JPH07238536A - Building foundation and construction method thereof and construction machine - Google Patents

Abstract

PURPOSE:To construct a foundation with a sufficient strength even in a substandard ground like a soft ground and increase working efficiency and utility efficiency of resources. CONSTITUTION:The-ground 12 where a building 11 is erected is excavated to form a groove 13 corresponding to the building 11. Cement is added to the soil in the groove 13 to compact it to make flat and form a solidified layer 14. Precast concrete foundation blocks 100 are installed on the solidified layer 14 to construct a building foundation 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building foundation, a construction method therefor, and a construction machine for a building foundation used in this method, which can be used for constructing a foundation of a building such as an industrialized house, and particularly using a precast concrete foundation block. It is suitable for cases such as speeding up construction.

[0002]

2. Description of the Related Art Conventionally, in a building such as a house, a foundation is constructed with a lower portion buried in the ground, and a pillar beam or the like as a basic structure is assembled on the foundation. In prefabricated industrial houses, panels and box units are assembled on the same foundation to build a building securely fixed to the ground.

[0003] The foundation of such a building is generally formed by digging a groove in the ground, pouring concrete on site, and filling the lower part after hardening (RC foundation). On the other hand, in industrialized houses and the like, a precast concrete foundation block that has been prefabricated in advance is arranged in a groove and joined to form a foundation (PC foundation). In such a PC foundation, it is not necessary to wait for the concrete hardening time at the site, so that it is possible to reduce the time required for site construction.

Here, in any of the foundations, since a large load of the building is applied to the bottom surface of the groove in which the foundation is installed,
In order to secure the stability of the building, it is necessary to ensure that the load strength at the bottom of the groove is sufficiently obtained (geological problem). In order to solve this problem, in the conventional foundation construction, for example, a procedure as shown in FIG. 8 is adopted (Japanese Patent Laid-Open No. 63-
(See Japanese Patent No. 636861).

First, as shown in FIGS. 8A and 8B, a construction machine 83 (so-called power) equipped with an excavator 82 (narrow bucket, shovel, etc.) suitable for digging a groove at the tip of a movable arm 81. A shovel or backhoe) is carried into the construction site, and a groove 92 corresponding to the foundation is dug in the ground 91 of the site (root cutting process). The excavated earth and sand 93 is piled up in the vicinity.

Next, as shown in FIG. 8C, the trench 92 is filled with the excavated soil 94, and the soil stabilizer 94 and the solidifying agent 95 such as cement are added to the excavated soil 94. (Solidifying agent filling step).
Subsequently, as shown in FIG. 8D, the excavated soil 94 and the solidifying agent 95.
After thoroughly mixing and stirring, and this mixed soil 96
Is temporarily rolled by the excavator 82 of the construction machine 83 (temporary rolling step).

After the temporary rolling pressure is completed, as shown in FIG.
The level between the mixed soil 96 and the current ground 91 is measured, and the operator corrects the place where the level difference is large or the place where the mixed unevenness is present (correction process). Next, as shown in FIGS. 8F and 8G, the mixed soil 96 is subjected to main rolling by the rammer 86, the roller 87, and the like.

After the completion of the main compaction, the level is reconfirmed and water is sprayed on the mixed soil 96 to adjust the water content ratio. This spraying of water is not necessary if the solidifying agent 94 is mixed in an amount of 100 kg or more per square meter. After doing this, the ground improvement is completed by taking a predetermined curing period.

[0009]

By the way, the foundation construction as described above has an advantage that the ground can be improved only at the place where the foundation is arranged. However, since the rammer 86, the roller 87, etc. are used for the construction, the construction is not completed. There is a problem that it is troublesome. Further, in the above-mentioned basic construction, it is necessary to manually adjust the excavated soil 96 and the like, and there is a problem that it is difficult to improve work efficiency (work efficiency problem).

On the other hand, as another method for solving the problem of geology, there is a method of driving piles deep in the ground to secure the strength of the foundation, but a pile driving machine is required, and the construction complexity and construction cost are reduced. There is a problem of leading to an increase. Further, when the foundation 99 is cast in place, the power shovel 83, the concrete pump truck, the crane truck, etc. must be replaced and approached to the portion where the foundation 99 is to be constructed, and in the groove 92 forming the foundation 99. There is a problem that the worker and the rammer 86 and the like need to come in and out in sequence, and the replacement of these is complicated, so that the work efficiency is further reduced due to the interruption of the work (the problem of device replacement).

[0011] A main object of the present invention is to provide a building foundation capable of constructing a foundation having sufficient strength even on poor ground such as soft ground and improving work efficiency, a construction method thereof, and a construction machine. And another object of the present invention is to provide a construction method for a building foundation and a construction machine capable of improving work efficiency in each process, reducing the complexity of device replacement, or improving work continuity. To do.

[0012]

As a result of earnest research on foundation construction and ground adjustment, the present invention can secure strength even if soil with poor geology is solidified by mixing cement. We have come to the knowledge that earth and sand that has been solidified with cement can secure strength equivalent to that of conventional split stones, and that mixing and solidification of earth and sand can be easily performed in foundation construction and it can contribute to process efficiency. It was made based on knowledge.

Specifically, the building foundation of the present invention is constructed by forming a groove excavated in the ground for constructing a building, a solidified layer formed at a bottom portion of the groove with a predetermined thickness, and a solidified layer on the solidified layer. The solidified layer is made of a material that is solidified by adding cement to the earth and sand dug out of the groove. Then, the method for constructing a building foundation of the present invention is to form a groove corresponding to the foundation of the building by excavating the ground for constructing the building, and adding cement to the earth and sand in the groove to flatten and solidify the solidified layer. And forming a foundation of the building on the solidified layer.

To form the groove on the ground, an existing excavating construction machine (such as the above-described power shovel) may be used. At this time, it is desirable that the shovel has a relatively flat lower surface and can be used for compacting earth and sand and cement. The earth and sand generated by digging the groove are left in the groove to be solidified with cement, but may be partially removed according to the required amount.

When adding cement to the earth and sand, the cement may be sprinkled on the earth and sand and then agitated by a shovel or the like. You may let me. Further, if the sand and sand are crushed and then the cement is sprinkled and then stirred, the finely ground soil and sand and the cement are sufficiently mixed, which is suitable for subsequent solidification.

The mixing ratio of earth and sand and cement is appropriately adjusted according to the quality of the earth and sand (water content, sand content, particle size, etc.) so that the desired strength can be obtained when solidified.

According to this structure, a strong layer in which the mixture of earth and sand and cement is solidified is formed on the bottom surface of the groove for installing the foundation, and the desired strength can be obtained without using the split stone. Can be obtained. Further, even when the earth and sand excavated from the ditch has a soft mud quality or the like, by adjusting the mixing ratio of the cement, it is possible to achieve stabilization by ground improvement and form a solidified layer firmly.

Since the solidified layer which is solidified and integrated at the bottom of the groove does not cause a depression like splitting stone, a reliable foundation can be formed even on defective ground. Further, it is possible to eliminate complicated work such as paving of crushed stones, and the earth and sand excavated from the groove is used for forming a solidified layer, so that wasteful disposal can be avoided. Therefore, with such a configuration, it is possible to achieve the above-described main purpose of dealing with soft ground and improving work efficiency.

Here, in forming the above-mentioned groove and solidified layer, first, a groove having a predetermined depth is dug in the ground, the earth and sand in the groove is taken out, cement is sprinkled on the earth and sand, and the mixture is stirred and kneaded. The mixture of the kneaded cement and earth and sand may be returned to the groove and tamped to form a solidified layer. By doing this, it is possible to perform easy kneading by existing work outside the groove, and adjust the thickness of the solidified layer formed in the groove by adjusting the amount of cement-sand mixture mixed into the groove. You can also

Further, first, a groove having a predetermined depth is excavated in the ground, cement is sprinkled on the earth and sand excavated during the excavation, and the mixture is agitated and kneaded simultaneously with the excavation, and kneaded in the groove. The solidified layer can be formed by compacting a mixture of cement and earth and sand. In this way, since the cement and the earth and sand can be mixed in the groove, the work of carrying the earth and sand out of the groove can be omitted, and the work can be simplified and made more efficient.

Further, first, a groove having a predetermined depth is dug in the ground, the earth and sand in the groove is taken out, and then cement is sprinkled on the bottom surface, and then the bottom surface on which the cement is sprinkled is further excavated and stirred. The mixture of cement and earth and sand generated in the groove can be tamped to form a solidified layer. By doing so, the soil and the cement are mixed at the same time during the second excavation, the work efficiency in this process is improved, and the sediment due to the second excavation is solidified together with the cement. The amount of earth and sand mixed in the solidified layer can be adjusted easily and reliably by the depth, and in this respect also, the working efficiency can be improved.

Further, the construction method of the building foundation of the present invention is
In spraying the cement, the bag filled with the cement is lifted up, the lower end portion is cut open, and the cement inside is dropped to be put into the groove. With this configuration, it is possible to spray directly from the cement bag, which usually has a considerable weight, into the groove, and it is possible to efficiently perform the cement spraying process to the soil in the groove, and to improve work efficiency in this respect as well. Is possible.

In the case of moving and spraying, it is desirable to appropriately adjust the size of the cut-opening of the bag so that the spraying amount per time is in accordance with the moving speed.

And, the construction method of the building foundation of the present invention is as follows:
It is characterized in that a precast concrete foundation block is used for the foundation, and the lower portion of the constructed foundation is filled with earth or sand or concrete. As the precast concrete foundation block, it is possible to use one having a cloth foundation-like cross section having a rising portion on a flat leg portion, one having only a rising portion, a rectangular block forming an independent foundation, or the like.

According to this structure, the foundation can be formed only by arranging the preformed foundation blocks, and it is not necessary to cast the foundation in-situ. Therefore, the steps after the solidified layer is compacted can be efficiently performed. As a result, it becomes possible to improve the work efficiency of the foundation construction as a whole.

Further, the method for constructing a building foundation according to the present invention is characterized in that the step of excavating the groove, the step of adding the cement, and the step of compacting are performed using the same construction machine. As a construction machine that can execute each step, for example, the above-described power shovel or the like can be used, and after excavating with a shovel, suspending a bag of cement at the tip of the excavator and then spraying the cement, and thereafter The bottom surface may be tapped with a mixture of earth and sand and crushed.

At this time, the sand and the cement may be agitated and mixed with a shovel between the spraying and the compacting of the cement. Alternatively, a roller-shaped or impeller-shaped stirrer may be installed in a vehicle body such as a power shovel and stirring may be performed by this. With this configuration, it is possible to simplify or omit the replacement of the construction machine used in each step of the basic construction, and it is possible to eliminate the complexity of the conventional replacement and improve the work efficiency. Become.

Further, the construction method of the building foundation of the present invention is as follows:
A mechanism for processing the steps is installed in the construction machine, the construction machine is run along the ground on which the foundation of the building is to be installed, and the steps are continuously performed during the running. Is characterized by. As a mechanism for processing each process, an existing mechanism that can be used for each process may be used.
A mechanism used in another step may be used. For example, a mechanism for excavating the above-mentioned shovel, a mechanism for spraying cement (utilizing a dedicated hopper or excavator), a mechanism for agitating earth and sand (utilizing a dedicated agitator or excavator), earth and sand and cement It is only necessary to have a mechanism for compacting (such as a dedicated press device or diversion of the lower surface of the excavator), and if these are equipped integrally with a crawler (endless track) or wheels and capable of running Good.

If each mechanism is arranged on the vehicle body or the like in the order of steps, it is possible to excavate or tamper with a single movement. However, the order is not limited to this order, and in that case, continuous processing may be performed by moving along the groove several times. According to this structure, each step of the basic construction can be continuously executed, no wasteful time is generated between the steps, and the work efficiency can be further improved.

On the other hand, the building foundation construction machine of the present invention is a building foundation construction machine used in the above-mentioned building foundation construction method, and has a vehicle body capable of traveling on the ground. An excavating means for excavating a groove in the ground, a stirring means for stirring the earth and sand in the excavated groove, a spraying means for spraying cement in the groove, and a pressing means for compacting the earth and sand in the groove. It is characterized by being

As the vehicle body, a vehicle body similar to an existing construction machine can be used, and any vehicle can be used as long as it can be equipped with crawlers (tracks) or wheels. The excavating means is an excavating mechanism such as a shovel or a belt cutter, and the agitating means is a dedicated stirrer (plow-shaped or rotary impeller type).
Alternatively, as a diversion or pressing means for a shovel or the like, a dedicated pressing device (a flat lower surface that can be pressed by hydraulic pressure, a material that can be further pressed by vibration, etc.) or a diversion of the lower surface of the shovel can be used.

According to this structure, each step of the above-mentioned foundation construction method can be processed by one unit, and the complexity and wasteful time for replacing the conventional construction machine can be eliminated. Work efficiency can be improved.

Further, the building foundation construction machine of the present invention is
The vehicle body is further provided with a ground strength measuring means for measuring the ground strength of the bottom surface in the groove compacted by the pressing means, and a suspending means for suspending and carrying in a precast concrete foundation block from the outside on the bottom surface in the groove. And means are installed. Here, as the ground resistance measuring means, existing instruments for measuring the hardness of the ground can be used, for example, those for measuring the resistance force when inserting a rod-shaped member into the ground can be used, and as the suspending means. The existing boom type crane may be used as appropriate. is there.

With this structure, it is possible to measure the ground yield strength after the above-mentioned excavation, stirring, and pressing to confirm whether the solidified layer has sufficient strength. It is also possible to continuously perform the work of suspending and installing the foundation block foundation, which can further improve the work efficiency.

[0035]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention. In FIG. 1, a building foundation 10 constructed according to the present embodiment has a lower portion embedded in a ground 12 for constructing a building 11 and fixedly supports the building 11.

The building foundation 10 is formed by connecting a plurality of foundation blocks 100 made of precast concrete. Each base block 100 has a leg portion 101 that spreads horizontally in the lower portion, and has an inverted T-shaped cross section in which a rising portion 102 is vertically connected to the center of the upper surface thereof, and is continuous over a predetermined length in the direction orthogonal to FIG. It is a thing. Adjacent ones of these foundation blocks 100 are joined to each other and integrated to form the building foundation 10. For mutual joining, bolts and nuts that connect the reinforcing bars to each other or cement that fixes the surfaces of the two are used.

The building foundation 10 is embedded in the ground 12 so that the entire leg portion 101 of the foundation block 100 and the lower portion of the rising portion 102 are embedded. To this end, the ground 1
A groove 13 is formed on the base 2 according to the installation position of the building foundation 10, and a leg portion 101 is placed on the bottom of the groove 13 to solidify the layer 1.
4 is formed, and a filling layer 15 is formed above the solidified layer 14 and the leg portion 101 and on both side surfaces of the rising portion 102 so as to be buried in the upper portion of the groove 13.

The solidified layer 14 is a layer in which cement is mixed with the earth and sand produced when the groove 13 is dug, and the cement 13 is solidified at the bottom of the groove 13 to flatten the upper surface. At this time, it is desirable to appropriately stir so that the earth and sand and the cement are sufficiently mixed. Further, the earth and sand may be pulverized or the like before mixing with the cement depending on its quality, particle size and the like, or may be adjusted by drying or adding water so that the water content is suitable for hardening the cement. Then, it is desirable that the building foundation 10 be tamped so as to have a sufficient solidification strength to receive the building foundation 10.

As for the filling layer 15, of the earth and sand generated when the trench 13 is dug, except for the amount used for the solidification layer 14, is taken out around the trench 13 and the solidification layer 14 and the basic block 100 are installed. It is formed by backfilling the removed soil. The filling layer 15 may be only earth and sand, or may be cement mixed and solidified. Further, the solidified layer 15 is thinly spread over the entire lower surface of the building 11. The portion may be concrete or the like.

The dimensions of the above-mentioned building foundation 10 are as follows: depth 600 mm, bottom width 600 mm, solidified layer 14 thickness 300 m.
m, thickness 50 of the lower part of the building 11 (outside the groove 13) of the packed bed 15
It is about mm. When the solidified layer 14 having such a thickness is formed, there is almost no surplus of earth and sand excavated from the groove 13 except for the amount used for the filling layer 15.

In constructing the building foundation 10 as described above, a construction machine as shown in FIG. 2 is used. In FIG. 2, the construction machine 20 is equipped with crawlers 210 (endless track, trademark caterpillar, etc.) on both sides and a vehicle body 21 capable of traveling on rough terrain. Note that wheels may be used instead of crawlers for traveling.

A narrow excavator 22 (excavating means) suitable for excavating the groove 13 and a stirring roller 23 (stirring means) suitable for stirring earth and sand in the groove 13 are installed at one end of the vehicle body 21. ing. A cockpit 24 and a crane 25 (suspending means) are installed near the same side end of the vehicle body 21. Further, the cement hopper 2 is provided in the middle of the vehicle body 21.
6 (spraying means), pressing means 27, ground strength measuring means 28
Is installed. Also, at the other end of the vehicle body 21,
A blade 29 for collecting earth and sand while leveling the ground 12 (which is installed in a so-called bulldozer; ground leveling means and earth and sand sweeping means) is installed.

The shovel 22 is supported by the vehicle body 21 via an arm 220. The arm 220 is rotatably supported by the vehicle body and driven by a drive mechanism 221 such as a hydraulic cylinder to move up and down on the tip side. The shovel 22 is rotatably supported by the tip of the arm 220, and has a drive mechanism 222 such as a hydraulic cylinder.
With this, the groove 13 can be excavated in the ground 12.

The agitating roller 23 is for agitating earth and sand and the like on the peripheral surface by rotation, and may have any existing shape that is good for catching earth and sand on the peripheral surface. For example, a rod or the like may be combined to form a cylindrical cage. What is formed, or what was formed in a roll brush shape by implanting many protrusions on the peripheral surface of the cylindrical core is used. The stirring roller 23 is an arm 230
It is supported by the vehicle body 21 via. The arm 230 is rotatably supported by the vehicle body and driven by a drive mechanism 231 such as a hydraulic cylinder to move up and down on the tip side. Thereby, the stirring roller 23 can be retracted above the ground 12 and can be introduced into the groove 13. The stirring roller 23 is driven to rotate by the vehicle body 2.
1 is provided by a hydraulic drive device or the like (not shown).

The crane 25 has an arm 250 that extends obliquely upward from the one side of the vehicle body 21 to the other side, and an extendable extension portion 251 is provided at the tip of the arm 250. Free wire 252 for hook 25
3 is suspended. The extension portion 251 is driven to expand and contract to an appropriate length by driving means such as a built-in hydraulic cylinder. The wire 252 can be raised and lowered by winding it up with a winch (not shown) and pulling it out. As a result, it is possible to lift the foundation blocks 100 stacked on the surrounding ground 12 or the truck bed and hang it down to another arbitrary position.

Telescopic rods 254 and 25, which extend and contract with a hydraulic cylinder as an auxiliary load receiving mechanism between the arm 250 and the extension 251 respectively, are connected to the vehicle body 21.
5 are installed. Of these, the telescopic rod 254 is simultaneously expanded and contracted when raising and lowering the tip of the arm 250, and the telescopic rod 255 is simultaneously expanded and contracted as the tip of the arm 250 is moved up and down and the extension portion 251 is extended and contracted, and the downward load of each tip is shared. The weight of the basic block 100 that is loaded and hung on the hook 253 can be sufficiently endured. The ends of the rods 254 and 255 are pivotally connected to perform the above-described operation.

The cement hopper 26 stores the cement powder replenished from the upper part, collects it in a funnel-shaped part, and sprays it from below. A stirring mechanism 260 such as an impeller is installed at the spraying outlet part. When sprayed, the aggregate of cement powder is crushed so that fine powdery cement can be uniformly sprayed over a wide range. The pressing means 27 is the vehicle body 2
A press board 270 having a flat lower surface is provided on the lower surface side of 1 and the press board 270 is driven up and down below the vehicle body 21 by driving means such as a hydraulic device (not shown) to press and solidify the earth and sand in the groove 13 of the ground 12. It is possible. It should be noted that as the pressing means 27, a vibrating means for applying vibration to the press board 270 (an existing excitation method such as an air reciprocating piston or a rotating eccentric weight type may be used) may be added.

The ground strength measuring means 28 is an existing measuring instrument for measuring the hardness of the ground, and here, a measuring rod 280 extending below the vehicle body 21 and the measuring rod 280 is moved downward and forward. A drive mechanism 281 such as a hydraulic cylinder, and an operating load of the drive mechanism 281 are detected to measure the rod 28 for measurement.
0 measures the hardness of the ground from the resistance when it stabs into the ground, and the measuring means (not shown) that measures the resistance force when inserting 0 into the ground. The measuring rod 280 can reach the inside of the solidified layer 14 in the groove 13.

The blade 29 is supported by the vehicle body 21 via the arm 290. The arm 290 is rotatably supported by the vehicle body and driven by a drive mechanism 291 such as a hydraulic cylinder to move up and down on the tip side. As a result, when the vehicle body 21 is run with the blade 29 lowered and along the ground 12, it is possible to level the surface of the ground 12 and scrape off excess soil and the like.

Next, a procedure for constructing the building foundation 10 using the construction machine 20 as described above will be described with reference to FIGS. 3 and 4. First, as shown in FIG. 3A, the construction machine 20 is guided to the construction position of the building foundation 10 on the ground 12, and the construction machine 20 is run in the direction of the groove 13 while excavating the groove 13 using the shovel 22. Then, the continuous groove 13 is formed. At this time, the excavated earth and sand is left in the groove 13.

Then, as shown in FIG. 3 (B), when the agitating roller 23 approaches the groove 13 along with traveling, the agitating roller 23 at the rear of the traveling direction is lowered to agitate the earth and sand dug out in the groove 13. . In addition, the cement hopper 26 has a groove 13
When approaching, this hopper 26 is operated and the cement is sprinkled on the agitated earth and sand in the groove 13. Similarly, when the pressing means 27 reaches the groove 13, the pressing means 27 is lowered, and the earth and sand in the groove 13 in which the cement has been sprayed is compacted. Thus, as shown in FIG. 3C, when the groove 13 is excavated to a predetermined end position, the shovel 22, the stirring roller 23, the cement hopper 2 are arranged in the order in which the end position is reached.
6. The operation of the pressing means 27 is stopped and the groove 13 is appropriately pulled up. As a result, the solidified layer 14 is formed in the groove 13 over the entire length by solidifying the sand and cement.

Next, as shown in FIG. 4A, the construction machine 20
Run in the direction opposite to the previous one, and
When it reaches the groove 13, it is lowered and the hardness of the solidified layer 14 is inspected. Then, if the hardness is insufficient, the pressing means 27, which is at the rear of the traveling direction, additionally performs tamping. During this time, it is possible to repeat the procedure of returning to ground strength and measuring and tamping as needed. As a result, the solidified layer 14 has a required hardness.

Then, as shown in FIG. 4B, when returning to the end of the groove 13 on the digging side, a truck or the like having the basic block 100 loaded thereon is brought close to the construction machine 20 to move the basic block 100 on the bed. Lift with crane 25. Specifically, the extension part 251 of the crane 25 is extended (the telescopic rod 255 also extends), the wire 104 hung on the basic block 100 is hooked on the hook 253, and the arm 250 is raised while winding the wire 252 (the telescopic rod 254, 255 is also extended), and the basic block 100 is lifted. Then, the suspended basic block 100 is arranged above the groove 13, and the wire 252 is unwound while lowering the arm 250, and the basic block 100 is placed on the solidified layer 14.
To place.

After the base block 100 is installed on the solidified layer 14 from one end to the other end in this way, the groove 13 is filled with earth and sand so as to cover the solidified layer 14 and the lower part of the basic block 100. For this work, the blade 2 of the construction machine 20
9 may be used. From the above, the building foundation for one section 1
The construction of No. 0 is completed, the same construction is continuously performed on the adjacent ground 12, and when all the sections are completed, the building foundation 10 is completed.

According to this embodiment, the following effects can be obtained. First, on the bottom surface of the groove 13 in which the building foundation 10 is installed, a strong solidified layer 14 obtained by tamping a mixture of earth and sand and cement can be formed. Therefore, it is possible to obtain a desired strength without using a conventional split stone. Due to this, the conventional problems associated with the use of split stones (geological problems, work efficiency problems, material use efficiency problems)
Can be solved.

In particular, since the solidified layer 14 is obtained by adding cement to the earth and sand in the groove 13 and solidifying it, the solidified layer 14 is solidified at the bottom of the groove 13 and becomes an integral body, and does not cause a sink like the conventional split stone. Therefore, the reliable building foundation 10 can be formed even on the bad ground. Further, even when the earth and sand dug out of the groove 13 is a soft mud or the like, a strong solidified layer can be formed by adjusting the mixing ratio of cement.

With these, it is possible to solve geological problems such as defective ground.

Furthermore, by not using the conventional split stones, it is possible to solve the complicated work such as the spreading of the split stones and to solve the problem of work efficiency. And the solidified layer 1
4 uses the earth and sand excavated from the groove 13 and also backfills for fixing the building foundation 10,
Most of the earth and sand excavated from 3 can be used for the building foundation 10, and need not be wastefully discarded. In this way, the earth and sand dug in the groove 13 can be effectively reused, and it is not necessary to use a separate split stone, so that the problem of material utilization efficiency can be solved.

Next, in this embodiment, since the foundation blocks 100 made of precast concrete are arranged to form the foundation, it is not necessary to cast the foundation on site. For this reason,
The process after the compaction of the solidified layer 14 can be efficiently performed, and the work efficiency as a whole foundation construction can be improved. In addition, in this embodiment, each step of foundation construction (excavation,
Stirring, cement spraying, press tamping, ground bearing measurement, foundation block installation) can be performed by one construction machine 20, and construction machines such as when using various construction machines like conventional foundation construction. Can be eliminated, eliminating the complexity of such machine replacement,
Work efficiency can be improved.

Further, in the present embodiment, each step of the foundation construction described above can be continuously executed by the construction machine 20, and no wasteful time is generated between the steps,
Work efficiency can be further improved. In particular, the steps of excavation, stirring, cement spraying, and press compaction can be carried out simultaneously in one run, and the working time can be further shortened.

Further, in this embodiment, the additional tamping can be performed while the ground strength of the solidified layer 14 is being measured, and the strength of the solidified layer 14 and thus the building foundation 10 can be ensured.

Further, in the construction machine 20 of this embodiment, since the crane 25 is reinforced by the telescopic rods 254 and 255, even the heavy foundation block 100 can be reliably lifted. The construction machine 20 of the present embodiment can be configured by using the vehicle body 21 of the existing construction machine and each mechanism, and can be easily implemented.

In the first embodiment, the construction machine 20
In the first run, each step of excavation or press tamping is executed, in the second reverse run ground resistance measurement and additional tamping are performed, and the foundation block 100 is installed in the third run However, all of these steps may be performed in one run. In this way, there is no need to fold back at the end, and it is possible to perform construction with even higher continuity.

Further, in the first time, excavation, agitation, and reverse second
It may be possible to perform cement spraying and re-mixing at once, and tamping and ground resistance measurement and foundation block installation at the third time, etc. By doing this, mixing of cement and soil improves by re-mixing after spraying cement. Therefore, the strength of the solidified layer 14 can be increased.

However, even in the case of spraying after stirring as in the above-mentioned embodiment, since the sprayed cement enters into the gap between the earth and sand, the strength of the solidified layer 14 can be sufficiently obtained, and the soil proof stress and additional tamping can be performed. By securing the strength of the solidified layer 14 and then installing the foundation block 100, the foundation strength is ensured reliably, and therefore the procedure as in the first embodiment is most suitable.

In the first embodiment, the construction machine 20
Although a means for executing all the steps from excavation to installation of a foundation block is provided in the above, a part of the means may be omitted and a separate machine may be brought in for substitution. For example, the crane 25 of the construction machine 20 may be omitted, and the foundation block 100 may be installed by another mobile crane. Since this process is the last of foundation construction, construction machine 2
It is only necessary to introduce 0 after moving 0 to another position, and the problem of machine replacement does not occur.

Further, the earth proof strength measuring means 28 may be omitted, and this step can be easily performed by an inspection by a worker, and the workability is not particularly lowered.

A second embodiment of the present invention is shown in FIGS. As shown in FIG. 5, in the present embodiment, as in the first embodiment, the lower part is embedded in the ground 12 and the building 11 is installed.
The building foundation 30 which fixedly supports is constructed.
In the building foundation 30 of the present embodiment, the same foundation block 100 as in the first embodiment is used, and the groove 33 is dug and buried in the ground. The shapes of the groove 33 and the solidified layer 34, the construction machine 40 to be used, and the construction. The procedure is different from that of the first embodiment.

In the groove 33 of this embodiment, the solidified layer 34 portion is narrower than the upper portion and formed in a step shape. That is, the groove 33 is the first groove 33 of 200 to 300 mm on the ground 12.
After digging 1 (bottom width 700mm), 200-300m on the bottom
It is formed by digging the second groove 332 (bottom width: 500 mm) of m 2. The solidified layer 34 is formed in the second groove 332.

As shown in FIGS. 6 (A) and 6 (C), the construction machine 40 of this embodiment has an excavating and stirring roller added to an existing power shovel or the like. In particular,
The construction machine 40 has a rotatable pedestal 403 on a trolley 402 that can be driven by the crawlers 401 on both sides, and a cockpit 404 and a shovel arm 405 are installed on the rotary pedestal 403.

The shovel arm 405 is pivotally supported at its base end and can be swung so as to move up and down on the tip side by a driving means 406 such as a hydraulic cylinder.
7 can also be bent and swung by drive means 408 such as a hydraulic cylinder. A shovel 409 is pivotally connected to the shovel arm 405, and the shovel 409 can be swung by a driving means 410 such as a hydraulic cylinder. The shovel 409 can form a first groove 331 on the ground 12 (excavation means).

The excavation stirring roller 41 is provided at the rear end of the carriage 402.
1 is installed. The excavation stirring roller 411 stirs the earth and sand excavated while excavating the ground on the peripheral surface by rotation (also serves as excavation means and stirring means).
The existing shape is adopted because it strongly traps the soil on the circumference. For example, a rod-shaped member or the like that is formed into a cylindrical cage and has an excavation protrusion on its peripheral surface, or one in which a large number of protrusions are planted on the peripheral surface of a cylindrical core is used.

The excavation stirring roller 411 is supported by the carriage 402 via an arm 412. The arm 412 is rotatably supported by the vehicle body and driven by a drive mechanism 413 such as a hydraulic cylinder to move up and down on the tip side. Excavation stirring roller 41
The rotary drive of No. 1 is performed by a hydraulic drive device or the like (not shown) provided on the carriage 402. Excavation stirring roller 411
Is normally held above, but by lowering it downward and rotating it, the second groove 332 is formed on the bottom surface of the first groove 331.
Can be formed (see FIG. 6C).

Next, the procedure for constructing the building foundation 30 using the construction machine 40 as described above will be described with reference to FIGS. 6 and 7. First, as shown in FIG. 6 (A), the construction machine 40 is guided to the construction position of the building foundation 10 on the ground 12, and the excavator 409 is used to excavate the first groove 331. At this time, the excavated earth and sand is taken out from the groove 331 and piled up on the ground 12 in the vicinity (embankment 121). By moving sequentially while excavating, building foundation 4
A series of grooves 331 corresponding to 0 is formed.

Next, as shown in FIG. 6B, the shovel 40
The cement bag 420 is hung on the tip of 9 through a wire or the like, held on the first groove 311 and the lower part thereof is cut open to spread the cement 421. The cement 421 is spread over the entire bottom surface of the first groove 311 by sequentially moving while performing the cement spraying. Then, in FIG.
As shown in (C), the rotary pedestal 403 is swung to orient the shovel arm 405 laterally to ensure a front and rear view, and the construction machine 40 is guided so as to straddle the first groove 331 and rearward. The digging and stirring roller 411 is introduced into the first groove 331, and the second groove 332 is digged on the bottom surface of the groove 331. Due to this excavation, the excavated earth and sand 122 is the cement 42 that was previously scattered on the bottom surface of the first groove 331.
1 and mixed and stirred.

While performing this mixing and stirring, the first groove 331
By sequentially moving the construction machine 40 along the
As shown in FIG. 6 (D), a second groove 332 is formed on the bottom surface of the first groove 331 over the entire length thereof.
3 is formed. At this time, the second groove 332 is partially filled with the cement-mixed earth / sand 122 that has risen up to the inside of the first groove 331. The swelling of the earth and sand 122 is mainly due to an increase in the gap between the earth and sand due to the mixing and stirring.

Next, as shown in FIG. 7A, the construction machine 40
Is guided to one end of the groove 33, the shovel 409 is guided into the groove 33, and the cement-containing earth and sand 122 in the groove 33 is guided on the lower surface thereof.
Tamper with. As the construction machine 40 is sequentially moved along the groove 33 while performing the tamping, the solidified layer 34 filled and solidified in the second groove 332 is filled in the groove 33 as shown in FIG. 7B. Is formed.

Then, the base block 100 is placed on the upper surface of the solidified layer 34 by another crane vehicle or the like, and the earth and sand previously set as the embankment 121 is backfilled.
A building foundation 30 as shown in FIG. 5 is formed.

According to this embodiment, the following effects can be obtained. That is, the groove 33 for installing the building foundation 30
A strong solidified layer 34 obtained by tamping a mixture of earth and sand and cement can be formed on the bottom surface of the. For this reason, it is possible to obtain the desired strength without using the conventional crushed stone, and to solve the conventional problems (geological problems, work efficiency problems, material utilization efficiency problems) associated with the use of crushed stones. It can be solved (see the first embodiment).

Also, in this embodiment, since the precast concrete foundation block 100 is used, as in the case of the first embodiment, it is possible to eliminate the need for in-situ casting of the foundation and improve the work efficiency of the entire foundation construction. be able to.

On the other hand, in this embodiment, each step of foundation construction (excavation of the first groove 331, spraying of cement, second groove 332).
(Excavation, stirring, and compaction) can be performed by one construction machine 40, and then the foundation block 100 can be hung by a crane vehicle or the like, so that various constructions such as conventional foundation construction can be performed. It is possible to eliminate the replacement of the construction machine as in the case of using the machine, eliminate the complexity of such machine replacement, and improve the work efficiency.

The present invention is not limited to the above embodiments, and the present invention also includes the following modifications and the like. That is, as the cement used in the present invention, various existing cements may be used, and the mixing ratio thereof may be adjusted according to the water content or hardness of the earth and sand excavated from the groove.

The dimensions of the groove are not limited to those in each of the above-mentioned embodiments, and may be appropriately selected for implementation. For example, when more stability is required on soft ground, adjustments such as increasing the groove width to increase the bottom area of the solidified layer may be performed.

Further, as in the first and second embodiments, the cement mixing is not performed at the same time as the excavation of the groove, but the earth and sand may be taken out after the excavation, the cement may be mixed outside the groove and then returned to the inside of the groove. However, if this is done, it is possible to easily prepare a sufficient amount of earth and sand for the solidified layer by adjusting the amount of earth and sand mixed with cement, and when returning the mixture of cement and earth and sand into the groove. Since the amount can be adjusted, the thickness of the solidified layer can be easily adjusted.

Further, in the first embodiment, the earth and sand excavated from the groove 13 is backfilled to form the filling layer 15, but cement may be mixed outside the groove 13 and solidified in the same manner as the solidified layer 14. This way, a strong foundation can be fixed. Alternatively, the solidified layer 14 may also be mixed with cement outside the groove 13.

Further, the construction machine used in the present invention is not limited to the foundation construction-dedicated machine provided with all the mechanisms corresponding to the respective steps of the foundation construction as in the first embodiment, but the second construction machine described above.
As in the embodiment, some steps such as ground bearing measurement may be performed manually. Further, as in the second embodiment,
The construction machine may be a general-purpose machine or the like in which a mechanism for excavation and stirring is added to an existing power shovel, and for example, a so-called stabilizer for excavation and stirring is appropriately provided with cement spraying means, pressing means such as press or stamper, etc. You may add and use it.

Means for executing each of these steps may be appropriately selected and used from the existing equipment and devices as long as each function can be secured.

The foundation to which the present invention is applied is not limited to the continuous foundation made of precast concrete and having an inverted T-shaped cross section (general cloth foundation) as in the above-mentioned embodiments. That is, the horizontal leg portion of the lower portion of the foundation and the vertical rising portion of the upper portion may be provided as separate precast blocks and joined at the time of site installation. Alternatively, it may be formed in an inverted T-shape in cross section by using cast-in-place concrete. However, if the reverse T-type precast block foundation as described above is used, the on-site construction can be performed most efficiently.

Further, the shape is not limited to the inverted T shape, but may be a substantially I shape in which the legs are omitted, or a substantially inverted Y shape in which the rising portion gently expands. Further, each basic block is not limited to a continuous foundation, but may be an independent foundation that is partially independent. However, continuous foundations are often used in general buildings. In addition, the plane shape of the foundation formed on the ground may be set appropriately according to the building constructed on the upper part, and the building constructed on the upper part is a prefabricated type (box type unit type) for houses and apartments. , Panel type, framed panel type, etc.) or various buildings by conventional construction method can be arbitrarily selected.

[0090]

As described above, according to the present invention,
By mixing cement with the earth and sand in the excavated ditch to form a solidified layer, the strength can be ensured even for defective ground such as softness. In addition, it is possible to eliminate the complexity of construction such as the foundation of the conventional split stone method, and improve the work efficiency. Furthermore, the excavated earth and sand can be effectively used, and the material utilization efficiency can be improved.

In particular, the excavation of the trench is performed in two steps, the sediment from the first trench is carried out, and the solidified layer is formed from the sediment from the second trench, so that the amount of the sediment to be taken out can be adjusted or the solidified layer can be used. The amount of sediment used can be adjusted easily and reliably. Furthermore, the cement spraying operation can be easily performed by suspending the cement bag and opening the lower end to add the cement inside.

Further, by using the precast concrete foundation block, on-site construction can be greatly simplified and the foundation construction period can be shortened.

Further, by making it possible to perform each process such as excavation of a groove, spraying of cement, and compaction with the same machine, it is possible to eliminate the complexity of machine replacement such as the conventional foundation construction. In particular, by performing the processing of each step continuously while running the construction machine equipped with each means for executing each step, it is possible to significantly improve the work efficiency as compared with the case of sequentially performing each step.

Then, the construction machine equipped with the excavating means, the agitating means, the cement spraying means, and the pressing means for compacting is used to continuously process the series of steps of the foundation construction described above by the same machine. Therefore, it is possible to reliably promote improvement in work efficiency including elimination of machine replacement. Also, by installing ground strength measuring means and suspending means in parallel with this construction machine, the same machine can be used to inspect the solidified layer and carry in the precast concrete foundation block, and work efficiency including elimination of machine replacement can be achieved. Can be further promoted.

[Brief description of drawings]

FIG. 1 is a sectional view showing a basic structure of a first embodiment of the present invention.

FIG. 2 is a schematic side view showing the construction machine of the first embodiment.

FIG. 3 is a schematic view showing the first half of the process of foundation construction of the first embodiment.

FIG. 4 is a schematic view showing the latter half of the process of foundation construction of the first embodiment.

FIG. 5 is a sectional view showing a basic structure of a second embodiment of the present invention.

FIG. 6 is a schematic diagram showing a first half of a process of foundation construction of the second embodiment.

FIG. 7 is a schematic diagram showing the latter half of the steps of the foundation construction of the second embodiment.

FIG. 8 is a sectional view showing a modified example of the present invention.

FIG. 9 is a schematic view showing a conventional foundation construction.

[Explanation of symbols]

10 Building Foundation 100 Precast Concrete Foundation Block 11 Building 12 Ground 13 Groove 14 Solidification Layer 15 Packing Layer 20 Construction Machinery 21 Car Body 22 Excavator Excavator 23 Stirring Roller 25 Stirring Crane 26 Spraying Means Cement hopper 27 Pressing means 28 Ground strength measuring means 29 Blades which are means for collecting and collecting sand and leveling ground 30 Building foundation 33 Grooves 331 Grooves 331 First grooves 332 Second grooves 34 Solidified layer 40 Construction machinery 402 Truck 405 Excavation Excavator arm 409 which is means Excavator 411 which is excavating means Excavation stirring roller which doubles as excavation means and stirring means

Claims (11)

[Claims] 1. A solidification layer comprising a groove formed by excavation on the ground for constructing a building, a solidification layer formed at a bottom portion of the groove with a predetermined thickness, and a foundation constructed on the solidification layer. Is a building foundation made of a material obtained by adding cement to the earth and sand excavated from the trench and solidifying the cement. 2. The ground for constructing a building is excavated to form a groove corresponding to the foundation of the building, cement is added to the earth and sand in the groove to flatten and solidify to form a solidified layer, and the solidified layer A method for constructing a building foundation, characterized by constructing the foundation of the building on a building. 3. The method for constructing a building foundation according to claim 2, wherein a groove having a predetermined depth is first dug in the ground, the earth and sand in the groove is taken out, and the earth and sand is sprayed with cement and stirred and kneaded. A method for constructing a building foundation, which comprises returning the mixture of the kneaded cement and earth and sand to the groove and then compacting it to form a solidified layer. 4. The method for constructing a building foundation according to claim 2, wherein a groove having a predetermined depth is first excavated in the ground, and cement is sprinkled on the earth and sand excavated during the excavation. A method for constructing a building foundation, which comprises simultaneously stirring and kneading and solidifying a mixture of cement and earth and sand mixed in the groove to form a solidified layer. 5. The method for constructing a building foundation according to claim 2, wherein a groove having a predetermined depth is first dug in the ground, the earth and sand in the groove is taken out, and then a cement is sprayed on the bottom surface. The method for constructing a building foundation, comprising: excavating the bottom surface, on which the powder has been dispersed, while further deeply excavating, and agitating the mixture of cement and earth and sand generated in the groove to form a solidified layer. 6. The method for constructing a building foundation according to any one of claims 2 to 5, wherein when the cement is sprayed, the bag filled with the cement is lifted up and a lower end portion of the bag is cut open. A method for constructing a building foundation, characterized in that the cement described in 1. is dropped and placed in the groove. 7. The method for constructing a building foundation according to any one of claims 2 to 6, wherein a precast concrete foundation block is used as the foundation, and the lower portion of the constructed foundation is solidified with earth or sand or concrete. Construction method of building foundation characterized by. 8. The method for constructing a building foundation according to claim 2, wherein the step of excavating the groove, the step of adding the cement, and the step of compacting are performed using the same construction machine. A method of constructing a building foundation, which is characterized by that. 9. The method for constructing a building foundation according to claim 8, wherein the construction machine is provided with a mechanism for treating each of the steps, and the construction machine is installed along the ground on which the foundation of the building is to be installed. A method for constructing a building foundation, characterized in that the above steps are continuously performed during the traveling. 10. A construction machine for a building foundation used in the method for constructing a building foundation according to any one of claims 2 to 9, comprising a vehicle body capable of traveling on the ground, An excavation means for excavating a groove in the ground, a stirring means for agitating earth and sand in the excavated groove, a spraying means for disperse cement in the groove, and a pressing means for compacting the earth and sand in the groove. A construction machine for building foundations that is characterized by 11. The construction machine for building foundation according to claim 10, wherein the vehicle body further includes a ground strength measuring means for measuring a ground strength of a bottom surface in the groove, which is compacted by the pressing means, and A construction machine for building foundation, wherein a suspending means for suspending and carrying in a precast concrete foundation block from the outside is installed on the bottom surface in the groove.