JP5235748B2 - Wall metal fittings and underground continuous wall construction method - Google Patents

Description

  The present invention relates to a lower H-section steel (this lower section includes a structure composed of a plurality of H-section steels. The main points are the steel parts excluding the upper H-section steel to be separated. The same applies hereinafter). A connecting bracket for detachably connecting the upper H-shaped steel together with a mounting rod such as a bolt, and a continuous underground wall in which a wall member having the connecting bracket is sequentially built in a solidified body such as soil cement. Concerning construction method.

  The underground continuous wall construction method is classified into the following two types depending on whether or not the wall members are rigidly connected to each other. In the first method, as disclosed in Patent Documents 1 and 2, a solidified body such as soil cement is formed along with the ground excavation along the wall construction portion, and the subsequent wall member is followed by a solidified body such as soil cement before solidification. The wall members are constructed while being connected to each other via joints. For example, as disclosed in Patent Document 3, the second method is the same as the first method in that a solidified body such as soil cement is formed along with the ground excavation along the wall construction part. Build in the improved body at a predetermined interval.

  The wall member used in the first method is referred to as “NS-BOX”. In this wall member, a plurality of H-section steels are integrated into a design length. At the same time, it has a male or female joint provided along the flange end of each H-section steel, and the adjacent H-sections are connected in the horizontal direction via the joint. For this reason, the built underground continuous wall has a double joint structure because each wall member is built with both sides of the H-shaped opposed flanges fitted through each other's joints. Excellent durability and water-stopping properties can be obtained because of the built-in relationship in the improved body.

  The wall member used in the second method is the same as the above-mentioned “NS-BOX” type wall member in that the H-section steels are connected to the design length. Does not have a joint. Therefore, in the constructed underground continuous wall, each wall member becomes an integrated body through the ground improvement body, and lacks both durability and water stoppage compared with the underground continuous wall constructed by the first method. Since construction costs can be significantly reduced, it is widely used. Further, in the second method, as disclosed in Patent Documents 3 and 4, for example, the upper H-section steel constituting each wall member built in order to reduce the total amount of steel materials and the construction cost is extracted and collected. The structure to perform is also known.

  More specifically, in Patent Document 3, for example, this connection structure is formed by, for example, an outer shell member that surrounds the outer periphery of the abutting portion in a state where the upper and lower H-section steels (core materials) are butted together, It has a joining means (temporary bolt) that joins the H-shaped steel, and a fracture bolt that joins the outer frame member and the other H-shaped steel, and applies a force greater than a predetermined tensile force to one of the H-shaped steels. The broken bolt breaks and separates the upper H-section steel. And as an underground wall construction method, the said wall member is built in a ground improvement body, and the construction of a wall member is interrupted before temporary bolts are buried in the ground. The temporary bolt is removed from the outer shell member, and the wall member is built again and embedded to a predetermined position. After the use as a wall member is finished, a tensile force is applied to the H-shaped steel above the butt portion to break the fracture bolt and pull out the upper H-shaped steel.

  In Patent Document 4, this connection structure has a joining plate arranged across both the upper and lower outer surfaces of the upper and lower ground portions and the cut-out portion side flange in a state in which the upper and lower H-sections are butted together. The upper and lower flanges and the joining plate are screwed together with bolts and nuts to connect the upper and lower H-section steels together. As an underground wall construction method, it builds in the ground improvement body (standing column continuous wall) formed in the ground in the state which connected the H-section steel of the upper and lower stages through the joining board and the volt | bolt. After that, with the excavation part side excavated, the bolt with the head part arranged on the cut part side flange is unscrewed from the nut provided on the ground mountain side flange via the joining plate, and the bolt is removed to the cut part side. The joint of the upper and lower H-sections is separated, and the upper H-section is pulled out. Then, the excavated part is backfilled with earth and sand.

Japanese Patent Application Laid-Open No. 2001-287738 JP 2003-55960 A JP 2004-238998 A Japanese Patent No. 3404315

  12 (a) and 12 (b) are constructed by maintaining the predetermined distance by the above-mentioned first method and excavating between the underground continuous walls 90 and constructing the underground structure 60 between the underground continuous walls 90. An example is shown. As shown in FIG. 8 and FIG. 9, which is an example of the present invention, this construction procedure is performed by constructing underground continuous walls on both sides, and then excavating between the underground continuous walls, and in the excavated portion, an underground structure 60 is built with the underground continuous wall as a temporary combined body wall. Thereafter, the upper part of the underground structure 60 is backfilled with earth and sand 65. In each continuous wall, the wall members 91 arranged adjacent to each other are connected to each other via a joint (a male joint of one wall member and a female joint of the other wall member), and the temporary combined body of the underground structure 60 Used as a wall. Reference numeral 92 denotes a solidified solidified body.

  In the above underground continuous wall 90, the earth pressure gradually decreases between the top plate 64 of the underground structure 60 and the ground surface GL, and therefore, strength and rigidity smaller than the point F are often sufficient, and if it is left buried, On the contrary, it may become an obstacle. In particular, in the case of underground structures that have long construction sections such as tunnels and joint grooves and are constructed at large depths, a considerable amount of steel is wasted depending on the construction section, and from the viewpoint of effective use of resources. Is not a good idea.

  As measures against this, the present applicants previously developed and filed an optimum underground continuous wall construction method that is friendly to the environment according to the ground conditions such as the original ground (Japanese Patent Application No. 2008-204907). Issue). This main part has a configuration in which at least the upper part of the wall member is made relatively small, and in this case as well, the adjacent members can be connected to each other via a joint. For this reason, in the prior application, the total amount of steel material used as the underground continuous wall can be reduced, but the upper H-section steel remains buried and still unsatisfactory as an obstacle countermeasure and effective utilization of materials. Therefore, as a further countermeasure, it is conceivable that the upper H-section steel of the wall member is detachably connected as in Patent Documents 3 and 4, and separated and recovered later.

  However, in the construction work, after the main construction is completed and backfilling is completed, the ground is compacted and the ground needs to be cured for at least several months to a year. Since steel is also expected to have support, recovery or removal work cannot be undertaken during the curing period. From such a situation, in the upper recovery structure of Patent Document 4, since the upper and lower H-section steels are butted together, the joining plates are simply arranged across the upper and lower outer surfaces of each other, When the bolt for connection through the joining plate is removed, there is a problem that the upper side becomes unconstrained with respect to the lower side and is easily displaced. On the other hand, in the upper recovery structure of Patent Document 3, since the outer frame member surrounds the outer periphery of the abutting portion in a state where the upper and lower H-shaped steels abut each other, each wall member is a mutual underground wall construction method. It is not possible to adopt the first method of connecting through a joint. Moreover, in the conventional structure, when the wall member becomes longer, you may want to connect it to the upper end of the lower H-section steel while it is being built in the state where the upper H-section steel is lifted. The H-shaped steel is easy to move, and it is difficult to position the upper mounting hole with respect to the lower H-shaped steel mounting hole. In addition, since these recovery works have been completed for a long time since the completion of the work, there is a possibility that they will be economically unprofitable. Such operations as re-digging and backfilling are not realistic.

  The present invention solves the above problems. The purpose of the wall member fitting to be built in the ground is, for example, after backfilling and compacting the excavated part on the top plate of the underground structure, and after a predetermined curing period, A connection fitting that can efficiently recover the upper part of the H-section steel located above the ground by a simple and small-scale work and a wall member having the same are used without impairing the construction work and the structure construction work. It is in providing the underground continuous wall construction method.

  The invention of claim 1 connects the upper and lower H-section steels constituting the wall member built in the ground in a separable manner, from the mounting hole provided in one flange of the H-section steel to the other. It is used with mounting rods such as bolts that are operated toward the mounting holes provided in the flange, and is arranged over the upper and lower ends where the upper and lower H-section steels are abutted with each other. A connecting metal fitting for connecting the H-shaped steels to each other, comprising a steel material having a size arranged in a recess defined by both flanges and webs of the H-shaped steel, and one of the upper and lower ends. An insertion portion disposed in the recess at the other end in a state of being fixed to the recess at the end, and both flanges provided in the insertion portion and defining the recess at the other end And an insertion hole through which a mounting bar that matches the mounting hole is passed. It is characterized in that. In addition to the commercially available bolts, the above-mentioned “bolt mounting rods” include, for example, steel mounting or connecting shafts or pin members between members (insertion holes and insertion parts of both flanges). Hole) is used in a meaning including a configuration in which it is arranged in a skewered manner and is provided with a retaining treatment.

  The invention of claim 2 is arranged in each of the recesses defined by both flanges and webs of the H-shaped steel constituting the one end portion, using two as a set in claim 1, Either fixing to each recess by welding or fixing each connection fitting via a common bolt using an insertion hole provided in the web and penetrating the recesses. It is characterized by that.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the insertion portion of the connection fitting is formed so as to be accommodated in the concave portion and disposed between the flanges of the concave portion with substantially no gap. It is characterized by that. On the other hand, the invention of claim 4 is characterized in that, in any one of claims 1 to 3, the insertion portion is formed by penetrating the insertion hole in the wall thickness direction.

  Invention of Claim 5 is the underground continuous wall construction method which builds in order in solidified bodies, such as soil cement which solidifies each wall member over time, As said wall member, in any one of Claim 1 to 4 Use the ones with connecting metal fittings, and each wall member is built continuously in the solidified body in such a manner that the head of the mounting bar is on the side of the cut-off part opposite to the natural ground side. A construction process for constructing a wall, a structure construction process for constructing an underground structure in the excavation part by excavating the excavation part side of the underground continuous wall together with a part of the solidified solidified body, and the underground structure After removing the mounting bar in the process of backfilling the cut-out portion on the object and completing the backfill, the upper recovery step of drawing out the upper H-shaped steel constituting each of the wall members is performed. It is characterized by.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, in the erection step, a temporary receiving plate is fixed to upper outer surfaces of both flanges of the lower H-shaped steel constituting the wall member, and the upper The lower H-section steel is not connected to each other, and the lower H-section steel is built in the solidified body before the solidification except for the upper part thereof, and the temporary H jig is installed on the ground surface side with respect to the temporary receiving jig. After being supported in a suspended state via a receiving plate, the upper H-section steel is abutted against the lower H-section steel and connected via the connection fitting and the mounting bar.

  According to a seventh aspect of the present invention, in the upper recovery process according to the fifth aspect, the upper H-section steel is penetrated from the ground surface side to the vicinity of the connection fitting by using a penetrating rod means having a rotating boring rod. The solidified material adhering to the surface is scraped off, and / or fluidized soil is injected and filled into the gap formed when the upper H-shaped steel is pulled out. This fluidized soil has various strength promoters (for example, promoters that can be solidified in a few hours after filling the ground clearance) in the fluidized soil to effectively prevent the possibility of ground collapse due to the upper recovery process. Including the included configuration.

  The invention according to claim 1 is the same as Patent Documents 3 to 4 in that the upper and lower H-sections can be separated from each other by the operation of removing the mounting bar as the wall member connection fitting. In addition, the connecting bracket of the present invention is smaller in size than the prior art because it is arranged in the concave section defined by both flanges and webs of H-shaped steel, and it is easy to position relative to the concave section, and has excellent handling properties. At the same time, regardless of the small size, the upper and lower H-section steels are excellent in restraining property with the mounting bar removed. In other words, the connection fitting of the present invention has an insertion portion of the connection fitting as a mating recess as compared to the structure in which the joining plates are arranged across the upper and lower outer surfaces of the flanges of the H-shaped steels as in Patent Document 4. Because it is inserted, it is easy to match the holes, good operability and pulling out are realized, and even in the state where the upper and lower H-shaped steels have pulled out the mounting bar, the fitting force between the insertion part and the recess is It is excellent in maintaining the rigidity as a proportional monolith. Compared to the structure in which the outer frame member and the connecting member are broken as in Patent Document 3, there is no inadvertent breakage and excellent safety and reliability. Applicable to structures

  In the invention of claim 2, as inferred from FIGS. 1 to 5, in a state where the two connection fittings are fixed to the respective concave portions forming the lower or upper H-shaped steel, For steel, the H-shaped steel web is fitted into the gap between the insertion parts of each connection fitting and the positioning when fitting the insertion part of each connection fitting into each recess of the H-shaped steel. Due to the synergistic effect with the positioning at the time, the flange-side mounting hole of the H-shaped steel and the insertion-portion-side insertion hole of the connection fitting are positioned reliably and with high accuracy. In addition, the structure in which each connecting bracket is fixed to the corresponding recess by welding or the structure in which each connecting bracket is fixed to the corresponding recess through a common bolt is H-shaped as compared to conventional bolt fixing. Protrusions caused by bolt heads and the like can be eliminated on the outer surface of the flange, particularly on the outer surface of the flange on the excavation side. For example, this specification is suitable for the case where the side wall of the underground structure is combined and integrated with the outer surface of the flange on the excavation side if the specification is to construct the underground structure in a later process.

  In the invention of claim 3, the upper and lower H-sections are in a state in which the corresponding portion of the connection fitting is fixed to the recess at one end, and the presence of the insertion portion inserted into the recess at the other end almost without a gap. Even when the mounting bar that fixes the insertion portion and the other end portion is removed, the rigidity as an integral component proportional to the fitting force between the insertion portion and the recess of the connection fitting can be reliably maintained.

  In the invention of claim 4, since the insertion part of the connection fitting penetrates the insertion hole for bolts in the wall thickness direction (the inside of the plate-like thickness is formed in a hole shape), the above protection The load applied to the mounting bar can be dispersed without requiring a material, and the sticking operability of the bar can be maintained satisfactorily by reducing the deposits on the bar.

  In invention of Claim 5, as a underground continuous wall construction method which builds each wall member in a solidified body, the wall member which has the connection metal fitting in any one of Claim 1 to 4 as a wall member compared with the past After building the underground structure, remove the mounting bar in the process of backfilling the excavated part on the underground structure, and after completing the backfilling, pull out the upper H-section steel of each wall member The point is different. And in the underground continuous wall construction method of the present invention, after completion of backfilling and compaction and curing as described in the problem, the H-section steel at the upper stage of each wall member is sequentially pulled out for diversion, or steel material It is excellent as a resource saving and obstacle removal configuration.

  In the invention of claim 6, for example, in a state where the temporary receiving plate is fixed to the lower H-shaped steel side, the lower H-shaped steel is built in the solidified body except for the upper portion thereof, and the temporary receiving on the ground surface side is provided. Since the upper H-shaped steel is abutted against the jig through the provisional receiving plate and connected via the connection fitting and the mounting bar, the upper H Positioning can be easily performed while moving the section steel relative to the lower H section steel in the middle of the construction, thereby improving the connection workability.

  In the invention of claim 7, in the upper recovery step, the H-shaped steel is solidified by penetrating from the ground surface side to the vicinity of the connecting metal by the penetrating rod means and scraping off the solidified material adhering to the upper H-shaped steel. The power required for extraction can be reduced by cutting the edges. Further, the fluidized soil is injected and filled into the gap formed by the drawing of the upper H-section steel by the penetrating rod means, so that the problems associated with the drawing can be easily solved.

It is a perspective view which shows the wall member and connecting metal fitting of a 1st form in the separation state of the upper stage H-section steel. (A) is the perspective view which shows the said wall member in the connection state of the upper stage H-section steel, (b) is a sectional side view corresponding to the AA line of (a), (c) is a modification of (b) It is a block diagram shown with the cross section corresponding to the A1-A1 line. It is a perspective view which shows the wall member and connecting metal fitting of a 2nd form in the state which isolate | separated the upper stage H-section steel, and was partly fractured. (A) is the perspective view which shows the said wall member in the connection state of the upper stage H-section steel, (b) is a sectional side view corresponding to the A2-A2 line of (a), (c) is a modification of (b) It is a block diagram shown with the cross section corresponding to the A3-A3 line. (A) And (b) is a perspective view which shows the wall member and connection metal fitting of a 3rd form in the division | segmentation state of upper stage H-section steel, and the connection state of upper stage H-section steel. (A) And (b) is a perspective view for explanation which shows the composition when connecting the upper stage H section steel to the lower stage H section steel in the middle of construction using the wall member of the first form in the state before connection and after connection. It is. (A) And (b) is a perspective view for explanation which shows the composition when connecting an upper stage H section steel to a lower stage H section steel in the middle of building using the wall member of the 3rd form in the state before connection and after connection. It is. (A), (b) is sectional explanatory drawing which shows the creation completion state which built the said wall member, and a cutting process. (A), (b) is sectional explanatory drawing which shows the completion state of a permanent underground structure, and a backfilling process. (A), (b) is a schematic diagram which shows the suspension operation | work performed at an upper collection | recovery process, and a schematic diagram which shows drawing | extracting and a gap | interval or cavity filling operation | work. It is sectional explanatory drawing which shows the completed state of the underground structure built and the underground continuous wall made by the method of this invention. It is a figure for demonstrating a prior art example, (a) shows the state which built the underground structure between underground underground walls, (b) is the DD sectional view taken on the line of (a).

  In the following, after explaining the first embodiment shown in FIG. 1 and FIG. 2, the second embodiment shown in FIG. 3 and FIG. 4, and the third embodiment shown in FIG. -The underground continuous wall construction method shown in FIG. 11, the underground continuous wall, and its use example as an installation and use main body wall are mentioned.

(First Mode) In FIGS. 1 and 2, the wall member 1 of the first mode is joined from the bottom to the top of the H-section steel 2 as the root portion and the upper end of the H-section steel 2. The lower H-shaped steel 3 integrated with the upper H-shaped steel 3 is connected to the upper end of the H-shaped steel 3 in a separable manner via a connection fitting 6, a bolt B as a mounting bar, and a mounting plate 7. It is composed of steel 4. In addition, this bolt B is a long bolt according to the space | interval of the flanges of H-section steel, and multiple pieces are used.

  Here, the lower H-section steel 3 and the upper H-section steel 4 have the same cross-sectional shape as “NS-BOX”. In the H-shaped steel 3 and the H-shaped steel 4, the H-shaped web 3b and the web 4b having the same shape, and the H-shaped flanges 3a and 3a and the flanges 4a and 4 having the same shape are abutted at the upper and lower ends. And the H-section steel 3 and the H-section steel 4 are the connection fitting 6 of this invention arrange | positioned over the upper-lower-ends part, and the flange 4a of the H-section steel (in this form, the flange of the H-section steel 4 of the upper stage) 4a) is connected via a bolt B which is a mounting rod operated from the mounting hole 10 provided in 4a) to the mounting hole 10 provided in the other flange 4a, and each H-shaped steel 3, 4 Although it has the female joint 5 provided along each edge part of the flanges 3a and 4a and abbreviate | omitting illustration, the H-shaped steel arrange | positioned adjacent is the said female joint 5 and the other party male joint It is connected via. The mounting holes 10 are holes through which the bolts B can be inserted, and are provided in a number corresponding to the bolts B. In this embodiment, the mounting hole 10 is a simple hole, but may have a female screw configuration corresponding to the bolt B.

  The number of the H-section steels 3 in the lower stage is one on the drawing, but in actuality, the number of H-section steels is joined and integrated according to the design length. The upper H-section steel 4 has a plurality of hanging attachment holes 12 provided in the upper part of both side flanges 4a. This mounting hole 12 is a hole for connecting to a lifting jig as in the prior art. The mounting holes 12 can be connected to the lower stage side even if the upper H-section steel 4 is upside down by setting the same number and the same positions as the mounting holes 10 for the bolts B. Can improve. On the other hand, the lowest H-section steel 2 has a smaller cross-section than the H-section steels 3 and 4 and is built in, for example, a water-impermeable layer in a deep underground part or a place where water stoppage in the ground is unnecessary. That is, the H-section steel 2 has a web 2b joined to the web 3b of the H-section steel 3 and the H-shaped flanges 3a and 3a, as compared with the section of the H-section steel 3 whose cross section intersects the longitudinal direction. It is a shape having short flanges 2a, 2a joined to a part. Of course, the lowermost H-section steel 2 can be omitted.

  The connection fitting 6 preferably has the following requirements (1) to (4). (1) The connection fitting has a length (preferably 100 mm or more) dimension that is arranged over the upper and lower ends of the upper and lower H-section steels 3 and 4. (2) As shown in FIGS. 1 to 4, the connection fitting is formed by the recesses 3 c and 3 c (sections) defined by the flanges 3 a and 3 a (4 a and 4 a) and the web 3 b (4 b) of the H-shaped steel 3 (or 4). 4c, 4c) is a steel material having a size capable of maintaining good restraint between the upper and lower H-section steels. (3) The protrusion is arranged in the concave portion 4c or 3c at the other end in a state of being fixed to the concave portion 3c or 4c at one end of the upper and lower ends of the H-shaped steels 3 and 4 at the upper and lower stages. It has the insertion part 6a which is a part. This insertion part 6a is accommodated in the said recessed part, and is arrange | positioned without a clearance gap between both flanges of this recessed part. (4) The connection fitting has an insertion hole 8 which is provided in the insertion portion 6a and coincides with the mounting hole 10 of both flanges defining the concave portion at the other end. Here, the connection fitting 6 is welded to the recess 3c at the upper end of the lower H-section steel 3 or the recess 4c at the lower end of the upper H-section steel 4 as illustrated in FIG. Fixed. As a fixing structure other than this welding, as illustrated in the modification of FIG. 2 (c), a web 3b at the upper end of the lower H-section steel 3 or a web 4b at the lower end of the upper H-section steel 4 is used. On the other hand, a plurality of insertion holes penetrating through the recesses and a plurality of insertion holes penetrating through corresponding portions of the connection fittings 6 arranged in the respective recesses 3c or the respective recesses 4c are formed in the respective insertion holes. The structure fixed through the common volt | bolt B and nut N which are penetrated may be sufficient. In these structures, as compared with the conventional bolt fixing structure, it is possible to eliminate protrusions caused by bolt heads and the like on the outer surface of the flange on the excavation side that constitutes the H-shaped steel.

  More specifically, the connection fitting 6 described above includes a main body wall a having a cross section arranged along the webs 3b and 4b as shown in the enlarged view of FIG. 1 and both side walls b standing on both sides of the main body wall a. And an upper reinforcing wall c and a lower reinforcing wall d which are connected to the side of the both side walls b away from the main body wall a. For this reason, the insertion part 6a of the connection metal fitting 6 is comprised by the upper part and the upper reinforcement wall c which comprise the main body wall a and the both-side wall b, or the lower side of the main body wall a and the both-side wall b It consists of a part and a lower reinforcing wall d. The insertion part 6 is provided with an insertion hole 8 through which a mounting bar such as a pair of bolts passes, on the same axis with respect to both side walls b.

  Moreover, the insertion part 6a has the protective material 9 which both ends were joined and fixed to the inner surface of the both-side wall b which comprises the insertion part 6a, and connected each insertion hole 8 by the cylinder part. This protective material 9 disperses the load received from the ground side by inserting the shaft portion of the mounting bar such as bolt B into the cylinder, and reduces the amount of deposits on the mounting bar to remove the bar. To maintain good operability. Further, the mounting plate 7 has a hole or a female screw coaxial with the nut N. For example, if the connection fitting 6 is fixed to the lower H-section steel 3 as shown in FIGS. The flange 3a is fixed to the outer surface on the upper end side. On the other hand, when the connection plate 6 is configured to be fixed to the upper H-section steel 4, the attachment plate 7 is fixed to the outer surface on the lower end side of the flange 4 a of the H-section steel 4. The nut N is preferably, for example, a cap nut that covers the screwed portion in order to avoid a matter that is attached to the screwed portion in the tightened state of the bolt B, and that the bolt B is less likely to come off.

(Second Mode) In FIGS. 3 and 4, the wall member 1A of the second mode is such that the lower H-section steel 3A and the upper H-section steel 4A have the same shape and have a joint as in the first mode. It is the same steel composition as patent documents 3 and 4 which are not. Further, the lower H-section steel 3 and the upper H-section steel 4 are formed by connecting the web 3b and the web 4b, the flanges 3a and 3a and the flanges 4a and 4a at the upper and lower ends, and the connection fitting 6A of the present invention. , And a bolt B operated from the mounting hole 10 provided in one flange 3a of the H-shaped steel (in this embodiment, the flange 3a of the lower H-shaped steel 3) toward the mounting hole 10 provided in the other flange 3a, etc. Are connected via a mounting bar. Each of the wall members 1A described above is a type that is not rigidly connected because adjacent H-shaped steels do not have a joint. The attachment hole 10 is the same as in the first embodiment.

  The connection fitting 6A has the requirements (1) to (4) described in the first embodiment. In addition, the connection fitting 6A has a simple thick plate shape as shown in FIG. 1 with a part thereof broken, and an insertion hole 8a is formed through the insertion portion 6a in the plate width direction. Therefore, in the 2nd form, since the insertion part 6a of 6 A of connection metal fittings has formed the penetration hole 8a in thickness, the protective material 9 like a 1st form is not required. Further, a plurality of nuts N are fixed to the outer surface of the other flange 3a by welding or the like on the coaxial line with the mounting hole 10 according to the number of bolts B used. However, the nut N may be welded and fixed to the other flange as described above while being mounted on the mounting plate 7 of the first form. Furthermore, structurally, in addition to the configuration in which the bolt B is screwed into the nut N as in this example, any of the configuration in which the internal thread formed in the mounting hole 10 and the nut N are tightened, and the configuration in which the internal thread formed in the mounting hole 10 is tightened. But you can. Further, as illustrated in FIG. 4B, the connection fitting 6 described above is fixed to the recess 4 c at the lower end of the upper H-section steel 4 or the recess 3 c at the upper end of the lower H-section steel 3 by welding. Is done. As a fixing structure other than this welding, as illustrated in the modified example of FIG. 4C, the lower end web 4b of the upper H-section steel 4 or the upper end web 3b of the lower H-section steel 3 is used. On the other hand, a plurality of insertion holes penetrating through the recesses and a plurality of insertion holes penetrating through the corresponding recesses 4c or corresponding portions of the connection fittings 6 arranged in the recesses 4c are formed in the respective insertion holes. The structure fixed through the common volt | bolt B and nut N which are penetrated may be sufficient. In these structures, as compared with the conventional bolt fixing structure, it is possible to eliminate protrusions caused by bolt heads and the like on the outer surface of the flange on the excavation side that constitutes the H-shaped steel. These are the same as in the first embodiment.

(3rd form) In FIG. 5, the wall member 1B of the 3rd form is the lowest H-section steel as a penetration part from the bottom to the top similarly to what is described in Japanese Patent Application No. 2008-204907. 2, the lower H-section steel 3 joined and integrated with the upper end of the H-section steel 2, and the connection fitting 6 of the present invention at the upper end of the H-section steel 3 and formed in substantially the same shape as the H-section steel 2. It is comprised with the H-section steel 4 of the upper stage connected so that isolation | separation is possible via the bar for attachments, such as volt | bolt B. FIG.

  Here, the lowest H-section steel 2 and the lower H-section steel 3 are the same as in the first embodiment. The upper H-section steel 11 is similar to the H-section steel 2 in that the cross-section intersecting the longitudinal direction of the H-section steel 11 is lower than that of the lower H-section steel 3, and the web 11b joined to the web 3b of the H-section steel 3; It has a shape having short flanges 11a and 11a joined to a part of the shape flanges 3a and 3a, and is built in, for example, a place where water stoppage is unnecessary in the ground. Further, the H-shaped steel 3 and the H-shaped steel 11 include the connection fitting 6B of the present invention disposed over the upper and lower end portions thereof, and one flange of the H-shaped steel (in this embodiment, the flange 3a of the lower H-shaped steel 3). ) To the mounting hole 10 provided on the other flange 3a from the mounting hole 10 provided on the other flange 3a. The mounting hole 10, bolt B, and nut N are the same as in the second embodiment. The nut N may be fixed to the corresponding flange (3a or 11a) of the H-section steel 3 or the H-section steel 11 as a single unit through the mounting plate 7 as in the first embodiment.

  The connection fitting 6B has the requirements (1) to (4) of the first form described above. In addition, as compared with the first embodiment, the connection fitting 6B includes a main body wall having a cross section disposed along the webs 3b and 11b, both side walls standing on both sides of the main body wall, and the main body wall. The upper connecting piece (or the lower connecting piece) connecting the both side walls in a state of being arranged substantially in parallel with the inner wall and the inner lower end (or inner upper end) of the main body wall. A lower connecting piece (or an upper connecting piece) that connects both side walls is integrally formed. For this reason, the insertion part 6a of the connection fitting 6B is comprised by the lower part and the lower connection piece of the said main body wall and both side walls like FIG. 5, or has comprised the said main body wall and both side walls. It consists of an upper part and an upper connecting piece. The insertion portion 6 is provided with a pair of insertion holes 8a coaxially with respect to the side walls.

(Underground Continuous Wall Construction Method) FIGS. 6 to 10 show the underground continuous wall 50 constructed by the building process, the structure building process, and the upper part of the underground continuous wall construction method corresponding to claim 5. The details of the recovery process are shown. Here, as an underground continuous wall construction method, when each wall member 1 (or 1B) is sequentially built in a solidified body such as soil cement that solidifies with time, the subsequent wall member 1 (or 1B) is followed by An example of a configuration in which the wall member 1 (or 1B) is connected to each other via a joint (a female joint and a male joint) 5 will be described. However, the target underground continuous wall construction method may be configured such that each wall member 1A is constructed at a predetermined interval when it is built in order in a solidified body such as soil cement that solidifies over time. When the wall member 1B is used, it is built by the underground continuous wall construction method described in Japanese Patent Application No. 2008-204907, and the upper H-section steel 11 is removed by the upper recovery step of the present invention. Will be.

  In other words, in the underground continuous wall construction method, on the premise that the above-described wall member 1 (1A or 1B) is used, each wall member is sequentially built in the solidified body before solidification, and the underground continuous wall 50 is formed. A construction process for constructing, a structure construction process for constructing an underground structure 60 in the excavated part by excavating the part of the underground continuous wall 50 along with the part of the solidified body 51, and an underground structure An upper recovery step of removing the bolt B, which is a mounting rod, in the process of backfilling the cut-out portion on the top 60, and pulling out the upper H-section steel 4 constituting each wall member 1 after completing the backfill; Go through.

  The following is important in the building process. When the wall member 1 or 1B is used, the wall member 1 or 1B is connected to the preceding wall member 1 or 1B while being connected to each other via the joint 5 (female joint and male joint). When the member 1A is used, in the operation of building at a predetermined interval, each wall member 1 is arranged so that the head of the bolt B that is a mounting bar is on the side of the cut portion opposite to the natural ground side. Further, when the wall members 1, 1A, 1B are considerably longer than usual, they are connected to the upper ends of the lower-stage H-section steels 3, 3A, 3 in the middle of the construction while the upper-stage H-section steels 4, 4A, 11 are lifted. Sometimes. 6 and 7 show the connection procedure in that case. FIG. 6 shows an example in which the wall member 1 and the connection fitting 6 of the first form are used, and the connection fitting 6 is built in a state where it is fixed to the lower H-shaped steel 3 side. In this example, the mounting plate 7 is omitted, and the nut N and the mounting hole 10 are provided on the upper H-section steel 4 side. On the other hand, FIG. 7 shows an example in which the wall member 1B and the connection fitting 6B of the third form are used, and the connection fitting 6B is built in a state of being fixed to the upper H-shaped steel 11 side.

  6 and 7, each main part fixes a pair of provisional receiving plates 23 to the upper outer surfaces of both flanges 3 a of the lower H-section steel 3. Thereafter, the lower H-section steel 3 is built in the solidified body 51 before solidification except for the upper portion thereof, and is suspended from the temporary receiving jigs 28 installed on the ground surface via the temporary receiving plates 23. Support the state. From that state, the upper H-section steel 4 in FIG. 6 (b) or the upper H-section steel 11 in FIG. 7 (b) is brought into contact with the upper end of the lower H-section steel 3 so that the connection fitting 6 or 6B, And a plurality of bolts B.

  First, at the time of erection, a groove having a predetermined width and depth is excavated by a cutter device. In this operation, for example, the ground is excavated while the cutter device is moved from the excavation start position along the planned wall construction portion while injecting the drilling liquid into the excavation groove 26 to soften the ground, and the design depth and When the construction length is reached, cement milk or the like is supplied as the solidified body 51, and the groove is filled with soil cement or the like. In addition, prior to the erection operation, a plurality of temporary receiving plates 23 are welded to each lower H-section steel 3 on the upper end outer surface of both side flanges 3a.

  In the erection operation, for example, at the stage of suspending the wall member 3 by a construction heavy machine (not shown), it is crossed over the upper ground surface of the excavation groove 26 defined by the pair of guide trenches 24 and is combined with the H-shaped steel. A well-shaped temporary receiving jig 28 is installed. Specifically, as shown in FIG. 6A, before and after the wall member 3 in the middle of the construction, two steel members 28a such as H-shaped steels hung on the guide wrench 24 on both sides and both sides of the wall member 3 The temporary receiving jig 28 is made with the two steel materials 28b stretched over each steel material 28a. When the lower H-section steel 3 is further suspended, the temporary receiving plate 22 is placed on the temporary receiving jig 28, and the entire load is deposited on the temporary receiving jig 28.

  After that, as shown in FIG. 6B and FIG. 7B, the upper H-section steels 4 and 11 are suspended and positioned with respect to the lower H-section steel 3 via the connection fitting 6 or 6B. Then, the bolts B are connected by the tightening operation. As shown in FIG. 6, the operation procedure is as follows. A pair of fittings 6 is fixed to each recess 3c of the lower H-section steel 3, and each insertion portion 6a protruding upward from each recess 3c is connected to the upper H-section steel. In the state of being fitted in the corresponding concave portion 4c, the upper flange side and the lower flange side are finely moved, while the mounting hole 10 on the one flange 4a side, the bolt insertion hole 8 on the insertion portion 6a, and the other flange 4a. Match the nut N. In the case of FIG. 7, the pair of connection fittings 6 are fixed to the respective concave portions 11 c of the upper stage H-shaped steel 11, and the respective insertion portions 6 a protruding downward from the respective concave portions 11 c are used as the corresponding concave portions of the lower stage H-shaped steel 3. While fitting in 3c, while finely moving both the upper stage side and the lower stage side, the mounting hole 10 on the one flange 3a side, the bolt insertion hole 8 of the insertion portion 6a, and the nut N of the other flange 4a Match. That is, in this configuration, in any aspect, each insertion portion 6a is fitted into the counterpart recess, the counterpart web 4b or 3b is fitted between the insertion portions 6a, and the upper stage side. In addition, since the positioning can be performed while finely moving both the lower side and the bottom side, the scaffolding is bad, and even with a long H-shaped steel, a plurality of holes can be positioned easily and reliably.

  After connecting the upper and lower H-shaped steels 3 and 4 or the H-shaped steels 3 and 11 with the bolt B described above, when the temporary receiving plate 23 is intentionally removed (the temporary receiving plate 23 is not removed, the wall May be left as a reinforcing member for the member), and the temporary receiving plate 22 is melted in a state where the wall member 1 or 1B is lifted and floated from the temporary receiving jig 28. Further, after removing the temporary receiving jig 28 in the meantime, each wall member is continuously suspended, and the vertical degree is accurately maintained via the joints, and only the upper end is left in the excavation groove 26. It will be.

  Fig.8 (a) has shown typically the underground continuous wall 50 constructed | assembled by the above erection process. In this example, the wall member 1 of the first form is used, and the underground continuous wall 50 is provided in two rows with a width corresponding to the underground structure. In the continuous wall 50 in each place, the upper H-section steel 4 constituting each wall member 1 protrudes slightly from the ground surface GL. This is to make it easier to pull out the H-section steel 4 in the upper recovery step as will be described later. Each wall member 1 is embedded in a solidified body 51 solidified together with the connection fitting 6 except for the upper end as shown in the enlarged view of FIG.

  In the structure building process, the space between the underground continuous wall 50 and the underground continuous wall 50 is excavated together with a part of the solidified body 51, and the underground structure 60 is constructed at the excavated portion by the same procedure as before. That is, in this work, the ground between the underground continuous walls 50 is excavated from the ground surface to a predetermined depth as shown in FIG. In this case, the open-cut design is made slightly higher than the lower end portion of the lower H-section steel 3 of each wall member 1 (including the configuration composed of a plurality of H-section steels) according to the plan, and this portion is an underground structure. It is set as the support ground surface of the thing 60. Moreover, solidified bodies 51, such as soil cement, adhere to the inner flanges of the H-section steels 3 and 4 constituting the wall member 1 among the opposing surfaces of the underground continuous walls 50, but these adhered substances Is removed.

  In the excavation work, as the excavation depth becomes deeper, the temporary support work 52 made of a cut beam or the like is stretched on the upper side between the underground continuous walls 50 as necessary. By the way, the distribution of the earth pressure P due to the excavation is maximized in the vicinity of the intermediate position in the height direction of each wall member 1, but in the wall structure of the underground continuous wall 50, The earth pressure P can be sufficiently resisted by the rigidity of the H-shaped steel 3 and the solidified body 51 on the outside thereof. Moreover, even if there is groundwater in the ground E, if the position of the lower H-section steel 3 is set higher than the groundwater level by a preliminary survey or the like, the inner and outer double joint structure and the outer solidified body 51 The water-stopping property is also satisfactory.

  After completion of the excavation work, as shown in FIG. 9A, the bottom plate 61, the side wall 62, the partition wall 63, and the top plate 64 of the underground structure 60 are appropriately disposed on the supporting ground along the construction direction of the underground continuous wall 50. Built by the formwork method. At that time, concrete is placed as necessary in a state where both sides of the bottom plate 61, both side walls 62 and both sides of the top plate 64, and corresponding portions of the wall member 1 are joined via a reinforcing bar or the like. As a result, the underground structure 60 is integrated and integrated with the lower H-section steel 3 in which both side walls 62 constitute each wall member 1, and the underground continuous wall 50 and the wall are formed even if the side wall 62 is a thin wall. The solidified body 51 on the outer side of the member provides a structure excellent in sufficient rigidity and water stoppage.

  In the upper recovery step, after the construction of the underground structure 60 is completed, the upper surface of the top plate 64 is backfilled with the backfilling earth and sand 65 while replacing the temporary support work 52. In this backfilling process, the bolt B used for the wall member 1 is removed. In this case, as shown in the enlarged view of FIG. 9B, when the connection fitting 6 is removed, the lower H-section steel 3 and the upper H-section steel 4 are separated from each other. The supporting force of the upper and lower H-shaped steels 3 and 4 is due to the holding force as an integral part proportional to the fitting force between the insertion part 6a of the connection fitting and the recessed part 4c or 3c, and the earth pressure of the earth and sand 65 for backfilling. Maintains independence against the earth pressure of the surrounding ground E. And the underground structure 60 will be completely embed | buried as shown in FIG.9 (b) by repeating backfilling and laying down to the surface part GL.

  The backfilled ground is compacted with heavy machinery. Thereafter, the earth and sand for backfilling 65 is cured for at least several months to one year as a guide, and consolidation is achieved. After confirming the consolidation of the internal ground, as shown in FIGS. 10 and 11, the upper H-section steel 4 constituting each wall member 1 is pulled out using a recovery jig device (not shown). Work is done. In the work, first, the penetrating rod means 71 is used to scrape off the solidified body 51 and the like adhering to the upper H-section steel 4 while penetrating from the ground surface side to the vicinity of the connection fitting 6 (hereinafter referred to as “suspending”). Say work).

  That is, the penetrating rod means 71 includes a rotating boring rod 72 having a tip formed in an inclined portion as shown in FIG. 10, and tap water and fluidized soil production plant as a water supply unit provided on the upper portion of the boring rod 72. 74 and a swivel 73 connected to each other via a hose or the like, and a water discharge portion 72a and a fluidized soil discharge portion (mekura lid) provided on the tip side as shown in the enlarged left side of FIG. And a double tubular supply passage that is provided in the boring rod 72 and communicates with each of the introduction portions of the swivel 73 and each of the discharge portions 72a and 72b.

  The above penetrating rod means 71 is used while being held by the heavy work machine 70. The heavy work machine 70 is commonly used as a backhoe and the like. The drive unit is replaced with a telescopic arm, and a boring rod 72 constituting a penetrating rod means 71 is rotatably mounted and held on the arm. The And it carries out in the state which stopped the pump P at the time of a fishing work. The procedure is carried out, for example, by extending the boring rod 72 while extending the arm of the heavy machinery 70 and penetrating tap water from the discharge part 72a. As shown in the upper schematic view of FIG. 10 (a), this work location is the outer side of the natural mountain side flange 4a and both sides of the web 4b, that is, the above-described recess 4c. When this operation is performed to a predetermined depth (near the connection fitting 6), the H-section steel 4 can be pulled out.

  Thereafter, the water supply is stopped, the boring rod 72 is once pulled up to the ground surface, the above-mentioned meckle lid is removed, and then inserted again into the suspended cavity. During the filling operation, when the pump P of the fluidized soil production plant 74 is driven, the fluidized soil is discharged from the discharge portion 72b through the swivel 73 and the center side supply passage. In this filling operation, the H-section steel 4 is pulled out by a collecting jig device (not shown) (hanging metal fittings, lifting wires, etc.). In this drawing operation, the above-described filling operation is performed, and the fluidized soil is discharged from the discharge portion 72b of the boring rod 72 to fill the gap or cavity after the drawing. By performing this filling operation in conjunction with the pulling speed of the H-section steel 4, it is possible to prevent ground subsidence or overflow of fluidized soil from the ground surface.

  Thereafter, the H-section steel 4 is sequentially pulled out by repeating the same operation. The collected H-section steel 4 is diverted to other construction or is effectively used as a steel material. In particular, when the underground structure is a structure such as a tunnel or a common ditch, the amount of steel recovered is enormous, and resource saving can be achieved. FIG. 11 schematically shows the underground structure 60 and the underground continuous walls 50 provided on both sides of the underground structure 50 constructed as described above. In the underground continuous wall 50, the wall members 1 are rigidly joined to each other via the joints 5, and the upper H-section steel 4 is removed. In this example, the connection fitting 6 protrudes from the upper end of the lower stage side H-section steel 3.

  As described above, the present invention only has to substantially include the configuration specified in each claim, and details can be changed with reference to the description of the embodiments. As an example, in the construction design, there is a specification in which the upper H-section steel is shorter than usual. In such a specification, the connection force between the insertion portion of the connection fitting according to the present invention and the concave portion of the other end portion of the upper and lower H-section steel is not so strong. Sometimes it may be. For this reason, as the “mounting rods such as bolts” of the present invention, connecting rods such as round steel and square steel or mounting rods, that is, those similar to bolts, are used, and the insertion portion is formed in the recess at the other end. The arrangement includes inserting or press-fitting into the mounting hole on the one flange side, the insertion hole on the insertion portion, and the mounting hole on the other flange side that define the recess. In that case, the head of the bar may be temporarily welded from the excavation side as necessary.

1, 1A, 1B: Wall member 3, 3A: Lower H-section steel (3a is flange, 3b is web, 3c is concave)
4, 4A ... Upper H-section steel (4a is flange, 4b is web, 4c is concave)
11 ... Upper H-section steel (11a is flange, 11b is web, 11c is concave)
6, 6B ... Connection fitting (6a is an insertion part, 8 is an insertion hole, 9 is a protective material)
6A: Connection fitting (6a is an insertion part, 8a is an insertion hole)
DESCRIPTION OF SYMBOLS 10, 12 ... Mounting hole 23 ... Temporary receiving plate 28 ... Temporary receiving jig 50 ... Underground continuous wall 51 ... Solidified body 52 ... Temporary support 60 ... Underground structure (62 is side plate, 64 is top plate)
71 ... Penetration rod means (72 is a boring rod, 73 is a swivel)
B ... Bolt (bar for mounting)

Claims (7)

The upper and lower H-section steels constituting the wall member built in the ground are connected to each other in a separable manner, and the attachment holes provided in the other flange from the attachment holes provided in one flange of the H-section steel It is used with mounting rods such as bolts that are operated toward the upper and lower ends of the upper and lower H-shaped steels, and the H-shaped steels are connected to each other via the mounting bar. A connecting bracket for connecting
It consists of the steel material of the magnitude | size arrange | positioned at the recessed part divided with both the flanges and webs of the said H-section steel, The said other end part is the state fixed to the said recessed part of one end part among the said upper-lower end parts. An insertion hole that passes through an insertion bar disposed in the recess and an attachment bar that matches the mounting hole provided in both flanges provided in the insertion part and defining the recess at the other end. And a wall member connecting metal fitting.   Two are used as a set, and are arranged in each recess defined by both flanges and webs of the H-section steel constituting the one end, and fixed to each recess by welding, 2. The wall according to claim 1, wherein each of the connection fittings is fixed through a common bolt using an insertion hole provided in the web and penetrating through the recesses. Connection bracket for members.   3. The wall according to claim 1, wherein, of the connection fitting, the insertion portion is formed so as to be accommodated in the recess and to be disposed between the flanges of the recess with almost no gap. Connection bracket for members.   The wall member connecting bracket according to any one of claims 1 to 3, wherein the insertion portion is formed by penetrating the insertion hole in a wall thickness direction. In the underground continuous wall construction method of building in order in a solidified body such as soil cement that solidifies each wall member over time,
Using the wall member having the connection fitting according to any one of claims 1 to 4,
An erection step of constructing an underground continuous wall by building each wall member in turn in the solidified body in such a manner that the head of the mounting bar is on the cut-off portion side opposite to the natural mountain side,
A structure building process in which the excavation part side of the underground continuous wall is excavated together with a part of the solidified solidified body and an underground structure is built in the excavation part;
An upper recovery step of removing the mounting bar in the process of backfilling the excavated portion on the underground structure, and extracting the upper H-shaped steel constituting each of the wall members after completing the backfilling; The underground continuous wall construction method characterized by passing through.   In the erection step, the temporary receiving plates are respectively fixed to the upper outer surfaces of both flanges of the lower H-shaped steel constituting the wall member, and the upper and lower H-shaped steels are not connected to each other. After the lower H-section steel is built in the solidified body before the solidification except for the upper part thereof, and supported in a suspended state via the temporary receiving plate with respect to the temporary receiving jig installed on the ground surface side 6. The underground continuous wall construction method according to claim 5, wherein the upper H-section steel is butted against the lower H-section steel and is connected via the connection fitting and the mounting bar.   In the upper recovery step, by using a penetrating rod means having a rotating boring rod, the solidified body penetrating from the ground surface side to the vicinity of the connection fitting and adhering to the upper H-section steel is scraped off, or 6. The underground continuous wall construction method according to claim 5, wherein fluidized soil is injected and filled into a gap formed as the upper H-shaped steel is pulled out.

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