JPH03295905A - Powder-like polymer cement composition for semi-difflection pavement and application method thereof - Google Patents

Abstract

PURPOSE:To shorten the time of application by injecting cement milk which is prepared by mixing a material composed of cement, flyash, quartz sand and re-emulsified powder-like polymer, powder-like additive, into asphalt concrete. CONSTITUTION:20 parts of quartz sand 20, with respect to 100 parts of Portland cement, 40 parts of flyash are taken into a universal kneader for agitating them at a low speed for 10 minutes. Then, thus obtained blend is added thereto with 2.6 parts of ethylene vinyl acetate resin, as re-emulsified powder-like polymer, together with 0.8 parts of water reducing agent and 0.2 parts of deforming agent, and thereafter, it is agitated at a high speed for 20 minutes so as to prepare a blended powder material. Next, the blended powder material is added with 40 parts of water, and is agitated at a low speed for 5 minutes so as to obtain grout which is then injected gaps among aggregates in asphalt concrete having an open particle size corresponding to voids of 22%. Thereby it is possible to obtain a pavement having a flexibility and a rigidity.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a semi-flexible pavement that is simple, free from mixing errors, has excellent workability, and has a good finish when constructing semi-flexible pavement for roads. The present invention relates to a single powder type polymer cement composition and a method for constructing semi-flexible pavement using the powder type polymer cement composition.

[Conventional technology]

Conventionally, the Salvia Sim method (equity method 4O-3504) and Polyseal method (equity method 4O-3504), which are called semi-rigid pavement methods, are
In the Japanese Patent Publication No. 43-4696), cement milk used as grout was prepared by adding powder such as cement or crushed sand to a mixture of resin emulsion or rubber latex and water while stirring it in advance at a road paving site. A method of injecting this into open-grained asphalt concrete is known. These methods compensate for the drawbacks of asphalt concrete pavement and cement concrete pavement, and are attracting attention as flow-resistant pavement. Particularly in metropolitan areas, increased traffic volume causes ruts and damage, and the need for pavement resistance to flow is increasing.

[Problem to be solved by the invention]

The above-mentioned pavement construction methods in metropolitan areas have to be carried out at night or within short-term traffic regulations in order to ensure the traffic function, which is the primary function of roads. , it is necessary to complete the process from laying open-grained asphalt concrete to grouting within the specified time.

However, in the conventional semi-flexible pavement construction method, several types of compounded materials are measured and mixed at the work site, and the time required for this cannot be ignored. Furthermore, the measuring and mixing work often relies on the labor of inexperienced workers, and there is a high risk of mixing errors.

In order to improve these to some extent, efforts have been made to introduce rental cars, but it is not perfect, and in some cases deviations from the basic mix may occur. In particular, when using a rapidly hardening cement, deviation from the basic formulation tends to increase the viscosity of the grout.

As a result, the permeability into the voids of the open-grained asphalt concrete pavement is insufficient, making it impossible to obtain a pavement that has both flexibility and rigidity as intended by this construction method. Furthermore, due to the increase in viscosity, the finished product may not be completely satisfactory.

[Means to solve the problem]

In view of the above circumstances, the present inventors have investigated various simple construction methods that allow grout to penetrate into the voids of an open-grained asphalt concrete pavement within the shortest possible time and that prevent mixing errors at the construction site. As a result, we have arrived at the present invention.

That is, the semi-flexible one-powder type polymer cement composition for pavement of the present invention is prepared by mixing and adjusting constituent materials including cement, fly ash, silica sand, re-emulsifiable powder polymer, and optionally powder additives. It is characterized by

In addition, the construction method of the one-powder type polymer cement composition for semi-flexible pavement of the present invention includes mixing and adjusting constituent materials including cement, fly ash, silica sand, liturgical powder polymer, and powder additives if desired. The present invention is characterized in that a polymer cement grout obtained by adding water to a single-powder type polymer cement composition and stirring and mixing the composition is injected into the gaps between aggregates of open-grained asphalt concrete.

The present invention will be explained in detail below.

(Composition) Examples of the re-emulsifiable powder polymer used in the present invention include commercially available vinyl acetate polymers. Examples include ethylene vinyl acetate street resin, carboxylic acid-modified vinyl acetate resin, Beova-modified vinyl acetate resin, vinyl acetate-acrylic acid ester copolymer, etc., and these can be used as they are.

Examples of the cement include ordinary Portland cement, early-strengthening cement, ultra-early-strengthening cement, various quick-hardening cements, white cement, and various colored cements.

For urgent road repairs that need to be completed in a short time, it is necessary to speed up the hardening of cement, and in this case, quick-hardening cement can be used, and different types of cement can be used depending on the purpose and use. When using fast-setting cement, a setting retarder (setter) may be used.

As the silica sand, it is preferable to use relatively fine silica sand of about No. 7 size. In the present invention, good results have been obtained using No. 7 silica sand. In place of silica sand, granulated slag generated in steel mills may be used, or may be used in combination. In addition, it is good to mix fly ash in order to improve fluidity. As other powder additives, water reducing agents, fluidizing agents, antifoaming agents, etc. can also be added.

Next, the amounts of various components and the mixing method will be explained.

10 to 60 parts of silica sand, preferably 15 to 60 parts by weight of Portland cement (hereinafter simply referred to as parts)
Add 50 copies. Relatively fine silica sand of size 6 to 8 is used as the silica sand. Instead of silica sand, the same amount of granulated slag generated in steel mills may be used, or the same amount may be used in combination. In addition, 15 to 70 parts, preferably 20 to 50 parts of fly ash is mixed in to improve fluidity.

The amount of the recirculating powder polymer is in the range of 0.5 to 10 parts, preferably 1 to 8 parts per 100 parts of cement, and adding more than this will not significantly improve the physical properties. Rather, it only increases viscosity and cost. (Figure 1
Reference) In order to improve the injectability as a grout, lower the viscosity,
It is necessary to reduce the flow value, and in the semi-flexural paving method, the flow value is generally adjusted to 10 to 14 seconds. The flow value can be reduced by increasing the amount of water, but this will reduce the physical properties of the mortar, so it is preferable to use a general fluidizing agent as a water reducing agent for cement concrete, and the amount should be 2 parts or less, More preferably, 0.05 to 1.5 parts are used. Also, when adding water at the end at the construction site, there is a risk of getting air involved.
0.05 to 0.4 part of powdered antifoaming agent, preferably 0.1 part
It is recommended to add ~0.3 part.

For color paving, use an inorganic coloring agent such as red iron.
~4 parts can also be added. In this case, if you want a brighter finish, it is better to use white cement instead of ordinary Portland cement.

Road paving work often involves repair and renovation work.
In the semi-flexible pavement method, it is also possible to use grout containing the one-powder type polymer cement composition of the present invention as an active ingredient. However, in the case of repair work, it is necessary to open the road to traffic as soon as possible, as the road is currently in shared use. To do this, it is necessary to speed up the hardening of cement.
In this case, instead of ordinary Portland cement, a quick-hardening cement, an ultra-early-strengthening cement, or a rapidly hardening cement is used. In this case, these can be used alone or in combination with ordinary Portland cement. When using rapid hardening cement, a setting retarder (setter) may be used. Ordinary Portland cement may be used and a hardening accelerator may be added to speed up hardening.

Mixing of these powders does not require any special equipment, and a boat-mounted powder mixing device (for example, a ■-type mixer, a vertical ■-type mixer, a universal mixer, etc.) is used.

The thus obtained mixed powder is filled into a moisture-proof paper bag commonly used for cement, stored in a sealed container, and shipped to the construction site if necessary.

[Construction method]

The method for constructing semi-flexible pavement using a single-powder type polymer cement composition according to the present invention uses the above-mentioned powder-type polymer cement composition. Only 20 to 60 parts, preferably 25 to 50 parts of water are used per 100 parts of water (referred to as body), and no special machinery is required.

A conventional mixing and stirring device can be used as is.

Injection of the finished polymer cement grout can also be performed using conventional mechanical equipment and conventional construction methods.

The present invention will be explained in more detail with reference to Examples below. In addition, in Examples and Comparative Examples, parts and % refer to parts by weight and % by weight.

Example 1 (Preparation of ready-mixed powder) 100 parts of Portland cement, 20 parts of crushed sand, and 40 parts of fly ash were placed in a container of a universal mixer, a stirring blade was attached, and the mixture was initially stirred at low speed for 10 minutes.

Then, as a re-emulsifiable powder polymer, 3.6 parts of ethylene vinyl acetate resin, 0.8 parts of a water reducing agent and 0.8 parts of an antifoaming agent were added.
2 parts were added and the mixture was stirred and mixed for 20 minutes at a high stirring speed to produce a ready-mixed powder, which was stored in a sealed container.

(Preparation of base asphalt) The base asphalt to be injected has a porosity of 22% and is made by blending 3.8% of paving asphalt with a penetration degree of 60 to 80 to open-grained aggregate having the particle size distribution shown in Table 1. Open-grained asphalt concrete was used, which was leveled and compacted using a pre-prepared formwork to a size of 30 x 30 cm and a thickness of 5 cm.

(Injection of grout) Take out 100 parts of the ready-mixed powder prepared above from the airtight container, put it in a mortar mixer, add 40 parts of water,
Stir and mix at low speed for 5 minutes.

When the flow value of this product was measured, it was grouted in 12 seconds and showed appropriate properties.

The grout thus prepared was injected into the base ascon, and spread using a rubber rake, allowing complete penetration without vibration.

The physical properties of the pavement and grout thus obtained were as shown in Table 2.

Table 1 Particle size distribution of open-grained aggregate Example 2 (Preparation of ready-mixed powder) To 100 parts of quick-hardening cement, 30 parts of silica sand, 40 parts of fly ash, and 0.2 parts of setting retarder were added to a container of a universal mixer. The mixture was stirred for 10 minutes in the same manner as in Example 1.

Next, as a re-emulsifiable powder polymer, 3.8 parts of Beova-modified vinyl acetate resin, 0.1 part of a water reducing agent, and 0 part of an antifoaming agent were added.
．． 2 parts and prepared in the same manner as in Example 1,
Stored in an airtight container.

(Injection of grout) Take out 100 parts of the ready-mixed powder prepared above from the airtight container, put it in a mortar mixer, add 40 parts of water,
Mix by stirring at low speed for 4 minutes.

When the flow value of this product was measured, it was grouted in 12 seconds and showed appropriate properties.

The grout thus prepared was injected into a base ascon made in the same manner as in Example 1, spread using a rubber rake, and completely penetrated without vibration.

The physical properties of the pavement and grout thus obtained were as shown in Table 2.

Example 3 (Preparation of ready-mixed powder) 100 parts of Portland cement, 20 parts of silica sand, and 25 parts of fly ash were placed in a container of a universal mixer, and stirred for 10 minutes in the same manner as in Example 1.

Then again! A FL-formable powder polymer was prepared in the same manner as in Example 1 by adding 3.2 parts of carboxylic acid-modified vinyl acetate resin and stirring for 20 minutes, and stored in a closed container.

(Injection of grout) 100 parts of the ready-mixed powder prepared above was taken out from the airtight container, put into a mortar mixer, 40 parts of water was added, and the mixture was stirred and mixed at low speed for 4 minutes.

When the flow value of this product was measured, it showed properties suitable for grout in 11 seconds.

The grout thus prepared was injected into a base ascon made in the same manner as in Example 1, spread using a rubber rake, and completely penetrated without vibration.

The physical properties of the pavement and grout thus obtained were as shown in Table 2.

Comparative Example 1 (Preparation of ready-mixed powder) 100 parts of Portland cement, 20 parts of silica sand, and 40 parts of fly ash were placed in a container of a universal mixer, a stirring blade was attached, and the mixture was first stirred at low speed for 10 minutes. ?
- was prepared and stored in an airtight container.

(Injection of grout) Take out 100 parts of the ready-mixed powder prepared above from the airtight container, put it in a mortar mixer, add 40 parts of water,
Mix by stirring at low speed for 4 minutes.

When the flow value of this grout was measured, it took 12 seconds, and it showed suitable properties as a grout.

The grout thus prepared was injected into a base ascon made in the same manner as in Example 1, spread using a rubber rake, and completely penetrated without vibration.

The physical properties of the pavement and grout thus obtained were as shown in Table 2.

Comparative Example 2 (Preparation of ready-mixed powder) 20 parts of silica sand per 100 parts of Portland cement,
40 parts of fly ash was placed in a container of a multipurpose mixer, a stirring blade was attached, and the mixture was stirred and mixed at low speed for 100 minutes at first, to form a powder to which no polymer was added, and the powder was stored in an airtight container.

(Injection of grout) 100 parts of the ready-mixed powder prepared above was taken out from the airtight container, put into a mortar mixer, 35 parts of water was added, and then 8 parts of styrene-butadiene rubber latex was added as a polymer, and the mixture was stirred for 5 minutes. .

When the flow value of this grout was measured, it was found to be 11 seconds, and showed suitable properties as a grout.

The grout thus prepared was injected into a base ascon made in the same manner as in Example 1, spread using a rubber rake, and completely penetrated without vibration.

The physical properties of the pavement and grout thus obtained were as shown in Table 2.

Comparative Example 3 (Preparation of grout) 70 parts of water was placed in a mortar mixer, 10 parts of styrene-butadiene rubber latex was added, and the mixture was initially stirred at low speed for 1 minute.

Next, 100 parts of Portland cement, 50 parts of fly ash, and 40 parts of silica sand were added in this order, the stirring speed was increased to high speed, and the mixture was stirred and mixed for 5 minutes to prepare a grout.

When the flow value of this grout was measured, it was found to be 11 seconds, and showed suitable properties as a grout.

(Injection of grout) Take out the grout prepared above from the mixer,
It was injected into a base ascon manufactured by the same method as in Example 1, and spread using a rubber rake to allow complete penetration without vibration.

The physical properties of the grout and pavement thus obtained were as shown in Table 2.

Table 2 Physical properties of grout and pavement Construction test Open-grain asphalt concrete having the particle size distribution shown in Table 1 was paved outdoors using an actual construction machine.
100 parts of ready-mixed powder for injection prepared by the same formulation and method as in Example 1 and stored in a paper bag was taken into a mortar mixer, 40 parts of water was added, stirred and mixed for 5 minutes, and then poured. It was spread using a vibrating roller, and thoroughly penetrated using a vibrating roller. At that time, the time required to prepare the grout, permeability, etc. were measured, and subsequent progress was observed.

Similarly, outdoors, a grout having the composition shown in Comparative Example 3 was prepared at the construction site, poured into the same base ascon as above, and sufficiently penetrated in the same manner. etc., and subsequent follow-up observations were made. These results are shown in Table 3.

Table 3 Construction test results [Effects of the invention] As explained above, the present invention not only eliminates the risk of mixing mistakes when preparing grout at the construction site, but also eliminates the possibility of mixing mistakes when preparing grout at the construction site. The effects of quick-hardening cement used in road repair work can be kept to a minimum. The time required for stirring and mixing is important, especially in the summer, as there is a risk of curing too quickly.
A mixing error in the case of the quick-setting type not only impairs the performance of the pavement, but also causes the grout to harden in the mortar mixer, injection hose, etc. due to rapid hardening, causing problems in the work. The present invention solves these conventional problems.

Furthermore, as shown in Tables 2 and 3, the performance of the semi-flexible pavement of the present invention is not significantly inferior to that of the conventional construction method using latex emulsion, and meets the specifications of government agencies. do.

This can be said to be an extremely effective composition and construction method in order to deal with the shortage of people on site, which is expected to become more and more serious in the future.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the amount of re-emulsifiable powder polymer blended, viscosity, and bending strength.

Claims (2)

[Claims] (1) A cement composition for preparing cement milk used as grout in the semi-flexible pavement method for road pavement, which includes cement, fly ash, silica sand, re-emulsifiable powder polymer, and powder added if desired. 1. A semi-flexible one-powder type polymer cement composition for pavement, characterized by being made by mixing and adjusting constituent materials including an agent. (2) When using cement milk as a grouting material in the semi-flexural paving method for road paving,
The feature is that a polymer cement grout prepared by adding water to a one-powder type polymer cement composition prepared by the formulation described in claim 1 and stirring the mixture is injected into the aggregate gaps of open-grained asphalt concrete. A construction method for a single-powder type polymer cement composition for semi-flexible pavement.