CN103363904B - The measurement mechanism of foundation pit enclosure structure layering horizontal shift and measuring method - Google Patents

Abstract

The invention provides a measuring device and a measuring method for layered horizontal displacement of an enclosure structure of a foundation pit. The measuring device includes a relative displacement measuring device and an absolute displacement measuring device. The relative displacement measuring device includes The first alignment device on the side, the first laser distance measuring sensor installed on the first alignment device and the displacement reflective sheet installed on the second enclosure structure. The absolute displacement measuring device includes a second alignment device fixedly installed on the top surface of the first enclosure structure, a second laser ranging sensor installed on the second alignment device and a reference reflective sheet outside the foundation pit. The first and second alignment devices both include a base with a ball socket in which the ball socket is spherically matched with a ball head rotor. The ball head rotor is fixedly connected with the first and second laser distance measuring sensors. The ball socket and the ball head There is a locking device between the rotors. The measuring device has a simple structure, the measuring process is simple and fast, and the measuring method has high measuring precision.

Description

Measuring device and method for layered horizontal displacement of foundation pit enclosure structure

technical field

The invention relates to a device and a method for measuring horizontal displacement at different depths of an enclosure structure of foundation pit engineering. In particular, it relates to a measuring device and method for measuring the horizontal displacement of the foundation pit enclosure structure in layers when both sides of the foundation pit enclosure structure are substantially parallel.

Background technique

During the construction of foundation pit engineering, the horizontal displacement at different depths of the foundation pit enclosure structure is the main evaluation index of the safety of foundation pit engineering, so it is the main monitoring item in the process of foundation pit construction.

The horizontal displacement at different depths of the foundation pit enclosure structure is generally measured with an inclinometer after the inclinometer tube is buried in the enclosure structure. The burial of the inclinometer pipe is complicated, the measurement cost is high, and the measurement result is unstable, so the accuracy is difficult to guarantee. At home and abroad, there are also some studies on measuring the horizontal displacement of the foundation pit enclosure structure at different depths based on the principle of laser ranging. The devices involved in these studies have relatively complex structures or large sizes. During the entire measurement period, the fixing device of the laser distance measuring sensor needs to be installed on each layer of the foundation pit enclosure structure, which is easily affected by blasting vibration and mechanical impact, thereby affecting the measurement accuracy, and may even cause the measurement device to be damaged. smashed. In addition, due to the limitation of the structure of the fixture, some laser ranging sensors have specific requirements for the installation position of the measuring point and the instrument, otherwise the laser transmitter cannot find the target point to be measured. Since each measurement line must be installed with a corresponding laser rangefinder fixture during measurement, the consumption is large and the cost is high, so it has not been widely used in engineering practice.

The existing methods for measuring the layered horizontal displacement of the foundation pit enclosure structure mainly include the axis method, small angle method, and total station coordinate change method. The first two methods use theodolite and steel ruler for measurement, and the total station coordinate change method is adopted The total station measures the included angle and distance at the same time, and uses the conversion formula to calculate the horizontal displacement value of the foundation pit enclosure structure. All the above measurement methods have certain disadvantages. The axis method and the small angle method have higher requirements on the site. The base point of the measurement work should be selected not far from the foundation pit and a point that basically does not move during the excavation of the foundation pit. , if the selected distance of the base point is longer, the accuracy of the steel ruler reading from the theodolite will be lower. Although the total station coordinate change method has high measurement accuracy, its measurement process is cumbersome and the measurement cost is high.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a simple in structure and easy to install measuring device for layered horizontal displacement of foundation pit enclosure structure and a simple and quick measuring process with high accuracy of measuring results. Measurement methods.

In order to achieve the above purpose and other related purposes, the present invention provides a measuring device for layered horizontal displacement of the foundation pit enclosure structure, the foundation pit enclosure structure includes a first enclosure structure and a second enclosure structure located on both sides of the foundation pit Protective structure, the first and second protective structures both include ring beams and protective walls. The measuring device provided by the present invention includes a relative displacement measuring device and an absolute displacement measuring device, and the relative displacement measuring device includes a first alignment device fixedly installed on the side of the first enclosure structure, a first alignment device installed on the first fixed The first laser ranging sensor on the line device and the displacement reflective sheet installed on the second enclosure structure; the absolute displacement measuring device includes a second alignment device fixedly installed on the top surface of the first enclosure structure, an installation The second laser ranging sensor and a reference reflective sheet on the second alignment device, the reference reflective sheet is fixedly arranged at the reference point on one side of the first enclosure structure, and the first and second alignment devices Each includes a base, and a ball socket is arranged in the base, and the ball socket is spherically matched with a ball-end rotor, and the ball-end rotor is fixedly connected with the first and second laser ranging sensors, and the ball socket and the ball There is also a locking device between the head rotors.

Preferably, screws are fixed on the ball rotor, and the first and second laser ranging sensors are connected to the ball rotor through the screws.

Preferably, the locking device is a locking screw installed on the base, the head of the locking screw is exposed from the base, and the tail of the locking screw extends into the ball socket Inside.

Preferably, the first alignment device is fixedly installed on the side of the ring beam of the first enclosure structure through a first expansion screw; the second alignment device is fixedly installed on the first expansion screw through a second expansion screw. A top surface of a ring beam of an envelope structure.

Preferably, both ends of the first and second expansion screws have threads, and the threads have a fixed length.

Preferably, an external trigger line and an external trigger button are connected to the first and second laser distance measuring sensors.

Preferably, the distance from the reference point to the second laser ranging sensor is greater than or equal to 5 times the excavation depth of the foundation pit.

The present invention also provides a method for measuring the layered horizontal displacement of the enclosure structure of the foundation pit, which includes the following steps: selecting a reference point, taking the installation place of the second laser ranging sensor as the reference measuring point, and using the second laser ranging The sensor measures the distance value l from the reference point to the reference measurement point according to the measurement frequency, and according to the measurement frequency, the difference between each measurement value _lj and the initial measurement value _l0 is the absolute horizontal displacement value of the reference measurement point Δl _j , Δl _j =|l _j -l ₀ |, where j represents the number of measurements, j=0,1,2...;

Taking the installation place of the first laser distance measuring sensor as the working base point, along with the excavation of each layer of the foundation pit, install the displacement reflectors sequentially on the corresponding layers of the second enclosure structure, Taking the installation place of the displacement reflective sheet as the displacement measuring point, using the first laser ranging sensor to measure the distance value l _ij from the working base point to each displacement measuring point according to the measurement frequency and the number of excavation layers, Among them, i represents the number of excavation layers; the difference Δl _ij =|l _ij -l _i0 of each measurement value l _ij and the initial measurement value l _i0 | on the horizontal line is the displacement measuring point of the i-th layer to the The relative horizontal displacement value of the working base point δ _ij , δ _ij = Δl _ij sinθ _i , where h _i is the depth of the foundation pit when the i-th layer is excavated;

The difference between the relative horizontal displacement value δ _ij of the displacement measuring point of the i-th layer to the working base point and the absolute horizontal displacement value Δl _j of the reference measuring point is the absolute value of the displacement measuring point of the i-th layer. Horizontal displacement S _ij , S _ij =|δ _ij -Δl _j |.

Preferably, the measurement method also includes a correction method for the relative horizontal displacement value δ _ij from the displacement measuring point on the i-th layer to the working base point: let δ _ij '=δ _ij +δ _i-1,k , Among them, δ _ij ′ is a correction value; i=2,3,...; k is the first measurement of the distance value l _i0 from the displacement measuring point of the i-th layer to the working base point, for the i-1th The number of measurements of the layer; δ _i-1,k is when the distance value l _i0 from the displacement measuring point of the i-th layer to the working base point is measured for the first time, the displacement measuring point of the i-1th layer is relative to the The relative horizontal displacement value of the above working base point.

As mentioned above, the measuring device and measuring method for layered horizontal displacement of foundation pit enclosure structure of the present invention have the following beneficial effects:

1. The laser distance measuring sensor is installed on the measuring point of the foundation pit enclosure structure through a detachable alignment device. The alignment device has a simple structure and is convenient for installation and measurement at any time to avoid damage to the measurement device. Affecting the normal construction of the foundation pit, the measuring device for the layered horizontal displacement of the entire foundation pit enclosure structure is easy to popularize and apply;

2. Carry out layered measurement according to the excavation depth of the foundation pit, and take into account the horizontal displacement value of the previous layer when measuring the horizontal displacement measuring points of this layer, and correct the measurement results to make the measurement results more accurate and reliable;

3. The point contact between the ball socket and the ball head rotor of the alignment device effectively solves the large error and surface contact caused by the surface contact between the measuring instrument and the fixing device and the button after the traditional measuring device is installed. Problems such as poor stability and poor repeatability of the measurement results.

Description of drawings

Fig. 1 shows the schematic diagram of the layered horizontal displacement measuring device of the foundation pit enclosure structure and the principle diagram of the measuring method according to the present invention.

Fig. 2 is a partially enlarged schematic diagram of a measuring device for layered horizontal displacement of foundation pit enclosure structure according to the present invention.

Fig. 3 shows the principle diagram for correcting the relative horizontal displacement values of the displacement measuring points of each layer in the method for measuring the layered horizontal displacement of the foundation pit enclosure structure of the present invention.

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to attached drawings 1 to 3. It should be noted that the diagrams provided in this embodiment are only schematically illustrating the basic idea of the present invention, and only the components related to the present invention are shown in the diagrams rather than the number, shape and shape of the components in actual implementation. Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

Fig. 1 is a schematic diagram of a measuring device provided by the present invention, which is used to measure the layered horizontal displacement of the foundation pit enclosure structure. As shown in Figure 1, the foundation pit enclosure structure 4 includes a first enclosure structure 41 (the enclosure structure on the left side shown in Figure 1) and a second enclosure structure 42 (in Figure 1) on both sides of the foundation pit 1 showing the enclosure structure on the right), the first enclosure structure 41 and the second enclosure structure 42 each include a ring beam 411 and an enclosure wall 412 . The measuring device comprises a relative displacement measuring device 21 and an absolute displacement measuring device 22 .

The relative displacement measuring device 21 includes a first alignment device 211 , a first laser ranging sensor 212 and a plurality of displacement reflectors 213 . The first alignment device 211 is fixedly installed on the side of the first enclosure structure 41, the first laser ranging sensor 212 is installed on the first alignment device 211, and each displacement reflective sheet 213 is installed on the second enclosure structure 42 .

The absolute displacement measuring device 22 includes a second alignment device 221 , a second laser ranging sensor 222 and a reference reflective sheet 223 . The second alignment device 221 is fixedly installed on the top surface of the first enclosure structure 41, the second laser ranging sensor 222 is installed on the second alignment device 221, and the reference reflective sheet 223 is fixedly arranged on the first enclosure structure 41 Datum point 31 on one side. The distance l from the reference point 31 to the second laser ranging sensor 222 is greater than or equal to 5 times the excavation depth h of the foundation pit 1, that is, l≧5h.

Fig. 2 shows the partially enlarged schematic view of the measuring device for the layered horizontal displacement of the foundation pit enclosure structure of the present invention. As shown in Fig. 2, the first alignment device 211 and the second alignment device 221 each include a base 23, A ball socket 231 is arranged in the base 23, and the ball socket 231 forms a spherical fit with a ball-end rotor 232, and the ball-end rotor 232 is fixedly connected with the first laser distance measuring sensor 212 and the second laser distance measuring sensor 222, and the ball socket 231 and the A locking device 24 is provided between the ball rotors 232 . In the embodiment, the locking device 24 is a locking screw 241 installed on the base 23, the head 2411 of the locking screw 241 is exposed on the base 23, and the tail 2412 of the locking screw 241 extends into the ball socket 231 .

A screw 2321 is fixed on the ball rotor 232, and the first laser distance measuring sensor 212 and the second laser distance measuring sensor 222 are provided with a threaded hole 2121 matched with the screw 2321, through the cooperation of the screw 2321 and the threaded hole 2121, the first The laser ranging sensor 212 , the second laser ranging sensor 222 and the ball head rotor 232 are connected together. The first alignment device 211 is fixedly installed on the side of the beam 411 of the first enclosure structure 41 by the first expansion screw 214, and the second alignment device 221 is fixedly installed on the first enclosure structure 41 by the second expansion screw 224. on the top surface of the beam 411. Both the ends of the first expansion screw 214 and the second expansion screw 224 have threads 25, and the length of the threads 25 is fixed, just in time to cooperate with the threaded hole 233 at one end of the base 23, so that the alignment device can be fixedly installed in the same position every time , ensuring high alignment accuracy.

When measuring the layered horizontal displacement of the foundation pit enclosure structure, a fixed reference point 31 is determined outside the foundation pit on the same side of the first enclosure structure 41 as required, and a reference reflective sheet is arranged at this reference point 31 223, install the second alignment device 221 connected with the second laser ranging sensor 222 on the second expansion screw 224, the elevation of the reference reflective sheet 223 is basically the same as the installation elevation of the second alignment device 221, forming an absolute displacement Measuring device 22. The installation place of the second laser ranging sensor 222 is taken as the reference measuring point 32 .

Opposite to the first expansion screw 214, a displacement measuring point 341 is determined on the side of the ring beam 411 of the second enclosure structure 42, and a displacement reflective sheet 213 is installed to connect the first alignment of the first laser ranging sensor 212. The device 211 is installed on the first expansion screw 214 , and the installation place of the first laser ranging sensor 212 is used as the working base point 33 to form the relative displacement measuring device 21 .

The reflective surfaces of the displacement reflective sheet 213 or the reference reflective sheet 223 are as vertical as possible to the laser measuring line emitted by the first laser ranging sensor 212 or the second laser ranging sensor 222 . By rotating the ball head rotor 232, the angle of the laser emission of the first laser distance measuring sensor 212 or the second laser distance measuring sensor 222 can be adjusted arbitrarily, so as to realize the precise alignment of the measuring line between measuring points. After aiming the laser emitting point at the center of the displacement reflective sheet 213 or the reference reflective sheet 223, rotate the head 2411 of the locking screw 241 so that the tail 2412 of the locking screw 241 goes deep into the ball socket 231 to tighten the ball head rotor 232, Thereby, the first laser distance measuring sensor 212 or the second laser distance measuring sensor 222 is locked, and the laser emission angle is fixed. Due to the point contact between the ball socket 231 and the ball rotor 232, problems such as poor stability and poor repeatability of the measurement results caused by the surface contact between the measuring instrument and the fixing device after the traditional laser distance measuring sensor is installed are effectively solved.

Both the first laser distance measuring sensor 212 and the second laser distance measuring sensor 222 are connected with an external trigger line and an external trigger button, which can eliminate the measurement error caused by the direct contact trigger device when the button is pressed. When the laser spot hits the center of the reference reflective sheet 223 or the displacement reflective sheet 213, press the external trigger button to record the reading. The first laser distance measuring sensor 212 and the second laser distance measuring sensor 222 have a number storage function and a clock timing function for the measurement results, and there is enough memory. The data interface can import data into a computer, and the data resolution is 0.1mm.

The invention also provides a measurement method for measuring the layered horizontal displacement of the foundation pit enclosure structure by using the above measurement device. Figure 1 shows a schematic of the measurement method.

Use the second laser ranging sensor 222 to measure the distance value l _j from the reference measuring point 32 to the reference point 31 according to the measurement frequency, and according to the measurement frequency, the difference between each measurement value l _j and the initial measurement value l ₀ is the reference measurement point The absolute horizontal displacement value Δl _j of 32, Δl _j = |l _j -l ₀ |, where j represents the number of measurements, j=0, 1, 2.... In an embodiment, the measurement frequency is once a day.

With the excavation of each layer of the foundation pit 1, the displacement reflective sheet 213 is sequentially installed on the corresponding layers of the second enclosure structure 42, and the installation position of the displacement reflective sheet 213 is used as the displacement measuring point 34, and the first laser distance measurement is used. The sensor 212 respectively measures the distance l _ij from the working base point 33 to each displacement measuring point 34 according to the measurement frequency and the number of excavation layers, where i represents the number of excavation layers. The difference between the measured value l _ij obtained each time and the initial measured value l _i0 Δl _ij = |l _ij -l _i0 | The projection on the horizontal line is the relative distance between the displacement measuring point 34 and the working base point 33 when excavating to the i-th layer Horizontal displacement value δ _ij .

When excavating the first layer 11 of the foundation pit 1, the displacement measuring point 341 is arranged inside the ring beam 411 of the second enclosure structure 42, opposite to the first expansion screw 214 on the side of the ring beam 411 of the first enclosure structure 41, and adjusted The spherical rotor 232 connected to the first laser ranging sensor 212 makes the laser emitting point collide with the displacement reflector 213 to measure the distance from the displacement measuring point 341 to the working base point 33 . The ring beam can be regarded as a rigid body without deformation, so each measurement value is a constant value l ₁ .

When excavating to the second layer 12, the third layer 13..., displacement reflectors 213 are arranged at corresponding positions inside the enclosure wall 412 of the second enclosure structure 42 to form displacement measuring points 342, 343.... As shown in Figure 1, h _i is the depth of foundation pit 1 when the i-th layer is excavated. Since the θ _i of the i-th layer changes very little each time it is measured, it can be considered that δ _ij =Δl _ij sinθ _i .

Both the reference measuring point 32 and the working base point 33 are set on the ring beam of the first enclosure structure 41, and the ring beam is a rigid body, so the reference measuring point 32 and the working base point 33 have the same absolute horizontal displacement value Δl _j .

The difference between the relative horizontal displacement value δ _ij of each displacement measuring point 34 to the working base point 33 and the absolute horizontal displacement value Δl _j of the reference measuring point 32 is the absolute horizontal displacement S _ij of the displacement measuring point 34 of the i-th layer, S _ij = |δ _ij -Δl _j |.

For example, when excavating to the third layer 13, the relative horizontal displacement value δ _3j =Δl _3j sinθ ₃ of the displacement measurement point 343 of the third layer 13 to the working base point 33 measured each time, Δl _3j = |l _3j -l ₃₀ |. The absolute horizontal displacement S _3j =|δ _3j -Δl _j | of the displacement measuring point 343 of the third layer 13 .

The first laser distance measuring sensor 212 and the second laser distance measuring sensor 222 are the same laser distance measuring sensor, so in the embodiment, the first laser distance measuring sensor 212 and the second laser distance measuring sensor 222 can be interchanged. After the second laser distance measuring sensor 222 has measured the distance value _lj from the reference measuring point 32 to the reference point 31, the second laser distance measuring sensor 222 is removed from the second alignment device 221, and then installed on the first alignment The device 211 is used to measure the distance l _ij from the working base point 33 to each displacement measuring point 34 . Measurements can also be completed using only one laser distance sensor throughout the measurement process.

As shown in Fig. 1 and Fig. 3, above are the relative horizontal displacements and the absolute horizontal displacements measured after the displacement reflectors 213 of each displacement measuring point 34 are laid out. 34 Before the foundation pit enclosure structure 4 is laid, a certain horizontal displacement has occurred, so the measured relative horizontal displacement value can be corrected from the excavation of the second layer 12 by the following method:

Make δ _ij ′=δ _ij +δ _i-1,k , wherein, i=2,3,...; when k is the distance value l _i0 from the displacement measuring point 34 of the i-th layer to the working base point 33 for the first time, the The number of measurements of the i-1th layer; δ _ij ′ is the correction value; δ _{i-1, k} is the distance value l _i0 from the displacement measuring point 34 of the i-th layer to the working base point 33 when the first measurement is made, the i-1th layer The relative horizontal displacement value of the displacement measuring point 34 relative to the working base point 33.

For example, when excavating to the third floor 13, when the displacement measuring point 343 of the third floor 13 is laid on the maintenance wall, the enclosure wall 412 has undergone a horizontal displacement, and when the displacement measuring point 343 of the third floor 13 is measured for the first time to the working base point When the distance value l of 33 is ₃₀ , the displacement measurement point 342 of the second layer 12 is measured 5 times, and the horizontal displacement value δ ₂₅ of the displacement measurement point 342 of the second layer 12 relative to the working base point 33 is obtained, so the correction value δ _3j '=δ _3j +δ ₂₅ .

To sum up, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (9)

1. the measurement mechanism of a foundation pit enclosure structure layering horizontal shift, described foundation pit enclosure structure (4) comprises the first building enclosure (41) and the second building enclosure (42) that are positioned at foundation ditch (1) both sides, described first, second building enclosure (41, 42) collar tie beam (411) and enclosure wall (412) is included, it is characterized in that: described measurement mechanism comprises a relative displacement measurement mechanism (21) and an absolute displacement measuring apparatus (22), described relative displacement measurement mechanism (21) comprises the first alignment device (211) be fixedly mounted on the first building enclosure (41) side, the displacement reflecting piece (213) being arranged on the first laser range sensor (212) on described first alignment device (211) and being arranged in the second building enclosure (42), described absolute displacement measuring apparatus (22) comprises the second alignment device (221) be fixedly mounted on the first building enclosure (41) end face, be arranged on the second laser range sensor (222) on the second alignment device (221) and a benchmark reflecting piece (223), benchmark reflecting piece (223) is fixedly installed on reference point (31) place of described first building enclosure (41) side, described first, second alignment device (211, 221) pedestal (23) is included, a ball-and-socket (231) is provided with in pedestal (23), ball-and-socket (231) and bulb rotor (232) mating spherical surfaces, bulb rotor (232) and described first, second laser range sensor (212, 222) be fixedly connected with, locking device (24) is also provided with between described ball-and-socket (231) and described bulb rotor (232).

2. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 1, it is characterized in that: bulb rotor (232) is fixed with screw (2321), be connected by described screw (2321) between first, second laser range sensor described (212,222) with described bulb rotor (232).

3. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 1, it is characterized in that: described locking device (24) is for being installed in the lock-screw (241) on described pedestal (23), the head (2411) of described lock-screw (241) exposes to described pedestal (23), and the afterbody (2412) of described lock-screw stretches in described ball-and-socket (231).

4. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 1, is characterized in that: described first alignment device (211) is fixedly mounted on the side of the collar tie beam (411) of described first building enclosure (41) by the first setscrew (214); Described second alignment device (221) is fixedly mounted on by the second setscrew (224) on the end face of the collar tie beam (411) of described first building enclosure (41).

5. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 4, it is characterized in that: the end of first, second setscrew described (214,224) all has screw thread (25), and described screw thread (25) has regular length.

6. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 1, is characterized in that: (212,222) are all connected with external triggering line and external trigger button to first, second laser range sensor described.

7. the measurement mechanism of foundation pit enclosure structure layering horizontal shift according to claim 1, is characterized in that: described reference point (31) is more than or equal to 5 times of described foundation ditch (1) cutting depth to the distance of described second laser range sensor (222).

8. adopt the measurement mechanism described in claim 1 to carry out a method for foundation pit enclosure structure layering horizontal shift measurement, it is characterized in that comprising the following steps:

Selected reference point (31), using described second laser range sensor (222) installation place as benchmark measuring point (32), the distance value l of described reference point (31) to described benchmark measuring point (32) is measured according to survey frequency with the second laser range sensor (222), according to survey frequency, each measured value l _jwith first measured value l ₀difference be the abswolute level shift value Δ l of described benchmark measuring point (32) _j, Δ l _j=| l _j-l ₀|, wherein j represents pendulous frequency, j=0,1,2

Using the installation place of described first laser range sensor (212) as working base point (33), along with the excavation of described foundation ditch (1) each layer, the corresponding each layer of described second building enclosure (42) installs described displacement reflecting piece (213) successively, using described displacement reflecting piece (213) installation place as displacement measuring points (34), measure the distance value l of described working base point (33) to each described displacement measuring points (34) with described first laser range sensor (212) according to described survey frequency and the excavation number of plies _ij, wherein i represents the excavation number of plies; Each measured value l _ijwith first measured value l _i0difference DELTA l _ij=| l _ij-l _i0| the described displacement measuring points (34) being projected as i-th layer is on a horizontal to the relative horizontal displacement value δ of described working base point (33) _ij, δ _ij=Δ l _ijsin θ _i, wherein h _ifor excavation is to the degree of depth of foundation ditch when i-th layer; During ground floor (11) of excavation pit (1), displacement measuring points (341) is arranged on inside the collar tie beam of the second building enclosure (42), relative with first setscrew (214) of the first building enclosure (41) collar tie beam side, adjust the bulb rotor (232) be connected on the first laser range sensor (212), make laser emission point sight displacement reflecting piece (213), record the distance value of displacement measuring points (341) to working base point (33); Collar tie beam is the rigid body do not deformed, and therefore each measured value is a definite value l ₁;

The displacement measuring points (34) of described i-th layer is to the relative horizontal displacement value δ of described working base point (33) _ijwith the abswolute level shift value Δ l of described benchmark measuring point (32) _jdifference be the abswolute level displacement S of the displacement measuring points (34) of described i-th layer _ij, S _ij=| δ _ij-Δ l _j|.

9. the method measured of foundation pit enclosure structure layering horizontal shift according to claim 8, is characterized in that, also comprises the described displacement measuring points (34) of the described i-th layer relative horizontal displacement value δ to described working base point (33) _ijmodification method:

Make δ _ij'=δ _ij+ δ _{i-1, k}, wherein, δ _ij' be modified value; I=2,3, K is the distance value l of described displacement measuring points (34) to described working base point (33) of first described i-th layer of measurement _i0time, to the pendulous frequency of the i-th-1 layer; δ _{i-1, k}for at the distance value l of the first described displacement measuring points (34) measuring i-th layer to described working base point (33) _i0time, the described displacement measuring points (34) of the i-th-1 layer is relative to the relative horizontal displacement value of described working base point (33).