CN209162913U - A kind of existing building quality inspection of the piles device - Google Patents

Abstract

The utility model discloses an existing building foundation pile quality detection device, comprising a hydrophone, an acceleration sensor, a pulse discharge source equipment and a data analysis system; the pulse discharge source equipment is provided with a pulse discharge electrode, which is located on the top of the foundation pile. An excitation hole and a collection hole are opened on the bearing platform, the bottoms of the excitation hole and the collection hole are both the top of the foundation pile, the excitation hole is filled with clean water, the pulse discharge electrode and the water The hydrophones are placed in the excitation holes, the acceleration sensors are placed at the bottom of the collection holes, and the hydrophones and the acceleration sensors are respectively connected to the data analysis system. By adopting the utility model, the quality of the foundation pile can be accurately judged, and at the same time, the utility model has the advantages of high efficiency and low cost.

Description

An existing building foundation pile quality detection device

technical field

The utility model relates to the field of nondestructive testing of building foundation piles, in particular to a quality testing device for existing building foundation piles.

Background technique

Existing building piles are used as the bearing foundation of buildings, and their quality will directly determine the safety and durability of the superstructure; , ships and bridges impacted by floods, the quality inspection of the foundation piles of their houses and bridges will become very important; in addition, for the phenomenon of inclination, deformation, settlement and cracking of the upper buildings due to foundation problems or construction quality problems, It is necessary to carry out quality inspection on the foundation piles of the corresponding buildings; when repairing, strengthening, increasing the load and transforming the old buildings, the integrity and bearing capacity of the foundation piles of the original buildings must be known in advance, so as to formulate Therefore, it is of great significance to detect the quality of foundation piles of existing buildings through accurate, efficient and low-cost detection methods for understanding the bearing capacity of foundation piles and ensuring the safety of upper buildings.

Different from the newly-built foundation piles with free pile ends, the upper pile ends of the existing building foundation piles are very concealed, the detection environment is complex, and the detection results are hindered and interfered by the bearing platform and the upper building structure. , such as core drilling method, static load test method, traditional high and low strain method, etc. are not applicable, and like the sound wave transmission method, it is obviously not suitable for the detection of foundation piles of existing buildings due to the need to arrange sound pipes in the piles in advance; For the detection of foundation piles, the traditional low-strain reflection method is a relatively reliable method for detecting the integrity of foundation piles. It is difficult to directly contact the pile end with the blocking of the building structure, and the bearing capacity of the foundation pile cannot be known by this method; the traditional hydroelectric effect method places a bucket device at the pile end, and a high-voltage discharge electrode is placed in the bucket device. The high-voltage pulse discharge generates a pressure pulse to excite the top of the foundation pile, and then the dynamic response of the pile-soil system under the action of the pressure pulse is received by the pressure sensor placed in the bucket, and the vibration characteristics of the pile-soil system are analyzed in the time domain and frequency domain respectively. Analysis, infer the nature, size and location of the pile body defect, and calculate the allowable bearing capacity of the foundation pile, but when the hydroelectric effect method is used to detect the foundation pile, the bucket needs to be placed on the top of the foundation pile, which is obviously not suitable for existing building foundations. Pile detection. Patent CN85104819 introduces a method for testing the integrity of foundation piles by using hydroelectric effect. The method adopts the method of placing a bucket on the top of the pile to generate excitation force, and placing a speed sensor on the top of the pile or on the side of the pile, which mainly uses self-power Spectrum to judge the quality of foundation piles, the installation method of acquisition equipment is still not suitable for the detection of foundation piles of existing buildings.

Utility model content

The technical problem to be solved by the present invention is to provide a high-efficiency and low-cost device for detecting the quality of existing building piles, which can accurately judge the quality of foundation piles and calculate the allowable bearing capacity of foundation piles.

In order to solve the above-mentioned technical problems, the utility model provides an existing building pile quality detection device, which includes a hydrophone, an acceleration sensor, a pulse discharge source equipment and a data analysis system; the pulse discharge source equipment is provided with The pulse discharge electrode is provided with an excitation hole and a collection hole on the platform at the top of the foundation pile. The bottoms of the excitation hole and the collection hole are both the top of the foundation pile. The excitation hole is filled with clean water. The pulse discharge electrode and the hydrophone are both placed in the excitation hole, the acceleration sensor is placed at the bottom of the collection hole, and the hydrophone and the acceleration sensor are respectively analyzed with the data. system connection.

As a preferred solution of the present invention, the vibration excitation hole is arranged at the center of the foundation pile.

As a preferred solution of the present invention, the collection hole is arranged at a radius of two thirds from the center of the foundation pile.

As a preferred solution of the present invention, the hydrophone is located at a lower position in the middle of the excitation hole.

As a preferred solution of the present invention, the pressure sensing surface of the hydrophone is parallel to the bottom plane of the excitation hole.

As a preferred solution of the present invention, a layer of quick-hardening mortar is arranged at the bottom of the collecting hole to make the bottom of the collecting hole flat, and an iron plate is arranged on the upper part of the quick-hardening mortar.

As a preferred solution of the present invention, the plane of the iron plate is parallel to the horizontal plane of the end of the foundation pile.

As a preferred solution of the present invention, the acceleration sensor is adsorbed on the iron plate by a magnetic attraction device.

As a preferred solution of the present invention, the existing building pile quality detection device further includes an amplifier, and the hydrophone and the acceleration sensor are respectively connected to the data analysis system through the amplifier.

Compared with the prior art, an existing building foundation pile quality detection device implemented by the utility model has the following beneficial effects:

(1) The present utility model uses the impact of the pulse discharge electrode in the excitation hole of the cap water injection as the excitation force, and the excitation force generated by the discharge of the pulse discharge electrode is directly transmitted by the water medium to the lower pile body of the transmission foundation pile, using The hydrophone and acceleration sensor placed in the excitation hole and the collection hole collect the reflected wave pressure waveform and reflected wave vibration waveform of the foundation pile under the impact of pulse discharge. By analyzing the collected data, the foundation pile can be accurately judged The quality of the pile body can be judged whether there are defects in the pile body, such as: the specific location, type, size, etc. of the defects; in addition, the design of the excitation hole and the collection hole avoids the excessive attenuation of the longitudinal wave energy due to the excessive thickness of the bearing platform. It can be seen that the utility model can accurately judge the quality of the foundation pile, and has the advantages of high efficiency and low cost at the same time.

(2) The utility model can realize non-destructive testing of the quality of existing building foundation piles. Compared with the traditional low-strain reflection method, this method uses the pulse discharge impact in the water injection hole (ie the excitation hole) as the excitation force , which can solve the problem that it is difficult to use heavy hammers to excite vibration in narrow spaces such as house basements, and at the same time avoid the interference of the upper pile cap, raft, shear wall and other buildings on the detection process.

(3) The utility model adopts the water medium to conduct the exciting force, and utilizes the characteristic that the water cannot transmit the shear strain, which can greatly reduce the interference of the shear wave and the surface wave to the detection.

(4) Compared with the traditional hydroelectric effect method, the utility model adopts the reflected wave pressure waveform curve and the reflected wave vibration waveform curve to synchronously analyze the integrity of the foundation pile, which can greatly improve the detection accuracy of the foundation pile.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings of the embodiments will be briefly introduced below.

FIG. 1 is a schematic structural diagram of an existing building foundation pile quality detection device provided by the present invention.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

As shown in FIG. 1 , a preferred embodiment of an existing building pile quality detection device provided by the present invention includes a hydrophone 4, an acceleration sensor 5, a pulse discharge source device 8 and a data analysis system 10; The pulse discharge source equipment 8 is provided with a pulse discharge electrode 3, and an excitation hole 7 and a collection hole 6 are opened on the bearing platform 2 at the top of the foundation pile 1, and the bottom of the excitation hole 7 and the collection hole 6 are both. It is the top of the foundation pile 1, the excitation hole 7 is filled with clean water, the pulse discharge electrode 3 and the hydrophone 4 are placed in the excitation hole 7, and the acceleration sensor 5 is placed in the acquisition The bottom of the hole 6 , the hydrophone 4 and the acceleration sensor 5 are respectively connected to the data analysis system 10 .

Therefore, the present invention uses the pulse discharge impact in the excitation hole 7 of the water-filled cap 2 as the excitation force, and the excitation force generated by the discharge of the pulse discharge electrode 3 is directly transmitted by the water medium to the lower pile body of the transfer foundation pile 1 , using the hydrophone 4 and the acceleration sensor 5 placed in the excitation hole 7 and the collection hole 6 respectively to collect the reflected wave pressure waveform and reflected wave vibration waveform of the foundation pile 1 under the impact of the pulse discharge. The data analysis can accurately judge the quality of the foundation pile 1, and based on the principle of dynamic measurement method, the bearing capacity of the foundation pile 1 can be estimated, and whether the pile body has defects, such as: the specific location, type, size, etc. of the defect; The hole 7 and the collection hole 6 are designed to avoid excessively thick longitudinal wave energy attenuation due to the excessive thickness of the support platform 2 . It can be seen that the utility model can accurately judge the quality of the foundation pile 1 and calculate the allowable bearing capacity of the foundation pile 1, and has the advantages of high efficiency and low cost at the same time.

It should also be noted that the utility model can realize non-destructive testing of the quality of existing building foundation piles. Compared with the traditional low-strain reflection method, the method uses the pulse discharge shock in the water injection hole as the excitation force, which can solve the problem. The problem that it is difficult to use heavy hammers to excite vibration in narrow spaces such as house basements; at the same time, it avoids the interference of buildings such as caps, rafts, and shear walls on the upper part of the foundation piles on the detection process; at the same time, the utility model adopts water medium conduction. Exciting force can greatly reduce the interference of shear waves and surface waves on detection by utilizing the property that water cannot transmit shear strain; in addition, compared with the traditional hydroelectric effect method, the utility model adopts the reflected wave pressure waveform curve and the reflected wave vibration The waveform curve synchronously analyzes the integrity of the foundation pile, which can greatly improve the detection accuracy of the foundation pile.

Exemplarily, in order to ensure the detection effect of the hydroelectric effect method, the excitation hole 7 is located at the center of the foundation pile 1 , and the collection hole 6 is arranged at two-thirds of the radius from the center of the foundation pile 1 . .

Exemplarily, the hydrophone 4 is located at the lower part of the middle of the excitation hole 7, and the pressure sensing surface of the hydrophone 4 is parallel to the bottom plane of the excitation hole 7, so as to ensure the hydrophone. The accuracy of the detection results of the device 4.

Exemplarily, after drilling the collection hole 6, use quick-hardening mortar to level the hole bottom of the collection hole 6, place an iron plate on top of the quick-hardening mortar, and make the plane of the iron plate parallel to the base. On the horizontal plane of the end of the pile 1, the acceleration sensor 5 is firmly adsorbed on the iron plate by the magnetic suction device. Applying a layer of quick-hardening mortar on the installation surface can increase the connection reliability of the uneven installation surface. Fix the acceleration sensor 5 firmly to ensure the accuracy of the detection result of the acceleration sensor 5 .

Exemplarily, the quality detection device for the existing building pile 1 further includes an amplifier 9, and the hydrophone 4 and the acceleration sensor 5 are respectively connected to the data analysis system 10 through the amplifier 9. The amplifier 9 It can amplify the power of the collected signal.

The detection steps of applying the quality detection device for existing building foundation piles provided by the present utility model include the following steps:

(1) According to the positional relationship between the foundation pile 1, the cap 2 and the upper building, determine the arrangement position and drilling depth of the excitation hole for placing the pulse discharge electrode 3 and the collection hole for placing the acceleration sensor, And use the core drilling machine to drill holes, and use the core drilling machine to clean the scum at the bottom of the hole after drilling the hole.

After drilling the collection hole 6, use quick-hardening mortar to level the bottom of the collection hole 6, place an iron plate on top of the quick-hardening mortar, and make the plane of the iron plate parallel to the end of the foundation pile 1. The accelerometer 5 is firmly attached to the iron plate by the magnetic device, and a layer of quick-hardening mortar is applied on the installation surface to increase the connection reliability of the uneven installation surface. The iron plate can attach the acceleration sensor 5 to the iron plate. Fix it firmly to ensure the accuracy of the detection result of the acceleration sensor 5 .

(2) Fill the excitation hole with clean water. After filling with clean water, place the pulse discharge electrode 3 and the hydrophone in the excitation hole 7 , and place the acceleration sensor in the collection hole 6 .

(3) Turn on the power of the pulse discharge source equipment 8 and charge the power supply. After the hydrophone 4, the acceleration sensor 5 and the data analysis system all enter the acquisition state, discharge the pulse discharge electrode 3 of the pulse discharge source equipment 8 operate.

(4) The data analysis system 10 performs time domain and frequency domain analysis on the reflected wave pressure waveform collected by the hydrophone 4 and the reflected wave vibration waveform collected by the acceleration sensor 5 to determine whether the pile body has defects, including the type and location of the defect. , size and other information; Fourier transform is performed on the reflected wave pressure waveform and reflected wave vibration waveform, and the judgment of the integrity of the pile body is further verified through the characteristics of the spectrum curve.

It should also be noted that in the step (4), the calculation step of the static load allowable bearing capacity of the foundation pile is also included: according to the reflected wave pressure waveform curve of the foundation pile collected by the hydrophone 4, the dynamic movement of the foundation pile vibration is calculated. Stiffness, according to the basic principle of dynamic measurement method, to obtain the allowable bearing capacity of foundation pile static load. In addition, according to the size parameters of the foundation pile 1, the adjustment of the excitation force is realized by adjusting the discharge voltage of the pulse discharge source device 8, and the steps (3) and (4) are repeated to improve the detection by comparing multiple sets of data. precision.

What is disclosed above is only the preferred embodiment of the present invention, of course, it cannot limit the scope of rights of the present invention. Therefore, the equivalent changes made according to the scope of the present invention are still covered by the present invention. scope.

Claims (9)

1. a kind of existing building quality inspection of the piles device, which is characterized in that including hydrophone, acceleration transducer, pulse Focus equipment of discharging and data analysis system；The pulsed discharge focus equipment is equipped with pulse discharge electrode, at the top of foundation pile Exciting hole and acquisition hole are offered on cushion cap, the exciting hole and the bottom hole for acquiring hole are the top of foundation pile, exciting hole Clear water is inside filled, the pulse discharge electrode and the hydrophone are both placed in the exciting hole, the acceleration transducer It is placed on the bottom hole in the acquisition hole, the hydrophone and the acceleration transducer connect with the data analysis system respectively It connects.

2. existing building quality inspection of the piles device as described in claim 1, which is characterized in that the exciting hole is arranged in The center of the foundation pile.

3. existing building quality inspection of the piles device as described in claim 1, which is characterized in that the acquisition hole is arranged in 2/3rds radial location of center apart from the foundation pile.

4. existing building quality inspection of the piles device as described in claim 1, which is characterized in that the hydrophone is located at institute State the middle part position on the lower side in exciting hole.

5. existing building quality inspection of the piles device as described in claim 1, which is characterized in that the pressure of the hydrophone Sensitive surface is parallel to the hole baseplane in the exciting hole.

6. existing building quality inspection of the piles device as described in claim 1, which is characterized in that the bottom hole in the acquisition hole Equipped with one layer of fast hard mortar, make the bottom hole leveling for acquiring hole, the top of fast hard mortar is provided with iron plate.

7. existing building quality inspection of the piles device as claimed in claim 6, which is characterized in that the plane of the iron plate is flat Row is in the end horizontal face of the foundation pile.

8. existing building quality inspection of the piles device as claimed in claim 7, which is characterized in that the acceleration transducer It is adsorbed on the iron plate by magnetic attracting device.

9. existing building quality inspection of the piles device as described in claim 1, which is characterized in that it further include amplifier, institute Hydrophone and the acceleration transducer is stated to connect with the data analysis system respectively by the amplifier.