KR20220001218A - Method of continual concrete pavement using high viscosity coating type concrete setting retarder composition - Google Patents

Abstract

The present invention relates to a placing a concrete in contact with a hardened concrete method using a high-viscosity coating type concrete setting retarder composition, comprising: a step (S10) of pouring old concrete or old mortar; a step (S20) of applying a high-viscosity coating-type concrete setting retardant composition including a thickener, citric acid, and a nonionic surfactant to the surface of placing the concrete in contact with the hardened concrete in the old concrete or the old mortar; a step (S30) of removing a latency formed on the surface of placing the concrete in contact with the hardened concrete; and a step (S40) of pouring a new concrete or a new mortar on the surface of placing the concrete in contact with the hardened concrete. An objective of the present invention is to provide the method for uniformly exhibiting an effect of delay of condensation on an entire cross section even on the joint surface forming the vertical or inclined surface.

Description

The continuous method using a high viscosity coating type concrete setting retarder composition {Method of continual concrete pavement using high viscosity coating type concrete setting retarder composition}

The present invention relates to an ear-to-piece method for uniformly exhibiting the effect of setting delay on the entire cross-section even on an ear-to-ear surface forming a vertical or inclined surface.

In general, for reinforced concrete structures, when the pouring space is wide, it is impossible to complete all the pouring work in one day, and the amount of ready-mixed concrete supplied during the day is limited.

The splicing part is made intentionally according to the construction design or is caused by the interval of the pouring time within one pouring section due to the situation of the work. can be

On the other hand, bleeding refers to a phenomenon in which aggregate and cement powder settle due to the difference in specific gravity of each material after concrete is poured, and small air bubbles and fine substances rise along with moisture. The fine material that bleeds and accumulates on the surface is called laitance, and since laitance causes a decrease in adhesion between concrete, it is necessary to remove the laitance from the joint surface.

Accordingly, various treatment methods for the joint surfaces have been suggested. For example, a method of removing the surface layer with pressure water before setting and hardening of concrete has been proposed, but this has difficulties in controlling the timing of removing the surface layer, and excessive treatment may cause the aggregate to loosen. Possibility exists, processing time is limited, and there are disadvantages in that efficiency is poor.

In addition, a method of chipping with a chipper after coagulation and hardening of concrete is known, but this is because the aggregate is loosened and the strength of the concrete structure is lowered due to adhesion of the joint part, lowering of tensile strength, and separation of the adhesive between reinforcing bars and concrete. , there is a problem that the amount to be removed is large and unnecessary work is many, and the efficiency is also lowered. As another method, a method of surfacing with a wire brush or pneumatic hammer chisel has been reported, and the efficiency of this method is better than that of a manpower chipper, but it is inefficient overall, and has a problem of being unenvironmental due to dust generation.

In addition, a method of applying adhesive and pouring new concrete after hardening of concrete has been reported, but this causes an interface due to the latency of old concrete, deterioration of structure strength and durability due to inhibition of integration, and interfacial leakage of the joint surface. There is a disadvantage that double work is required in parallel with chipping work for performance expression.

As an example of the prior art, Korean Patent Registration No. 10-1407426 discloses a method for delaying the setting of the surface of mortar or concrete, comprising the following steps: A. For forming fresh mortar or concrete surface or fresh mortar or concrete applying, to the inner surface of the mold, a flowable or sprayable hot melt coating composition, wherein the hot melt coating composition is a molten vegetable oil or derivative thereof, a molten animal oil or derivative thereof, or the oil or a derivative thereof at least one set retardation activator suspended in a molten mixture of may be removed from the mortar or concrete, wherein the at least one set retardation activator comprises a carboxylic acid or a salt thereof, a sugar, or a mixture thereof; B. Cooling the hot melt coating composition applied to the mortar or concrete surface to ambient temperature, whereby the mortar or concrete in contact with the hot melt coating composition is cooled to ambient temperature to form a membrane in which the hot melt coating composition is solidified, , wherein the solidified membrane minimizes evaporation of moisture from the mortar or concrete; and C. then removing the solidified membrane from the mortar or concrete using pressurized water to expose the mortar or concrete surface that has been roughened by the at least one set retardation activator.

In the case of the above technology, the removal of latency is facilitated through the delay of setting of the ear-to-earth surface, but in particular, when the ear-to-ear surface forms a vertical or inclined surface, the effect of delay of setting is reduced due to the flowing down of the applied coating composition. There is a problem of non-uniformity.

Korean Patent Registration No. 10-1407426

The present invention was invented to solve the problems of the prior art as described above, and the present invention not only improves the effect of the setting delay, but also uniformly reduces the setting delay over the entire cross-section even on a vertical or inclined surface. It is intended to provide a method that allows the effect to be expressed.

The continuous method (hereinafter referred to as "the method of the present invention") using the high-viscosity coating type concrete setting retarder composition according to the present invention for achieving the above object is a step of pouring old concrete or old mortar (S10) ; Step (S20) of applying a high-viscosity coating-type concrete setting retardant composition comprising a thickener, citric acid, and a nonionic surfactant to the next surface of the old concrete or the old mortar (S20); removing the latency formed on the continuation surface (S30); It characterized in that it comprises; pouring new concrete or new mortar to the surface (S40).

As an example, in the step S10, the step of installing a formwork (S11); Applying a high-viscosity coating-type concrete setting retardant composition comprising a thickener, citric acid, and a nonionic surfactant to the inner periphery of the formwork in contact with the continuous surface as a formwork (S12); It characterized in that it comprises; the step (S13) of pouring the old concrete or the old mortar in the formwork.

As an example, in the step S30, it is characterized in that the form in contact with the tooth surface is dismantled, and the laitance and cement paste formed on the ear tooth surface are removed.

As an example, in step S30, it is characterized in that the laitance and cement paste are removed by high-pressure watering.

As an example, the high-viscosity coating type concrete setting retarder composition further comprises coconut oil fatty acid.

As an example, the high-viscosity coating type concrete setting retarder composition further comprises magnesium aluminum silicate.

As an example, the high-viscosity coating type concrete setting retarder composition further comprises metasilicate.

As described above, the method of the present invention improves the setting delay of the connecting surface when connecting using concrete or mortar, and in particular, when the connecting surface forms a vertical or inclined surface, the flow is controlled on the formwork surface, etc. As a result, the setting retardant is uniformly applied, which has the advantage of exhibiting a uniform effect of delaying setting of the interdigital surface. There is an advantage in that it is possible to remove the latency, so that the ease of construction can be promoted.

1 and 2 are block diagrams showing the method of the present invention.
Figure 3 is a photograph comparing the state in which the secondary coagulant is sprayed, respectively, when the composition of the present invention is sprayed on the formwork surface and when not sprayed.
Figure 4 is a photograph showing the state of chipping the concrete surface after using the composition of the present invention.
5 is a graph comparing the efficiency of chipping using an electric hammer breaker and chipping using the composition of the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in detail.

The method of the present invention comprises the steps of pouring old concrete or old mortar as shown in FIG. 1 (S10); Step (S20) of applying a high-viscosity coating-type concrete setting retardant composition comprising a thickener, citric acid, and a nonionic surfactant to the next surface of the old concrete or the old mortar (S20); removing the latency formed on the continuation surface (S30); It characterized in that it comprises; pouring new concrete or new mortar to the surface (S40).

In the step S10, it is characterized in that it comprises the step of first installing the formwork and pouring the old concrete or the old mortar to the formwork.

Here, when the method of the present invention is connected in the upward direction, after installing the formwork in step S10 and pouring the old concrete or old mortar into the formwork, the next step (S20) is connecting the old concrete or old mortar By directly spraying the high-viscosity coating-type concrete setting retarder composition on the surface, the high-viscosity coating-type concrete setting retarder composition is applied to the next surface.

In this case, in step S20, after pouring the old concrete or old mortar, the surface of the joint is smoothed and the high-viscosity coating type concrete setting retarder composition is applied to the surface of the joint before bleeding occurs.

In addition, in the case of the construction method of the present invention, in the case of the transverse splicing, as shown in FIG. 2 , in the step S10, the step of installing a formwork (S11); Applying a high-viscosity coating-type concrete setting retardant composition comprising a thickener, citric acid, and a nonionic surfactant to the inner periphery of the formwork in contact with the continuous surface as a formwork (S12); It characterized in that it comprises; the step (S13) of pouring the old concrete or the old mortar in the formwork.

In this way, after applying the high-viscosity coating type concrete setting retarder composition to the inner periphery of the formwork, the old concrete or old mortar is poured as the next step. to allow the retarder composition to be applied.

In this case, in the step S30, it is characterized in that the form in contact with the tooth surface is dismantled and the laitance and cement paste formed on the tooth surface are removed.

On the other hand, the high-viscosity coating type concrete setting retarder composition in step S20 (including step S12) is characterized in that it contains a thickener, citric acid, and a nonionic surfactant.

Preferably, the thickener is a vegetable thickener or an associative thickener.

The vegetable thickener serves to thicken the formwork so that the setting retardant does not flow down, so that the flow is controlled even when a gradient is formed as mentioned above.

Here, the vegetable thickener is not limited in its type, and for example, at least from the group consisting of methyl cellulose, ethyl cellulose, CMC (carboxy methycellulose), carboxy methyl cellulose sodium, carboxy methyl cellulose calcium, carboxy methyl cellulose calcium, and carboxy methyl cellulose sodium. One selection may be applied.

The associative thickener has a severe viscosity change due to temperature changes in the four seasons, making it difficult to apply in some cases. This is to minimize the change in viscosity according to temperature. That is, to facilitate the maintenance of a constant viscosity.

The type of the associative thickener is also not limited, and for example, a mixture of an associative urethane-based thickener and an associative acrylic thickener may be used. Associative type urethane thickeners have low yield stress and high plastic viscosity, and acrylic thickeners have high yield stress and high plastic viscosity, so that it is easy to maintain a certain viscosity by using an appropriate mixture.

The citric acid serves to inhibit the hydration of cement. In other words, it is to delay the setting of the joint surface so that the concrete can be chipped easily even after a long period of time.

The non-ionic surfactant is to allow the other compositions to be uniformly dispersed to express uniform physical properties. Here, the type of the nonionic surfactant is not limited, either, and for example, a primary or secondary alcohol-based nonionic having a linear or branched alkyl or alkenyl group having 8 to 22 carbon atoms and containing 1 to 25 moles of ethylene oxide. Surfactants and alkyl polyglycoside-based nonionic surfactants having a linear or branched alkyl or alkenyl group having 8 to 22 carbon atoms may be used.

In addition, as a fatty acid amide-based nonionic surfactant, it has a linear or branched alkyl or alkenyl group having 8 to 22 carbon atoms, and the fatty acid amide is in the form of ammonia amide, monoethanol amide, diethanol amide or isopropanolamide. Nonionic surfactants may be used.

Preferably, the composition of the present invention contains 1 to 20 parts by weight of an associative thickener, 10 to 70 parts by weight of citric acid, 5 to 50 parts by weight of phosphoric acid, and 1 to 20 parts by weight of a nonionic surfactant based on 100 parts by weight of a vegetable thickener under normal atmospheric pressure. It is reasonable to mix in proportions.

In the preparation example of the composition of the present invention, 1/2 of water is first weighed in a tank, 1/2 of phosphoric acid and citric acid water are sequentially added, mixed for 5 to 10 minutes, then the entire amount of nonionic surfactant is added, mixed for 5 to 10 minutes, and finally It can be prepared after weighing a vegetable thickener and an associative thickener, putting it in a tank, and mixing it for 20 to 30 minutes.

On the other hand, in the case of the composition of the present invention, a thickener is added to control the flow on the formwork surface, and due to the addition of the thickener, unhardened concrete or mortar can be gelated early on the surface to be formed. Since the effect of may be insignificant, in the composition of the present invention, coconut oil fatty acid is further added to prevent premature gelation despite the addition of a thickener. That is, more coconut oil fatty acid is added so that the effect of delaying setting is expressed as it is despite the addition of a thickener.

Preferably, it is reasonable to mix 1 to 5 parts by weight of coconut oil fatty acid with respect to 100 parts by weight of the vegetable thickener.

On the other hand, when bleeding is in progress, water is generated on the surface of the joint, and the generated water strengthens the cohesive force between particles and agglomerates between the latency particles. It may act as an impeding factor and may act as a factor impairing structural integrity by generating latency on the side of the connection after construction.

Accordingly, the present invention provides an example in which magnesium aluminum silicate is further included in addition to the above compositions. The magnesium aluminum silicate absorbs and removes water generated in bleeding to prevent agglomeration between the latency particles. This is to promote bleeding on the joint surface and to cause bleeding of almost all the amount of latency that can be precipitated in concrete or mortar within the duration of the delay effect by the above compositions.

Preferably, it is appropriate to mix 1 to 5 parts by weight of magnesium aluminum silicate with respect to 100 parts by weight of the vegetable thickener.

In addition, an example in which metasilicate is further included in the composition of the present invention is provided in addition to the above compositions, so that the repulsive force between the tooth surface and the latency particles is enhanced by the addition of metasilicate.

That is, this is to further increase the latency removal efficiency by chipping by increasing the repulsive force between the ear surface and the latency particles.

The addition of magnesium-aluminum silicate controls the cohesion between the latency so that sufficient latency is deposited on the tooth surface, and the addition of metasilicate allows the deposited latency to be firmly attached to the tooth surface to control chipping. to make this easy.

Preferably, it is reasonable to mix 1 to 5 parts by weight of metasilicate based on 100 parts by weight of the vegetable thickener.

In addition, the composition of the present invention provides an example in which a phosphoric acid-based copolymer high dispersant is further included in addition to the above compositions. By using a phosphoric acid-based copolymer high dispersion agent, due to electrical repulsion and side chain structure, cement or fly ash is more dispersed to lower the viscosity of the connecting surface. In other words, the effect of delaying condensation is doubled.

Hereinafter, the effect of the high-viscosity coating type concrete setting retarder composition will be described through experiments with reference to FIGS. 3 to 5 .

As shown in FIG. 3 by the above compositions, the results of applying the setting retardant secondarily to the surface of the formwork with and without the composition of the present invention are shown. As shown in the photo, it can be seen that in the case of the non-coated formwork, the setting delay agent flows down, whereas when the existing setting retarder is applied after the composition of the present invention is pre-applied to the formwork, dripping does not occur. it can be seen that

That is, it can be predicted that the composition of the present invention and the secondary setting retarder are uniformly applied to the entire formwork, so that the effect of setting delay is uniformly expressed over the entire tooth surface in contact with the formwork.

In this way, when the composition of the present invention is applied to the toothed surface, as shown in FIG. 4 , it can be visually confirmed that the latitude of the toothed surface is removed only by sprinkling of high-pressure water.

In addition, as shown in FIG. 5, in the case of chipping using a conventional electric hammer breaker, the chipping efficiency was compared with the chipping efficiency after application of the composition of the present invention. it can be seen that

As described above, the method of the present invention is applied directly to the surface of the joint or to the form in contact with the surface of the joint when constructing concrete or mortar, so that even if a slope is formed on the surface of the joint, the flow is controlled. As the coating state is maintained on the entire surface, the effect of delaying condensation is evenly expressed. This is to facilitate ease of use. That is, in the step S30, it is characterized in that the latency is removed only by high-pressure watering.

Finally, there is a step (S40) of pouring new concrete or new mortar on the connecting surface, so that the structure is completed by repeating steps S10 to S40.

As described above, although the present invention has been described with reference to the limited embodiments and drawings, the present invention is not limited to the above embodiments, of course, from the above description by those of ordinary skill in the art to which the present invention pertains. Of course, various modifications and variations may be possible.

Claims (7)

pouring old concrete or old mortar (S10);
Step (S20) of applying a high-viscosity coating-type concrete setting retardant composition comprising a thickener, citric acid, and a nonionic surfactant to the next surface of the old concrete or the old mortar (S20);
removing the latency formed on the surface to be connected (S30);
pouring new concrete or new mortar on the continuous surface (S40);
A continuous method using a high-viscosity coating type concrete setting retarder composition comprising a.
The method of claim 1,
In step S10,
Installing the formwork (S11);
Applying a high-viscosity coating-type concrete setting retarder composition comprising a thickener, citric acid, and a nonionic surfactant to the inner surface of the formwork in contact with the continuous surface as a formwork (S12);
A continuous method using a high-viscosity coating type concrete setting retarder composition comprising a; (S13) of pouring old concrete or old mortar into the formwork.
3. The method of claim 2,
In the step S30, the repeating method using the high-viscosity coating type concrete setting retarder composition, characterized in that by dismantling the form in contact with the repeating surface and removing the latency and cement paste formed on the repeating surface.
The method of claim 1,
In step S30, the high-viscosity coating type concrete setting retardant composition, characterized in that the laitance and cement paste are removed by high-pressure water spraying.
The method of claim 1,
The high-viscosity coating-type concrete setting retarder composition further comprises coconut oil fatty acid.
The method of claim 1,
The high-viscosity coating-type concrete setting retarder composition further comprises magnesium aluminum silicate.
The method of claim 1,
The high-viscosity coating-type concrete setting retarder composition further comprises a metasilicate.

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