WO2011125710A1 - 脱気工程を含む鋼杭打設工法 - Google Patents
脱気工程を含む鋼杭打設工法 Download PDFInfo
- Publication number
- WO2011125710A1 WO2011125710A1 PCT/JP2011/057966 JP2011057966W WO2011125710A1 WO 2011125710 A1 WO2011125710 A1 WO 2011125710A1 JP 2011057966 W JP2011057966 W JP 2011057966W WO 2011125710 A1 WO2011125710 A1 WO 2011125710A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- steel pile
- hammer
- fluidized
- vibration
- amplitude
- Prior art date
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/18—Placing by vibrating
Definitions
- the present invention relates to a steel pile placing method using a fluidized solidifying material such as cement milk, and more particularly to a steel pile placing method for degassing the fluidized solidified material in the formation of a rooted portion.
- the “fluidized solidifying material” in the present specification means various fluidized kneaded materials containing cement, which solidify over time after placing.
- cement milk in which cement and water (including additives such as admixtures in some cases) are kneaded, soil cement in which clay is kneaded in soil, mortar material in which cement milk is kneaded in sand, cement milk in sand (fine Aggregate) and concrete material kneaded with gravel (coarse aggregate) are fluidized solidification materials.
- the “steel pile” in the present specification means civil engineering and architectural steel materials that are placed in the ground, and includes, for example, H-shaped steel, steel sheet piles, steel pipes, and the like.
- the fluidized solidifying material is used to form a structure of a building by placing it on a formwork, or to form an underground structure by being injected or injected into the ground.
- the fluidized solidified material contains relatively large bubbles due to air being trapped in the gap between cement and water in the process of kneading, pumping and placing.
- the solidified body solidified while containing such bubbles has a weaker strength than those not containing them. Therefore, it is preferable to remove excess bubbles from the fluidized solidified material after placement, that is, to deaerate.
- the degassing treatment of the fluidized solidifying material is generally referred to as compaction.
- the compaction is performed by giving an appropriate vibration energy to the fluidized solidified material. As a result of removing excess bubbles by vibration, a solid and high-strength solidified body is obtained.
- a rod-like vibrator as described in Patent Document 1 is known as a general compaction vibration device.
- the rod-like vibrator generates a vibration having a frequency of 116.7 to 200 Hz and an amplitude of about 0.5 to 1.25 mm (“amplitude” in the present specification means half of the peak-to-peak of the vibration wave). ).
- the frequency of the rod-like vibrator is relatively high in the vibration device. In the high frequency region, the vibration energy is greatly attenuated, so that it is difficult for the vibration to reach far away. For this reason, the rod-like vibrator can obtain a degassing effect only in the vicinity thereof.
- the rod-like vibrator can be used only for the fluidized solidified material placed so that the surface is exposed. Therefore, it cannot be used for the fluidized solidified material placed in the ground. Conventionally, there has been no effective means for degassing the fluidized solidifying material used to form underground structures.
- a synthetic steel pile with soil cement As an underground structure using a fluidized solidifying material, for example, a synthetic steel pile with soil cement is well known.
- a vibro hammer is attached to the base end of the steel pile, and the steel pile is penetrated into the ground while relaxing the ground resistance by giving vibration energy to the steel pile.
- a steel pile driving method using a water jet is also known.
- a plurality of transfer pipes are attached along the axial direction of the steel pile, and the injection nozzle is arranged near the tip of the steel pile.
- the ground resistance is relaxed by excavating the ground by spraying high-pressure water from the spray nozzle while giving vibration by vibro hammer.
- a solidified part is formed in the front-end
- the root hardening part is a solidified body of a fluidized solidifying material. The end support force for the steel pile is ensured by the solidified part.
- the fluidized solidified material in the steel pile placing method of Patent Document 2 also contains excess bubbles. Therefore, in order to form a stronger root-solidifying part, it is desirable to degas the fluidized solidified material. However, it is impossible to apply a general rod-like vibrator to the fluidized solidified material placed in the ground. Therefore, until now, there has been no idea of degassing the fluidized solidified material that is injected into the ground and solidified.
- the protrusion and the rib for improving the adhesiveness with the root hardening part are provided in the inner and outer surface of the front-end
- the method of Patent Document 2 includes a step of stopping the vibro hammer after stopping the steel pile at the planned depth (fixing depth) and injecting the fluidized solidified material for a predetermined time. As a result, the fluidized solidified material mixed with large bubbles is solidified as it is. This means that the strength of the root hardening portion is lower than the strength that should be originally obtained.
- the present invention realizes deaeration of the fluidized solidified material in the ground in order to form a solid and uniform high-strength rooted portion. Objective.
- One aspect of the present invention is a steel pile placing method for placing the steel pile into the ground using a transfer pipe disposed along the longitudinal direction of the steel pile and a vibro hammer. Injecting water from the transfer pipe and operating the vibrator hammer to penetrate the steel pile to a predetermined depth in the ground; and injecting a fluidized solidifying material from the transfer pipe; and the vibrator hammer A step of forming a solidified portion around the tip of the steel pile by operating the steel pile; after placing the steel pile at a planned depth and stopping the injection of the fluidized solidifying material, the vibro hammer is fixed A steel pile driving method having a step of degassing the fluidized solidified material by operating for a period of time.
- the vibro hammer in the step of penetrating the steel pile and the step of forming the root hardening portion, the vibro hammer is set for penetration. In the step of operating at an amplitude and degassing the fluidized solidified material, the vibratory hammer may be operated at a second amplitude set for degassing.
- the steel pile may include a linear protrusion provided on the inner surface of the tip portion.
- the steel pile may include a plate-like rib protrusion provided on the outer surface of the tip portion.
- the fluidized solidifying material can be degassed in the ground, particularly around the tip of the steel pile, a stronger underground structure can be obtained. can get.
- the amplitude of the vibratory hammer in the step of degassing the fluidized solidified material is independent of the amplitude of the vibratory hammer in the step of penetrating the steel pile and the step of forming the rooting portion. Since it sets, it is possible to deaerate a fluid solidification material better.
- the deaeration effect can be further improved by the linear protrusions provided on the inner surface of the steel pile tip.
- the plate rib protrusion provided on the outer surface of the steel pile tip can improve the adhesion between the root-solidified portion and the steel pile, and the large-diameter root A hardened part can be formed.
- FIG. 1D It is a graph which shows the deaeration effect of the fluid solidification material by the steel pile placing construction method of this invention. It is a figure which shows the selection method of a vibro hammer.
- the steel pile driving method operates the vibratory hammer for a certain time after the completion of driving the steel pile, that is, after the steel pile is positioned at the planned depth (fixing depth) and the injection of the fluidized solidifying material is stopped.
- the method has a step of degassing the unsolidified fluidized solidified material around the tip portion.
- vibro hammers Conventionally, vibro hammers have been used exclusively for placing steel piles. No attempt has been made so far to actively use the vibration energy of the vibratory hammer for degassing the fluidized solid material in the ground.
- a vibratory hammer is a vibration device having a frequency and amplitude in a completely different range from the above-described rod-like vibrator.
- the frequency of the vibratory hammer is lower and the amplitude is larger than that of the rod-shaped vibrator. Therefore, the frequency and amplitude settings for deaeration in the vibratory hammer are completely different from those of the rod-like vibrator.
- the low frequency is advantageous in that the vibration energy is moderately attenuated and vibrations easily reach far away. Also, a large amplitude is advantageous in that a large vibration energy can be obtained.
- the vibration energy is uniformly transmitted to the entire fluidized solidified material and uniformly deaerated, so that the homogeneity of the strength of the solidified body is ensured.
- the fluidized solidified material is compacted by degassing.
- degassing and compaction differ only in expression, and these terms represent the same phenomenon.
- the fluidized solidified material has the property of being liquified more easily as the number of times (frequency) of the movement of the cement particles per unit time is larger and as the relative displacement (amplitude) between the cement particles is larger. Therefore, in principle, the degree of liquefaction, that is, the deaeration effect can be adjusted by adjusting one or both of frequency and amplitude.
- the frequency can be adjusted, but the amplitude can be adjusted more widely and easily. Therefore, the vibratory hammer is operated with the first amplitude set for penetration when the steel pile penetrates, and with the second amplitude set for deaeration when the fluidized solidified material is deaerated. By this, it is possible to realize the optimal penetration of the steel pile and the formation of the solidified portion.
- the protrusion provided at the tip of the steel pile generates a pressure wave around the vibration of the vibratory hammer transmitted during deaeration. This pressure wave also has a degassing effect. Therefore, these protrusions have an effect of further enhancing the deaeration effect due to vibration of the vibratory hammer.
- FIG. 1A is a side view of a steel pile
- FIG. 1B is a plan view
- FIG. 1C is a partially cutaway cross-sectional perspective view schematically showing the state of the periphery of the steel pile front end portion (root consolidation portion) after completion of construction.
- FIG. 1D is a partially enlarged view of a plate-like rib protrusion provided on the outer surface of the tip of the steel pile.
- FIG. 1E is a cross-sectional view taken along line AA of FIG. 1D.
- a steel pile 1 shown in FIG. 1A is a steel pipe pile.
- the application object of the present invention is not limited to steel pipe piles, and includes steel pipe sheet piles, H-shaped steel piles, and the like.
- the outer diameter of the steel pile 1 is, for example, 600 to 1500 mm.
- a plurality (four in the illustrated example) of transfer pipes 3 are disposed on the outer surface of the steel pile 1 along the axial direction (longitudinal direction) of the steel pile.
- the transfer pipe 3 may be attached to the inner surface of the steel pile 1.
- Inside the transfer pipe 3 is a pipe line for pumping water or a fluidized solidifying material.
- the tip of the transfer pipe 3 is located near the tip of the steel pile 1.
- At the tip there is an injection port 3a of an appropriate injection nozzle (not shown).
- the diameter of the injection port 3a is, for example, 3 to 8 mm.
- the proximal end of the transfer pipe 3 is separated from the outer surface of the steel pile 1 in the vicinity of the proximal end of the steel pile 1 and is connected to a device (not shown) installed on the ground.
- These devices are a switching device between water and a fluidized solidifying material, a water and fluidized solidified material delivery device, a water tank, a kneading device, and the like.
- the transfer pipe 3 may be pulled out from the steel pile 1 at the final stage of construction and collected on the ground surface.
- a plurality of plate-like rib protrusions 1b protruding in the radial direction may be attached to the outer surface near the tip of the pile body 1a. These plate-like rib protrusions 1b are attached so that the plate surface is parallel to the axial direction of the steel pile. Such a plate-like rib protrusion 1b is effective when forming a root-solidifying part having a larger diameter.
- the shape of the plate-like rib protrusion 1b is, for example, a rectangle or a shoulder drop rectangle (a shape in which one or more corners of the rectangle are cut out).
- the number of plate-like rib protrusions 1b is 2 to 5, for example, and these are arranged at equiangular intervals in the circumferential direction of the steel pile 1 as shown in FIG. 1B, for example.
- the plate-like rib protrusion 1b is formed of a striped steel plate.
- elongated small protrusions 1b1 having inclinations opposite to each other are alternately arranged to form a substantially lattice-like pattern as a whole.
- the size of one small protrusion 1b1 is, for example, 28 mm long and 4.5 mm wide.
- the arrangement pattern of many elongate small protrusion 1b1 is not restricted to the example of illustration.
- a linear protrusion (slip stopper, slip keeper) 1c may be attached to the inner surface of the tip end portion of the pile body 1a.
- the illustrated linear protrusion 1c is a plurality of annular protrusions arranged horizontally at a predetermined interval.
- the linear protrusion 1c may be a spiral protrusion instead of the plurality of annular protrusions.
- the root hardening part C1 is formed in the range from the predetermined depth (maximum depth) D4 of the steel pile 1 to the drawing depth D1.
- the drawing depth D1 is substantially the same position as the upper end of the support layer (interface between the intermediate layer and the support layer) D2.
- the final planned depth (fixing depth) D3 of the steel pile 1 is located above the predetermined depth D4.
- the root hardening part C1 has a larger diameter than the steel pile 1.
- a part of the fluidized solidified body penetrates into the inside of the steel pile 1 and solidifies, so that the root hardening portion C1 and the tip of the steel pile 1 are integrated. As a result, the tip support force of the steel pile 1 is ensured.
- the plate-shaped rib protrusion 1b and the linear protrusion 1c are provided in order to improve the adhesiveness and deaeration effect of the root hardening part C1 and the steel pile 1.
- the supply of the fluidized solidifying material is substantially stopped and the vibro hammer is operated to perform the deaeration process, that is, the compacting process. .
- cement milk in which cement and water (including additives such as admixtures in some cases) are kneaded may be used.
- the ratio of water to cement (W / C) is 50 to 150%.
- the vibratory hammer is attached to the upper end of the steel pile, that is, the ground, but the vibration is transmitted to the tip of the steel pile in the ground through the steel pile.
- a low frequency of about 11.7 to 18.3 Hz is used for compaction in the ground with a vibro hammer. Low-frequency vibrations are less damped and can be transmitted far from one vibration source. In this respect, it is reasonable to use a vibro hammer to compact the fluidized solidifying material in the ground.
- the rod-like vibrator and the vibro hammer used in the steel pile placing method according to the present embodiment are numerically compared.
- Compaction performance of fluidity solidifying material by the vibration device can be evaluated by the vibration acceleration ⁇ and the vibration compaction energy E c. By calculating these numerical values, the compaction performance of both can be compared.
- the “vibration compaction energy” means vibration energy used for compaction.
- Table 1 summarizes the comparison results of the vibro-hammer to be used in the vibration acceleration ⁇ and for vibration compaction energy E c, typical rod-like vibrator and the steel piling ⁇ method according to the present embodiment.
- the motor output was 90 kW, 120 kW, 180 kW, and 240 kW. A method for selecting an appropriate vibratory hammer will be described later.
- the vibration acceleration ⁇ and the vibration compaction energy E c were calculated using the values and formulas of each parameter shown in the table.
- g is a gravitational acceleration (9.81 m / s 2 ).
- Oscillating mass W v of the vibro-hammer in Table 1 is the vibration mass of only vibro-hammer.
- the vibration mass of only a vibro hammer was used.
- the vibration acceleration ratio ⁇ r was determined so that the ratio of the rod-like vibrator to the vibratory hammer was maximized in the target frequency range.
- the vibration acceleration ratio ⁇ r was about 75: 1. That is, the vibration acceleration ⁇ of the rod-like vibrator is at most 75 times that of the vibratory hammer.
- vibration compaction energy E c large vibro-hammer the oscillating mass has a dominant numbers compared to bar-shaped vibrator. Therefore, the vibration compaction energy E c, the ratio of the rod-like vibrator and vibro-hammer in a frequency range of interest was determined vibration compaction energy ratio E cr to minimize.
- the vibration compaction energy ratio E cr was about 1: 180. That is, vibration compaction energy E c of the vibro-hammer is 180 times that of at least the rod-like vibrator.
- vibro-hammer is the inferior vibration acceleration eta, compensates the predominant vibration compaction energy E c, it can be seen and is capable of exhibiting a rod vibrator more compaction performance.
- the “normal amplitude” of a vibratory hammer is a value set for steel pile penetration.
- the minimum required amplitude A of the vibro hammer set for compaction is 5 mm. Such a large amplitude can only be obtained at a low frequency with a large amount of eccentric moment.
- a vibration hammer having an amplitude that can correspond to the deaeration process can be generated and a vibration hammer that is variable from an amplitude suitable for the penetration process to an amplitude suitable for the deaeration process is used. To do.
- the vibration forced deaeration time required for vibration compaction will be examined.
- the insertion interval of the rod-shaped vibrator is about 50 cm
- the compaction time t B per place is about 15 to 20 seconds.
- a compaction time t B in the rod-shaped vibrating machine, using the ratio E cr ratio eta r and vibration compaction energy of vibration acceleration as shown in Table 1, degassed time t v of the vibro-hammer is given by the following equation It is done.
- t v ⁇ ⁇ t B ⁇ ⁇ r / E cr t v: vibro-hammer vibration forced degassing time (in seconds)
- ⁇ Margin addition time coefficient
- ⁇ r Vibration acceleration ratio
- t B Vibration forced deaeration time (seconds) in a rod-shaped vibrator
- E cr Vibration compaction energy ratio
- ⁇ is a coefficient multiplied to ensure a sufficient vibration forced deaeration time, and it is sufficient to set it to 2 to 3.
- Table 2 shows the calculation results.
- Each value of the vibration acceleration ratio ⁇ r and the vibration compaction energy ratio E cr used in the calculation of Table 2 is a value in which a loss of the vibration acceleration ⁇ due to the frictional force with the soil in the vibratory hammer is estimated to be about 10%.
- vibration compaction energy is transmitted 100% because it is inserted directly into the fluidized solidified material.
- the vibratory hammer in the case of a vibratory hammer, the vibratory hammer is located on the ground and the fluidized solidified material is present in the ground, so that loss due to friction with the soil is unavoidable in the vibration transmission process. Therefore, the vibration compaction energy of the vibratory hammer is not transmitted 100% to the fluidized solidified material and has a loss of about 10%.
- the deaeration time in the vibratory hammer is about 19 to 29 seconds. Therefore, it is considered that about 30 seconds is sufficient for the deaeration time in the vibratory hammer even if the maximum is assumed.
- FIG. 2 is a graph showing an image of the compaction effect of the fluidized solidified material due to the vibration of the vibratory hammer.
- the horizontal axis is the vibration forced deaeration time.
- the vertical axis represents the density of the fluidized solidified material.
- the amplitude for penetrating the steel pile with a vibro hammer is at least about 3 mm by rule of thumb, usually 3 to 6 mm.
- the amplitude for improving the deaeration effect of the fluidized solidifying material in the ground by vibro hammer is preferably set to 5 to 10 mm, which has not been conventionally employed. This is because large vibration compaction energy is required. Therefore, in the steel pile placing method according to the present embodiment, a vibro hammer having a variable amplitude range of 3 mm to 10 mm is selected.
- the vibration acceleration ⁇ of the vibrator hammer required at the time of penetration may be set to 3.5 G or more.
- the upper limit of the vibration acceleration ⁇ is about 10 G from the upper limit of the amplitude and frequency. Therefore, the vibration acceleration ⁇ at the time of penetration is set to 3.5 to 10G.
- ⁇ Vibro hammer selection method In the steel pile placing method according to the present embodiment, using one vibro hammer, a step of penetrating the steel pile into the ground (first step, penetration step) and a step of injecting a fluidized solidified material (second step) , A root-solidifying portion forming step) and a step of degassing the fluidized solidified material (third step, degassing step). Therefore, it is necessary to select a vibro hammer model that satisfies the conditions of all processes.
- the steps (a) to (e) of the selection method of an appropriate vibrator hammer are taken as an example in the case where a steel pile of a specific standard is placed on the ground of a specific soil condition by the steel pile placing method according to the present embodiment. This will be described below.
- the standard of the steel pile made into an example is outer diameter (phi) 1000mm, plate
- FIG. 3 is a well-known “vibrator hammer selection table by mass”. Based on the steel pile mass W p 6800 kg calculated in (b) and (c) above and the penetration resistance value R13071 kN, a vibro hammer model is selected from FIG. In this example, a model with a motor output of 180 kW is selected.
- Table 3 summarizes the verification method as to whether or not the vibro hammer of a specific model is a model applicable to the steel pile placing method according to the present embodiment, particularly the first step. It is a table.
- the lower half of Table 3 shows verification items and verification results.
- the maximum amplitude of the vibratory hammer satisfies the amplitude necessary for deaeration in the third step. Since this is the most important requirement of the steel pile placing method according to the present embodiment, it will be verified first.
- the maximum amplitude A max calculated from the maximum value K max of the eccentric moment K is 8.6 mm. This satisfies the amplitude range of 5 to 10 mm necessary for underground deaeration of the steel pile placing method according to the present embodiment.
- the amplitude A calculated from the minimum necessary acceleration 3.5G for penetration using the water jet of the first step satisfies the range of amplitude 3 to 6 mm for penetration.
- the amplitude A is about 5 mm and satisfies the amplitude range for penetration. From the above, it is verified that this model is applicable to the steel pile placing method according to this embodiment, and an appropriate amplitude A in the first step is determined.
- the amplitude A is set to an appropriate value not more than the maximum amplitude A max and not less than 5 mm necessary for deaeration. For example, by setting the eccentric moment K the maximum eccentricity moments K max, the amplitude becomes 8.6 mm. At this time, the vibration acceleration ⁇ is 6.1 G. The deaeration time is a maximum of 30 seconds.
- processes (A) to (G) schematically show an example of a steel pile placing method according to the steel pile placing method according to the present embodiment.
- This construction method includes a first step (process (A) and process (B) in FIG. 4) that penetrates the steel pile 1 to a predetermined depth D4 by operating the vibro hammer 2 while jetting water from the transfer pipe 3. , A second step of injecting the fluidized solidified material from the transfer pipe 3 while operating the vibro hammer 2 to form a rooted portion around the tip of the steel pile 1 (in FIG.
- the vibro hammer 2 grips the proximal end portion of the steel pile 1 (the upper end portion in the case of driving in the vertical direction) by the chuck device. For example, two places on the circumferential upper edge of the steel pipe pile are gripped.
- the vibratory hammer 2 transmits the rotational force of the motor to the pair of eccentric weights, and generates vibrations in one direction by rotating the eccentric weights in the reverse direction. This vibration direction is used as the driving direction.
- the specifications of a typical vibro hammer for driving steel piles are, for example, a motor output of 90 to 240 kW, a frequency of 11.7 to 18.3 Hz, an eccentric moment of 420 to 3600 N ⁇ m, and a body mass of 7 to 37 t.
- a vibro hammer having a variable amplitude and a variable amplitude can be used.
- high-pressure water for example, fresh water
- W penetrates from the injection port 3 a of the transfer pipe 3 attached to the steel pile 1 in combination with the vibro hammer 2.
- the injection pressure is, for example, 3 to 15 MPa.
- the high-pressure water W excavates the ground as a water jet cutter.
- the amplitude of the vibratory hammer 2 in the penetration process is usually set to 3 to 6 mm.
- the steel pile 1 is continuously penetrated by the vibration energy and the excavation force of high-pressure water.
- the distance from the support layer upper end D2 to the penetration excavation depth D4 is, for example, about three times the outer diameter of the steel pile 1.
- the injection of the high-pressure water W is stopped.
- ⁇ Second step> At the beginning of the flowable solidifying material injection step shown in processes (C) to (E) in FIG. 4, the fluid supplied to the transfer pipe 3 is switched from water to the flowable solidified material. Then, the fluidized solidified material C is injected from the injection port 3a while operating the vibrator hammer 2, and the steel pile 1 is stopped or moved up and down within a predetermined range. The fluidized solid material C is injected at a pressure of about 15 MPa or less, for example.
- the amplitude of the vibratory hammer 2 in the fluidized solidifying material injection step is the same as the first amplitude in the first step.
- the cement particles in the fluid solidifying material are vibrated by vibration energy of the same vibro hammer as in the first step, so that the fluid particles are deaerated to some extent.
- the fluidized solidifying material since a large amount of fluidized solidifying material is supplied, sufficient deaeration cannot be performed in the fluidized solidified material injection step.
- the steel pile 1 is pulled up until it reaches a drawing depth D1 that is substantially the same position as the upper end of the support layer (interface between the intermediate layer and the support layer) D2.
- the steel pile 1 is driven from the drawing depth D1 to the planned depth (fixing depth) D3 while injecting the fluidized solidified material C.
- the flowable solidifying material injection step shown in process (C) to process (E) in FIG. 4 may be performed only once, or may be repeated a plurality of times depending on the situation such as the hardness of the ground. In the case of a hard ground, it is preferable to repeat as many times as necessary for stirring the solidified material. Thereby, a solidified part can be reliably formed in the front-end
- ⁇ Third step> In the deaeration process shown in process (F) of FIG. 4, first, after reaching the planned depth (fixing depth) D3 and stopping, the supply of the fluidized solidifying material is stopped at the position of the planned depth (fixing depth) D3. .
- a fluid solidification material you may supply a very small amount of fluidity solidification materials as a minimum required pressure instead of stopping completely. This is to prevent clogging of the injection nozzle.
- a state in which only a very small amount of the fluidized solidifying material is supplied to prevent clogging is regarded as a state in which the supply of the fluidized solidifying material is substantially stopped. This is because it is not a supply for forming a root solidified part.
- the amplitude of the vibratory hammer 2 is set to a second amplitude suitable for deaeration, and the vibratory hammer 2 is operated for a certain time, for example, about 30 seconds.
- the amplitude of the vibratory hammer 2 in the deaeration process is set to 5 to 10 mm.
- linear protrusions slip prevention, slip keeper
- the support pressure due to the vertical vibration of these linear protrusions generates an axial pressure wave and is applied to the fluidized solidified material, thereby further enhancing the deaeration effect.
- these linear protrusions have a function as a slip stopper (slip keeper) that suppresses slipping on the contact surface with the fluidized solidified material after solidification, whereby vibration can be transmitted efficiently.
- slip stopper slip keeper
- the plate-like rib protrusion performs horizontal vibration as well as vertical vibration.
- the pressure wave generated by the horizontal vibration of the plate-like rib protrusion also enhances the deaeration effect. Further, by using a striped steel plate or the like, the deaeration effect is improved by providing another small protrusion on the plate surface.
- the air removed from the fluidized solidified material is forcibly discharged upward by the vibration of the steel pile.
- the vibratory hammer 2 is stopped.
- first amplitude of the vibrator hammer set in the first and second steps and the second amplitude set in the third step are not necessarily different from each other, and may be set to the same numerical value by chance. is there.
- FIGS. 5A and 5B are diagrams showing the process management status in construction examples 1 to 4 of the steel pile placing method according to the present embodiment.
- FIG. 5A is a graph showing the change over time in the depth of the steel pile tip position.
- FIG. 5B is a table showing process management related to time.
- process control is also performed with respect to the flow rate of water or the fluidized solidifying material.
- Process management is performed using a timer, pressure gauge, flow meter, etc.
- the section [1] [2] in FIG. 5A is an intrusion process (first process), in which the vibratory hammer is vibrated with a first amplitude and water is injected.
- Sections [3] to [7] are a flowable solidifying material injection step (second step) in which the vibratory hammer is vibrated with a first amplitude and the flowable solidified material is injected.
- section [3] is a switching process from water to a fluidized solidifying material.
- Section [8] is a deaeration process (third process), stops the fluidized solidified material, and vibrates the vibratory hammer with the second amplitude.
- the present invention it becomes possible to deaerate the fluidized solidified material in the ground, particularly in the support layer where the tip of the steel pile is located. As a result, a stronger underground structure can be obtained. .
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
- Piles And Underground Anchors (AREA)
Abstract
Description
本願は、2010年4月1日に、日本に出願された特願2010-084868号に基づき優先権を主張し、その内容をここに援用する。
また、本明細書における「鋼杭」とは、地中に打設される土木、建築用の鋼材を意味し、例えば、H型鋼、鋼矢板、鋼管なども含まれる。
(1)本発明の一態様は、鋼杭の長手方向に沿って配設される移送管と、バイブロハンマとを用いて、前記鋼杭を地中に打設する鋼杭打設工法であって、前記移送管から水を噴射するとともに、前記バイブロハンマを稼働させることにより、前記地中の所定深度に前記鋼杭を貫入する工程と;前記移送管から流動性固化材を噴射するとともに、前記バイブロハンマを稼働させることにより、前記鋼杭の先端部の周辺に根固め部を形成する工程と;前記鋼杭を計画深度に位置させて前記流動性固化材の噴射を停止した後、前記バイブロハンマを一定時間稼働させることにより、前記流動性固化材を脱気する工程と;を有する鋼杭打設工法である。
(2)上記(1)に記載の鋼杭打設工法においては、前記鋼杭を貫入する工程及び前記根固め部を形成する工程では、前記バイブロハンマを、貫入のために設定された第1の振幅にて稼動させ、且つ、前記流動性固化材を脱気する工程では、前記バイブロハンマを、脱気のために設定された第2の振幅にて稼動させてもよい。
(3)上記(1)又は(2)に記載の鋼杭打設工法においては、前記鋼杭が、前記先端部の内面に設けられる線状突起を具備してもよい。
(4)上記(1)又は(2)に記載の鋼杭打設工法においては、前記鋼杭が、前記先端部の外面に設けられる板状リブ突起を具備してもよい。
以下、本実施形態に係る、脱気工程を含む鋼杭打設工法の基本態様を、図1A~図1Eを参照して説明する。
図1Aに示す鋼杭1は、鋼管杭である。本発明の適用対象としては、鋼管杭に限られず、鋼管矢板、H形鋼杭等も含む。鋼杭1の外直径は、例えば600~1500mmである。
<棒状振動機との締固め性能の比較>
棒状振動機により地上で行う流動性固化材の締固めには、116.7~200Hz程度の高周波を用いる。高周波の振動は、振動源から離れると急激に振幅が減衰する。従って、棒状振動機の場合、流動性固化材の複数の位置に挿入(通常、約50cm毎)することにより全体の締固めを行う。しかし、地中の流動性固化材に対して棒状振動機を適用することは構造上不可能である。また、地中の所望する位置に設置することも、困難である。
次に、振動締固めに要する振動強制脱気時間を検討する。
一般に、棒状振動機の挿入間隔は50cm程度であり、1箇所当たりの締固め時間tBは、15~20秒程度である。この棒状振動機における締固め時間tBと、表1に示した振動加速度の比ηr及び振動締固めエネルギーの比Ecrとを用いて、バイブロハンマの脱気時間tvが、次式により与えられる。
tv=α・tB・ηr/Ecr
tv:バイブロハンマの振動強制脱気時間(秒)
α:余裕付加時間係数
ηr:振動加速度比
tB:棒状振動機における振動強制脱気時間(秒)
Ecr:振動締固めエネルギー比
バイブロハンマにより鋼杭を貫入するための振幅は、経験則により少なくとも3mm程度であり、通常、3~6mmである。一方、バイブロハンマにより地中で流動性固化材の脱気効果を良くするための振幅は、従来採用されていない5~10mmに設定することが好ましい。これは、大きな振動締固めエネルギーが必要だからである。
従って、本実施形態に係る鋼杭打設工法においては、3mm~10mmの可変の振幅範囲をもつバイブロハンマを選定する。
ここで、振動加速度ηが0のときの土の摩擦力を1と想定する。また、この場合の土は、粘土と想定する。粘土は、振動により摩擦力を低減することが最も困難な土質である。ウォータージェットを併用しない場合は、経験則により、振動加速度ηが5G以上になると土の摩擦力が0.2以下に低減する。ウォータージェットを併用する場合は、経験則により、振動加速度ηが3.5G以上になると土の摩擦力が0.1以下に低減する。本実施形態に係る鋼杭打設工法では、鋼杭の貫入においてウォータージェットを併用するので、貫入時に必要なバイブロハンマの振動加速度ηは、3.5G以上に設定すればよい。振動加速度ηの上限は、振幅及び周波数の上限から10G程度とする。よって、貫入時の振動加速度ηは、3.5~10Gに設定する。
本実施形態に係る鋼杭打設工法では、1つのバイブロハンマを用いて、鋼杭を地中に貫入する工程(第1工程、貫入工程)と、流動性固化材を噴射する工程(第2工程、根固め部形成工程)と、流動性固化材を脱気する工程(第3工程、脱気工程)の3つの工程を行う。従って、全工程の条件を充足するバイブロハンマの機種を選定しなければならない。
バイブロハンマの周波数を11.7~18.3Hzの範囲内の1つの周波数に決定する(この時点では具体的な機種は未定)。
単位長さ質量340kg/m及び長さ20mより、鋼杭質量Wp(kg)を次式の通り計算する。
鋼杭質量Wp(kg)=340×20=6800
貫入する箇所の土質状態は、深度とN値が記載された土質柱状図から得られる。土質柱状図に基づいて、所望する鋼杭の根入れ長さ(地中への貫入長さ)における貫入抵抗値Rを次式により計算する。
貫入抵抗値R=300N・Ap+(10N・Ni・Lc+2Ni・Ls)・As
N:最大N値
Ap:鋼杭の先端閉塞断面積(m2)
Ni:鋼杭の根入れ長さの平均N値
Lc:粘性土への鋼杭の根入れ長さ(m)
Ls:砂質土への鋼杭の根入れ長さ(m)
As:鋼杭の周長(m)
一例である各パラメータの数値を代入すると、貫入抵抗値Rは次の通りとなる。
貫入抵抗値R(kN)=300×50×0.79+(10×2×11.7+10×5×1.3+2×22.5×2.0)×3.14
=13071
図3は、公知の「質量によるバイブロハンマ選定表」である。上記(b)(c)で算出した鋼杭質量Wp6800kgと貫入抵抗値R13071kNにより、図3からバイブロハンマの機種を選定する。この例では、モータ出力180kWの機種が選定される。
モータ出力180kWの特定機種のバイブロハンマについて、本実施形態に係る鋼杭打設工法の第1工程~第3工程に適用可能な仕様であるか否か検証し、検証結果に基づき、各工程の適切な振幅Aを設定する。
表3は、特定機種のバイブロハンマが本実施形態に係る鋼杭打設工法、特に第1工程に適用可能な機種であるか否かの検証方法をまとめた表である。表3の上半分には、特定機種の仕様を表す各パラメータと、鋼杭質量Wpとを示している。表3の下半分には検証項目と検証結果を示している。
次に、第1工程のウォータージェットを併用した貫入の最低必要加速度3.5Gから計算された振幅Aが、貫入のための振幅3~6mmの範囲を満足するかを検証する。振幅Aは約5mmであり、貫入のための振幅の範囲を満足する。
以上により、本機種が本実施形態に係る鋼杭打設工法に適用可能であることが検証され、第1工程における適切な振幅Aが決定される。
第2工程では、ウォータージェットを流動性固化材に切替え、流動性固化材の噴射を行う。この第2工程においては、バイブロハンマを第1工程と同じ周波数及び同じ振幅で稼働させる。
第3工程では、基本的に流動性固化材の噴射を停止し、バイブロハンマのみを稼働させて脱気を行う。周波数は同じである。振幅Aは、最大振幅Amax以下で、脱気に必要な最低振幅5mm以上の適切な値に設定する。例えば、偏心モーメントKを最大偏心モーメントKmaxに設定すれば、振幅は8.6mmとなる。このとき、振動加速度ηは、6.1Gとなる。また、脱気時間は、最大30秒とする。
次に、図4を参照して脱気工程を含む鋼杭打設工法を説明する。図4のうち、プロセス(A)~プロセス(G)は、本実施形態に係る鋼杭打設工法による鋼杭打設工法の一例を模式的に示す。
本工法は、移送管3から水を噴射しつつバイブロハンマ2を稼働させることにより鋼杭1を所定深度D4まで貫入する第1工程(図4のうち、プロセス(A)及びプロセス(B))と、鋼杭1の先端部周辺に根固め部を形成するためにバイブロハンマ2を稼働させつつ移送管3から流動性固化材を噴射する第2工程(図4のうち、プロセス(C)~プロセス(E))と、鋼杭1を計画深度(定着深度)D3に位置させて流動性固化材の噴射を停止した後、前記バイブロハンマを一定時間稼働させることにより流動性固化材を脱気する第3工程(図4のうち、プロセス(F))とを有する。
図4のプロセス(A)に示すように、バイブロハンマ2は、鋼杭1の基端部(鉛直方向の打込みの場合は上端部)をチャック装置により把持する。例えば、鋼管杭の円周上縁の2箇所を把持する。バイブロハンマ2は、モータの回転力を一対の偏心重錘にそれぞれ伝達し、それらの偏心重錘を互いに逆回転させることにより一方向の振動を発生する。この振動方向を、打込み方向として使用する。一般的な鋼杭打込用のバイブロハンマの仕様は、例えば、モータ出力90~240kW、周波数11.7~18.3Hz、偏心モーメント420~3600N・m、本体質量7~37tである。但し、本実施形態に係る鋼杭打設工法では、脱気に適切な振幅に設定でき、かつ、振幅可変のバイブロハンマを用いる。
図4のプロセス(C)~プロセス(E)に示す流動性固化材噴射工程の最初に、移送管3へ供給する流体を、水から流動性固化材へ切り替える。そして、バイブロハンマ2を稼働させつつ流動性固化材Cを噴射口3aから噴射し、鋼杭1を所定の範囲で停止又は上下動させる。流動性固化材Cは、例えば圧力15MPa程度以下で噴射する。流動性固化材噴射工程におけるバイブロハンマ2の振幅は、第1工程と同じ第1の振幅とする。この流動性固化材噴射工程においては、第1工程と同じバイブロハンマの振動エネルギーにより、流動性固化材中のセメント粒子が振動することで、ある程度は脱気される。しかしながら、流動性固化材が大量に供給されるため、流動性固化材噴射工程においては十分な脱気を行うことはできない。
ことができる。
図4のプロセス(F)に示す脱気工程では、先ず、計画深度(定着深度)D3に達して打止めした後、計画深度(定着深度)D3の位置で流動性固化材の供給を停止する。流動性固化材については、完全に停止する替わりに、最低必要圧力として極少量の流動性固化材を供給してもよい。これは、噴射ノズルの目詰まりを防止するためである。目詰まり防止のために極少量の流動性固化材のみを供給している状態は、実質的に流動性固化材の供給を停止している状態とみなすこととする。根固め部形成のための供給ではないからである。続いて、バイブロハンマ2の振幅を、脱気に適した第2の振幅に設定してバイブロハンマ2を一定時間、例えば30秒間程度稼働させる。脱気工程におけるバイブロハンマ2の振幅は、5~10mmに設定する。
最後に、図4のプロセス(G)に示す移送管3の引抜工程を行う。先ず、バイブロハンマ2を鋼杭1から取り外す。次に、先端の噴射ノズルとともに移送管3を鋼杭1から離脱させる(移送管3を強制的に引っ張る)。その後、移送管3の上端部をクレーン等(図示せず)で吊り上げつつ、移送管3を引抜く。このとき、噴射口3aから流動性固化材Cを噴射しながら引抜く。これにより、鋼杭1の外側に流動性固化材の固化体である周面固化部C2が形成される。周面固化部C2は、鋼杭1の周面摩擦力を増大させる。そして、噴射口3aが地表近傍に達したところで噴射を停止する。
図5A、図5Bは、本実施形態に係る鋼杭打設工法の施工例1~4における工程管理状況を示した図である。図5Aは、鋼杭先端位置の深度の時間変化を示すグラフである。図5Bは、時間に関する工程管理を示す表である。図示しないが、水又は流動性固化材の流量に関しても工程管理されている。工程管理は、タイマー、圧力計、流量計等により行う。
1a 杭本体
1b 板状リブ突起
1c 線状突起(滑り止め、スリップキーパー)
2 バイブロハンマ
3 移送管
3a 噴出口
4 距離計
W 高圧水
C 流動性固化材
C1 根固め部
C2 周面固化部
Claims (4)
- 鋼杭の長手方向に沿って配設される移送管と、バイブロハンマとを用いて、前記鋼杭を地中に打設する鋼杭打設工法であって、
前記移送管から水を噴射するとともに、前記バイブロハンマを稼働させることにより、前記地中の所定深度に前記鋼杭を貫入する工程と;
前記移送管から流動性固化材を噴射するとともに、前記バイブロハンマを稼働させることにより、前記鋼杭の先端部の周辺に根固め部を形成する工程と;
前記鋼杭を計画深度に位置させて前記流動性固化材の噴射を停止した後、前記バイブロハンマを一定時間稼働させることにより、前記流動性固化材を脱気する工程と;
を有することを特徴とする、鋼杭打設工法。 - 前記鋼杭を貫入する工程及び前記根固め部を形成する工程では、前記バイブロハンマを、貫入のために設定された第1の振幅にて稼動させ、且つ、
前記流動性固化材を脱気する工程では、前記バイブロハンマを、脱気のために設定された第2の振幅にて稼動させる
ことを特徴とする、請求項1に記載の鋼杭打設工法。 - 前記鋼杭が、前記先端部の内面に設けられる線状突起を具備する
ことを特徴とする請求項1又は2に記載の、鋼杭打設工法。 - 前記鋼杭が、前記先端部の外面に設けられる板状リブ突起を具備する
ことを特徴とする請求項1又は2に記載の鋼杭打設工法。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2011237223A AU2011237223B2 (en) | 2010-04-01 | 2011-03-30 | Steel pile driving method involving degasification process |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2010084868A JP5167302B2 (ja) | 2010-04-01 | 2010-04-01 | 脱気工程を含む鋼杭打設工法 |
JP2010-084868 | 2010-04-01 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011125710A1 true WO2011125710A1 (ja) | 2011-10-13 |
Family
ID=44762653
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2011/057966 WO2011125710A1 (ja) | 2010-04-01 | 2011-03-30 | 脱気工程を含む鋼杭打設工法 |
Country Status (4)
Country | Link |
---|---|
JP (1) | JP5167302B2 (ja) |
AU (1) | AU2011237223B2 (ja) |
TW (1) | TWI460337B (ja) |
WO (1) | WO2011125710A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102733379A (zh) * | 2012-05-10 | 2012-10-17 | 王继忠 | 混凝土桩的施工方法 |
CN102733378A (zh) * | 2012-04-25 | 2012-10-17 | 王继忠 | 混凝土桩的施工方法 |
CN102966104A (zh) * | 2012-11-27 | 2013-03-13 | 中国水利水电第七工程局有限公司 | 一种复合锤振动沉管挤密桩工方法 |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5769608B2 (ja) * | 2011-12-06 | 2015-08-26 | 日立造船株式会社 | 鋼板セル・アークの設置工法および鋼板セルの接続部構造 |
JP6093923B2 (ja) * | 2013-06-19 | 2017-03-15 | 新日鐵住金株式会社 | 鋼管杭及び鋼管杭の施工法 |
JP6043378B2 (ja) * | 2015-02-16 | 2016-12-14 | 調和工業株式会社 | 導管引上げ装置及び導管引上げ方法並びに杭の打込み方法 |
JP6630560B2 (ja) * | 2015-12-14 | 2020-01-15 | 東亜建設工業株式会社 | 岩盤への杭打設工法 |
JP6742024B2 (ja) * | 2017-10-20 | 2020-08-19 | 調和工業株式会社 | 杭打設管理システム |
CN115478549B (zh) * | 2022-08-23 | 2023-07-14 | 中交第二航务工程局有限公司 | 一种强透水地层锁扣钢管桩与钢板桩组合围堰施工方法 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63223214A (ja) * | 1987-03-10 | 1988-09-16 | Kobe Steel Ltd | 基礎杭とその築造工法 |
JPH08134892A (ja) * | 1994-11-14 | 1996-05-28 | Nakatomi Kurimoto | 軟弱地盤の改良工法 |
JPH11323903A (ja) * | 1998-05-21 | 1999-11-26 | Ohbayashi Corp | 地盤の液状化対策工法および同対策用固化体 |
JP3850802B2 (ja) * | 2003-03-05 | 2006-11-29 | 新日本製鐵株式会社 | 鋼杭及びその施工方法 |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ATE31334T1 (de) * | 1983-09-19 | 1987-12-15 | Simson & Partner | Vorrichtung zum rammen und ziehen. |
JPH05272137A (ja) * | 1992-03-27 | 1993-10-19 | Kawasaki Steel Corp | 回転貫入鋼管杭の施工方法 |
CN100494581C (zh) * | 2006-09-26 | 2009-06-03 | 华北建设集团有限公司 | 混凝土封底和带桩翼的筒桩成孔器及施工工艺 |
WO2012009756A1 (en) * | 2010-07-19 | 2012-01-26 | Bies David A | Pile driving |
-
2010
- 2010-04-01 JP JP2010084868A patent/JP5167302B2/ja active Active
-
2011
- 2011-03-25 TW TW100110350A patent/TWI460337B/zh not_active IP Right Cessation
- 2011-03-30 WO PCT/JP2011/057966 patent/WO2011125710A1/ja active Application Filing
- 2011-03-30 AU AU2011237223A patent/AU2011237223B2/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63223214A (ja) * | 1987-03-10 | 1988-09-16 | Kobe Steel Ltd | 基礎杭とその築造工法 |
JPH08134892A (ja) * | 1994-11-14 | 1996-05-28 | Nakatomi Kurimoto | 軟弱地盤の改良工法 |
JPH11323903A (ja) * | 1998-05-21 | 1999-11-26 | Ohbayashi Corp | 地盤の液状化対策工法および同対策用固化体 |
JP3850802B2 (ja) * | 2003-03-05 | 2006-11-29 | 新日本製鐵株式会社 | 鋼杭及びその施工方法 |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102733378A (zh) * | 2012-04-25 | 2012-10-17 | 王继忠 | 混凝土桩的施工方法 |
CN102733378B (zh) * | 2012-04-25 | 2013-12-04 | 王继忠 | 混凝土桩的施工方法 |
CN102733379A (zh) * | 2012-05-10 | 2012-10-17 | 王继忠 | 混凝土桩的施工方法 |
CN102733379B (zh) * | 2012-05-10 | 2013-12-04 | 王继忠 | 混凝土桩的施工方法 |
CN102966104A (zh) * | 2012-11-27 | 2013-03-13 | 中国水利水电第七工程局有限公司 | 一种复合锤振动沉管挤密桩工方法 |
Also Published As
Publication number | Publication date |
---|---|
TWI460337B (zh) | 2014-11-11 |
JP5167302B2 (ja) | 2013-03-21 |
TW201139794A (en) | 2011-11-16 |
AU2011237223B2 (en) | 2014-07-31 |
AU2011237223A1 (en) | 2012-10-18 |
JP2011214340A (ja) | 2011-10-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2011125710A1 (ja) | 脱気工程を含む鋼杭打設工法 | |
CN106223331B (zh) | 一种钻进喷射振捣搅拌的施工设备及地基基础的施工方法 | |
CN107417182B (zh) | 膨胀型高聚合物水泥浆、注浆加固装置及注浆加固方法 | |
KR100762991B1 (ko) | 고강도 몰탈을 충진하는 기성말뚝 매입공법 | |
JP3850802B2 (ja) | 鋼杭及びその施工方法 | |
JP2009036010A (ja) | 沈下防止杭の造成方法及び沈下防止杭 | |
JP6535862B2 (ja) | 杭の施工方法 | |
JP6493834B2 (ja) | 地盤の液状化対策工法 | |
JP5808153B2 (ja) | 山留め壁の構築方法 | |
JP2018145089A (ja) | 生コンクリートの気泡の微細化方法 | |
US20200277748A1 (en) | Apparatuses for constructing displacement aggregate piers | |
JP6556485B2 (ja) | 地盤注入方法 | |
KR101657183B1 (ko) | 다짐장치를 활용한 현장 타설 말뚝 공법 | |
CN102966089B (zh) | 一种可以振动密实的插板方法 | |
JP2008144386A (ja) | 地盤改良工法及び地盤改良体 | |
KR101913478B1 (ko) | 진동다짐 및 콘크리트 기둥을 이용한 지반개량공법에 적합한 무근 콘크리트 다짐 장치 및 그 방법 | |
JP5016947B2 (ja) | 固化材振動注入工法及びその装置 | |
JP6546720B2 (ja) | 注入工法を用いた地盤の密実化による液状化対策工法 | |
JP2017179904A (ja) | 構造物の支持構造及び杭基礎構造物の補強方法 | |
JP6876526B2 (ja) | 砂質地盤締固め工法の仕様設定方法 | |
JP2004225453A (ja) | 土木構造物の施工方法 | |
JPS6124718A (ja) | 地盤締め固め装置 | |
JP2016056650A (ja) | 水硬性固化材液置換コラム築造装置、水硬性固化材液置換コラム築造方法および水硬性固化材液置換コラム | |
JP2023038138A (ja) | 砕石杭コンバイン工法 | |
KR20110112937A (ko) | 해상 심층 고화처리 시스템 및 공법 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11765610 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011237223 Country of ref document: AU |
|
WWE | Wipo information: entry into national phase |
Ref document number: 8258/DELNP/2012 Country of ref document: IN |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 2011237223 Country of ref document: AU Date of ref document: 20110330 Kind code of ref document: A |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 11765610 Country of ref document: EP Kind code of ref document: A1 |