccentric bending moment of the supporting pile; is the Euler force calculated based on the maximum slenderness ratio of the supporting pile; is the equivalent bending moment coefficient; is the cross-sectional plastic development coefficient of the supporting pile, is the net section modulus.

[0012] Furthermore, the second strain sensor is externally connected to an alarm device. When the strain value detected by the second strain sensor makes the stability coefficient of the support pile At 1 o'clock, the alarm will send out an alarm signal.

[0013] Furthermore, the support pile is provided with a mounting groove, in which an auxiliary support is installed. The auxiliary support is an I-beam, and the two ends of the auxiliary support are respectively fixed to the bottom wall of the mounting groove and the bottom wall of the main longitudinal beam. The second strain sensor is fixedly installed at the connection between the auxiliary support and the mounting groove.

[0014] The beneficial effects of the present invention are: The present invention monitors the strain data of the main longitudinal beam in real time through the first strain sensor, and combines it with the feedback control of the edge controller to enable the longitudinal hydraulic damper to dynamically adjust the supporting force, evenly distribute the load, and reduce deformation or damage of the support structure caused by local stress concentration; it avoids the risk of local failure of traditional support structures due to stress concentration, and significantly improves the safety and adaptability of foundation pit support; the edge controller replaces manual intervention to achieve autonomous response of the support system, especially under complex geological conditions or sudden loads (such as earthquakes and heavy rains), and can quickly adjust the support status to improve construction safety.

[0015] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to make the purpose, technical solutions and beneficial effects of the present invention more clear, the present invention provides the following drawings for illustration: Figure 1 Schematic diagram of the structure of the foundation pit support system according to an embodiment of the present invention.

[0017] The markings in the accompanying drawings are as follows: support pile 1, installation groove 101, main longitudinal beam 2, I-beam 3, cover plate 4, transverse support 5, longitudinal hydraulic damper 6, bracket 7, gap 8, transverse hydraulic damper 9, auxiliary support 10. DETAILED DESCRIPTION

[0018] like Figure 1As shown, the present invention provides an intelligent dynamically adjustable foundation pit support system, comprising: a support pile 1 fixedly installed on the inner wall of the foundation pit, a main longitudinal beam 2 fixedly installed on the top of the support pile 1, a plurality of I-beams 3 fixedly connected to the top of the main longitudinal beam 2 in parallel, a cover plate 4 capable of covering the foundation pit fixedly connected to the top of the I-beam 3, a transverse support 5 fixedly connected between the support piles 1 on opposite side walls of the foundation pit, the transverse support 5 being located below the main longitudinal beam 2, a longitudinal hydraulic damper 6 for adjusting the internal stress of the main longitudinal beam 2 fixedly installed between the transverse support 5 and the main longitudinal beam 2, a first strain sensor fixedly installed at the connection between the main longitudinal beam 2 and each I-beam 3, the first strain sensor being electrically connected to an edge controller arranged outside the foundation pit, the edge controller controlling the longitudinal hydraulic damper 6 according to the numerical value of the first strain sensor to adjust the internal stress of the main longitudinal beam 2.

[0019] In this solution, the cover plate 4 is a composite steel plate with a 20mm thick "steel plate-recycled concrete" sandwich structure, welded to the I-beam 3. When the cover plate 4 is subjected to a load, the first strain sensor collects strain data at each connection point of the main longitudinal beam at a fixed frequency and transmits the data signal to the edge controller. When the strain data exceeds the preset start threshold, the edge controller calculates the adjustment amount of the hydraulic damper based on the deviation between the real-time strain value and the target value. The edge controller outputs a PWM signal to drive the servo valve of the first hydraulic damper 6 to adjust its expansion and contraction or damping force. After the adjustment is completed, the first strain sensor re-collects strain data to form a closed-loop feedback loop until the data at each measuring point stabilizes within a safe range. The calculation formula for the adjustment amount is: Where, is the strain deviation, 、 、 are the proportional, integral, and differential coefficients respectively.

[0020] This solution uses a first strain sensor to monitor the strain data of the main longitudinal beam in real time. Combined with the feedback control of the edge controller, the longitudinal hydraulic damper 6 dynamically adjusts the support force, evenly distributes the load, and reduces deformation or damage to the support structure caused by local stress concentration. It avoids the risk of local failure of traditional support structures due to stress concentration and significantly improves the safety and adaptability of foundation pit support. The edge controller replaces manual intervention to achieve autonomous response of the support system, especially under complex geological conditions or sudden loads (such as earthquakes and heavy rains), and can quickly adjust the support status to improve construction safety.

[0021] In one embodiment of the present invention, a plurality of transverse supports 5 are arranged side by side in the longitudinal direction, wherein a longitudinal hydraulic damper 6 for adjusting the main longitudinal beam 2 is fixedly installed between the transverse support 5 located at the top and the main longitudinal beam 2, and a bracket 7 for supporting the transverse support 5 is fixedly installed on the side wall of the support pile 1. A gap 8 is provided between both ends of the transverse support 5 and the support pile 1, and a transverse hydraulic damper 9 is fixedly installed in the gap 8. The two ends of the transverse hydraulic damper 9 are respectively fixedly connected to the support pile 1 and the transverse support 5, and the transverse hydraulic damper 9 is electrically connected to the edge controller. A second strain sensor electrically connected to the edge controller is installed in the support pile 1, and the second strain sensor is used to monitor the strain value at the axial center of the cross section of the support pile 1.

[0022] In this solution, the edge controller verifies the stability coefficient of the support pile 1 based on the strain value at the cross-section axis of the support pile 1 monitored by the second strain sensor. When it is less than 1, it indicates that the support pile 1 is in a stable state. The edge controller controls the lateral hydraulic damper 9 to adjust the internal stress of the support pile 1 and monitors the stability coefficient in real time. ; Among them, the stability coefficient The verification formula is: Where, is the pressure value at the axis of the support pile 1 section, is the cross-sectional area of the supporting pile 1, is the cross-sectional strength of the supporting pile 1, is the stability coefficient of the axis of supporting pile 1, is the eccentric bending moment value of supporting pile 1; is the Euler force calculated based on the maximum slenderness ratio of support pile 1; is the equivalent bending moment coefficient; is the cross-section plastic development coefficient of supporting pile 1, is the net section modulus.

[0023] In one embodiment of the present invention, the second strain sensor is externally connected to an alarm. When the strain value detected by the second strain sensor causes the stability coefficient of the support pile 1 to At 1 o'clock, the alarm will send out an alarm signal.

[0024] In one embodiment of the present invention, the support pile 1 is provided with a mounting groove 101, and an auxiliary support 10 is installed in the mounting groove 101. The auxiliary support 10 is an I20a I-beam, and the two ends of the auxiliary support 10 are respectively fixed to the bottom wall of the mounting groove 101 and the bottom wall of the main longitudinal beam 2. The second strain sensor is fixedly installed at the connection between the auxiliary support 10 and the mounting groove 101.

[0025] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. An intelligent dynamically adjustable foundation pit support system, comprising support piles fixedly mounted on the inner wall of a foundation pit, characterized in that: A main longitudinal beam is fixedly installed on the top of the support pile, and a plurality of I-beams are fixedly connected to the top of the main longitudinal beam in side by side. A cover plate capable of covering the foundation pit is fixedly connected to the top of the I-beam. A longitudinal hydraulic damper for adjusting the internal stress of the main longitudinal beam is fixedly connected between the support piles on the opposite side walls of the foundation pit. A first strain sensor is fixedly installed at the connection between the main longitudinal beam and each I-beam, and the first strain sensor is electrically connected to an edge controller arranged outside the foundation pit. The edge controller controls the longitudinal hydraulic damper according to the numerical value of the first strain sensor to adjust the internal stress of the main longitudinal beam.

2. The intelligent dynamically adjustable foundation pit support system according to claim 1 is characterized in that: The method for adjusting the internal stress of the main longitudinal beam by a longitudinal hydraulic damper comprises the following steps: S1: When the cover plate is subjected to load, the first strain sensor collects strain data of each connection point of the main longitudinal beam at a fixed frequency and transmits the strain data to the edge controller; S2: When the strain data exceeds the preset activation threshold of the edge controller, the edge controller calculates the adjustment amount of the hydraulic damper based on the deviation between the real-time strain value and the target value. The edge controller then outputs a PWM signal to drive the servo valve of the first hydraulic damper to adjust its expansion and contraction amount or damping force. S3: After the adjustment is completed, the first strain sensor re-collects strain data to form a closed-loop feedback until the data at each measuring point is stable within a safe range.

3. The intelligent dynamically adjustable foundation pit support system according to claim 2 is characterized in that: The calculation formula for the adjustment amount of the hydraulic damper is: Where, is the strain deviation, 、 、 are the proportional, integral, and differential coefficients respectively.

4. The intelligent dynamically adjustable foundation pit support system according to claim 3 is characterized in that: There are multiple transverse supports arranged side by side in the longitudinal direction, wherein a longitudinal hydraulic damper for adjusting the main longitudinal beam is fixedly installed between the transverse support located at the top and the main longitudinal beam, a bracket for supporting the transverse support is fixedly installed on the side wall of the support pile, and a gap is provided between both ends of the transverse support and the support pile, and a transverse hydraulic damper is fixedly installed in the gap, and both ends of the transverse hydraulic damper are fixedly connected to the support pile and the transverse support respectively, the transverse hydraulic damper is electrically connected to the edge controller, and a second strain sensor electrically connected to the edge controller is installed in the support pile, and the second strain sensor is used to monitor the strain value at the axis of the support pile.

5. The intelligent dynamically adjustable foundation pit support system according to claim 4 is characterized in that: The method for adjusting the internal stress of the supporting pile by the lateral hydraulic damper includes: the edge controller verifies the stability coefficient of the supporting pile according to the strain value at the axis of the supporting pile section monitored by the second strain sensor, and when the stability coefficient When it is less than 1, it means that the support pile is in a stable state. The edge controller controls the lateral hydraulic damper to adjust the internal stress of the support pile and monitors the stability coefficient in real time. .

6. The intelligent dynamically adjustable foundation pit support system according to claim 5, characterized in that: Stability factor The verification formula is: Where, is the pressure value at the axis of the supporting pile section, is the cross-sectional area of the supporting pile, is the cross-sectional strength of the supporting pile, is the stability coefficient of the supporting pile axis, is the eccentric bending moment of the supporting pile; is the Euler force calculated based on the maximum slenderness ratio of the supporting pile; is the equivalent bending moment coefficient; is the cross-sectional plastic development coefficient of the supporting pile, is the net section modulus.

7. The intelligent dynamically adjustable foundation pit support system according to claim 6, characterized in that: The second strain sensor is connected to an alarm. When the strain value detected by the second strain sensor makes the stability coefficient of the support pile At 1 o'clock, the alarm will send out an alarm signal.

8. The intelligent dynamically adjustable foundation pit support system according to claim 7, characterized in that: The support pile is provided with a mounting groove, in which an auxiliary support is installed. The auxiliary support is an I-beam, and the two ends of the auxiliary support are respectively fixed to the bottom wall of the mounting groove and the bottom wall of the main longitudinal beam. The second strain sensor is fixedly installed at the connection between the auxiliary support and the mounting groove.

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