A control method for foundation pit sliding construction

Abstract

This invention relates to a control method for slip-down construction of foundation pits, comprising the following steps: providing multiple lifting devices and steel supports, wherein force sensors and displacement sensors are installed on the lifting devices, and the lifting devices are installed at both ends of the steel supports; comparing the values ​​of the force sensors of the lifting devices at both ends, if the value at one end is greater than the value at the other end, lifting the lifting device at the end with the larger value until the values ​​of the force sensors at both ends are equal, so that the steel support is balanced; lowering the steel support into the foundation pit using the lifting devices, calculating the lowering distance using the displacement sensors, so that the steel support is lowered to a predetermined set height, which is simple to operate and convenient to use.

Description

Technical Field

[0001] This invention relates to the field of foundation pit construction technology, and specifically to a control method for foundation pit sliding construction. Background Technology

[0002] Currently, in the construction of multi-layer steel supports for foundation pits, a sliding construction method can be adopted. This method involves assembling all layers of steel supports before excavation begins and using a lifting device to raise them to a height above the surface of the foundation pit. Once the foundation pit is excavated to the designed height of each layer of support, all steel support components are lowered to the designed height for rapid installation.

[0003] During the lowering process, because multiple lifting devices are usually set up, inconsistent lowering heights of the steel supports can easily occur, leading to problems such as steel support components slipping, uneven stress on the lifting ropes causing eccentric loads, and other safety hazards. Furthermore, controlling the end of the lowering process relies on manual measurement, which, for a continuous dynamic lowering process, is prone to untimely and inaccurate measurements, resulting in lowering failures. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a control method for the sliding construction of foundation pits. The method uses the force sensor and the displacement sensor to detect whether the steel support is in a balanced state and controls the deviation of the lowering height and the lowering distance of the steel support.

[0005] The technical solution to achieve the above objectives is a control method for slip-out construction of foundation pits, which includes the following steps:

[0006] Multiple lifting devices and steel supports are provided. The lifting devices are equipped with force sensors and displacement sensors, and the lifting devices are installed at both ends of the steel supports.

[0007] Compare the force sensor values ​​of the lifting devices at both ends. If the value at one end is greater than the value at the other end, lift the lifting device at the end with the larger value until the force sensor values ​​at both ends are equal, so that the steel support is balanced.

[0008] The steel support is lowered into the pit using the lifting device, and the lowering distance is calculated using the displacement sensor, so that the steel support is lowered to a predetermined height.

[0009] Furthermore, two lifting devices are provided at each of the two opposite ends of the steel support, and the two lifting devices are arranged opposite to each other on both sides of the steel support;

[0010] When balancing the steel support, the values ​​of the two force sensors located at the same end are summed to obtain the tensile sum value. The tensile sum values ​​of the force sensors located at both ends are compared. If the tensile sum value at one end is greater than the tensile sum value at the other end, the two lifting devices at the end with the larger tensile sum value are lifted until the tensile sum values ​​of the force sensors at both ends are equal.

[0011] Furthermore, when balancing the steel support, the values ​​of the force sensors of the two lifting devices at the same end are compared. If the value on one side is greater than the value on the other side, the lifting device on the side with the larger value is lifted until the values ​​of the force sensors on both sides are equal.

[0012] Furthermore, when balancing the steel support, the average value of the values ​​of the two displacement sensors located at the same end is taken to obtain the average displacement value. The average displacement values ​​of the displacement sensors located at both ends are compared. If the average displacement value of one end is greater than the average displacement value of the other end, the two lifting devices at the end with the larger average displacement value are lifted until the average displacement values ​​of the force sensors at both ends are equal.

[0013] Furthermore, when the steel support is lowered into the foundation pit, the values ​​of the displacement sensors of the two lifting devices at the same end are compared. If the value of one side is greater than the value of the other side, the side with the larger value is lifted by the lifting device until the values ​​of the displacement sensors on both sides are equal.

[0014] Furthermore, when the steel support is lowered into the foundation pit, it is determined that H0-h-H1≤S;

[0015] Where H0 is the initial height of the steel support, h is the distance the steel support has descended, H1 is the height of the predetermined setting position of the steel support, and S is the standard control step length of a single lowering of the lifting device.

[0016] If H0-h-H1≤S, then the lowering step distance of the lifting device is adjusted to H0-h-H1.

[0017] Furthermore, when the steel support is lowered into the foundation pit, it is determined that H0-h-H1>S;

[0018] If H0-h-H1>S, then the steel support is lowered by a distance S using the lifting device.

[0019] Furthermore, after balancing the steel support, the value of the force sensor is reset to zero.

[0020] Furthermore, after balancing the steel support, the value of the displacement sensor is reset to zero.

[0021] Furthermore, the lowering height of the steel support is determined according to the on-site construction requirements.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The force sensor and displacement sensor are used to detect whether the steel support is in a balanced state, and the deviation of the lowering height and distance of the steel support are controlled. The system is reusable, effectively reducing economic losses caused by construction safety hazards. Attached Figure Description

[0024] Figure 1 This is a diagram illustrating the effect of using the control method for foundation pit sliding construction according to the present invention.

[0025] Legend: 1. Lifting device; 2. Displacement sensor; 3. Force sensor; 4. Lifting rope; 5. Steel support. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] See Figure 1 A control method for foundation pit sliding construction includes the following steps: providing multiple lifting devices 1 and steel supports 5, wherein force sensors 3 and displacement sensors 2 are installed on the lifting devices 1, and the force sensors 3 and displacement sensors 2 are installed on the lifting ropes 4 of the lifting devices 1. Preferably, laser rangefinders, roller rangefinders, or pull wire displacement sensors 2 can be used to measure the stroke of each individual clamping jack or the lowering length of each lifting rope 4. Encapsulated resistance strain gauge sensors or other types of force sensors 3 can be used to measure the tension of each lifting rope 4; the lifting devices 1 are installed at both ends of the steel supports 5; If the force sensor 3 values ​​at one end of the lifting device 1 are greater than those at the other end, it indicates that the center of gravity of the steel support is shifted towards the end with the larger value. That is, the height of the end with the larger value is lower than the height of the end with the smaller value. The lifting device 1 at the end with the larger value is then raised until the force sensor 3 values ​​at both ends are equal, so that the heights of the two ends of the steel support are aligned, thereby balancing the steel support 5. The steel support 5 is then lowered into the pit using the lifting device 1, and the displacement sensor 2 calculates the lowering distance, so that the steel support 5 is lowered to the predetermined set height.

[0028] Furthermore, two lifting devices 1 are provided at each of the two opposite ends of the steel support 5, and the two lifting devices 1 are arranged opposite each other on both sides of the steel support 5. When balancing the steel support 5, the values ​​of the two force sensors 3 located at the same end are summed to obtain the tensile sum value. The tensile sum values ​​of the force sensors 3 located at both ends are compared. If the tensile sum value at one end is greater than the tensile sum value at the other end, the two lifting devices 1 at the end with the larger tensile sum value are lifted until the tensile sum values ​​of the force sensors 3 at both ends are equal. The lifting devices 1 are used to balance the two ends of the steel support 5, so that the ends of the steel support 5 are in a balanced state to prevent the steel support 5 from tipping over when it is lowered. Preferably, the tensile sum values ​​at both ends are compared. If the tensile sum value at one end exceeds the tensile sum value at the other end by 5%, the group with the larger resultant force is lifted upwards until the difference is less than 5%.

[0029] Furthermore, when balancing the steel support 5, the values ​​of the force sensors 3 of the two lifting devices 1 at the same end are compared. If the value on one side is greater than the value on the other side, the lifting device 1 with the larger value is raised until the values ​​of the force sensors 3 on both sides are equal. Preferably, the tension on both sides of the same end of the steel support 5 is compared. If the tension on one side exceeds the tension on the other side by 2%, the side with the larger force is lifted upwards until the difference is less than 2%.

[0030] Furthermore, when balancing the steel support 5, the average values ​​of the two displacement sensors 2 located at the same end are taken to obtain the average displacement value. The average displacement values ​​of the displacement sensors 2 located at both ends are compared. If the average displacement value at one end is greater than the average displacement value at the other end, the two lifting devices 1 at the end with the larger average displacement value are lifted until the average displacement values ​​of the force sensors 3 at both ends are equal. Preferably, the average displacement value of the two displacement sensors 2 at the same end is taken, and the displacement difference between the average displacement values ​​at both ends is compared. If the average displacement value at one end exceeds the average displacement value at the other end by 2cm, the group with the larger displacement is lifted upwards until the difference is less than 2cm.

[0031] Furthermore, when the value of the displacement sensor at one end is greater than the value of the displacement sensor at the other end, it indicates that the center of gravity of the steel support is shifted towards the end with the larger value. That is, the height of the end with the larger value is lower than the height of the end with the smaller value. The lifting device 1 at the end with the larger value is then lifted until the difference in the values ​​of the force sensors 3 at both ends is less than 2cm, so that the heights of the two ends of the steel support are equal, thereby balancing the steel support 5.

[0032] Furthermore, when the steel support 5 is lowered into the foundation pit, the values ​​of the displacement sensors 2 of the two lifting devices 1 at the same end are compared. If the value of one side is greater than the value of the other side, the side with the larger value is lifted by the lifting device 1 until the values ​​of the displacement sensors 2 on both sides are equal. Preferably, the vertical values ​​of the two displacement sensors 2 located at the same end are compared. If the value of one displacement sensor 2 exceeds the value of the other displacement sensor 2 by 1 cm, the side with the larger force is lifted upwards until the difference is less than 1 cm.

[0033] Furthermore, when the steel support 5 is lowered into the foundation pit, it is determined that H0-h-H1≤S; where H0 is the initial height of the steel support 5, h is the distance the steel support 5 has descended, H1 is the height of the predetermined setting position of the steel support 5, and S is the standard control step length of the lifting device 1 for a single lowering, that is, the distance that the lifting device 1 lowers the steel support 5 in a single operation; if H0-h-H1≤S, then the lowering step distance of the lifting device 1 is adjusted to H0-h-H1.

[0034] Furthermore, when the steel support 5 is lowered into the foundation pit, it is determined that H0-h-H1 > S; if H0-h-H1 > S, the steel support 5 is lowered by a distance S using the lifting device 1.

[0035] In this invention, a preferred embodiment is as follows: after the lifting device 1 lowers the steel support 5 by a single standard control step length, the size between H0-h-H1 and S is determined. If H0-h-H1≤S, the lowering step distance of the lifting device 1 is adjusted to H0-hH; if H0-h-H1>S, the steel support 5 is lowered by the lifting device 1 by a distance S, and the above determination operation continues.

[0036] Furthermore, after balancing the steel support 5, the value of the force sensor 3 is reset to zero.

[0037] Furthermore, after balancing the steel support 5, the value of the displacement sensor 2 is reset to zero.

[0038] Furthermore, the lowering height of the steel support 5 is determined according to the on-site construction requirements.

[0039] The following describes the application process of the control method for foundation pit sliding construction according to the present invention.

[0040] The steel support 5 is lifted from the ground to provide the foundation pit excavation face as the initial state control: at this time, the force sensor 3 is used to control the force balance and attitude of the overall lifting.

[0041] The values ​​of the two force sensors 3 located at the same end are combined to obtain the sum of the tension. The sum of the tension at the two ends is compared. If the difference exceeds 5%, the end with the larger sum of tension is lifted upward until the difference is less than 5%.

[0042] Compare the values ​​of the two force sensors 3 located at the same end. If the difference exceeds 2%, lift the side with the larger value upwards until the difference is less than 2%.

[0043] After achieving force balance, the value of displacement sensor 2 is reset to zero. At the same time, the initial height H0 of the steel support 5 is manually measured.

[0044] The average value of the two displacement sensors 2 located at the same end is taken to obtain the average displacement value. The displacement difference between the average displacement values ​​at the two ends is compared. If the average displacement value at one end exceeds the average displacement value at the other end by 2cm, the group with the larger displacement is lifted upward until the difference is less than 2cm.

[0045] Compare the values ​​of the two displacement sensors 2 located at the same end. If the value of one side exceeds the value of the other side by 1cm, lift the side with the larger value upward until the difference is less than 1cm.

[0046] The above control is the displacement control when each step (the standard control step length for each step is S, which is generally the working stroke of the main top) is completed. After the displacement balance control is completed, the total sliding height at this time is automatically calculated, which is the previous value plus the average of all displacement values ​​at this time.

[0047] The process of decentralization includes the following steps:

[0048] When H0-h-H1≤S

[0049] Adjust the lowering step distance to H0-h-H1, where H1 is the original design bottom elevation of the support. The lowering construction is completed when this step is completed.

[0050] When H0-h-H1>S, continue the standard control step size S release process.

[0051] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. Those skilled in the art can make various modifications to the present invention based on the above description. Therefore, certain details in the embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention shall be defined by the appended claims.

Claims

1. A method for controlling slippage construction in foundation pits, characterized in that, Includes the following steps: Multiple lifting devices and steel supports are provided. The lifting devices are equipped with force sensors and displacement sensors, and the lifting devices are installed at both ends of the steel supports. Compare the force sensor values ​​of the lifting devices at both ends. If the value at one end is greater than the value at the other end, lift the lifting device at the end with the larger value until the force sensor values ​​at both ends are equal, so that the steel support is balanced. The steel support is lowered into the pit using the lifting device, and the lowering distance is calculated using the displacement sensor, so that the steel support is lowered to the predetermined set height. The values ​​of two force sensors located at the same end are summed to obtain the tensile force. The tensile force sums at the two ends are compared. If the difference exceeds 5%, the end with the larger tensile force sum is lifted upwards until the difference is less than 5%. Compare the values ​​of the two force sensors located at the same end. If the difference exceeds 2%, raise the side with the larger value until the difference is less than 2%. After the force balance is completed, the displacement sensor value is reset to zero, and the initial height H0 of the steel support is measured manually at this time. The average value of the two displacement sensors located at the same end is taken to obtain the average displacement value. The displacement difference between the average displacement values ​​at the two ends is compared. If the average displacement value at one end exceeds the average displacement value at the other end by 2cm, the group with the larger displacement is lifted upward until the difference is less than 2cm. The values ​​of two displacement sensors located at the same end are compared. If the value of one side exceeds the value of the other side by 1 cm, the side with the larger value is lifted upwards until the difference is less than 1 cm.

2. The control method for slippage construction of foundation pits according to claim 1, characterized in that: Two lifting devices are provided at each of the two opposite ends of the steel support, and the two lifting devices are arranged opposite to each other on both sides of the steel support; When balancing the steel support, the values ​​of the two force sensors located at the same end are summed to obtain the tensile sum value. The tensile sum values ​​of the force sensors located at both ends are compared. If the tensile sum value at one end is greater than the tensile sum value at the other end, the two lifting devices at the end with the larger tensile sum value are lifted until the tensile sum values ​​of the force sensors at both ends are equal.

3. The control method for slippage construction of foundation pits according to claim 1, characterized in that: in When the steel support is lowered into the foundation pit, it is determined that H0-h-H1≤S; Where H0 is the initial height of the steel support, h is the distance the steel support has descended, H1 is the height of the predetermined setting position of the steel support, and S is the standard control step length of a single lowering of the lifting device. If H0-h-H1≤S, then the lowering step distance of the lifting device is adjusted to H0-h-H1.

4. The control method for slippage construction of foundation pits according to claim 3, characterized in that: in When the steel support is lowered into the foundation pit, it is determined that H0-h-H1>S; If H0-h-H1>S, then the steel support is lowered by a distance S using the lifting device.

5. The control method for slippage construction of foundation pits according to claim 1, characterized in that: After balancing the steel support, the value of the force sensor is reset to zero.

6. The control method for slippage construction of foundation pits according to claim 1, characterized in that: The lowering height of the steel support is determined according to the on-site construction requirements.

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