JP2009041183A - Construction method for structure using precast concrete block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a construction method capable of reducing a construction cost by enabling precast concrete blocks to be surely joined together without the need for much labor. <P>SOLUTION: Firstly, the precast concrete blocks 10 are stacked in predetermined n-tiers; subsequently, part of a plurality of through-holes 11 are filled with a filler; a through reinforcement 13 is inserted; a cutting edge block 12 and the precast concrete block 10 are sunk; and after that, each time the precast concrete blocks 10 are stacked tier by tier, the filler is infilled into some of the remaining through-holes 11 of the precast concrete blocks 10 up to downward n-tiers including the uppermost tier, so that the through reinforcement 13 can be inserted. The above steps are repeated for the connection of the plurality of precast concrete blocks 10 to one another. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for constructing a structural frame by sequentially stacking precast concrete blocks.

  When constructing pneumatic caisson, reduction of construction cost is required. In order to respond to this, it is conceivable that the caisson is not constructed with cast-in-place concrete but a precast concrete block is formed in a work yard or the like, thereby constructing the caisson to shorten the construction period and reduce the cost. In this case, as a conventional method for joining the precast concrete blocks, there are a joining method using a mechanical joint of reinforcing bars and a method of crimping joining using a PC steel rod.

However, the pressure bonding method using a PC steel rod takes time and labor to fill the filler after inserting the PC steel rod, while the mechanical joint requires time and labor to attach and fix the coupler to the reinforcing bar. It could not be reduced.
In addition, although it is not related to the caisson method, as a conventional technique for joining the precast concrete blocks to each other, there is one in Patent Document 1.
JP 2000-352108 A

  The object of the present invention is to construct a structural frame by stacking a plurality of precast concrete blocks, so that the precast concrete blocks can be reliably joined to each other without relatively trouble, and the construction cost can be reduced. Is to provide a simple construction method.

  In the present invention, the above problems are solved by means (1) to (4) described below.

(1) A method of constructing a structural frame by sequentially stacking precast concrete blocks, wherein a plurality of through-holes are pre-formed in the stacking direction and stacked in a predetermined n number of stages, and a plurality of through-holes are stacked from the top. A method of constructing a structure, wherein precast concrete blocks are connected to each other by inserting through bars after filling the filler to the lowest level.

(2) A construction method for constructing a structural frame by sequentially stacking precast concrete blocks on a blade block constructed in advance, and a precast concrete block in which a plurality of through holes are previously formed in the stacking direction Stacking the number of stages, after filling the filler from the uppermost stage to the lowermost stage in a part of the plurality of through-holes and inserting the through bars, then sinking the blade block and the n-stage number of precast concrete blocks, One layer of precast concrete blocks is stacked, and a portion of the remaining through-holes is filled with n fillers from the top to the bottom, then through bars are inserted, and the blade block and the n number of precast concrete blocks sink. After that, every time the precast concrete blocks are stacked one by one, By repeating the step of inserting the muscle through by filling a filler in the through holes of the n stages downwardly from Les cast concrete blocks, method for constructing a structure which is characterized by combining the precast concrete blocks to each other.

(3) A method of constructing a structural frame by sequentially stacking precast concrete blocks, and each time a precast concrete block in which a plurality of through holes are formed in advance in the stacking direction is loaded step by step, a delayed curable filler is added. After filling the through-holes and n-stages of precast concrete blocks are stacked, the precast concrete blocks are connected to each other by inserting through bars from the top to the bottom of the through-holes filled with the filler. A construction method of a characteristic structure.

(4) A construction method for constructing a structural frame by sequentially stacking precast concrete blocks on a blade block constructed in advance, and the precast concrete block having a plurality of through holes formed in the stacking direction in advance. Each time it is stacked on top of each other, a delay curable filler is filled into the through holes, and when n stages of precast concrete blocks are stacked, a part of the through holes filled with the filler is partially inserted from the top. Inserting a streak to the lowest stage, sinking the blade block and the n-stage number of precast concrete blocks, and thereafter repeating the process of filling the filling material into the through holes each time the precast concrete blocks are stacked one by one , Through the uppermost precast concrete block, n bars are not inserted through the bottom. Once generated through hole of, by inserting the here through muscle, method for constructing a structure which is characterized by combining the precast concrete blocks to each other.

  In the above means (2), the “predetermined number of n stages” is 2 stages or more and the number of stages that can be filled without generating a gap when the filler is injected into the through hole of the precast concrete block from above. It is determined arbitrarily. For example, when the length of one precast concrete block in the stacking direction is about 200 cm, the predetermined number of n stages can be up to about four. Further, although not particularly limited, n stages are preferably about 3 stages.

  In the means of (4) above, “the number of n stages” means that two or more stages can be inserted through the through-holes of the n-stage precast concrete block filled with the delay curable filler. The number of steps is arbitrarily determined. For example, when the length of one precast concrete block in the stacking direction is about 200 cm, the number of n stages can be up to about four. Although not particularly limited, n stages are preferably about 3 stages.

  As the delayed-curing filler, a grout material or a cement composition that has a slower curing speed than ordinary mortar or concrete composition and usually requires about 3 days to 3 months for setting after placing is used. be able to. The period from placement of the delayed-curing filler to curing is arbitrarily determined according to the construction conditions.

  The cement composition may be, for example, a delayed-setting mortar composition, a delayed-setting concrete composition, or a delayed-setting cement paste composition depending on the aggregate to be blended.

  The delayed curable cement composition as the delayed curable filler is not particularly limited as long as it is a cement composition exhibiting the above action, but the setting time can be adjusted, and high compressive strength is obtained when cured. For example, a composition containing a cement such as low-heat Portland cement, ordinary Portland cement, or blast furnace cement, a setting retarder, a cement dispersant, and a separation reducing agent is preferable.

Examples of the setting retarder include lignin sulfonates, oxycarboxylates, gluconates, polyol organic derivatives, or mixtures of two or more of these, and the use of polyol organic derivatives is particularly preferable.
Examples of the cement dispersant include polycarboxylic acid polymer compounds, naphthalene sulfonic acid polymer compounds, alkylallyl sulfonic acid polymer compounds, melamine sulfonic acid polymer compounds, and mixtures of two or more of these. In particular, the use of a polycarboxylic acid polymer compound is preferable in terms of improving fluidity and the like with a low blending amount.
The separation reducing agent is preferably one that can maintain the separation reduction effect even in an environment heated by the heat of hardening of the cement, for example, at a high temperature of 90 ° C., for example, cellulose, cellulose ether, acrylic, glycol Or a mixture of two or more of these, and the use of a cellulose ether-based separation reducing agent is particularly preferred.

In addition to the above components, the delayed curable cement composition may further contain, for example, an inorganic admixture, an organic shrinkage reducing agent, an aggregate, or a mixture of two or more thereof, as necessary. Among these, by changing the kind and blending ratio of the inorganic admixture and the aggregate by a conventional method, the delayed curable cement composition is changed to, for example, the delayed curable mortar composition, the delayed curable concrete composition or the delayed cured composition. It can be set as an adhesive cement paste composition.
In general, the inorganic admixture preferably has an average particle size of 200 μm or less, particularly 100 μm or less. Examples of the inorganic admixture include stone powder such as limestone fine powder, silica fume, blast furnace slag fine powder, fly ash, or a mixture of two or more thereof.
Examples of the organic shrinkage reducing agent include alkylene oxide adducts of lower alcohols, polyethers, alcohols, low molecular weight alkylene oxide copolymers or glycol ether / amino alcohol derivatives, or mixtures of two or more of these. Can be mentioned.
Examples of the aggregate include fine aggregates having an average particle size of 150 μm or more and 40 mm or less, coarse aggregates having a larger average particle diameter, or a mixture thereof.
The delayed curable cement composition can contain, for example, water, a swelling agent, a rust preventive agent, an antifoaming agent, and the like in addition to the above-described components.

In the delayed curable cement composition, the blending ratio of each component can be appropriately selected and determined depending on the desired delay period, the strength to be obtained, and the like.
For example, the mass ratio of water to the total amount of cement and inorganic admixture is usually 20 to 50%, preferably 30 to 40%.
The mass ratio of the cement to the inorganic admixture when blending the inorganic admixture is from 2: 8 to 8 because the curing delay time can be sufficiently increased, bleeding can be prevented, and the amount of self-shrinkage can be reduced. : 2 is preferred.

The blending ratio of the cement dispersant is usually 0.05 to 3.5 parts by mass with respect to a total of 100 parts by mass of the cement and the inorganic admixture. By using this formulation, workability required for construction can be sufficiently secured.
The mixing ratio of the setting retarder is usually 0.15 to 1.0 part by mass with respect to 100 parts by mass in total of the cement and the inorganic admixture. By using this formulation, delayed curing over a long period of several days or more can be obtained.
The mixing ratio of the separation reducing agent is usually 0.05 to 1.0 part by mass with respect to 100 parts by mass in total of the cement and the inorganic admixture. By adopting this blending, for example, bleeding can be sufficiently suppressed even in a temperature condition during curing of the concrete at a high temperature of about 90 ° C. and in a long curing period of several days or more.

The blending ratio in the case of blending the organic shrinkage reducing material is usually 0.1 to 3.0 parts by mass with respect to 100 parts by mass in total of the cement and the inorganic admixture. By using this formulation, the self-shrinkage of the delayed curable cement composition can be sufficiently reduced.
When the aggregate is blended and the delayed-setting cement composition is used as the delayed-setting concrete or mortar composition, the blending ratio is usually 200 to 100 parts by mass with respect to a total of 100 parts by mass of the cement and the inorganic admixture. 800 parts by mass.
The mixing ratio of the water is usually 20 to 60 parts by mass with respect to 100 parts by mass in total of the cement and the inorganic admixture. By using this composition, curing delay time can be secured, bleeding can be prevented, and the amount of self-shrinkage can be reduced.

The construction method of (1) is characterized in that after a predetermined number of n stages of precast concrete blocks are stacked, a filling material is inserted into all the through holes, and through bars are inserted, and these series of steps are performed only once. Alternatively, by repeatedly performing a plurality of times, the joints between the precast concrete blocks are connected by any through bar.
Therefore, it is possible to securely connect the precast concrete blocks to each other with the thread without providing joints such as conventional mechanical joints at the upper and lower ends of the thread. Therefore, it is possible to save the labor of the conventional construction method, and the construction cost can be reduced.

In the construction method (2), first, a predetermined number of n stages of precast concrete blocks are stacked, and then, through holes are filled in a part of the plurality of through holes and through bars are inserted. Each time the stacks are stacked one by one, the process of filling a part of the remaining through-holes of the precast concrete block up to n stages including the uppermost part and inserting the thread is repeated. Even when the same length of the reinforcing bar is used, the upper and lower ends of all the reinforcing bars are not aligned with the same precast concrete block joint surface. can do.
Therefore, it is possible to securely connect the precast concrete blocks to each other with the thread without providing joints such as conventional mechanical joints at the upper and lower ends of the thread. Therefore, it is possible to save the labor of the conventional construction method, and the construction cost can be reduced.

In the method (3), each time a precast concrete block is loaded one by one, a delay curable filler is filled into the through holes, and when a predetermined n number of layers are stacked, all through holes are stacked from the top to the bottom. It is characterized by inserting a thread, and the precast concrete blocks can be connected to each other by carrying out the series of steps only once or repeatedly.
Therefore, it is possible to securely join the precast concrete blocks to each other with the thread without installing joints such as conventional mechanical joints at the upper and lower ends of the thread. The construction cost can be reduced by eliminating the labor of the conventional method.

In the method (4), each time the precast concrete blocks are stacked one by one, a plurality of through-holes are filled with a delay curable filler, and when a predetermined n-stages are stacked, a part of the plurality of through-holes is filled. Insert through thread, then fill each through-hole with delayed-curing filler each time the precast concrete blocks are stacked one by one, and the remaining through the precast concrete block up to n stages including the top Repeating the process of inserting the streak into a part of the hole, thereby filling the through hole of the precast concrete block without any gaps, and the through streak is reliably fixed in the through hole by the filler, Even if the same length of thread is used, the upper and lower ends of all thread are aligned with the joint surface of the specified precast concrete block. Without the junction of precast concrete blocks are connected with each other by either threading muscle.
Therefore, it is possible to securely join the precast concrete blocks to each other with the thread without installing joints such as conventional mechanical joints at the upper and lower ends of the thread. The construction cost can be reduced by eliminating the labor of the conventional method.

Hereinafter, although the embodiment of the present invention will be described with reference to a method of constructing the foundation structure by the caisson method, the present invention is not limited to this.
FIG.1 and FIG.2 is a perspective view which shows an example of the precast concrete blocks 10 and 20 used by this invention, and showed the state at the time of stacking two or more here.
In the caisson method, the precast concrete blocks 10 and 20 are formed in a short cylindrical shape as shown in FIG. 1 or a rectangular parallelepiped as shown in FIG. 2 in a factory or a work yard to constitute a box (frame) called caisson. It is manufactured in a shape and has a hollow portion in the central vertical direction. A plurality of sheath tubes and the like are embedded in the precast concrete blocks 10 and 20 and the through holes 11 and 21 are formed in advance in the stacking direction, and through bars such as reinforcing bars are inserted and stacked in the through holes 11 and 21. The precast concrete blocks 10 and 20 are joined together.

Next, the caisson method to which the present invention is applied will be described with reference to FIGS.
In FIGS. 3B to 3I, the left half of the precast concrete block 10 is shown in a side view and the right half in a cross-sectional view. In the present embodiment, three stages are illustrated as the predetermined n stages described above.

  First, the blade block 12 as shown in FIG. 3A is installed at a place where the foundation structure is constructed. The blade block 12 is used for excavating the ground downward and sinking a caisson while keeping the working chamber provided at the bottom thereof at a high pressure to prevent the intrusion of mud.

  Next, the precast concrete block 10 is lifted by a crane (not shown) or the like and is laid on the blade block 12 as shown in FIG. When the first-stage precast concrete block 10 is fixed on the blade block 12 by fixing means such as bolts and nuts, an adhesive made of epoxy resin or the like is applied to the upper end surface of the first-stage precast concrete block 10. Then, the second-stage precast concrete block 10 is installed as shown in FIG. 3C, and the third-stage precast concrete block 10 is installed similarly as shown in FIG. 3D. . At this time, a part of the through holes 11a of the through holes 11 of the uppermost precast concrete block 10 communicate to the lowermost stage, and the remaining part of the through holes 11b of the uppermost stage are only the second through holes 11. In addition, the uppermost remaining through-hole 11 c does not communicate with the second and lowermost through-holes 11. This is done by selectively providing a lid (not shown) in the through-hole 11 of the first-stage or second-stage pre-cast concrete block 10 so that the through-hole 11 of the pre-cast concrete block 10 that has been stacked three stages first is placed at the top. It is possible to appropriately adjust the distance from the upper stage to the communication.

  When the precast concrete blocks 10 are stacked in three stages, as shown in FIG. 3E, a filler (not shown) is injected into the through holes 11 communicating from the uppermost stage to the lowermost stage, and these through holes 11 through which a reinforcing bar 13 is inserted. Each reinforcing bar has the same length as that of the three-stage precast concrete block 10 in the stacking direction. At this time, a filler is inserted into the through hole 11b communicating only with the uppermost and second precast concrete blocks 10 and the uppermost through hole 11c not communicating with the second and lowermost through holes 11. Do not fill and do not insert the thread.

  When the filler filled in the through holes 11 from the uppermost stage to the lowermost stage is hardened, excavate the ground downward while keeping the working chamber provided at the bottom of the blade block 12 at a high pressure to prevent intrusion of mud, As shown in FIG. 3F, the caisson is sunk to a predetermined depth.

Next, when an adhesive is applied to the upper end surface of the uppermost precast concrete block 10 and the first precast concrete block 10 is further stacked as shown in FIG. 3 (g), the filler and thread are still provided. The through-hole 11 in the void state has three different lengths, that is, the through-hole 11c only in the uppermost precast concrete block 10, and the through hole communicating with the lower two-stage precast concrete block 10 including the uppermost stage. A hole 11b and a through hole 11a communicating with the three-stage precast concrete block 10 are formed below including the uppermost stage.
The filler material is injected only into the through hole 11a communicating with the three-stage precast concrete block 10 downward including the uppermost stage, and the communicating through hole 11a is formed as a thread 13 as shown in FIG. 3 (h). Insert a reinforcing bar. When the filler is cured, the caisson is sunk to a predetermined depth as shown in FIG.

Thereafter, similarly, an adhesive is applied to the upper end surface of the uppermost precast concrete block 10, and one stage of the precast concrete block 10 is loaded thereon, and the three stages of the precast concrete block 10 are communicated downward including the uppermost stage. A base structure can be constructed by injecting a filler from above only into the through-hole 11a to be inserted, inserting a thread through it, and repeating the steps of sinking the caisson.
Even if the foundation structure constructed in this way uses the same length of thread 13, the upper and lower ends of all the threads 13 are aligned at the joint surface of the same precast concrete block 10. None of the through bars 13 connect the joints between the precast concrete blocks. Thus, the precast concrete blocks 10 can be reliably joined to each other with the thread 13 without providing a conventional joint such as a mechanical joint at the upper and lower ends of the thread 13.

Next, a method different from the caisson method described above will be described with reference to FIGS. 3 (a) to 3 (i).
First, the blade block 12 as shown in FIG. 3A is installed at a place where the foundation structure is constructed, and the first stage as shown in FIG. The precast concrete block 10 is constructed and fixed, and a delay curable filler (not shown) is injected into the through hole 11 of the first precast concrete block 10 from above.

Next, an adhesive made of epoxy resin or the like is applied to the upper end surface of the first-stage precast concrete block 10, and the second-stage precast concrete block 10 is installed thereon as shown in FIG. 3 (c). Then, a delayed curable filler is injected into the second-stage through-hole 11 from above, and an adhesive is applied to the upper end surface of the second-stage precast concrete block 10 in the same manner as shown in FIG. As shown, the third-stage precast concrete block 10 is erected, and a delay curable filler is injected into the third-stage through hole 11 from above.
At this time, a part of the through holes 11a of the through holes 11 of the uppermost (third stage) precast concrete block 10 communicate to the lowermost stage, and the remaining part of the through holes 11b of the uppermost stage is the second stage. When the precast concrete blocks 10 are stacked in three stages, the uppermost remaining through-holes 11c are not in communication with the second and lowermost through-holes 11; As shown in Fig. 5, the reinforcing bars as the through bars 13 are inserted only into the through holes 11a communicating from the uppermost stage to the lowermost stage. Each reinforcing bar has the same length as that of the three-stage precast concrete block 10 in the stacking direction. At this time, a through line is formed between the through hole 11b communicating only with the uppermost and second precast concrete blocks 10 and the uppermost through hole 11c not communicating with the second and lowermost through holes 11. Do not insert.
When the delayed curable filler in the through hole 11a in which the thread 13 is inserted is hardened, the ground at the bottom of the blade block 12 is excavated downward, and the caisson is brought to a predetermined depth as shown in FIG. Sink.

  Next, an adhesive is applied to the upper end surface of the uppermost precast concrete block 10, and the first precast concrete block 10 is stacked as shown in FIG. To do. Accordingly, only the through hole 11c of the uppermost precast concrete block 10 includes the through hole 11b communicating with the lower two-stage precast concrete block 10 including the uppermost stage, and the lower third precast concrete including the uppermost stage. The through-hole 11a communicating with the block 10 is filled with a filler, but the thread is not yet inserted. As shown in FIG. 3 (h), reinforcing bars as through bars 13 are inserted into the through-holes 11a communicating with the three-stage precast concrete block 10, and when the filler in the through-holes 11a is cured, FIG. As shown, the caisson is submerged to a predetermined depth.

  Thereafter, similarly, an adhesive is applied to the upper end surface of the uppermost precast concrete block 10, the precast concrete blocks 10 are loaded one by one here, and a filler is injected into the through-hole 11 from above, and then the uppermost stage Inserting a streak through the through hole 11a communicating with the three-stage precast concrete block 10 in the downward direction and hardening the filler in the through hole 11a, the caisson is laid down a predetermined number of times to repeat the foundation structure. Can be built.

  In the foundation structure constructed in this way, the filling material is reliably filled in the through hole of the precast concrete block without any gap, and the through line can be reliably fixed in the through hole by the filling material. Further, the upper and lower end portions of the through bars are not aligned at the joint surface of the same precast concrete block, and the joint portions of the precast concrete blocks are connected by any of the through bars. Therefore, it is possible to join the precast concrete blocks with threading bars without providing joints such as conventional mechanical joints at the upper and lower ends of the threading bars, which is necessary for the construction of the joints. The construction cost can be reduced without the trouble of the conventional construction method.

Next, with reference to FIG. 4 (a)-(d), the process of filling the filler 14 in the through-hole 11 of the precast concrete block 10 is demonstrated.
The filler 14 is filled with a necessary amount so as not to overflow from the through hole 11 as shown in FIG. When the transparent pipe 15 is attached to the upper end of the through hole 11 as shown in FIG. 4B and then the reinforcing bar as the through bar 13 is inserted into the through hole 11, the filler 14 is shown in FIG. 4C. As such, it overflows from the through hole 11 and rises into the transparent pipe 15. When the breathing water 16 accumulates above the transparent pipe 15 after a lapse of time, the upper surface position of the filler 14 is confirmed, and when it is lower than the upper end surface of the precast concrete block 10, the filler 14 is replenished. As shown in (d), when it is filled to a high position, the transparent pipe 15 is cut at the position of the upper end surface of the precast concrete block 10. By filling the filler 14 in this way, it is possible to prevent a void from being generated in the filler 14 in the through hole 11.

It is a perspective view which shows an example of the precast concrete block used by this invention. It is a perspective view which shows an example of the precast concrete block of a shape different from FIG. 1 used by this invention. (A)-(i) is a simple figure for demonstrating each process of the caisson method to which this invention is applied, In (b)-(i), the left side half of a precast concrete block is a side view, The right side half is Shown in cross section. (A)-(d) is a figure for demonstrating the process at the time of filling a filler in the through-hole of a precast concrete block.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Precast concrete block 11 Through-hole 11a, 11b, 11c Through-hole 12 Cutting edge block 13 Through thread 14 Filler 15 Transparent pipe 16 Breathing water 20 Precast concrete block 21 Through-hole

Claims (4)

It is a construction method to build a structural frame by sequentially stacking precast concrete blocks,
Precast concrete blocks in which a plurality of through-holes are pre-formed in the stacking direction are stacked in a predetermined n number of stages, and fillers are filled into the plurality of through-holes from the top to the bottom, and then through bars are inserted. A method for constructing a structure, wherein blocks are connected to each other. It is a method of building a structural frame by sequentially stacking precast concrete blocks on the blade block constructed in advance,
After stacking a predetermined number of n stages of precast concrete blocks in which a plurality of through holes are formed in advance in the stacking direction, filling a filler from the uppermost stage to the lowermost stage in a part of the plurality of through holes, The blade block and the n-stage number of precast concrete blocks are sunk, and then the precast concrete blocks are stacked one stage, and the remaining through-holes are partially filled with n stages of fillers from the top to the bottom. Insert a streak to sink the edge block and the n number of precast concrete blocks. After that, each time the precast concrete blocks are stacked one by one, the nth through-hole is filled downward from the top precast concrete block. By repeating the process of filling the material and inserting the thread, Method for constructing a structure which is characterized by coupling the strike concrete blocks to each other. It is a construction method to build a structural frame by sequentially stacking precast concrete blocks,
Each time a precast concrete block in which a plurality of through holes are pre-formed in the stacking direction is loaded one by one, a delay curable filler is filled into the through holes, and when the n number of precast concrete blocks are stacked, the filler A method for constructing a structure, wherein precast concrete blocks are connected to each other by inserting through bars from the uppermost stage to the lowermost stage in the filled through holes. It is a method of building a structural frame by sequentially stacking precast concrete blocks on the blade block constructed in advance,
Each time a precast concrete block in which a plurality of through holes are pre-formed in the stacking direction is loaded on the blade block one by one, a delay curable filler is filled into the through holes, and n stages of precast concrete blocks are stacked. Then, through the through hole filled with the filler, a thread is inserted from the uppermost stage to the lowermost stage, and the blade block and the n-stage number of precast concrete blocks are submerged. Thereafter, the precast concrete block Repeat the process of filling the through hole with the filler each time one layer is stacked, and when a through hole with n stages through the top of the uppermost precast concrete block is not inserted, insert the through line here. By connecting precast concrete blocks to each other How to build a creation.

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