JP4074241B2 - How to build steel - Google Patents

Description

The present invention has been made about the construction inclusive how steel for Tatekomu steel for forming such earth retaining walls and water shield wall in the ground, steel sheet pile, etc. in combination with for example shaped steel, Kenkomi Suitable for the construction of steel materials with a large excavation cross section for.

  A steel material having a large cross-sectional performance by combining a steel material having a H-shaped steel and a joint, such as a steel sheet pile, is actively used in Europe. The design of the earth retaining steel material allows the selection of the most suitable cross section for the necessary conditions because the cross section performance can be obtained with a wide variety of variations by appropriately selecting the size of the H-section steel as the main member of the cross section. There are advantages.

  However, there is a fact that this kind of earth retaining steel is rarely used in Japan. In other words, this kind of earth retaining steel is constructed with hydraulic hammers and vibro hammers exclusively in Europe, but the cases where these methods can be used in Japan, where vibration and noise regulations are severe, are very limited and should be put to practical use. It is because it is not possible.

  On the other hand, as a construction method in which a steel material having a relatively simple form such as a U-shaped steel sheet pile is built in the ground with low vibration and low noise, for example, as described in Patent Documents 1 to 3, a wing shape is formed by resistance from the ground. An excavating blade with a diameter that can be expanded to an auger (earth auger) is provided at the tip of the auger (earth auger), and a steel sheet pile along the auger axis is drilled while excavating the ground using this excavating blade. A method of press-fitting into the excavated part by the excavating blade has been put into practical use.

Patent Document 4 describes a method using a biaxial auger as a method for efficiently building a shape steel such as an H-section steel into the ground.
JP 49-89307 A JP 49-49308 A Japanese Patent Laid-Open No. 50-30314 JP-A 63-63819

The methods described in Patent Documents 1 to 3 described above are used as an excavating blade on the auger head so that the auger does not interfere with the steel sheet pile when the auger is pulled out after the steel sheet pile is built to a predetermined depth. The excavator blades are equipped with a mechanism for expanding and contracting (expanding and closing blades), and using the excavator blades, excavating the part where the steel sheet piles are built, while pressing the steel sheet piles in parallel, when, in order to perform smoothly press-fit the steel sheet piles, drilling range by the drilling wing as shown in FIG. 10 needs to be adapted to substantially encompass the steel sheet pile 1a cross section (in the figure, d ₀ is the stirring blade The outer diameter when the diameter is reduced, and d ₁ is the outer diameter when the diameter is expanded).

  If this method is used, for example, the earth retaining steel material 1 (a combined steel sheet pile in which the H-section steel 5 is integrated with the steel sheet pile 2 by welding or the like) as shown in FIG. It is necessary to arrange as shown in

However, in the case of FIG. 12, since the ratio of the outer diameter d ₁ of the auger excavating blade to the larger diameter and the outer diameter d ₀ of the auged excavating blade has to be remarkably increased, the excavating blade becomes enormous and the excavating capacity is increased. There is a problem that the diameter cannot be reduced (closed blade) at the same time.

  Further, when the multi-axis auger shown in FIG. 13 is used, the mechanism of the motor / reduction gear of the drive unit becomes complicated and the device becomes expensive. Once the combined steel sheet piles are spread out, the work of rearranging the multi-axis auger at a predetermined interval is necessary, which causes a problem that the construction efficiency is lowered.

  The invention described in Patent Document 4 is an invention in which the biaxial auger can be quickly separated and rearranged in order to solve the above-mentioned problem, but in any case, a special device is required and the device is expensive. However, there is a problem that it goes against the purpose of reducing construction costs.

The present invention is intended to solve the above-described problems in the prior art. Conventionally, due to its form and size, steel materials that are difficult to build and require great construction costs. also, in a low vibration, low noise, and an object of the present invention to provide a construction included how that can be efficiently and inexpensively in construction.

  The invention according to claim 1 of the present application is the construction of a steel material in which a plurality of steel materials are built in a wall shape in the ground by sequentially repeating the step of building the steel materials simultaneously with the excavation while excavating the ground with an auger. In the installation method, after the steel material to be built later is excavated in the preceding excavation range excavated in the construction of the steel material constructed earlier and in the construction of the steel material to be constructed later It is built to straddle the line excavation range.

  In the inventions according to Patent Documents 1 to 4 described in the background art section, the steel material to be built in the ground was excavated when the steel material was built, including the case of the biaxial auger of Patent Document 4. In the present invention, the steel material is excavated at the time of the excavation range and the preceding excavation range excavated at the time of the construction of the steel material built before that, and at the time of the construction of the steel material It was decided to build over the subsequent excavation area.

  Therefore, the drilling diameter required for the construction of the steel material is greatly reduced compared to the conventional single-shaft auger, and the mechanism of the auger itself is single-shaft although it is almost the same as that of the two-shaft auger. Therefore, the combined cost of the construction cost and the cost of the apparatus can be greatly reduced as compared with the conventional construction method, and efficient and stable construction is possible in terms of workability and the mechanism of the apparatus.

  In addition, excavation in the present invention does not necessarily mean that excavated soil is discharged, as in the case of conventional steel sheet pile construction methods, etc. Steel material can be constructed by auger excavation blades, etc. It is a concept that includes the case where the earth and sand are only loosened to a certain state.

  Moreover, the steel materials built in a wall shape may be connected using a joint or the like, and there may be a space between the steel materials without being connected.

  Claim 2 is the steel material erection method according to claim 1, wherein the steel material to be built first is a preceding excavation range excavated without steel material first, and the steel material to be built first. It is constructed so as to straddle a subsequent excavation range excavated at the time of embedding.

  As for the first steel material to be built, there is no steel material to be built before that, so the pre-excavation range that was dug without steel material and the subsequent excavation range that was excavated when the steel material was built It was built so as to straddle.

  As a method other than the construction method according to claim 2, for example, when the steel material to be built first has a shape different from that of the steel material to be built later, the first steel material is the same as the conventional method. The excavation of the portion where the steel material is built and the steel material construction may be performed simultaneously.

  According to a third aspect of the present invention, in the steel material erection method according to the first or second aspect, the excavation blades having different excavation diameters are provided at the distal end portion of the auger so that the excavation diameter of the excavation blades on the rear end side is larger than the front end side. Further, a plurality of stages are provided in the axial direction of the auger, and at least a drilling blade having the maximum drilling diameter can be expanded.

  In the method of excavating the ground with the auger and laying the steel material at the same time, a casing is arranged outside the excavation shaft equipped with the auger screw, and the steel material is press-fitted in a state of being arranged outside the casing, etc. In that case, the excavation blade at the tip of the auger is made a mechanism that can be expanded and contracted, and the excavation range of the steel material is excavated with the diameter of the excavation blade expanded, and the steel material is built to a predetermined depth. Then, it can be pulled up through the casing by reducing the diameter.

  When the excavation diameter is large, as described in Patent Documents 1 to 3, excavation blades that can be expanded in diameter are often used, but the excavation blades are provided in a plurality of stages, and the rear end side from the front end side. By increasing the excavation diameter of the excavation blades, it is possible to reduce the burden on each excavation blade and increase the overall excavation capability.

  As for the mechanism for expanding the diameter, as in the inventions described in Patent Documents 1 to 3, the combination of pins and stoppers expands and closes the blade in the vertical plane. There is no particular limitation such as a type that can be expanded or contracted in a horizontal plane, such as an expansion / contraction mechanism in a stirring blade for stirring and mixing of earth and sand, or a mechanical expansion / contraction mechanism.

  The excavation of the ground with an auger should be done with consideration for the flow of earth and sand, so that multiple stages of excavation blades do not kill the flow of earth and sand. There are a method of adjusting the approach speed and a method of increasing the distance between multiple stages of excavating blades.

Moreover, as later described in the embodiment of FIG. 4, the drilling blade in a plurality of stages, the use of the auger equipment which is installed out of phase in the rotational direction, between the drilling wing approach speed and a plurality of stages of the auger Regardless of the distance, a suitable sediment flow can be formed.

  According to a fourth aspect of the present invention, there is provided the steel material erection method according to the first or second aspect, wherein the excavating blade having a different excavating diameter is provided at the distal end portion of the auger. Is provided in a plurality of stages in the axial direction of the auger.

  When a plurality of digging blades capable of expanding the diameter are provided, the digging blade is not attached to the inner side of the digging blade because it becomes a hindrance at the time of folding and contracting, but in the case of the invention according to claim 4, The folded part of the wing can be supplemented by excavation with a smaller diameter drilling wing below.

  A fifth aspect of the present invention is the method of building a steel material according to the third or fourth aspect, wherein the excavation of the ground by the auger is performed by excavation by the excavation blade and excavation having a diameter larger than the excavation diameter by the excavation blade. Or it is characterized by carrying out by the combined use of excavation by high pressure injection of gas.

  For example, in a corner part where the continuous direction changes, such as a retaining wall, when excavation with a larger diameter is desired due to the construction position of the steel material, expanded excavation by using high-pressure injection together The soil can be loosened to a larger diameter range than the wing excavation diameter, and the resistance of the ground to the press-fitting of steel can be reduced.

  This high-pressure jet is provided with an injection port at the tip of the auger excavation shaft or blade, or at the tip of the other auger, and drilled fluid (such as cement or other solidified material such as water) fed through the auger excavation shaft. (Which may be mixed) is performed by high-pressure injection in the radial direction from the injection port.

  According to a sixth aspect of the present invention, in the steel material erection method according to the third, fourth, or fifth aspect, the excavating blade that is capable of expanding the diameter is a rotating shaft for bending a tip portion of the excavating blade with respect to a base portion of the excavating blade. And a stopper for maintaining the expanded state of the excavating blade, so that the diameter of the excavating blade is expanded by the resistance of the earth and sand at the time of forward rotation of the auger and the diameter is reduced by the resistance of the earth and sand at the time of reverse rotation of the auger A casing having a projecting portion extending in the axial direction of the auger is disposed on the outer peripheral portion of the excavating shaft of the auger so as to be relatively movable in the axial direction of the auger. Even if the diameter reduction due to the resistance of the earth and sand is insufficient, the excavation blade is contracted to the inner diameter of the casing or less by bringing the protrusion into contact with the tip of the excavation blade when the auger is reversed. It is characterized by

  Here, the forward rotation of the auger refers to the time when the excavating blades excavate the earth and sand by the rotation of the auger, and the reverse rotation of the auger refers to the time when the auger is rotated in the direction opposite to the forward rotation.

  A structure in which a pin and a stopper are provided on the wing at the tip of the auger and the wing is expanded and contracted by utilizing the resistance of the excavated earth and sand has been conventionally known, but in the conventional structure, the earth and sand loosened by excavation is known. There is a case in which the diameter reduction is insufficient due to the small resistance received from the wing or the earth and sand sandwiched inside the folded wing (folding direction).

  In the invention which concerns on Claim 6, when the protrusion part is provided in the front-end | tip part of a casing and the excavation blade is not fully reduced in diameter, the protrusion part of a casing collides with this excavation blade, and it is compulsorily an excavation blade The diameter can be reduced.

  According to the steel erection method of the present invention, the excavation diameter required for erection of the steel material is greatly reduced as compared with the conventional single-shaft auger, and the mechanism is simpler than that of the multi-shaft auger. In addition, compared to the conventional construction method, the overall cost combining the construction cost and the equipment cost can be greatly reduced, and efficient and stable construction is possible.

  The invention of the present application is a construction method in which excavation by excavating blades of an auger and construction of a steel material are performed at the same time, and a steel material having a large cross-sectional performance with a variation in size can be constructed with low vibration and low noise.

1 (a) to 1 (c) show an earth retaining steel material 1 in which an asymmetric U-shaped steel sheet pile 2 and H-shaped steel 5 similar to those shown in FIG. The case where it is built in a wall shape is schematically shown, and construction is performed according to the following procedure.
(1) First, only excavation in the excavation area a is performed without retaining steel (see Fig. 1 (a)).
(2) While excavating the next excavation range b, the earth retaining steel material 1 set on the auger is simultaneously press-fitted so as to straddle the excavation range a and the excavation range b (see FIG. 1 (b)).
In this press-fitting, for example, the upper end portion of the earth retaining steel material 1 is held by a steel material grasping device 17 provided in the auger 11 as shown in FIG. It is performed by adding (in FIG. 3, illustration of the earth retaining steel material 1 is omitted).

(3) While excavating the next excavation range c, the earth retaining steel material 1 set on the auger 11 is press-fitted so as to straddle the excavation range b and the excavation range c (see FIG. 1 (d)).
(4) Repeat the same work to build a retaining wall in the ground.

  In the present embodiment, the asymmetric U-shaped steel sheet pile 2 that forms part of the earth retaining steel material 1 has a lateral cross-sectional shape of the joints 3 and 4 at both ends, and one of the joints 3 and 4 that engage with each other is inward. In the state where the other is formed outward and the cross-sectional shape of the steel sheet pile is aligned in the same direction, a plurality of steel sheet piles can be connected in a straight line. A continuous earth retaining steel wall can be formed in a state where the cross-sectional shape is aligned in the same direction together with the integrated H-section steel 5.

  FIG. 2 shows an embodiment of the tip attachment 21 according to the present invention. A tip excavation bit 25 and a two-stage expandable / contractible excavation blade 26 are provided at the tip of the excavation shaft 14 having a screw blade 24 on the outer periphery. , 27 are provided.

The maximum diameter D _L1 when the upper excavating blade 27 is expanded is larger than the maximum diameter D _S1 when the lower excavating blade 26 is expanded. The excavating blades 27 excavate to a larger diameter.

These lower and upper excavation blades 26 and 27 have excavation bits 26b and 27b at their tips, respectively, and when the auger 11 (see FIG. 3) rotates in the excavation direction, it is extended by a mechanical stopper, that is, maximum. When the state of the diameter is maintained and the auger 11 is rotated in reverse, the auger 11 is bent at the positions of the pins 26a and 27a due to the resistance of earth and sand to reduce the diameter (minimum diameter D ₀ ), and in this state, it is pulled up through the casing 14.

  In the figure, reference numeral 23 denotes a connecting portion for connecting to the excavation shaft 16 of the auger 11, and 28 denotes a discharge port for ejecting air or water during excavation.

  FIG. 3 is a schematic view of the entire auger. The auger drive unit 13 moves up and down along the leader mast 12, and the excavation shaft 14 is attached to the casing coupling 15 located below the drive unit 13. A steel material gripping device 17 for gripping the earth retaining steel material 1 is provided on the outside of the casing 16, and the gripped earth retaining steel material 1 is excavated in the ground A by the hydraulic cylinder 18 in accordance with the excavation of the auger 11. Pressed into.

FIG. 4 shows the relationship between the arrangement of the excavating blades at the tip of the auger and the flow of excavated soil. In the illustrated example, in order to prevent the excavation blades from killing the flow of earth and sand during excavation of the ground with the auger, the excavation bit 25 at the tip end is shown in FIG. 4 (b) as a bottom view. The lower-stage expanded digging blade 26 and the upper-stage expanded digging blade 27 are arranged with a phase shifted in the circumferential direction. By doing so, the outer periphery of the shaft portion 22 is spirally wound, A smooth earth and sand flow from S ₀ to S ₁ of 4 (a) is formed.

  5 and 6 show an embodiment in which excavation by high-pressure injection of air or water is used in combination with excavation by excavation blades.

  FIG. 5 shows a case where the present invention is applied to a corner portion of a retaining wall made of a retaining steel material 1 made of a combination of an asymmetric U-shaped steel sheet pile 2 and an H-shaped steel 5. Then, in relation to the excavation radius, as shown in FIG. 5 (a), a non-excavated portion u is generated, and the placement resistance of the next earth retaining steel material 1 is increased. Becomes difficult.

  On the other hand, as shown in FIG. 6, in addition to the normal discharge port 28, a high-pressure injection port 29 is provided at the tip of the auger, and high-pressure air or water is injected from here, so The excavation range is larger than the excavation diameter, and the excavation range is expanded as shown in FIG. 5 (b) (in the figure, e is the excavation diameter by the upper-stage expanded excavation blade 27, h is the excavation diameter by high-pressure injection), This part of the earth retaining steel material 1 can also be built smoothly.

  7 to 9, a casing 31 (corresponding to the casing 16 and the tip casing 16 a in FIG. 3) is arranged outside the shaft portion 22 of the auger, and the diameters of the excavating blades 26 and 27 are reduced at the tip portion of the casing 31. One embodiment in the case of providing a square protrusion 32 for ensuring the above is shown.

  FIG. 7 shows the positional relationship between the tip of the auger and the casing 31 during ground excavation with the auger rotated in the forward direction. The casing 31 and its angular protrusion 32 are located above the upper diameter expanded excavation blade 27. Then, due to the forward rotation of the auger, the diameter of the lower and upper diameter agitating blades 26 and 27 is increased by the resistance from the surrounding earth and sand, and the earth retaining steel material (not shown) is built in while excavating the earth and sand. In the figure, reference numeral 33 denotes a guide member for erection of earth retaining steel.

  FIG. 8 shows the positional relationship between the auger tip and the casing 31 when the earth retaining steel material is built up to a predetermined depth and then gradually pulled up while reversing the auger. When the tip end portion of the stub is relatively approached, the tip end of the angular projection 32 enters between the upper diameter expanded excavation blades 27 and further between the lower diameter expanded excavation blades 26.

  At this time, the enlarged diameter excavation blades 26 and 27 are subjected to resistance in the opposite direction to that during excavation from the surrounding excavation earth and sand, and are bent at a pin position in the middle of the blade. When the resistance is small, the diameter is not reduced within the inner diameter of the casing 31, and it is considered that the auger can be pulled out as it is. FIG. 8 shows a state where the diameter reduction of such diameter-expanded excavating blades 26 and 27 is insufficient.

  FIG. 9 shows that the auger reversal progresses, and the angular protrusions 32 provided at the tip of the casing 31 collide with the enlarged diameter excavating blades 26 and 27. In the state shown in FIG. The diameter excavation blades 26 and 27 are shown to be forcibly folded to the inside of the inner diameter of the casing 31 by the angular protrusions 32. In this state, the tip of the auger can be smoothly pulled out through the inside of the casing 31.

  In the illustrated embodiment, a taper 32a is provided on one side of the angular protrusion 32 (the side that comes into contact with the enlarged diameter excavating blades 26 and 27 when the auger rotates reversely) to reduce the resistance received by the angular protrusion 32. However, the shape is not particularly limited as long as the diameter-excavated blades 26 and 27 can be surely forcibly reduced in diameter without being limited to the rectangular shape as illustrated.

(a)-(c) is the top view which showed roughly the construction procedure in the erection method of this invention. The tip attachment according to the present invention is shown, in which (a) is a front view, (b) is a side view, and (c) is a bottom view. It is an outline figure of the whole earth auger concerning the invention in this application. (a) is a front view showing the relationship between the arrangement of excavating blades and the flow of excavated sediment at the tip of the auger, (b) is a bottom view thereof, (c) is a cross-sectional view along AA, and (d) is a cross-sectional view along BB. It is sectional drawing. It is a figure for demonstrating combined use of the high pressure injection in excavation, (a) is a top view when not performing high pressure injection, (b) is a top view when performing high pressure injection. (a) is the front view which shows an example of the tip attachment in the case of using high pressure injection together, (b) is the side view which showed notionally the excavation range by high pressure injection. For one embodiment in the case where an angular projection for ensuring the diameter reduction of the excavation blade is provided at the tip of the casing, the positional relationship between the auger tip and the casing during ground excavation is shown. (a) is a front view and (b) is a side view. FIGS. 7A and 7B show the positional relationship between the auger tip and the casing when the auger is gradually lifted while reversing from the state of FIG. 7, wherein (a) is a front view and (b) is a side view. FIG. 8 shows the positional relationship between the auger tip and the casing when the diameter of the excavating blade is completely reduced by the angular projections at the tip of the casing, (a) is a front view, b) is a side view. It is the top view which showed schematically the construction method of the conventional U-shaped steel sheet pile. It is the front view seen from the steel material end surface side which showed an example of the earth retaining steel material which integrated the asymmetrical U-shaped steel sheet pile and H-section steel. It is a top view which shows roughly an example of the construction method by the conventional erection method of the steel material of FIG. It is a top view which shows roughly the other example of the construction method by the conventional erection method of the steel material of FIG.

Explanation of symbols

A: Ground, S ₀ , S ₁ ... Sediment flow, a, b, c ... Excavation range, e ... Excavation range by excavation blades, h ... Excavation range by high pressure injection, u ... Non excavation part,
DESCRIPTION OF SYMBOLS 1 ... Earth retaining steel material, 1a ... U-shaped steel sheet pile, 2 ... Asymmetric U-shaped steel sheet pile, 3, 4 ... Joint, 5 ... H-section steel,
DESCRIPTION OF SYMBOLS 11 ... Auger, 12 ... Leader mast, 13 ... Drive part, 14 ... Excavation shaft (auger screw), 15 ... Casing coupling, 16 ... Casing, 16a ... End casing, 17 ... Steel material gripping device, 18 ... Hydraulic cylinder,
DESCRIPTION OF SYMBOLS 21 ... Tip attachment, 22 ... Shaft part, 23 ... Connection part, 24 ... Screw blade, 25 ... Tip drill bit, 26 ... Lower diameter expansion drill blade, 26a ... Pin, 26b ... Drill bit, 27 ... Upper diameter expansion drill blade 27a ... pin, 27b ... excavation bit, 28 ... discharge port, 29 ... high-pressure injection port, 31 ... casing, 32 ... square protrusion, 32a ... taper part, 33 ... guide member

Claims (6)

  Steel materials to be built later in the method of building steel materials in which a plurality of steel materials are built in a wall shape by sequentially repeating the process of building steel materials at the same time as excavation while excavating the ground with an auger To span the preceding excavation range excavated at the time of the construction of the steel material previously built and the subsequent excavation range excavated at the time of the construction of the steel material to be built later A construction method of steel material characterized by construction.   The steel material to be built first straddles the preceding excavation range excavated without the steel material first, and the subsequent excavation range excavated when the steel material to be built first is built. The steel material erection method according to claim 1, wherein   Excavation blades having different excavation diameters are provided at the tip of the auger in a plurality of stages in the auger axial direction so that the excavation diameter of the excavation blade on the rear end side is larger than the front end side, and at least the maximum excavation diameter The method for erection of a steel material according to claim 1 or 2, wherein the diameter of the excavating blade having a diameter can be increased.   The auger blades having different digging diameters are provided at a plurality of stages in the axial direction of the auger so that the digging diameter of the digging blade on the rear end side is larger than the tip side. 3. The method for building a steel material according to claim 1, wherein the steel material is erected.   4. The excavation of the ground by the auger is performed by a combination of excavation by the excavation blade and excavation by high-pressure injection of liquid or gas for excavation having a diameter larger than the excavation diameter by the excavation blade. Or the construction method of steel materials of 4.   The excavating blade that is capable of expanding the diameter includes a pin that serves as a rotation axis for bending the tip of the excavating blade with respect to the base of the excavating blade, and a stopper for maintaining the expanded state of the excavating blade, The diameter of the excavating blade is increased by the resistance of the earth and sand at the time of forward rotation of the auger and the diameter of the excavation blade is reduced by the resistance of the earth and sand at the time of reverse rotation of the auger. A casing having a protruding portion extending in the axial direction of the auger is disposed so as to be relatively movable in the axial direction of the auger, and even when the diameter of the excavating blade due to the resistance of the earth and sand is insufficient, 6. The construction of a steel material according to claim 3, wherein the projecting portion is brought into contact with a tip portion of the excavating blade, whereby the excavating blade is reduced in diameter to be equal to or less than an inner diameter of the casing. Method.

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