JP2006096627A - Injection material for open-graded mixture, and method of constructing semi-flexible structure using the injection material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection material for an open-graded mixture which expresses strength in a short time, enables securing of workability and good injection into an existing open-graded mixed structure by keeping good initial fluidity, and can improve fillability, and also to provide a simple and easy construction method for a semi-flexible structure excellent in durability. <P>SOLUTION: The injection material is obtained by blending a high performance water reducer of 0.2-1.6 pt.wt., a lignin-based retardant of 0.2-1.2 pt.wt. and an oxycarboxylic acid-based retardant of 0.01-0.30 pt.wt. based on 100 pts.wt. of a mixture material having the blending ratio of 50-80 wt% extra-quick hardening cement and 20-50 wt% fly ash classified to ≤20 μm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an injection material for an open particle size mixture and a method for constructing a semi-flexible structure using the injection material, and more particularly, to an open particle size type asphalt mixture in road pavement work and an opening adjacent to a joint portion of the structure. An injection material for an open particle size mixture that is injected into a particle size mixture structure to provide effective waterproofing, and a vibration-free injection that can easily reduce noise when the injection material is injected into an open particle size mixture structure The present invention relates to a method for constructing a semi-flexible structure using the injection material.

In general, the semi-flexible pavement is constructed by injecting and infiltrating cement milk for infiltration into a base material of an open-graded asphalt mixture structure having a large porosity.
Such semi-flexible pavements are constructed on road pavements such as roadways and sidewalks, for example, but there are many road reworks that involve traffic restrictions, and it is required to open traffic as soon as possible.
In view of this point, a large number of semi-flexible pavement injection materials and semi-flexible pavement construction methods have been proposed.

For example, in JP-A-6-183812, high flowability is maintained for a long time by using two types of retarders of different systems (lignin retarder and oxycarboxylic acid retarder) in combination with ultrafast cement. It has been proposed that a high-fluidity ultra-fast cement composition that has a low impact on strength development in a short time and that a semi-flexible pavement is constructed using the composition. No. 10-1345 discloses a one-powder polymer cement for semi-flexible pavement prepared by uniformly mixing cement, limestone fine powder, silica sand, re-emulsifiable powder resin and powder additive in a predetermined ratio. A composition is disclosed.
Japanese Patent Application Laid-Open No. 11-228205 proposes a semi-flexible pavement material containing cement, a rapid hardening material containing calcium aluminate and sulfate, and a non-re-emulsifying fine powder elastic polymer. .

  However, the above-mentioned conventional semi-flexible pavement injection material can be filled with injection material when the open-graded asphalt concrete mixture structure to be injected is the newly opened open-graded asphalt concrete mixture structure. However, in reality, for example, repair work on existing roads and the like is mostly repair work on open-graded mixture structures where clogging or crushing of voids occurs, and such clogging or crushing of gaps occurs. It is difficult to inject and fill a conventional injecting material into an open particle size mixture structure, which solidifies before permeating, resulting in a deterioration in quality and a sufficient working time.

  In addition, in the conventional semi-flexible pavement injection material, the compounded silica sand and re-emulsifying resin are injected into the open particle size mixture structure in which void clogging or crushing occurs. Since fly ash contained as a material separation preventing material is a by-product in a thermal power plant, quality variation is large and uniform performance cannot be obtained.

Furthermore, in the operation of injecting the conventional injection material for an open particle size mixture, it is usual to use a plate or a vibrating roller, and noise is generated, which is a big problem particularly in night construction.
JP-A-6-183812 Japanese Patent Laid-Open No. 10-1345 JP 11-228205 A

Accordingly, the object of the present invention is to show strength development in a short time, maintain good initial fluidity and ensure workability, and to be injected into an existing open particle size mixture structure, It is to provide an injection material for an open particle size mixture capable of improving the filling property.
In particular, the present invention provides an injection material for an open particle size mixture which can smoothly penetrate and fill an existing open particle size mixture structure and can shorten the entire construction period.
Still another object of the present invention is to provide a method for constructing a semi-flexible structure which is simple and excellent in durability using the above-mentioned injection material for open particle size mixture of the present invention.

  As a result of researches to solve the above-mentioned problems, the present inventors have found that a super-high-hardness cement is blended with classified fly ash, a high-performance water reducing agent, a lignin-based retarder, and an oxycarboxylic acid-based retarder. It has been found that the use of cementitious ultrafast cement composition as cement milk makes it possible to improve the injectability into an existing open particle size mixture and improve the filling property, and the present invention has been achieved.

The injection material for open particle size mixture according to the present invention comprises 50 to 80% by weight of super fast hard cement and 100 parts by weight of the cement / fly ash mixed material having a blending ratio of 20 to 50% by weight of fly ash classified to 20 μm or less. In contrast, 0.2 to 1.6 parts by weight of high-performance water reducing agent, 0.2 to 1.2 parts by weight of lignin-based retarder and 0.01 to 0.30 parts by weight of oxycarboxylic acid-based retarder It is characterized by becoming.
Preferably, in the injection material for open particle size mixture according to the present invention, 12% by weight or less of the blended amount of fly ash with respect to the super fast cement is substituted with calcium carbonate powder.

The method of constructing a semi-flexible structure using the injection material for open particle size mixture of the present invention is prepared by mixing 45 to 60 parts by weight of water with 100 parts by weight of the injection material for open particle size mixture of the present invention. And then injecting and supplying the cement milk to the open particle size mixture structure, and the supplied cement milk penetrates into the voids of the mother body of the open particle size mixture structure.
Preferably, in the construction method of the semi-flexible structure of the present invention, the method further comprises a step of spraying fine aggregates in an amount of 0.2 to 1.0 kg / m ² after injecting and supplying cement milk. To do.

The injection material for an open particle size mixture according to the present invention is a high-fluidity ultrafast cement composition comprising fly ash classified into ultrafast cement, a high-performance water reducing agent, a lignin retarder and an oxycarboxylic acid retarder. By making into cement milk, the injection into the existing open particle size mixture in which void clogging or void crushing occurs becomes good, and the filling property can be improved.
In this way, the initial fluidity is high and the filling and filling of the existing open particle size mixture is good, so that the entire construction period can be shortened and the traffic can be opened quickly at the existing road paving site. .

Further, in the method of constructing the semi-flexible structure of the present invention, immediately after the injection material of the present invention is injected into the open particle size mixture structure, the fluidity is high and uniformly penetrates into the voids. After the injection and filling of the material, the curing reaction proceeds rapidly after a certain time, and the construction period can be greatly shortened.
Furthermore, the construction method of the semi-flexible structure according to the present invention can make the existing open-graded mixture impervious, so that the paved road surface can be raised without cutting, and the construction period for barrier-free construction can be shortened and the cost can be reduced. In addition, the joint part can be waterproofed.
Moreover, since the filling property is good, an open particle size mixture that does not cause clogging or crushing of voids can be injected without vibration, and no noise problem occurs, which is environmentally desirable.

The present invention is illustrated by the following preferred examples, but is not limited thereto.
The injection material for open particle size mixture according to the present invention comprises 50 to 80% by weight of super fast hard cement and 100 parts by weight of the cement / fly ash mixed material having a blending ratio of 20 to 50% by weight of fly ash classified to 20 μm or less. On the other hand, 0.2 to 1.6 parts by weight of high-performance water reducing agent, 0.2 to 1.2 parts by weight of lignin retarder and 0.01 to 0.30 parts by weight of oxycarboxylic acid retarder It is made.
Or 12 weight% or less of the compounding quantity of the fly ash with respect to the said super-hard-hardening cement is substituted with a calcium carbonate powder.
By using such a composition, it is possible to improve the filling property by improving the filling property to the existing open particle size mixture in which gap clogging or crushing occurs, and for example, early in road pavement where traffic opening is required at an early stage Strength development can be made possible.

The super fast hard cement used for the injection material for open particle size mixture of the present invention is not particularly limited, and various fast hard cements available on the market such as Irwin cement and calcium aluminate cement can be used.
The ultrafast cement is contained in a mixture with fly ash in an amount of 50 to 80% by weight, preferably 60 to 70% by weight. By blending the super-hard cement at such a content, it is possible to open the road at an early stage after the completion of construction such as road paving work.
Particularly preferably, it is blended in an amount of 60 to 70% by weight.

Further, the fly ash used for the injection material for the open particle size mixture of the present invention has an effect of improving the fluidity of the obtained injection material and preventing the settlement of the semi-flexible structure after injection by material separation, In particular, fly ash classified to 20 μm or less is suitable for ensuring good penetrability into an existing open particle size mixture.
The blending amount of the fly ash is 20 to 50% by weight, preferably 30 to 40% by weight, in the mixed material with the ultrafast cement.
By setting it as such a blending ratio, the penetrability into the existing drainage mixture is improved.

In addition, a part of the fly ash can be replaced with calcium carbonate powder, and the calcium carbonate powder is 0.0 to 12% by weight in 20 to 50% by weight of fly ash to be blended with the ultrafast cement. Preferably, 2 to 10% by weight can be replaced with calcium carbonate powder.
When calcium carbonate is used, there is less variation in quality compared to fly ash, material separation of the resulting injection material is difficult to occur, semi-flexible structure settlement due to material separation after injection is prevented, and hydration is achieved. A reaction can also be expected.

  The injection material for an open particle size mixture according to the present invention comprises the above ultrafast cement and fly ash in an amount of 50 to 80 wt%, preferably 60 to 70 wt%, fly ash 20 to 50 wt%, preferably 30 to 70 wt%. A high-performance water reducing agent, a lignin retarder and an oxycarboxylic acid retarder are contained in the following blending amounts with respect to 100 parts by weight of the mixed material blended with 40% by weight.

As the high performance water reducing agent, various high performance water reducing agents available in the market such as polycarboxylic acid type, aminosulfonic acid type, naphthalene sulfonic acid type and melamine type can be used, and are not particularly limited.
The blending amount of the high-performance water reducing agent is 0.2 to 1.6 parts by weight, preferably 0.4 to 1.1 parts by weight of the high-performance water reducing agent with respect to 100 parts by weight of the total mixture of super-hard cement and fly ash. 4 parts by weight.
By using the high performance water reducing agent in such a blending amount, the fluidity at the time of injection of the injection material of the present invention can be ensured satisfactorily.

In addition, since the ultrafast cement is mixed in the injecting material of the present invention for early strength development, etc., the setting time is mixed with the injecting material for the open particle size mixture, and the working time for injecting cement milk is reduced. Secure.
As the setting retarder used in the present invention, a mixture of an alkali metal carbonate such as potassium carbonate or sodium carbonate and an organic acid such as citric acid or tartaric acid can be used. It is appropriate to use a lignin retarder and an oxycarboxylic acid retarder in combination.
By using the two kinds of retarders in combination, the fluidity can be maintained well, and the influence on the strength development in a short time is small, and the object of the present invention can be effectively achieved.

  The blending amount is 0.2 to 1.2% by weight, preferably 0.3 to 1.0% by weight, oxycarboxylic acid, based on 100 parts by weight of the super-hard cement and fly ash A system retarder of 0.01 to 0.30% by weight, preferably 0.01 to 0.20% by weight, is particularly effective for maintaining high fluidity while ensuring early strength development. .

  The injection material for an open particle size mixture of the present invention includes, for example, ultrafast cement, powder fly ash, calcium carbonate as needed, high performance water reducing agent, lignin retarder and oxycarboxylic acid retarder as described above. Prepared by dry mixing with a conventional powder mixing device such as a V-type mixer in advance at the compounding amount, and knead them uniformly with water and a mixer when used in the field, or a liquid high performance It is also possible to dilute the water reducing agent in water and knead it with other materials to prepare cement milk.

The amount of water added is 45 to 60 parts by weight, preferably 45 to 55 parts by weight with respect to 100 parts by weight of the injection material for open particle size mixture of the present invention.
If the amount of water added is larger than the above-mentioned amount, the flow value is reduced and the pouring property is improved. However, this is not preferable because the physical properties are lowered, and if it is within the above range, the P funnel (“consistency of prepacked concrete pouring mortar This is because the flow value according to “Test Method” (Japan Society of Civil Engineers) is about 8 to 13 seconds, which is preferable from the viewpoint of fluidity.

  A semi-flexible structure is constructed by pouring the obtained cement milk into an existing open grain size mixture structure such as an existing open grain asphalt layer or asphalt concrete layer. The semi-flexible structure is, for example, a structure in which an open-graded asphalt mixture having a porosity of 20 to 28% is laid and then impregnated with cement milk for infiltration into the void (Japan Road Association, asphalt pavement outline) Can be illustrated.

The amount of cement milk supplied to the semi-flexible structure, which is an open particle size mixture, is slightly larger than the theoretical void amount of the open particle size mixture structure matrix, and is sufficiently penetrated into the gaps between the open particles. It is desirable to construct as follows.
Since the injection material for an open particle size mixture of the present invention has good filling properties, the injection operation can be performed without vibration, particularly if the open particle size mixture is free from void clogging or crushing.

Preferably, immediately after the cement milk is injected into the mother body of the open particle size mixture structure, fine aggregates such as silica sand can be sprayed on the surface to suppress slippage.
Various types of silica sand such as river sand and mountain sand can be used, but it is particularly preferable to use relatively fine silica sand, preferably 0.2 to 1.0 kg / m ² (preferably 0.4 to 0). .7 kg / m ² ).
Further, finishing work such as shot blasting or polishing finishing may be performed as necessary.

The invention is illustrated by the following examples, comparative examples and test examples.
The following materials were used in each example and comparative example.
<Materials used>
Injectable cement composition for open particle size mixture / Super fast cement: Brand name Jet cement (Sumitomo Osaka Cement Co., Ltd.)
・ Fly ash (classified to 20 μm or less): Product name Finalash FA20 (manufactured by Sidden Industry Co., Ltd.)
・ High-performance water reducing agent (Naphthalenesulfonic acid high condensate): Product name Mighty 100 (manufactured by Kao Corporation)
・ Lignin retarder: Trade name Pozzolith No. 8 (Made by Pozoris Co., Ltd.)
・ Oxycarboxylic acid retarder (citric acid): Trade name Jet Setter (Sumitomo Osaka Cement Co., Ltd.)
・ Calcium carbonate powder: Trade name LP-200 (Omi Mining Co., Ltd.)
・ Re-emulsifying powder resin: (trade name Sumikaflex RP100S (manufactured by Sumitomo Chemical Co., Ltd.)
・ Silica sand No. 4 (manufactured by Sankyu Shipping Co., Ltd.)

Examples 1-4, Comparative Examples 1-9 (injection material for open particle size mixture)
In the blending ratio shown in Table 1 below, the above super-hard cement, fly ash, high-performance water reducing agent, lignin retarder, calcium carbonate powder, re-emulsifying powder resin, and silica sand No. 7 are mixed in advance, and one powder type cement A composition was prepared.
Next, each cement composition obtained and water in which an oxycarboxylic retardant was dissolved in advance were stirred and mixed with a hand mixer for 2 minutes to prepare cement milk as an injection material for an open particle size mixture. Cement milk was prepared by adding water to each cement composition so that the mixing ratio of water was 45%.
The P funnel flow time and the compressive strength after cement milk construction of each obtained cement milk were measured, and the results are shown in Table 1.
・ P funnel flow time: "Consistency test method for mortar of pre-packed concrete" (Japan Society of Civil Engineers)
Compressive strength: Compressive strength after 3 hours and 7 days of age was measured according to “Physical test method for cement” (JIS R 5201).

  No. 4 silica sand (manufactured by Sankyu Shipping Co., Ltd.) adjusted to a thickness of 5 cm was used as a simulated specimen for an open particle size mixture layer, and cement milk of each of the obtained open particle mixture mixture was injected into the simulated specimen. The cement milk was infiltrated with a simulated specimen and cured and cured.

In Table 1, the injection rate of each cement milk into silica sand No. 4 (open particle size mixture layer) and the compressive strength after curing and curing are values measured by the following methods.
・ Injection rate: Since the silica sand No. 4 in the cement milk uninjected part can be easily removed when removed from the formwork, spread the No. 4 silica sand to a thickness of 5 cm, pour the cement milk into the No. 4 silica sand and harden Thereafter, the injection rate was determined from the amount of uninjected sand.
Injection rate (%) = (weight of silica sand 4 before injection−weight of silica sand 4 of uninjected portion) / weight of silica sand 4 before injection × 100

From Table 1, in Examples 1 to 3 using the cement composition of the present invention, due to the addition effect of classified fly ash, the injectability is good. In particular, in Example 1, the strength expression is also No. 7 silica sand. In Example 2, the strength is slightly reduced in Example 2 because the amount of cement to be blended is small, but such a decrease in strength does not cause any particular problem in practice. In Example 3, since the amount of classified fly ash to be blended is small, the injectability is slightly deteriorated, but there is no particular problem in practical use.
In Example 4, by replacing the classified fly ash with 12% by weight of calcium carbonate powder, the injectability is slightly reduced, but there is no particular problem in practical use. Compared with Example 1, the strength can be increased. I understand that.

In Comparative Examples 3, 4 and 5, since the re-emulsifying resin is blended in the cement composition, the injection rate is small. In particular, in Comparative Examples 4 and 5, the P funnel flowing time of the used cement milk is carried out. Although it is comparable to Examples 1-4, it turns out that an injection rate is bad.
Further, Comparative Example 6 using a cement composition not containing fly ash and containing calcium carbonate powder has a P funnel flow time similar to that of the example, but the injection rate is poor, and a lignin retarder is used. In Comparative Example 7 which was not blended, the P funnel flow time was delayed, and the injection rate was also reduced.
In Comparative Example 9, when the classified fly ash is replaced with calcium carbonate powder in an amount of 15% by weight, the injectability is significantly reduced.

Examples 5 to 9 and Comparative Examples 10 to 11 (workability)
Except for changing the water cement ratio to the ratio shown in Table 2, each cement milk was prepared in the same manner as in Example 1, and the P funnel flow time, injection rate, compressive strength, and breathing were evaluated and measured. Is shown in Table 2.
The P funnel flow time, the injection rate, and the compressive strength were evaluated by the same test method as in Example 1, and the breathing was evaluated visually.
・ Breathing: Small 0-2%
2% or more

In Examples 5, 6, and 7, the injection property to the simulated specimen is good, and the strength expression decreases as the water cement composition ratio increases, but there is no particular problem in practical use.
In Comparative Example 10, the water cement composition ratio is small and the strength development and breathing are good, but the injection property to the simulated specimen is poor.
Further, in Comparative Example 11, it can be seen that the injection property to the simulated specimen is good, but the strength development property is poor, the breathing is large, and there is a tendency of material separation.

Examples 8 to 10 and Comparative Examples 12 to 13 (slip resistance when injected into existing drainage pavement)
Using the cement composition of Example 4, cement milk having a water cement composition ratio of 55% was poured into the existing drainage pavement, and immediately after that, silica sand No. 7 (manufactured by Sankyu Shipping Co., Ltd.) was used in the amount shown in Table 3. The slip resistance was evaluated by spraying. The results are shown in Table 3.
・ Slip resistance test: “Measurement method of slip resistance of paved road surface (method using pendulum skid resistance tester)” (Pavement Test Method Handbook)

実施例８、９、１０においては、細骨材の散布効果により、すべり抵抗値は高く、一方、比較例１２においては、細骨材が散布されていないため、すべり抵抗値が低く、また、比較例１３においては、細骨材散布量が多いため、すべり抵抗値は高いが余剰分が飛散し、環境的に好ましくないことがわかる。

In Examples 8, 9, and 10, the sliding resistance value is high due to the dispersion effect of fine aggregate, while in Comparative Example 12, since the fine aggregate is not dispersed, the sliding resistance value is low, In Comparative Example 13, since the amount of fine aggregate sprayed is large, the slip resistance value is high, but the surplus is scattered, which is environmentally undesirable.

The injection material for open particle size mixture of the present invention can be effectively applied to semi-flexible structures such as open particle size asphalt paved roads, open particle size asphalt concrete paved roads, gas stations, bus stops, parking lots and playgrounds. In particular, it can be effectively applied in environments where noise is an important issue, such as night work and indoor work.

Claims (4)

  High-performance water reducing agent is added to 100 parts by weight of the cement and fly ash mixed material having a blending ratio of 50 to 80% by weight of super-hard cement and 20 to 50% by weight of fly ash classified to 20 μm or less. -1.6 parts by weight, 0.2 to 1.2 parts by weight of lignin-based retarder and 0.01 to 0.30 parts by weight of oxycarboxylic acid-based retarder, Injection material for mixture.   The injection material for open particle size mixture according to claim 1, wherein 12% by weight or less of the blending amount of fly ash with respect to the super-hard cement is replaced with calcium carbonate powder.   A cement milk is prepared by mixing 45 to 60 parts by weight of water with 100 parts by weight of the injectable material for open particle size mixture according to claim 1 or 2, and then the cement milk is injected and supplied to the open particle size mixture structure. A method for constructing a semi-flexible structure, comprising the step of allowing the supplied cement milk to penetrate into the voids of the open particle size mixture structure. The method for constructing a semi-flexible structure according to claim 3, further comprising a step of spraying fine aggregate in an amount of 0.2 to 1.0 kg / m ² after injecting and supplying cement milk. Construction method for flexible structures.