KR20090018542A - Concrete composition for aggregate exposed road pavement and construction method of aggregate exposed concrete pavement using the same - Google Patents

Abstract

The present invention relates to a concrete composition for paving aggregates exposed to the road, including cement, fine aggregates, coarse aggregates, among coarse aggregates, coarse aggregates having a particle size of 9.5 to 13.2 mm are larger than coarse aggregates having a particle size of 2.36 to 4.75 mm. By presenting the concrete composition for paving the aggregate exposed road, characterized in that a large number of coarse aggregates are exposed to the pavement surface with a high adhesion strength, it is possible to obtain a good quality aggregate exposed concrete pavement structure.

Description

COMPOSITION FOR EXPOSED AGGREGATE CONCRETE PAVEMENT AND CONSTRUCTION METHOD FOR EXPOSED AGGREGATE CONCRETE PAVEMENT USING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of civil engineering, and more particularly, to a construction method of pavement for reducing the occurrence of noise.

Concrete road pavement is being actively constructed on the highway in consideration of durability and economic feasibility compared with asphalt pavement to solve the difficulty of maintenance due to plastic deformation and breakage of asphalt.

Concrete pavement has been reported to have good bearing capacity for heavy vehicles and long-term commonality.

However, concrete pavement improves concrete pavement due to the high level of service demand for low noise and riding comfort of road users due to the disadvantage of 4 ~ 6dB (A) noise and poor driving performance compared to asphalt pavement compared to asphalt pavement. This situation is required.

In road pavement, skid resistance between the tire and the road surface plays an important role in driving safety as a basic factor controlling the braking distance.

In other words, the road pavement surface should ensure the appropriate level of slip resistance of the tires and road pavement surface of the car to provide driver safety in the movement of the cars.

In particular, when the surface of the road is wet in the rainy weather, when the hydroplaning occurs, the sliding resistance is reduced, resulting in a high traffic accident rate.

It is reported that 25% of traffic accidents are caused by unslip resistance when the road surface is wet in rainy weather, and 13.5% of them are the cause of fatal accidents (Cheliah et al., 2002).

Domestic concrete pavement has mainly used lateral tying as a surface treatment method to secure slip resistance and prevent water film during rainy weather, which provides a high level of slip resistance for a long time, but it is caused by noise between pavement and tires. There is a problem that noise occurs.

In this situation, as one of the surface finishing methods to secure the noise and slip resistance of concrete pavement, the concrete mortar is decomposed and coarse aggregates are exposed to the pavement surface without any additional surface structure on the pavement surface. Aggregate-exposed concrete pavement techniques have emerged to form the proper texture.

Aggregate exposed concrete pavement reduces noise generated between tires and road surfaces, and in particular, minimizes whine in various patterns and maintains long-term slip resistance to secure driving safety and prevent slipping of vehicles. Reports and actual cases of construction are being reported through the US Federal Bureau of Road, the Japan Road Authority, and the PIARC Meeting in Europe (Lee Woong-se et al., 2000).

In particular, in the aggregate exposure method, the smaller the size of the aggregate, the greater the noise reduction effect and the sliding resistance.

In addition, the pavement surface by the aggregate exposure method has the advantage that the whine phenomenon can be minimized because the aggregate is exposed in a variety of patterns, rather than the formation of a regular interval such as transverse tying.

However, the aggregate exposure method is not a technically easy method. The reason for this is that in order to form the intermediate tissue, which is the surface tissue form which is the best in noise and slip resistance, on the surface, a compound design considering the strength, slip resistance and noise must be carried out.

In order to satisfy these conditions, the construction method is difficult because the construction method according to the mixing design of concrete, delayed spraying, construction sequence such as aggregate exposure work, and proper construction equipment must be thoroughly followed.

For this purpose, when mixing concrete materials for applying the aggregate exposure method, it is necessary to increase the coarse aggregate volume ratio so that many coarse aggregates are uniformly exposed on the surface.

In order to maintain the noise reduction effect and long-term slip resistance, an appropriate amount of mean tissue depth (MTD) and aggregate exposure should be obtained.

This is because when the coarse aggregate volume ratio is small, the aggregate is exposed unevenly and the average tissue depth is large, and when it is too large, the exposure is too low and the average tissue depth is not obtained.

However, in the past, due to the demanding construction method in Korea, studies on such specific compounding designs have been insufficient. As a result, the aggregate exposure packaging method has been pointed out as a problem.

The present invention has been made to solve the above problems, the aggregate exposure road to obtain a good quality aggregate exposed concrete road pavement structure by allowing a large number of coarse aggregate is exposed to the pavement surface with a high adhesion strength. The purpose of the present invention is to propose a construction method for concrete pavement and pavement exposed concrete road pavement using the same.

The present invention, in order to achieve the object as described above, in the concrete composition for paving the road exposure aggregate, including cement, fine aggregate, coarse aggregate, among the coarse aggregate, the coarse aggregate having a particle size of 9.5 ~ 13.2 mm is 2.36 ~ 4.75 It proposes a concrete composition for paving aggregate exposure road, characterized in that a large amount compared to the coarse aggregate is mm.

Among the coarse aggregate, the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm is preferably 1: 1 to 3: 7.

Among the coarse aggregate, the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm is preferably 4: 6.

Among the coarse aggregate, 40% by weight is preferably included in the coarse aggregate having a particle size of 4.75 ~ 9.5 mm.

The present invention is another means for achieving the above object, that is, the construction method of the aggregate exposed concrete road pavement using the concrete composition for the pavement exposed road, the penetration resistance stress of concrete is 1000 kgf / cm ² From the time point of occurrence, after the concrete pouring, 30 hours, the construction of the aggregate exposed concrete road pavement, characterized in that the aggregate surface is exposed by scraping the surface of the concrete.

The present invention allows a large number of coarse aggregates to be exposed to the pavement surface with high adhesion strength, thereby obtaining an aggregate exposed concrete road pavement structure of good quality.

The present invention basically relates to a concrete composition for paving aggregates, including cement, fine aggregates, coarse aggregates, coarse aggregates of coarse aggregates, 9.5 ~ 13.2 mm of coarse aggregates are larger than coarse aggregates having a particle size of 2.36 ~ 4.75 mm It is characterized by the included.

That is, in the aggregate exposed concrete pavement, in order for a large number of coarse aggregates to be uniformly exposed on the pavement surface, the coarse aggregate volume ratio should be increased.

Hereinafter, an experimental example for supporting this will be described in detail.

The formulation used is shown in Table 1, and the average temperature in the experiment is 11.5 ℃ and 57.7% humidity.

Water / Cement Ratio W / C (%) Fine Aggregate S / a (%) Unit weight (kg / m ³ ) W C S G AE 45 30 150 333.3 536 1262 C × 0.1%

Based on the coarse aggregate particle size standard of pavement concrete, the maximum coarse aggregate size for aggregate exposed concrete packaging was determined to be 13.2mm, and the optimum mix design was carried out through the particle size design. .

As a result of the mixing, the air volume was 4% and the slump value was 1 cm.

While the amount of aggregate of 4.75 to 9.5 mm particle size is kept constant, while the sum of the amounts of aggregate of 2.36 to 4.75 mm particle size and 9.5 to 13.2 mm particle size is constant, The physical properties of aggregate exposed concrete pavement such as, exposure, BPN and MTD were measured.

The reason for setting the premise of the experiment is that, in the concrete composition for aggregate exposure road pavement, the aggregate that most influences the physical properties is known to be aggregate of 2.36-4.75 mm particle size and 9.5-13.2 mm particle size.

A total of seven specimens were prepared. Three specimens were prepared for each variable, varying the aggregate size from 9.5 to 13.2 mm to 10, 20, 40, 50, 60, 70, and 100% by weight. Is shown in Table 2 (the aggregate amount of 2.36 ~ 4.75 mm particle size is 90, 80, 60, 50, 40, 30, 0% by weight).

Particle size (mm) Coarse aggregate content (kg) 10% 20% 40% 50% 60% 70% 100% 2.36-4.75 adjustment 681.48 605.76 454.32 378.6 302.88 227.16 0 4.75-9.5 40% fixed 504.8 504.8 504.8 504.8 504.8 504.8 504.8 9.5 ~ 13.2 adjustment 75.72 151.44 302.88 378.6 454.32 530.04 757.2

After performing the aggregate exposure for each of these specimens, the measured values of the pavement structure are as follows.

Experiment variable 10% 20% 40% 50% 60% 70% 100% MTD (mm) 2.1 2.0 2.0 2.0 1.8 1.9 1.4 BPN 74.0 75.2 77.0 78.2 80.1 77.6 75.1 Exposure degree (dog / 25㎠) 12.2 12.9 13.9 17.6 21.8 18.9 22.8 SN 58.5 59.0 60.8 61.6 61.9 60.5 56.0

In the above table, Mean Texure Depth (MTD) means the average tissue depth of the aggregate exposure pavement, the number of exposures means the number of aggregates exposed on the pavement surface, and SN ₄₀ means the slip resistance of the pavement.

Experimental results show that when the coarse aggregate with particle size of 9.5 ~ 13.2 mm is included in large amount compared to the coarse aggregate with particle size of 2.36 ~ 4.75 mm (the content of coarse aggregate of 9.5 ~ 13.2 mm is more than 50%), It can be seen that the comparatively excellent physical properties appear, especially the ratio of coarse aggregates having a particle size of 2.36 to 4.75 mm and coarse aggregates having a particle size of 9.5 to 13.2 mm is in the range of 1: 1 to 3: 7 (coarse aggregates having 9.5 to 13.2 mm). 50 to 70%) can be seen that the best physical properties appear.

That is, when the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm is within the above range, the MTD has a value of 2 mm or less in the above range (Table 5), but is larger than the range. It can be seen that when the MTD is 2 mm or more and small, the size is significantly smaller.

The BPN shows a high value of 80 or more in the range (Table 6), and thus the SN ₄₀ change also has the highest value in the range (Table 8), and if it is out of the range, it tends to decrease greatly. have.

In addition, looking at the change in the number of impressions (Table 7), it can be seen that as the coarse aggregate content increases, the number of exposure increases, but even if the aggregate content increases outside the above range, the change in the measured value is insignificant.

Therefore, the ratio of coarse aggregate with particle size of 2.36 ~ 4.75 mm and coarse aggregate with particle size of 9.5 ~ 13.2 mm is excellent in the range of 1: 1 ~ 3: 7 (when the content of coarse aggregate having 9.5 ~ 13.2 mm is 50 ~ 70%) It can be seen that the physical properties appear, in particular, the ratio of 4: 6 was confirmed that the most preferred.

As such, if the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm falls within the above range, the concrete composition is expected to have excellent physical properties, but the above experiment shows that the particle size is 4.75 to 9.5 mm. Phosphorous coarse aggregate is assumed to occupy 40% by weight of the total coarse aggregate, it is believed that even if the application in the actual formulation can be obtained a more certain effect.

For reference, the construction method of the aggregate exposed concrete road pavement as a premise of the concrete composition according to the present invention will be described.

After the concrete is poured (FIG. 1), the surface is finished to finish the surface of the poured concrete (FIG. 2), and the condensation retardant is sprayed on the concrete surface (FIG. 3).

After curing of the core of the concrete to some extent, the aggregate is exposed by scraping the surface of the concrete (Figs. 4 and 5).

On the other hand, during the construction of the aggregate exposure packaging method, the optimal time for the aggregate exposure work (scraping the surface of the concrete pavement) may be a problem, another test result, the penetration resistance stress of concrete 1000 kgf / cm ² From the time of occurrence of abnormality, it was found that the period after the concrete placement and before 30 hours passed was most suitable.

Here, the penetration resistance stress means a resistance of the concrete specimen to be measured when the penetration resistance load is applied to the specimen by the penetration resistance needle, as shown in FIG. 6, and therefore, the penetration resistance stress is small when the curing time is short. The longer the curing time is, the larger the hardening occurs and the larger the penetration resistance stress is measured.

Therefore, when measuring the penetration resistance stress of the concrete specimen, it is possible to know indirectly the degree of hardening of the poured concrete, it is possible to determine the optimal timing of the aggregate exposure work from it.

Since the above has been described only with respect to some of the preferred embodiments that can be implemented by the present invention, the scope of the present invention, as is well known, should not be construed as limited to the above embodiments, the present invention described above It will be said that both the technical idea and the technical idea which together with the base are included in the scope of the present invention.

1 to 6 are photographs for explaining the process of the construction method according to the present invention,

1 is a photograph of the concrete pouring step.

Figure 2 is a photograph of the surface finishing step.

Figure 3 is a photo of the coagulation delay agent spraying step.

Figure 4 is a photograph of the aggregate exposure step.

5 is a photograph of the surface of the package after the completion of construction.

Figure 6 is a photograph of the penetration resistance stress measurement step.

Claims (5)

In the concrete composition for paving aggregate exposure road including cement, fine aggregate, coarse aggregate, Among the coarse aggregate, the coarse aggregate having a particle size of 9.5 to 13.2 mm, the aggregate aggregate road paving concrete composition, characterized in that it contains a large amount compared to the coarse aggregate of 2.36 ~ 4.75 mm. The method of claim 1, Among the coarse aggregate, the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm is 1: 1 to 3: 7. The method of claim 2, Among the coarse aggregate, the ratio of the coarse aggregate having a particle size of 2.36 to 4.75 mm and the coarse aggregate having a particle size of 9.5 to 13.2 mm is 4: 6. The method according to any one of claims 1 to 3, Among the coarse aggregate, 40% by weight of the aggregate exposed concrete composition, characterized in that the coarse aggregate containing the coarse aggregate of 4.75 ~ 9.5 mm. As a construction method of aggregate exposed concrete road pavement using the concrete composition for paving aggregate exposed road, Penetration resistance stress of concrete is 1000 kgf / cm ² The construction method of the aggregate exposed concrete road pavement, characterized in that to expose the aggregate by scraping the surface of the concrete from the time of occurrence, after the concrete pouring, until 30 hours have elapsed.

Images