JP4886921B2 - Effective diameter confirmation method of ground improvement body - Google Patents

Description

  The present invention relates to a method for confirming the effective diameter of a ground improvement body, and more specifically, by a high-pressure jet stirring method, a hardening material liquid is jetted from a jet nozzle of an injection rod that has penetrated to a predetermined depth in the ground, and stirred and mixed. It is related with the method of confirming the effective diameter of the ground improvement body created by doing.

  A high-pressure jet agitation method is known as a method of improving the ground by consolidating the soft ground by injecting a hardening material liquid into the soft ground, increasing the shear strength. The high-pressure jet agitation method is a method in which after the ground is drilled to a predetermined depth using an injection rod, the injection rod mounted on the lower end of the injection rod is pulled up while rotating or swinging the injection rod, A method of forming a cylindrical or fan-shaped ground improvement body by stirring and mixing the hardened material liquid and the soft soil forming the ground while cutting the existing ground by injecting the liquid in the horizontal direction with ultra high pressure. It is.

  In the ground improvement by the high-pressure jet agitation method, it is very important to accurately check the effective diameter in addition to ensuring the strength of the ground improvement body. In other words, if an effective diameter is overestimated when an overlapping part (lap part) between adjacent ground improvement bodies is required, an area that is not ground improved is actually left in the middle part of the adjacent ground improvement body. Will end up. On the contrary, if the effective diameter is estimated too small, the lap portion becomes too wide, resulting in an increase in cost and a decrease in work efficiency.

  Conventionally, the effective diameter of the ground improvement body by the high-pressure jet stirring method has been confirmed by performing check boring after a predetermined curing period has elapsed after construction and the ground improvement body has solidified. That is, at several points in the area estimated to be near the periphery of the ground improvement body, drilling is performed to the depth of the depth section where the ground improvement body exists, and the ground condition is determined based on the solidification of the boring core that hits the outer edge of the ground improvement body. The outer edge of the improved body is determined, and the effective diameter of the ground improved body is estimated. In general, in the post-survey of ground improvement bodies, continuity is confirmed with a specimen sampled by core boring one to two weeks after construction, and strength is confirmed after 28 days.

However, the following problems have been pointed out in the conventional effective diameter measuring method for ground improvement bodies.
(1) Until a plurality of boring cores corresponding to the outer edge of the ground improvement body are obtained, it is sometimes necessary to perform boring a large number of times, and as the number of times increases, much labor and work time are required.
(2) It cannot be confirmed about all the ground improvement bodies formed from the point of work time and cost.
(3) Since the boring is performed after the ground improvement body is consolidated, it is very difficult to accurately form the boring hole in the vertical direction, and the hole is easily bent. Therefore, when measuring the effective diameter at a deep position from the ground surface, the measurement accuracy of the effective diameter decreases.
(4) Since the improved diameter is confirmed after the ground improvement body is consolidated, if it is found that an unmodified part remains between the adjacent ground improvement bodies, additional construction or another type of auxiliary construction method should be performed. Will be necessary and will cause serious difficulties in construction.

  Therefore, a method that can confirm the effective diameter with high accuracy in a short time immediately after the ground improvement work by the high-pressure jet stirring method is eagerly desired.

For example, Patent Document 1 utilizes the fact that the specific resistance value of soil, which is a conductor, differs depending on the type of soil, and the specific resistance of an uncured improved column is based on the voltage or current between electrodes in a plurality of sets of electrodes. A method for estimating the filling and building range of the improved column immediately after the construction at the construction site is disclosed. Patent Document 2 discloses a method for estimating the diameter of a ground improvement body formed by a high-pressure jet stirring method using the relationship that the diameter of the ground improvement body is smaller as the calcium oxide content of the ground improvement body is larger. Is disclosed.
Japanese Unexamined Patent Publication No. 7-18660 JP 2007-182695 A

  However, the method of Patent Document 1 estimates the filling and building range of the improved column by comparing the specific resistance value of the original ground and the specific resistance value of the improved column. The specific resistance value must be measured using the surface electrical inspection method, and there is a problem that time and labor are required for the preparation work.

  The method of patent document 2 estimates the calcium oxide content rate of the soil extract | collected from the ground improvement body, and estimates the diameter of a ground improvement body based on the calibration curve created using the soil extract | collected before improvement. Therefore, after the construction of the high-pressure jet stirring method, work such as soil collection and calcium carbonate measurement is performed, so that a certain amount of time is required. Also, it takes time and labor to collect the soil before improvement and create a calibration curve in advance. Further, this method merely estimates the diameter of the ground improvement body based on a calibration curve created using the soil before improvement, and does not actually confirm the diameter of the ground improvement body.

  The present invention has been made in view of the above problems, and an object thereof is to provide a method for easily and accurately confirming the effective diameter of a ground improvement body formed by a high-pressure jet stirring method immediately after construction. Yes.

  In order to solve the above problems, the effective diameter confirmation method of the ground improvement body of the present invention is agitated by injecting a hardening material liquid from an injection nozzle of an injection rod penetrated to a predetermined depth in the ground by a high-pressure injection stirring method. A method for confirming the effective diameter of a ground improvement body formed by mixing, and capable of photographing the inside of the ground at a predetermined distance from the penetration position of the injection rod before the hardening liquid is cured. A rod-with-camera process for penetrating a camera-equipped rod into the ground, an image display process for displaying an image photographed by the camera on a ground monitor, and the presence of a hardening material liquid for an image photographed at a predetermined depth And an image confirmation step for confirming the image.

  Conventionally, the effective diameter of the ground improvement body has been confirmed by drilling after the ground improvement body is consolidated, but the depth that can be dug in one day is limited, to the deepest part of the ground improvement body Sometimes it took several days to dig. According to the present invention, since the rod with camera is inserted into the soft muddy ground improvement body before the hardening material liquid is hardened, the deepest part of the ground improvement body can be easily reached in a short time without requiring a large force. A rod with a camera can be inserted. Also, the penetrating rod with camera can be pulled up easily and in a short time, so if you move to another position and penetrate the rod with camera, the effective diameter can be confirmed at multiple locations in a short time. It is possible to improve the accuracy of the effective diameter confirmation.

  Further, in the method of boring after the conventional ground improvement body is consolidated, hole bending tends to occur. According to the present invention, the rod with camera is inserted into the soft muddy ground improvement body before the hardening material liquid is hardened. Therefore, the rod with camera can be penetrated to the deep part while maintaining the verticality, and the accuracy of the effective diameter confirmation can be improved.

  Further, according to the present invention, the camera-equipped rod includes a camera capable of photographing the ground, and the photographed image can be displayed in real time on the ground monitor. By confirming the presence of, it is possible to reliably confirm the effective diameter of the ground improvement body. Since the effective diameter of the obtained ground improvement body is not estimated, the quality of the ground improvement body is very reliable. Even if the effective diameter cannot be confirmed at the designed position, it will be known immediately after construction, so it is possible to take measures such as re-construction immediately. The situation where the auxiliary construction method is performed does not occur.

  In order to solve the above-mentioned problem, the effective diameter confirmation method for a ground improvement body according to the present invention is characterized in that, in the image confirmation step, the presence of a hardening material liquid is confirmed for each of images taken at a plurality of points having different depths. It is said.

  Conventionally, the continuity of the ground improvement body has been confirmed using a specimen sampled by core boring one to two weeks after construction, but it is equivalent to the ground improvement body after consolidation as described above. In addition, there is a problem that the accuracy of the result is low because hole bending tends to occur. According to the present invention, the camera-equipped rod can be penetrated to a deep portion while maintaining the verticality, and the presence of the curable material liquid is confirmed based on respective images taken at a plurality of points having different depths. Thus, not only the effective diameter of the improved body but also the continuity can be reliably confirmed immediately after the construction. Therefore, even if a problem is found in the continuity of the ground improvement body, it is possible to immediately take measures such as re-construction, and there is a situation in which additional construction or another type of auxiliary construction method is performed after the completion of the construction period. Does not occur.

  In order to solve the above problems, the effective diameter confirmation method for a ground improvement body of the present invention further includes an inclinometer and an orientation meter for detecting the inclination angle and orientation of the camera-attached rod in the ground, respectively. And a position detecting step of detecting the position of the camera in the ground based on the inclination angle information and the azimuth information obtained from the inclinometer and the azimuth meter.

  As described above, the effective diameter confirmation method of the ground improvement body of the present invention is such that the rod with camera penetrates into the soft muddy ground improvement body before the hardening material liquid is hardened, so that the verticality is maintained. It is possible to penetrate the rod with camera to the deep part. However, when passing through the normal ground from the ground surface to the upper end of the ground improvement body, there is a case where an inclination or a azimuth shift occurs. In addition, even after reaching the ground improvement body, a slight inclination or misalignment may occur. In order to confirm the effective diameter of the ground improvement body with higher accuracy, it is necessary to accurately detect and correct immediately the inclination and the deviation of the azimuth. According to the present invention, the camera-equipped rod is provided with an inclinometer and an azimuth meter for detecting the inclination angle and orientation of the camera-equipped rod in the ground, respectively. The position of the camera in the ground can be detected. By correcting the position of the camera in the ground based on the obtained position information, the effective diameter of the ground improvement body can be confirmed with very high accuracy.

  In order to solve the above-mentioned problem, the effective diameter confirmation method of the ground improvement body of the present invention sprays a hardening material liquid colored so as to be distinguishable from earth and sand from the injection nozzle of the injection rod, or injection of the injection rod Colored curing in the image confirmation process by spraying from the colorant spray nozzle a colorant that colors the curing material liquid so that it can be distinguished from earth and sand to the cured material liquid sprayed from the nozzle. It is characterized by confirming the presence of the material liquid.

  Depending on the type and condition of the earth and sand on which the ground is to be improved, it may be difficult to distinguish the earth and sand and the hardening material liquid in the image. In addition, in the vicinity of the limit of the hardener liquid, the ratio of the hardener liquid to the earth and sand becomes small, and it may be difficult to identify the presence of the hardener liquid. According to the present invention, since the hardening material liquid is colored so as to be distinguishable from the earth and sand, the presence of the hardening material liquid can be easily and reliably confirmed in the image confirmation process, and the effective diameter of the ground improvement body can be more accurately determined. Can be confirmed.

  In order to solve the above problems, the effective diameter confirmation method for the ground improvement body of the present invention further includes a colorant spraying port for spraying the colorant, and the camera-attached rod is attached to the front stage of the image display process. It includes a coloring process for coloring the curing material liquid by spraying a coloring agent for coloring the curing material liquid from the rod colorant spraying port so that it can be distinguished from earth and sand. In the image confirmation process, the presence of the colored curing material liquid is detected. It is characterized by confirming. At this time, it is preferable that the colorant spraying port is positioned below the camera of the camera-equipped rod and is provided so as to spray the colorant over the area photographed by the camera.

  According to the present invention, it is only necessary to spray the colorant from the colorant spray port provided on the rod with the camera so that only the curing material liquid in the region photographed by the camera is colored. The amount is small. Further, since the image is taken while moving (penetrating) the rod with camera downward, the colored material is sprayed and the curing material liquid is colored, and then the camera passes through and the colored area is taken. Can work efficiently. Furthermore, since the hardener liquid is colored so as to be distinguishable from the earth and sand, even if it is difficult to distinguish the earth and sand from the hardener liquid in the image, the presence of the hardener liquid can be easily and reliably confirmed in the image confirmation process. Can be confirmed. Therefore, the effective diameter of the ground improvement body can be confirmed with higher accuracy without increasing the cost and the working time.

  According to the effective diameter confirmation method of the ground improvement body of the present invention, a rod with a camera is inserted into a soft muddy ground improvement body before the hardening material liquid is hardened, and an image photographed at a predetermined depth is obtained in real time. Since it is displayed on the monitor on the ground and the presence of the hardening material liquid is confirmed, the effective diameter of the ground improvement body formed by the high-pressure jet stirring method can be easily and accurately confirmed immediately after the construction.

  Hereinafter, the effective diameter confirmation method of the ground improvement body of this invention is demonstrated. The present invention is a method for confirming the effective diameter of a ground improvement body created by a high-pressure jet stirring method. The high-pressure jet agitation method is a method in which after the ground is drilled to a predetermined depth using an injection rod, the injection rod mounted on the lower end of the injection rod is pulled up while rotating or swinging the injection rod, A method of forming a cylindrical or fan-shaped ground improvement body by stirring and mixing the hardened material liquid and the soft soil forming the ground while cutting the existing ground by injecting the liquid in the horizontal direction with ultra high pressure. It is. In this specification, the “effective diameter of the ground improvement body” means the distance between the point where the presence of the hardening material liquid injected from the injection nozzle of the injection rod is confirmed and the penetration position of the injection rod at that depth. .

  Initially, the outline of the effective diameter confirmation method of the ground improvement body of this invention is demonstrated using FIG. 1 and FIG.

  FIG. 1 is an explanatory diagram of an effective diameter confirmation method for a ground improvement body of the present invention. As shown in FIG. 1, the effective diameter confirmation method of the ground improvement body of the present invention is to cure before the hardening material liquid of the ground improvement body 60 formed by injecting the hardening material liquid by high-pressure jet stirring method is hardened. At a point on the ground surface 50 that is a predetermined distance away from the penetration position 51 of the injection rod for injecting the material liquid (for example, a distance at which the hardened material liquid can be reached at the design stage: design reach distance 52). The camera-equipped rod 1 having a camera 11 capable of photographing the image is inserted into the ground, and an image photographed by the camera 11 is displayed on the monitor 15 on the ground, and the presence of the hardening material liquid is confirmed for the image photographed at a predetermined depth. By confirming, the effective diameter of the ground improvement body 60 can be simply and accurately confirmed immediately after construction.

  FIG. 2 is an explanatory view showing an example of a method of penetrating a rod with a camera into the ground in the effective diameter confirmation method for a ground improvement body of the present invention. As shown in FIG. 2, the static cone penetration machine 100 is installed at the penetration position of the rod 1 with camera. The camera-equipped rod 1 including the camera 11 is attached to the lifting device 101 of the static cone penetrating machine 100 and is inserted into the normal ground 61 by the operation of the lifting device 101. In order to penetrate the rod 1 with camera 1 to the lower end of the ground improvement body 60 formed under the normal ground 61, a connecting rod 70 is sequentially added to the rod 1 with camera. A necessary number of connecting rods 70 are prepared in advance, and a video cable 14 for transmitting an image captured by the camera 11 to the monitor 15 is passed through each connecting rod 70. Each rod can be screwed.

  Next, an example of the camera-equipped rod 1 used in the present invention will be described with reference to FIGS. Fig.3 (a) is explanatory drawing which shows an example of the rod with a camera used for this invention, (b) is XX sectional drawing of (a). FIG. 4 is a front view of the camera-equipped rod of FIG.

  As shown in FIGS. 3A, 3B and 4, this camera-equipped rod 1 has a camera 11 and a light source 12 capable of photographing the ground inside a camera housing rod 10 having a cone-shaped tip. A window 13 is provided in front of the camera 11. One light source 12 is arranged on each side of the camera 11. The light emitted from the light source 12 irradiates the outer earth and sand through the window 13, and the area where the light is emitted is photographed by the camera 11, so that the state of the earth and sand in the ground can be easily visually observed on the ground monitor 15. become. A metal such as iron or aluminum is used for the rod and the tip. Since the outside of the window 13 is in contact with the earth and sand, a transparent material (for example, sapphire) that is not easily damaged is used. The image captured by the camera 11 may be either a still image or a moving image, and the captured image is displayed on a ground monitor 15 (not shown) via a video cable 14 connected to the camera 11.

  Subsequently, another example of the camera-equipped rod 1 used in the present invention will be described with reference to FIGS. 5 and 6. Fig.5 (a) is explanatory drawing which shows the other example of the rod with a camera used for this invention, (b) is the YY sectional view taken on the line (a), (c) is (a). FIG. FIG. 6 is a front view of the camera-equipped rod of FIG.

  As shown in FIGS. 5 (a), (b), (c) and FIG. 6, this camera-equipped rod 1 has a position sensor accommodation rod 20 connected to the upper part of the camera accommodation rod 10 and a static cone at the lower part. A penetration test cone 30 is connected. In addition to the camera 11 and the light source 12, the camera housing rod 10 is provided with a colorant spray port 41, to which a colorant transport tube 42 is connected.

  A position sensor 21 including an inclinometer 22 and an azimuth meter 23 is housed in the position sensor housing rod 20. A position information transmission cable 24 is connected to the position sensor 21, and information on the inclination angle and direction detected by the inclinometer 22 and the azimuth meter 23 is transmitted to a ground computer (not shown). In the computer, the transmitted tilt angle and azimuth information is processed as necessary and displayed on the display.

  The types of the inclinometer 22 and the azimuth meter 23 constituting the position sensor 21 are not particularly limited, but a suitable inclinometer 22 may be, for example, a capacitive inclinometer. Moreover, as a suitable compass 23, an optical gyro can be mentioned, for example. The capacitive inclinometer and the optical gyro are both resistant to shock and vibration, and can be said to be instruments that are suitable for being housed in the position sensor housing rod 20. In order to eliminate the influence of magnetism on the position sensor 21, a material that does not have magnetism, such as aluminum or stainless steel, is used for the position sensor receiving rod 20.

  Since the camera-equipped rod 1 includes the position sensor 21, the position of the camera 11 in the ground can always be accurately detected, and if there is a deviation from the vertical direction, the position can be corrected immediately. The effective diameter of the improved body 60 can be confirmed.

  As the static cone penetration test cone 30, a two-component cone capable of measuring tip resistance and circumferential friction is suitably used. The tip resistance and the peripheral surface friction are measured by each load meter 31 built in the cone 30 for static cone penetration test. A load data transmission cable 32 is connected to each load cell 31, and the obtained tip resistance and circumferential friction data are transmitted to a ground computer (not shown). In the computer, the transmitted tip resistance and circumferential friction information is processed as necessary and displayed on the display. The static cone penetration test cone 30 is not limited to a two-component cone as long as it can measure any one of tip resistance and peripheral surface friction.

  By providing the static cone penetration test cone 30 in the camera-equipped rod 1, the tip resistance and the circumferential friction can be measured. From the change in these values, for example, by the decrease in the resistance value and the friction value, It can be estimated that the upper end of the ground improvement body 60 has been passed through the ground 61.

  The monitor for displaying an image taken by the camera 11, the display for displaying position information, and the display for displaying data on tip resistance and peripheral friction may be different, but one or two displays May be displayed in combination.

  The colorant spraying port 41 provided in the camera housing rod 10 is for spraying a colorant for coloring the hardener liquid so as to be distinguishable from earth and sand. Even if it is difficult to distinguish the earth and sand in the image from the earth and sand by spraying the colorant from the colorant spraying port 41 and coloring the earth and sand in such a way that it can be distinguished from the earth and sand. Can be easily and reliably confirmed.

  As shown in FIG. 6, the colorant spraying port 41 is provided directly below the window 13. Since the image is photographed while moving (penetrating) the rod with camera 1 downward, the colorant spraying port 41 is provided at this position, so that the colorant is sprayed on the area photographed by the camera 11, and the curing material liquid The area where the camera 11 is colored can be photographed after the is colored. Therefore, since the image immediately after coloring can be used without lowering the working efficiency, the presence of the curing material liquid can be easily and reliably confirmed. Moreover, since it is sufficient to color a narrow range, a small amount of colorant is sufficient. Note that the position where the colorant spraying port 41 is provided is not limited to the position immediately below the window 13, but is provided below the camera 11 so as to spray the colorant on the area photographed by the camera 11. Just do it.

  The colorant sprayed from the colorant spraying port 41 is supplied from the ground via the colorant transport tube 42. Moreover, it is preferable to spray using a suitable pump such as a manual pump under a moderate pressure. Details of the coloring method and the colorant will be described later.

  Next, the procedure of the effective diameter confirmation method of the ground improvement body of this invention is demonstrated.

  The effective diameter confirmation method of the ground improvement body of this invention is implemented after the construction of the ground improvement body 60 by a high-pressure jet stirring method, and before the hardening | curing material liquid injected in the ground hardens | cures. Therefore, it is preferably performed during the day of construction of the ground improvement body 60 by the high-pressure jet stirring method, and more preferably performed immediately after the construction.

  First, the penetration position of the rod 1 with camera is set. FIG. 7 is an explanatory view showing the penetration position of the camera-equipped rod according to the present invention. As shown in FIG. 7, when the ground improvement body 60 is created by the high-pressure jet agitation method, the reach distance of the hardening material liquid is designed in advance (design reach distance 52), and part of the ground improvement body 60 Is designed to have a portion (lap portion) overlapping with the adjacent ground improvement body 60. And if the hardening | curing material liquid reaches | attains as designed, the effective diameter of the ground improvement body 60 created will become equal to the design reach distance 52, and it can wrap with the adjacent ground improvement body 60 and can form a wall reliably. . Therefore, the first penetration position A of the rod 1 with camera 1 is set based on the penetration position 51 of the injection rod for injecting the curing material liquid, the design reach distance 52, and the design position of the adjacent ground improvement body 60. The first penetration position A is set at the point of the design reach distance 52 even for the ground improvement body that does not overlap with the adjacent ground improvement body 60. Although FIG. 7 shows the ground improvement body 60 having a cross-sectional shape in which two substantially sector shapes are connected, the penetration position of the camera-equipped rod 1 is similarly set in the case of the cylindrical ground improvement body 60.

  The second penetration position B shown in FIG. 7 is a position set to confirm the effective diameter next when the effective diameter cannot be confirmed at the first penetration position A. The third penetration position C is a position that is set to confirm the actual reach distance of the curing material liquid when the effective diameter is confirmed at the first penetration position A. How far the second penetration position B or the third penetration position C is set from the first penetration position A is appropriately determined with reference to the confirmation result of the effective diameter at the first penetration position A. In this way, by confirming the effective diameter of the ground improvement body 60 at a plurality of locations, it is possible to accurately grasp the reach of the curing material liquid. The effective diameter confirmation results obtained immediately after construction can be used immediately for feedback on construction specifications, and by reviewing construction specifications as necessary, unnecessary costs can be saved and work efficiency can be improved. Is possible.

  After the construction of the ground improvement body 60 by the high-pressure jet stirring method is completed, the penetration of the rod with camera 1 is started. Here, although the procedure in the case of implementing the effective diameter confirmation method of the ground improvement body of this invention using the rod 1 with a camera shown to Fig.5 (a) is demonstrated, the rod 1 with a camera other than this may be used. It can be carried out according to the following procedure.

  First, the static cone penetration machine 100 for penetrating the rod 1 with camera into the ground is installed at the penetration position of the rod 1 with camera (see FIG. 2). As already described, the camera-equipped rod 1 is attached to the lifting device 101 of the static cone penetrator 100. Further, the necessary number of connecting rods 70 are prepared, and the video cable 14, the position information transmission cable 24, the load data transmission cable 32, and the colorant transport tube 42 are passed through all the connecting rods 70.

  When the rod with camera 1 is mounted on the lifting device 101 of the static cone penetrator 100, it is confirmed that the tip of the rod with camera 1 matches the set penetration position. Before the penetration of the rod 1 with camera, the camera 11, the light source 12, the monitor 15, the position sensor 21, a computer (including a display) connected thereto, a load meter 31 of the static cone public test cone 30, and And it confirms that the computer (a display is included) connected with this operate | move normally, these devices are made into an operation state, and penetration of the rod 1 with a camera is started. At this time, the depth display of the computer display connected to the position sensor 21 is confirmed.

  When the lifting device 101 of the static cone penetrating machine 100 is lowered, the camera-attached rod 1 passes through the normal ground 61 from the ground surface 50 and penetrates into the ground improvement body 60 (camera-attached rod penetration step). The penetration is performed while the connecting rods 70 are sequentially added. Whether the rod 1 with camera passes through the normal ground 61 and reaches the ground improvement body 60 depends on changes in the tip resistance value and the peripheral friction value obtained from the load meter 31 of the static cone penetration test cone 30 ( (Decrease), the penetration depth of the rod 1 with camera, and the image taken by the camera 11 can be confirmed.

  Here, when the normal ground 61 from the ground surface 50 to the upper end of the ground improvement body 60 is a gravel ground or a high-strength ground, before the penetration of the rod 1 with a camera is started, the static cone penetrating machine 100 is used. It is preferable to drill another hole between the ground surface 50 and the upper end of the ground improvement body 60 by attaching another ground excavating tool to the ground. The excavation tool to be used is not particularly limited. For example, a general ground excavation tool such as an auger bit can be used. When drilling using a ground excavator, after the drilling is completed, the ground excavator is pulled up and removed from the cone penetrating device, and the camera-equipped rod 1 is attached instead. The rod with camera 1 passes through the drilled hole and penetrates into the ground improvement body 60. Thus, when the normal ground 61 is drilled in advance, the camera-equipped rod 1 penetrates into the soft muddy ground improvement body 60 from the beginning, so the camera-equipped rod 1 used has a cone-shaped tip. It may be a thing which does not have.

  The position information obtained from the position sensor 21 housed in the position sensor housing rod 20 is always displayed on a computer display connected to the position sensor 21. When the position of the camera 11 is accurately detected, the camera-attached rod The position information is acquired by temporarily stopping the penetration of position 1 (position detection step). When a deviation from the vertical direction is recognized, (1) change the penetration position of the rod 1 with camera and repeat the penetration, (2) correct the position by rotating the rod 1 with camera, etc. ( 3) The correct position of the camera 11 can be calculated from the tilt angle information and the azimuth information without correcting the position, and the effective diameter can be confirmed from the image obtained at that position. As a result, the effective diameter of the ground improvement body 60 can be confirmed with very high accuracy.

  By operating the camera 11 and the light source 12, an image is displayed on the ground monitor 15 via the video cable 14 (image display process). Further, an image recording device such as a video deck is connected to the monitor 15 and the obtained image is recorded on a recording medium. Usually, since the penetration of the camera-equipped rod 1 is started with the camera 11 and the light source 12 activated, an image from the ground surface 50 to the lower end of the ground improvement body 60 is displayed on the monitor 15 and recorded on the recording medium. .

  The depth for checking the image is determined in advance, and once the rod with camera 1 reaches the planned depth, the penetration is stopped once, and whether or not the hardening material liquid is present in the image displayed on the monitor 15 is determined in real time. (Image confirmation process). Confirmation can be made visually. Commercially available image analysis software or the like can also be used. The presence of the curable material liquid can be determined by a change in color tone, a change in particle size, mixing of bubbles, or the like. After confirmation, the result is recorded, and the rod with camera 1 is penetrated to the next scheduled depth for confirmation. By repeating this procedure to the lower end of the ground improvement body 60, the effective diameter of the ground improvement body 60 can be confirmed, and the continuity of the ground improvement body 60 can also be confirmed. In addition, the lower end of the ground improvement body 60 means the lower end of the ground improvement body 60 in a design stage, and the depth of a lower end corresponds with the depth which started injection of the hardening material liquid from the injection rod. Therefore, whether or not the camera-equipped rod 1 has reached the lower end of the ground improvement body 60 is confirmed by the depth.

  In addition, instead of stopping the camera-equipped rod 1 at each confirmation scheduled depth and confirming the image each time, the presence of the curable liquid in the image at each confirmation planned depth is confirmed using the image recorded on the recording medium. Also good.

  Depending on the type and condition of the earth and sand on which the ground is to be improved, it may be difficult to determine the presence of the hardening material liquid in the image due to a change in color tone, a change in particle size, mixing of bubbles, or the like. Moreover, in the vicinity of the design reach distance 52 of the hardener liquid, the ratio of the hardener liquid to the earth and sand becomes small, and it may be difficult to identify the presence of the hardener liquid. In such a case, the presence of the curable material liquid in the image can be easily confirmed by coloring the curable material liquid to be distinguishable from earth and sand. This camera-equipped rod 1 is provided with a colorant spraying port 41 in the camera housing rod 10, and the colorant can be sprayed from the colorant spraying port 41 to color the curing material liquid. Before being photographed by the camera 11, a colorant is sprayed on the area to be photographed, and the curing material liquid is colored (coloring step). Thereafter, the camera 11 captures the colored area, and the image is displayed on the monitor 15.

  Thus, the confirmation of the effective diameter at the first penetration position A is completed. When the effective diameter cannot be confirmed at the first penetration position A, the effective diameter is continuously confirmed at the second penetration position B. When the effective diameter can be confirmed at the first penetration position A, the effective diameter is continuously confirmed at the third penetration position C.

  Next, a method for coloring the hardener liquid so as to be distinguishable from earth and sand using a colorant and the colorant used will be described in detail.

  As a first method for coloring the curing material liquid, there is a method of adding a colorant when preparing the curing material liquid. Moreover, as a 2nd method for coloring a hardening material liquid, the method of spraying a coloring agent from the coloring agent injection nozzle of an injection | pouring rod in the ground, and stirring and mixing in a hardening material liquid and the ground is mentioned. When these methods are used, the entire hardening material liquid is colored so as to be distinguishable from earth and sand.

  As the colorant used in each of the above coloring methods, general dyes and pigments can be suitably used. When the hardener liquid contains a cement-based solidifying material, it is preferable to select a colorant that does not change its color tone or does not fade under an alkaline atmosphere. For example, colored slag fine particle powder is a suitable colorant in that it functions as a fine aggregate of mortar and does not fade in an alkaline atmosphere. The colored slag can be obtained by the method described in JP-A-4-224146.

  As a third method of coloring the curing material liquid, there is a method of coloring the periphery of the range photographed by the camera 11 when penetrating the rod 1 with camera. If this third method is used, a small amount of colorant is sufficient.

  When the curing material liquid is colored by the third method, the camera-equipped rod 1 provided with the colorant spraying port 41 is used as shown in FIGS. The camera-equipped rod 1 is provided so that the colorant spraying port 41 is located below the camera 11 and sprays the colorant onto the area photographed by the camera 11. Since the image is photographed while being moved (penetrated), the colored region is sprayed and the curable material liquid is colored, and then the camera 11 passes through to photograph the colored region, so that the work can be efficiently performed. .

  The colorant used in the third method is not particularly limited, and general dyes and pigments can be used. In addition, when the hardener liquid contains a cement-based solidifying material, the hardener liquid becomes alkaline, so a pH indicator can be used as a colorant. The pH indicator is suitable as a colorant used in a method of coloring a narrow range and photographing immediately after the coloring (third coloring method). Preferable pH indicators in the present invention include phenolphthalein. Phenolphthalein is colorless in the acidic and neutral regions and red in the alkaline region, so the region where the hardener liquid containing cement-based solidification material and earth and sand are mixed is colored red, and the hardening containing the cement-based solidification material. The earth and sand in the area where the material liquid has not reached is not colored. In addition, since phenolphthalein exhibits a red color instantaneously in an alkaline atmosphere, it is not necessary to consider the time lag until coloring. Therefore, it is possible to easily and reliably confirm the presence of the curing material liquid in the photographed image immediately after the phenolphthalein spraying.

It is explanatory drawing of the effective diameter confirmation method of the ground improvement body of this invention. It is explanatory drawing which shows an example of the method of penetrating the rod with a camera in the ground in the effective diameter confirmation method of the ground improvement body of this invention. (A) is explanatory drawing which shows an example of the rod with a camera used for this invention, (b) is XX sectional drawing of (a). It is a front view of the rod with a camera of Fig.3 (a). (A) is explanatory drawing which shows the other example of the rod with a camera used for this invention, (b) is the YY sectional view taken on the line of (a), (c) is (a). FIG. It is a front view of the rod with a camera of Fig.5 (a). It is explanatory drawing which shows the penetration position of the rod with a camera in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rod with camera 10 Camera accommodation rod 11 Camera 12 Light source 13 Window 14 Video cable 15 Monitor 20 Position sensor accommodation rod 21 Position sensor 22 Inclinometer 23 Orientation meter 24 Position information transmission cable 30 Cone for static cone penetration test 31 Load meter 32 Load data transmission cable 41 Colorant spray port 42 Colorant transport tube 50 Ground surface 51 Injection rod penetration position 52 Design reach 60 Ground improvement body 70 Connecting rod 100 Static cone penetration machine 101 Lifting device

Claims (6)

It is a method for confirming the effective diameter of the ground improvement body formed by injecting the curing material liquid from the injection nozzle of the injection rod penetrated to a predetermined depth in the ground by the high-pressure injection agitation method, and stirring and mixing,
Before the curing material liquid is cured, at a point away from the penetration position of the injection rod at a predetermined distance, a camera-attached rod penetrating step of penetrating into the ground a camera-equipped rod having a camera capable of photographing the ground;
An image display step of displaying an image captured by the camera on a ground monitor;
A method for confirming the effective diameter of a ground improvement body, comprising an image confirmation step for confirming the presence of a hardening material liquid for an image photographed at a predetermined depth.   The method for confirming an effective diameter of a ground improvement body according to claim 1, wherein in the image confirmation step, the presence of the hardening material liquid is confirmed for each of images taken at a plurality of points having different depths. The rod with camera further comprises an inclinometer and an azimuth meter for detecting the inclination angle and orientation of the rod with camera in the ground, respectively.
The ground improvement body according to claim 1 or 2, further comprising a position detection step of detecting a position of the camera in the ground based on inclination angle information and orientation information obtained from the inclinometer and the compass. Effective diameter confirmation method.   The hardened material liquid colored to be distinguishable from earth and sand is sprayed from the injection nozzle of the injection rod, or the hardened material liquid injected from the injection nozzle of the injection rod can be distinguished from the earth and sand. The presence of a colored curable material liquid is confirmed in the image confirmation step by spraying a colorant to be colored from a colorant injection nozzle to color the curable material liquid. 4. The effective diameter confirmation method of the ground improvement object of any one of 3. The rod with camera further includes a colorant spraying port for spraying a colorant,
In the preceding stage of the image display step, including a coloring step of coloring the curing material liquid by spraying a coloring agent that colors the curing material liquid so as to be distinguishable from earth and sand from the coloring agent spray port of the rod with camera.
The method for confirming the effective diameter of the ground improvement body according to any one of claims 1 to 3, wherein in the image confirmation step, the presence of a colored curable material liquid is confirmed.   The said colorant spraying port is located below the camera of the said rod with a camera, and is provided so that the said colorant may be sprayed on the area | region image | photographed with the said camera. Effective diameter confirmation method of ground improvement body.

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