JP3015289B2 - Automatic penetration tester and penetration test method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic penetration tester and a penetration test method for penetrating a penetration rod into the ground, and judging the formation of the formation of the land based on various data in the penetration process.

[0002]

2. Description of the Related Art Conventionally, in order to investigate the bearing capacity of land,
Penetration tests to determine the geological structure of the land based on data such as the number of rotations of the penetration rod at each predetermined depth, the load, etc., are performed in general by widely applying a load and rotation to the penetration rod and penetrating into the ground. I have. At the time of this penetration test, a penetration tester that automatically changes the load applied to the penetration rod, imparts rotation, and the like is used. The penetration tester can load a weight of a predetermined weight and can move up and down along a column, a chuck rotatably disposed on the loading table and capable of holding a penetration rod, and rotationally drives the chuck. Generally, a rotary drive source is provided.In the penetration test, the load on the penetration rod is changed by increasing or decreasing the weight loaded on the loading platform, and a predetermined load is applied to the penetration rod. In this state, the penetrating rod is rotated by driving the rotary drive source to penetrate the ground. At this time, every time the penetrating rod penetrates 250 mm, the load applied to the penetrating rod during that time, observation items such as the sound at the time of penetrating the penetrating rod, and if the penetrating rod is rotating, penetrate 250 mm. The test data such as the number of half rotations required for the test (a value integrated each time the penetrating rod makes a half rotation) is collectively collected by the test staff.

[0003]

In the automatic penetration tester described above, test data collected every time the penetration rod penetrates 250 mm is, for example, 200 mm during the penetration with a load of 490 N {50 kgf} and the remaining 50 mm. 24 penetration
When the test is performed with a load of 5 N {25 kgf}, the load in the test data is 490 N in view of the overall ratio.
It is extremely natural that the data is unifiedly recorded at {50 kgf}. Therefore, speaking of the above example, although there are actually two types of strata between 250 mm,
This will be judged as the same stratum,
Problems such as the inability to know minute changes in soil properties based on test data have occurred. Also, every time the 250 mm penetrates, the test data must be compiled by the test staff during that time, so the experience of the test staff is a very important factor in performing the penetration test. In addition to problems such as the fact that the test data is different, even if you have a lot of experience, it is natural that the test data differs depending on the test staff, and there is also a problem that you cannot know the exact soil quality. .

[0004]

According to the present invention, a loading table is provided with a toothed rotating member rotatable along a meshing member of a column, and a detecting means for detecting the number of rotations of the toothed rotating member is provided. The penetration speed of the penetration rod is calculated based on the detection value of the detection means, the penetration speed is compared with a reference penetration speed set in advance according to the penetration state, and the load and the rotation drive source are determined according to the result. A control device is provided to change the penetration conditions of the drive and record test data such as the load at that time and the half-revolution every time the penetration conditions of the penetration rod change. It is possible to record, and it is possible to eliminate a problem that test data differs depending on test personnel.

[0005] Further, according to the present invention, the lowering force of the loading platform, which is lowered only by its own weight, along the column, is adjusted by the braking force of the brake means, so that it can be lowered integrally with the loading platform and can be rotated by driving a rotary drive source. Change the load on the penetrating rod,
While applying a load to the penetrating rod and rotating the penetrating rod by driving the rotary drive source as needed to penetrate the ground, when the penetrating state of the penetrating rod changes, or the braking force of the brake means is changed. It is also a penetration test method that records test data when the load on the penetration rod changes or when the penetration speed of the penetration rod changes, and this method also records the test data in detail according to the change in the penetration situation. Is possible, and
By recording the test data according to the change in the penetration state by the control device, it is possible to solve the problem that the test data differs depending on the test staff.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic penetration tester and a penetration test method according to the present invention will be described below with reference to the drawings. 1 to 3, reference numeral 1 denotes an automatic penetration tester, which has a loading table 3 on which a weight 11 having a predetermined weight can be loaded and which can be moved up and down along a column 2. The loading platform 3 has a sprocket 3a, which is an example of a toothed rotary member that rotates along a guide chain 2a, which is an example of a meshing member that is vertically arranged along the column 2, and the sprocket 3a is a guide chain. It is configured to move up and down by rotating along 2a. At a position close to the teeth of the sprocket 3a, there is provided a sensor 3b for detecting the passage of the teeth of the sprocket 3a as a pulse signal.
The pulse signal detected by b is sent to the control device 10 where it is converted into a descending amount of the loading platform 3.

A powder brake 6 is connected to the drive shaft 3c of the sprocket 3a. The lowering speed of the loading table 3 is changed by the braking force of the powder brake 6, and a load applied to the penetrating rod 7 described later. It has been changed. The loads applied to the penetrating rod in the penetration test are set to 245N, 490N, 735N, and 980N. In order to obtain these loads, the powder brake 6 is controlled in advance by a control device 10 described below corresponding to each load. The set command value is output. Further, a chuck 8 for detachably holding the penetrating rod 7 is rotatably attached to the loading table 3 by driving of a rotation drive source 9, and is connected to a control device 10 described later in proximity to the chuck 8. Detection means (not shown) is also provided.

The drive shaft 3c of the sprocket 3a
Is connected via a one-way clutch 5 to a rotary drive source 4 such as a motor, which can be rotated forward and backward. When the rotary drive source 4 is driven to rotate forward, the drive is transmitted to the sprocket 3a and the loading table 3 is raised. It is configured to be. Therefore, when the rotation drive source 4 is driven in the reverse direction, the one-way clutch 5 idles, so that the loading platform 3 is not driven until the rotation speed of the drive shaft 3c of the sprocket 3a reaches the rotation speed of the one-way clutch 5. Is lowered by its own weight without being affected by the reduction ratio of the rotary drive source 4. In the actual penetration test, when the penetration rod 7 penetrates into the ground, the rotation speed of the idle one-way clutch 5 is higher than the rotation speed of the drive shaft 3c of the sprocket 3a. Applies only the weight of the loading table 3 as a load.

Reference numeral 10 denotes a control device for controlling the driving of the automatic penetration tester.
, Ie, the amount of penetration of the penetrating rod 7, and the penetrating speed of the penetrating rod 7 is calculated from the amount of penetration and the time measured by a timer or the like. And the half rotation (1/2 rotation) of the chuck 8 is counted and the half rotation number of the penetrating rod 7 is counted.

Further, when the penetrating rod 7 is in a penetrating state of only a load (hereinafter referred to as a self-sinking state), the control device 10 sets the penetrating speed of the penetrating rod 7 to a preset lower limit value Vs of the penetration velocity. It is configured to compare with the penetration speed upper limit value Vc and to drive the rotary drive source, change the load, and the like according to the result, while the penetration rod 7 is rotating and penetrating (hereinafter, referred to as “penetration rod”). , The rotation penetration state), the penetration speed is compared with a preset rotation penetration speed upper limit value Vr, and a stop command of the rotary drive source 9 is output according to the result. Have been. Further, the control device 10 is also set with a boundary value that divides an allowable range from the upper limit value Vc of the penetration speed to the lower limit value Vs of the penetration speed into two regions called Yuckli and Jinwari.

In the control device 10, when the rotary drive source 9 is driven, when the rotary drive source 9 is stopped, when the load is changed, when the penetration speed fluctuates within an allowable range, when the rotary When the platform 3 reaches the bottom dead center, test data such as a load applied to the penetrating rod 7 at that time, a half rotation of the penetrating rod 7, and a sound of the penetrating rod 7 when the penetrating rod 7 is transmitted are recorded. In addition, as the half number of revolutions in the test data, an integrated value while the penetration rod 7 penetrates 250 mm in the rotation penetration state is recorded.

Next, the operation of the automatic penetration tester 1 will be described. The above automatic penetration tester penetrates into the ground by applying penetration conditions such as load and rotational force to a penetration rod held by a chuck. In the present automatic penetration tester 1, the one-way clutch 5 is idled with respect to the drive shaft 3c of the sprocket 3a by the rotation drive source 4 being driven in reverse rotation, whereby the penetration rod 7 held on the chuck 8 is first loaded. The weight of the platform 3 is applied as a load to penetrate the ground.
At this time, the braking force of the powder brake 6 changes according to a command value from the control device 10, whereby the lowering of the loading platform 3 is braked and the load applied to the penetrating rod 7 is changed. The load applied to the penetrating rod 7 is from 245 N {25 kgf} to 245 N {25 kg each time the penetration speed is reduced.
When the penetration speed is reduced at a maximum of 980 N {100 kgf} in 980 N {100 kgf}, and the penetration speed becomes slow at 980 N {100 kgf}, the rotary drive source is driven under the load and the penetration rod 7 is rotated to rotate the ground. Penetrate inside. In addition,
In the present automatic penetration test machine 1, since the weight of the loading platform 3 is applied as a load to the penetration rod 7, the equipment weight of the loading platform 3 is set to at least 980 N {100 kgf}.

In the case where the penetration speed increases during rotation penetration, that is, when the penetration rod 7 penetrates into the ground with only the load regardless of rotation, the rotary drive door 9 is stopped and the load is temporarily reduced. The load is reduced to 490 N {50 kgf}, and if necessary, further reduced to 245 N {25 kgf}, and thereafter, the load is increased again in units of 245 N as described above, and rotation penetration is performed as necessary.

The processing of the operation of the automatic penetration testing machine 1 as described above is all performed by the control device 10 based on a penetration test processing loop (hereinafter referred to as a processing loop) shown in FIG. In the processing loop, first, after confirming the input state of the stop switch pressed when the penetration test is interrupted, the penetration speed V is measured. When the penetration speed V is measured, the penetration state is confirmed. If the state is a self-sinking state, the process proceeds to a self-sinking loop W, and if the state is a rotationally penetrating state, the process proceeds to a rotary penetration loop R. Here, the confirmation of the penetration state is performed by determining whether or not a drive command of the rotary drive source 9 has been output.

In the self-sinking loop W, a process corresponding to the penetration speed V in the self-sinking state is performed. That is, when the penetration rod 7 is in the self-sinking state, the penetration speed is compared with the penetration speed upper limit value Vc and the penetration speed lower limit value Vs. At that time, when the penetration speed V is larger than the penetration speed upper limit value Vc (V> Vc), the command value of the powder brake 6 is increased, the lowering of the loading platform 3 is braked, and the load applied to the penetration rod 7 is reduced. After the reduction, the load applied to the penetration rod 7 at that time, the sound transmitted through the penetration rod 7 and the like are recorded as test data. When the penetration speed is smaller than the penetration speed lower limit value Vs (V <Vs), the command value of the powder brake 6 is reduced to ease the braking of the loading platform 3 and the load applied to the tip of the penetration rod 7 is increased. After that, record the test data. Further, when the penetration speed V is in the allowable range (Vs <V
<Vc), the penetration speed V is based on the boundary value,
It is determined which area of the gimbal belongs to, and if the area to which the penetration speed belongs at that time differs from the area in the previous processing loop, test data is recorded. When the penetration speed V is smaller than the penetration speed lower limit value Vs, 980N に 100 kg has already been applied to the penetration rod 7.
When a load of f｝ is applied, a drive command for the rotary drive source 9 is issued instead of increasing the load,
Is driven, and the penetrating state of the penetrating rod 7 is switched to the rotational penetrating state.

On the other hand, in the rotation penetration loop R, processing is performed according to the penetration speed V at the time of rotation penetration. That is, when the penetration speed V is equal to or higher than the rotational penetration speed upper limit value Vr (V> V
In r), the rotation drive source 9 is stopped, the penetration state is switched to the self-sinking state, and the test data at that time is recorded.

After the processing according to the self-sinking state and the rotationally penetrating state is performed for the penetration speed V as described above, it is confirmed according to the processing loop whether the loading platform 3 has reached the bottom dead center. . At this time, when the loading platform 3 has reached the bottom dead center, the test data at that time is first recorded, and then the automatic penetration testing machine 1 is temporarily stopped to wait for the work for adding the penetration rod 7. State. Conversely, if the loading platform 3 has not reached the bottom dead center, it is checked whether the penetration amount has reached the 250 mm break, and if it has reached, the penetration state at that time is further confirmed. A confirmation is made. This penetration state is confirmed by looking at the drive command of the rotary drive source 9 as described above. At this time, if the penetrating state is the rotational penetrating state, test data such as the load and the half-rotational number are recorded. If the penetrating state is the self-sinking state, the 250 mm break is ignored and the input state of the above-mentioned stop switch is confirmed. And the above processing is repeated. When the stop switch is input, the operation of the automatic penetration tester 1 is temporarily stopped, and the input of the continuation switch or the end switch provided in the control device 10 is waited. , A process of ending the penetration test.

In the above description, the penetration speed V
As an example of recording the test data every time is changed, the case where the penetration speed V is within a predetermined reference range (Vs <V <Vr), and there is a change between the areas called Yuckli and Jinwari at this time. However, the present invention is not limited to this. For example, when the penetration speed V calculated in the processing loop at a certain time is different from the penetration speed V calculated in the immediately preceding processing loop, the test data The same effect can be obtained even if recording is performed.

[0019]

According to the present invention, there is provided a sensor for detecting the number of rotations of the sprocket which rotates integrally with the lowering of the loading platform, the penetration speed of the penetration rod is calculated based on the detected value of this sensor, and the calculated penetration is calculated. The speed is compared with the upper limit value of the penetration speed, the lower limit value of the penetration speed, and the upper limit value of the rotational penetration speed according to the penetration state of the penetration rod, and based on these results, the penetration conditions such as the load applied to the penetration rod and the drive of the rotary drive source are determined. When the penetration conditions are changed as described above, the penetration test is performed automatically and the penetration test method is to record test data such as load, half-turn, observation items, etc. at that time. It is possible to record test data when penetration conditions are changed due to changes in the stratum, etc., so that the soil properties based on the test data can be known in detail. Moni, problems such as test data is different by the test person in charge can also be eliminated, there is an effect such as can be carried out anyone penetration test, regardless of the experience.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an automatic penetration tester according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of the automatic penetration tester according to the present invention.

FIG. 3 is an enlarged sectional view of a main part of the automatic penetration tester according to the present invention.

FIG. 4 is a flowchart showing an operation process of the automatic penetration tester according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic penetration testing machine 2 Prop 2a Guide chain 3 Loading table 3a Sprocket 3b Sensor 3c Drive shaft 4 Rotation drive source 5 One-way clutch 6 Powder brake 7 Penetration rod 8 Chuck 9 Rotation drive source 10 Control device 11 Weight

Continuation of the front page (56) References JP-A-6-336719 (JP, A) JP-A-6-272235 (JP, A) JP-A-4-323411 (JP, A) JP-A-8-74240 (JP) JP-A-8-270365 (JP, A) JP-A-8-284143 (JP, A) JP-A-8-284144 (JP, A) JP-A-9-95931 (JP, A) Patent 2751030 ( JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) E02D 1/02 G01N 3/40

Claims (5)

(57) [Claims] 1. A loading platform on which a weight having a predetermined weight can be loaded is provided so as to be able to move up and down along a column, a rotating member with teeth is rotatably provided on the loading platform, and a meshing member is arranged along the column. The loading platform moves up and down by rotating the toothed rotating member along the meshing member, and furthermore, the penetration rod can be held by the loading platform, and the penetration rod is integrally rotated by driving a rotary drive source. Along with disposing the chuck, a brake means for braking the rotation of the toothed rotating member is provided, and the load applied to the penetrating rod is changed to a predetermined load by braking the lowering of the loading table by the braking force of the brake means, If necessary, a rotation by the rotation drive source is given to rotate the penetration rod to penetrate the ground, and various test data is obtained during the penetration rod, while the number of rotations of the toothed rotation member is detected. Automatic penetration test characterized by providing a detection device for calculating the penetration speed of the penetration rod based on the detection value of the detection device and recording test data every time the penetration speed changes. Machine. The control device calculates the penetration speed of the penetrating rod based on the detection value of the detecting means, compares the penetration speed with a preset reference penetration speed, and, based on the result, determines whether the penetration speed of the penetrating rod is high. The automatic penetration testing machine according to claim 1, wherein the penetration data is changed and the test data at that time is recorded each time the penetration condition of the penetration rod is changed. 3. A loading platform that descends only by its own weight along a column is braked by a brake means, and a load applied to a penetrating rod that can be lowered integrally with the loading platform and that can be rotated by driving a rotary drive source is changed. While applying a load to the rod and rotating the penetrating rod by driving the rotary drive source as necessary, penetrating into the ground and obtaining various test data during that time, the test at each time when the penetration state of the penetrating rod changes, A penetration test method characterized by recording data. 4. The penetration test method according to claim 3, wherein the test data is automatically recorded by the control device every time the penetration state of the penetration rod changes. The test data is obtained when the penetration state of the penetration rod changes, when the load applied to the penetration rod changes due to the change of the braking force of the brake means, or when the penetration speed of the penetration rod changes. The penetration test method according to claim 3 or 4, wherein the method is recorded.