JP2007224645A - Method of constructing improved slope ground in execution of soil improvement, and multiple soil improving machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To save the usage of a soil improving agent for use in the improved slope ground developed in the ground, by forming steps at upper and lower edges of ground units protruding from a slope. <P>SOLUTION: The improved slope ground is developed by using a multiple soil improving machine which is set up by combining a plurality of soil improving machine units each having a rotation drive unit at an upper portion of an excavation rod having an excavation head at the tip of the same, so that the rotation drive units are fitted into a support frame, and arranging the pairing excavation rods side by side in a longitudinal direction. The improved slope ground is formed by successively arranging the improved ground units in the ground. Specifically tip of the respective excavation heads are located so as to be different in height based on an inclination angle of the improved slope ground. Then the steps which are unimproved areas are formed at the upper and lower edges of the ground units based on the difference in height. Thus by the formation of the unimproved areas of the ground units, the usage of the soil improving agent is saved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for continuously forming a unit ground having improved ground and constructing an inclined improved ground in the ground, and a multiple ground improving device used for the construction method.

  In ground improvement, a multiple ground improvement device is used in which a plurality of excavation rods are simultaneously driven to excavate a soft ground and agitate and knead excavated soil and a ground improvement agent. In an ordinary multiple ground improvement device, the length of all the excavation rods is made the same so that the excavation head at the tip is at the same height so that no step is generated under the improvement ground.

Some drilling heads have a difference in height, but as a means to overlap the drilling holes, when the distance between the rods is reduced, the excavation blades and stirring blades at the same position are moved up and down so that they do not interfere with each other. The level difference caused by the height difference is assumed to be within an allowable range.
Japanese Patent No. 2920470 JP 2002-30650 A

  For ground improvement, in addition to excavating the soft ground from the ground to a set depth to improve the entire ground, the ground adjacent to the existing structure may be improved to the slope. 6 (A) and 6 (B), in order to construct a facility on the ground below the ground surface, the ground away from the ground of the ground 1 is improved, and the improved ground 2 is not yet developed. The improved ground may be excavated. In this case, the construction ground 4 around the improved ground 2 in the ground is often ground improved to the slope improved ground 3.

In the conventional multiple ground improvement device, since the excavation heads are at the same height position, between the upper and lower construction lines L ₁ and L ₂ which are excavated from the ground and inclined in the ground. When the ground improved by the one excavation process is used to improve the ground to the slope improved ground 3, the unit ground 3B ', 3C', which is repeatedly constructed upward from the unit ground 3A '. ...... Upper and lower ends of 3N project outside the upper and lower construction lines that become the slope of the slope-improved ground 3. In addition, there is a difference in height between the unit ground that has been previously constructed and the unit ground that has been constructed adjacently along the construction line, and this remains as a large step on the slope of the slope-improved ground 3.

  In the ground improvement, the ground between the construction lines only needs to be improved, and in the slope improvement ground 3, the improved portion protruding outward from the upper and lower construction lines becomes extra. In some cases, when the unimproved ground on the improved ground 2 is excavated and removed after the improved construction, the ground may be cut and removed along the slope to form a flat slope or slope on the slope improved ground 3. Due to the ground improvement at the upper and lower ends, the amount of the ground improvement agent used in the slope improved ground 3 with respect to the volume of the improved ground is larger than that in the case of the flat improved ground, which is one cause of high cost.

  This invention was conceived in order to reduce the amount of ground improver used in the construction of the above-mentioned slope improved ground, the purpose of which protrudes outside the upper and lower construction lines that become the slope, the extra improved ground The construction method of the slope improvement ground and the multiple ground improvement device in the new ground improvement that reduces the amount of ground improvement agent used by the level difference at the upper and lower ends of the unit ground. There is to do.

  According to the construction method of the present invention for the above purpose, a plurality of single ground improvement devices having a rotary drive device at the top of a drilling rod having a drilling head at the tip are assembled, and a rotary drive device is assembled to a support frame. In order to construct the slope improved ground in the ground by continuously forming the ground improved unit ground by the multiple ground improvement device with drilling rods arranged in front and back, the slope improved ground at the tip position of a pair of front and rear drilling heads The height difference is provided based on the inclination angle, and the step difference is formed as an unimproved portion on each upper and lower end portion of the unit ground due to the height difference, and the amount of ground improver used is reduced by the unimproved portion. That's it.

  Further, the multiple ground improvement device of the present invention is a plurality of single ground improvement devices equipped with a rotation drive device on the upper part of a drilling rod having a drilling head at the tip, and a rotation drive device is assembled to the support frame, It is a multiple ground improvement device that installs a pair of excavation rods in front and back, continuously forms a unit ground improved by the excavation rod, and constructs an inclined improved ground in the ground, A height difference is provided at the tip position based on the inclination angle of the slope improved ground, and the height difference is provided by adding a relay rod having the same length as the height difference to one of the excavation rods. is there.

  In the construction method according to the present invention, the upper and lower end portions of the unit ground protruding from the slope are formed small by the unimproved portion generated by the stepped portion, whereby the usage amount of the ground improving agent is reduced accordingly. Since this reduction extends to the entire slope, the amount of ground improvement agent used in the slope improvement ground is greatly reduced, and the construction cost is reduced.

  In the multiple ground improvement device of the present invention, since the height of the tip of the excavation head is provided by the joint of the relay rod, the length corresponding to the inclination angle can be applied even in the construction of the inclination improvement ground having different inclination angles. It is only necessary to change to a relay rod, and the relay rod can be removed to align the tip position, so that it can be used as a normal multiple ground improvement device in addition to the construction of the slope improvement ground.

  In the figure, reference numeral 10 denotes a multiple ground improvement device. Four units of a single ground improvement device having rotary drive devices 12 and 12 'above the hollow excavation rods 11 and 11' (only two front and rear units are shown in the figure). , Each rotary drive device 12, 12 'is assembled in a square shape inside a quadrilateral support frame 13 having a normal structure, and each excavating rod 11, 11' is provided in parallel in the front-rear and left-right directions. In this ground improvement device 10, a support frame 13 is attached to a guide 32 vertically installed on a work rod 31 of a crawler 30, and a pulley 14 provided on the upper portion is attached to an operation rope 33 suspended from the top of the work rod 31. It is hung so that it can be moved up and down.

  As shown in FIG. 2, excavation agitation rods 16 and 16 ′ having excavation heads 15 and 15 ′ having discharge ports are connected to the rod ends of the excavation rods 11 and 11 ′ by joints 17 and 17 ′. It is. Excavation heads 18 and 18 'are attached to the tips of the excavation heads 15 and 15', and excavation blades 19 and 19 'are attached to both sides. Excavation blades 19 and a pair of agitation blades 20 and 20 ′ having the same length as 19 ′ are provided on the side surfaces of the excavation agitation rods 16 and 16 ′ in different directions and projecting alternately. The agitating blades 20 and 20 'agitate and knead the ground improving agent discharged from the excavating heads 15 and 15' through the excavated soil and the excavating rod, thereby improving the ground. Further, the excavation rods 11 and 11 ′ are rotatably held by a plate-like connecting member 21 attached over the joints 17 and 17 ′.

  In the multi-panel improvement device 10, the length of the excavation rod 11.11 'up to the excavation heads 15 and 15' at the front end is changed between the front row and the rear row, and the height of the excavation head 15.15 'is changed to the mutual front end position. A difference A is provided. This height difference A is determined based on the inclination angle of the inclined improved ground 3 constructed in the ground. In the figure, a relay rod 11a having a length corresponding to the height difference A is added between the front row excavation rod 11 and the excavation stirring rod 16, and the front row is provided longer than the rear row. Although omitted in the drawing, a relay rod may be added to the rear row of excavation rods so that the rear row is longer than the front row.

FIG. 3 is an explanatory diagram when the slope improvement ground 3 is constructed in the ground by the multiple ground improvement device 10. In the figure, the multiple ground improvement device is omitted, but the excavation rods 11 and 11 'are simultaneously rotated and excavated by the excavation ground in the same manner as in the normal construction method, and the construction line L is previously set to be inclined in the ground. The construction ground 4 between ₁ and the lower construction line L ₂ is kneaded with the excavated soil while discharging the ground improver from the upper construction line L ₁ from the excavation head 15, and then the ground to the lower construction line L _2. Improve. The improved ground by this one step is used as the unit ground 3A, and the same process is repeated upward along the construction line to complete the slope improved ground 3 by the continuous construction of the unit grounds 3A, 3B, 3C.

  In the multiple ground improvement device 10, since the front and rear excavation heads 15, 15 ′ have the height difference A, the level difference A ′ equivalent to the height difference A has upper and lower ends of the unit grounds 3 A, 3 B, 3 C. It occurs in the part. Further, the step A ″ between the unit ground 3A formed in advance and the unit ground 3B formed adjacently along the construction line is also formed at the same height as the step A ′. These steps A ′ and A ″. The part of is located alternately with the improved part as an unreformed part on the outside of the construction line that becomes the slope, but in the ground improvement, it is only necessary to improve the construction ground 4 between the upper and lower construction lines, so the upper and lower ends projecting outside the construction line The portion becomes extra, and even if the portion of the step A ′ is left unmodified, there is no particular problem.

  As shown in FIG. 4, when the excavation rods 11, 11 'are made the same length and the excavation heads 16, 16' have the same tip position, the construction is performed in the same state as a conventional multistage ground improvement device. As shown in FIG. 5, the upper and lower ends of the unit grounds 3A ′, 3B ′, and 3C ′ are flatly improved to protrude from the slope, and only the step A ″ with the adjacent unit ground is formed high. 3, a step portion A ′ formed from the height difference of the tip position is formed, and the portion is not improved and the ground improver is not injected, so each unit ground 3A ′. , 3B ′, 3C ′ are not formed with broken lines that occupy 1/2 of the cross-sectional area of the upper and lower end portions.

  In short, according to the present invention, the upper and lower ends of the unit ground protruding from the slope by the unreformed portions of the upper and lower ends by the step A ′ are formed to be halved, thereby reducing the use amount of the ground improvement agent accordingly. Is to do. This reduction in the amount of use extends over the entire slope where the unit ground is continuously formed, so that the amount of the ground improver used in the slope improved ground is greatly reduced, and the construction cost is also reduced. Further, since the upper and lower end portions are formed small over the entire slope, the cutting process is facilitated.

It is a side view of a crawler provided with the multiple ground improvement device concerning this invention. It is a side view of the excavation rod front-end | tip part of a multiple-panel-type board improvement apparatus similarly. It is construction explanatory drawing of the inclination improvement ground by the multiple ground improvement device concerning this invention. It is a side view of the excavation rod front-end | tip part which aligned the front-end | tip position of an excavation head equally. It is construction explanatory drawing of the inclination improvement ground by the excavation head same as the above. It is explanatory drawing at the time of constructing the inclination improvement ground in the ground with the conventional multiple ground improvement device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ground 2 Improved ground 3 Inclined improved ground 4 Construction ground 10 Multiple-type ground improvement device 11, 11 'Excavation rod 11a Relay rod 12, 12' Rotation drive device 13 Support frame 15, 15 'Excavation head 16, 16' Excavation stirring Rod 17, 17 'Joint 18, 18' Excavation blade 19, 19 'Excavation blade 20, 20' Agitation blade 21 Connecting member 30 Crawler 31 Work rod 33 Operation cord

Claims (2)

Multiple units of a single ground improvement device equipped with a rotary drive device on the upper part of a drilling rod having a drilling head at the tip, a rotary drive device attached to a support frame, and a pair of drilling rods arranged side by side When constructing the slope improved ground in the ground by continuously forming the unit ground improved ground by the type ground improvement device,
The tip position of the pair of front and rear excavation heads is provided with a height difference based on the inclination angle of the inclined improved ground, and a step that becomes an unreformed portion is formed at each upper and lower end portion of the unit ground due to the height difference. The construction method of the slope improvement ground in the ground improvement characterized by reducing the usage-amount of a ground improvement agent by. A plurality of single ground improvement devices equipped with a rotary drive device at the top of a drilling rod having a drilling head at the tip, a rotary drive device attached to the support frame, and a pair of drilling rods arranged side by side, A multiple ground improvement device that continuously forms unit ground improved by excavation rods and constructs inclined improved ground in the ground,
A height difference is provided at the tip position of the pair of front and rear excavation heads based on the inclination angle of the inclined improved ground, and the height difference is provided by adding a relay rod of the same length as the height difference to one of the excavation rods. A multiple ground improvement device for slope improvement ground construction in ground improvement characterized by

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