JPS63219703A - Execution of constructed soil requiring water permeability - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention provides a construction method for constructed soil that has water permeability as constructed soil, does not freeze up, has compressive strength and bending strength, and is suitable for various uses. This invention relates to the invention.

(Prior art and its problems) As a construction method for construction soil, the economical soil cement method is common.

This soil-cement construction method has a variety of uses, including roads with both rigid and deflecting pavement, streets, lower and upper bases of airports, and slopes that are subject to periodic and continuous flooding or wave action. The main areas are surface treatment, cores for earth dams, and linings for reservoirs.

The conventional soil cement method has not been applied to the above-mentioned sites, but it has been selected based on the usage, extremely large amount of cement is used, and water is tamped into the soil to achieve the optimum soil water content ratio. The main focus was on adjusting, mechanically compacting and curing to obtain compressive strength and bending strength.

Therefore, the construction soil obtained by the soil cement method is naturally non-permeable, and since it is applied to sites where it must be impermeable, soil cement methods that are permeable have not been considered until now. I had never done that before.

On the other hand, the softening of the ground surface caused by rainwater at sports stadiums, sidewalks, jogging courses, etc., has become a problem as it limits the time and period of use.

Recently, studies have also been conducted on the subbase course of sports stadiums constructed using artificial turf or artificial turf filled with dry sand.

Therefore, the inventor of the present invention developed the above-mentioned sports surf ace,
For the subbase of artificial grass, sidewalks, jogging courses, etc.
Color/Are you trying to apply the soil cement method? I was able to try.

However, it has been found that the soil cement method has a fatal drawback when used for the above-mentioned purposes.

Since it is originally impermeable, it has extremely poor permeability, secondly, it suffers from frost heave in areas where the temperature drops below freezing, and furthermore, the soil surface is destroyed by the cold.

The characteristic of soil cement is that if you try to increase its water permeability, the compressive strength will decrease, and if you try to increase the compressive strength, the water permeability will decrease, which is a contradictory relationship, and it is very difficult to solve the above drawbacks. It is.

In addition, among athletic fields, tennis clay courts are required to be water permeable, have appropriate bounce and cushioning, and have sufficient compressive strength; in this sense, they are the most difficult sports to surf. .

The present inventor is an engineer in the field of civil engineering and sports facilities, and is well aware that the various drawbacks of soil cement sports surfaces must be overcome, and that this is an extremely difficult task.

However, the low cost of soil constructed with soil cement is an even greater attraction, and the inventors of the present invention dared to take on the challenge described above, and have been conducting research for many years. We have now obtained new knowledge through research and experience, and have completed the present invention based on this new knowledge.

(Means for solving problems) The details of the configuration of the present invention will be explained below.

The soil used in the construction method of the present invention has a soil quality in the range of SL to LS according to the coordinates of the International Society of Soil Quality.

Soil in this range has the property of being easily mixed with hydraulic materials and easily increasing its compressive strength when compacted.

However, if the soil contains 5% or more of soil particles with a size of 105μ or less, it is called pre-treatment, and the soil and hydraulic material are mixed and coagulated, and the soil texture is in the range of SL to LS. An example of this case is to adjust the particle size to
By mixing 30-50% cement with 9% and leaving it for a day and night, the grain size can be adjusted to soil texture or soil in the range of SL-LS.

The term "hydraulic material" as used in the present invention refers to materials that harden with water, such as stone wax and lime, in addition to cement.

(Example) The optimum soil water content ratio for tamping soils in the range of SL to LS is approximately 6 to 15% on the S side and approximately 15 to 25% on the SL side.
%.

Soil tamping Optimum soil moisture content 1 m3 of soil with a soil moisture content of 17% is mixed with 100 kq of cement to achieve a soil moisture content of 21.7%, which is 1.28 times the soil moisture content or the optimum soil moisture content for soil tamping. After adjusting by sprinkling water and stirring, apply pressure 4 to 5 times with a roller, the water permeability coefficient is 4
Compressive strength is 17 kq/am at 10-' cm/sec
It was 2.

In addition, in this case, watering the soil may be done on a tree, or adding 9 to 1 m3 of soil with a synthetic resin emulsion]○~20 will further increase the compressive strength. What is important in this regard is that when hydraulic materials and soil are compacted at an optimum soil moisture content, they either have no compressive strength or are permeable; When compacted, water permeability is either good or the compressive strength is significantly reduced.

Furthermore, if soil is compacted at a soil water content ratio that is 1.5 times or more than the optimum soil water content ratio, both water permeability and compressive strength will decrease.

Therefore, by compacting the soil at a soil water content ratio that is 1.2 to 1.5 times the optimal soil water content ratio, it is possible to obtain a satisfactory compressive strength while maintaining good water permeability.

Next, explaining how to prevent frost heaving, it is generally said that soil has a frost heaving inhibiting effect if its compressive strength is 20 kq/cm2 or more.

In order to increase this strength, as described in the second invention, watering of about 1.5 to 2 I2/m2 is applied to the rolling pressure surface at least once within 7 to 21 days after the completion of compaction. If you do this, the water permeability will not change or the compressive strength will be 2.
It was possible to significantly increase the soil age to 9/cm2 at 28.0 days after 8 days of age.6 Therefore, it was possible to make the soil permeable to water and free from frost heaving.

Next, to explain the on-site construction method for the lower subgrade for tennis clay courts and sports stadiums with artificial turf, we first decide whether to build up the floor or dig the floor at the site, and then both build up the floor and dig the ground to a depth of about 30 cm. To explain the site of the inner bed filling, 0 to 40 mm of crushed stone or masago soil is spread to a thickness of 15 cm on the site and rolled with rollers.

Next, either bring soil 'i or good quality soil in the range of SL to LS to the site, or if you use a local engineer, investigate to see if more than 5% of the soil particles are 1050 or less. If the soil has a grain size of 0 or more, the particle size is adjusted with cement.The soil is compacted with crushed stones, etc., and then leveled in approximately 30 cm rows, and the cement is crushed at 100 kq/m3, and the soil and cement are separated using a tractor, etc. Mix. The soil water content ratio of this mixed soil is investigated, and the optimum soil water content ratio for soil compaction is 1.2 to 1.
．． Sprinkle 15 parts of ethylene acetate emulsion with 9 parts of water per 1 m3 of soil so that the volume is 5 times that of water, and stir the soil again with a tractor or the like. After that, 4 is temporarily rolled 2 to 3 times with a roller to correct unevenness, and then zero rolling is completed.

Once completed, the soil is covered with a sheet and cured, and the compressive strength is increased between 7 and 21 days after construction is completed.
Sprinkle water twice at a rate of 1.5 to 2 ρ/m2 (effect) On-site test construction was carried out in October 1985 on a ground owned by the applicant with no access to anyone outside the company, and its wintering conditions were evaluated in 1988. When inspected in mid-February, there was no frost heaving, the compressive strength was 31.4 kq/cm2, and the hydraulic conductivity was 6
10-' cm/sec, which was about the same number as on the 28th. Furthermore, the general clay court built at the same ground was completely frozen, and rainwater had weakened it to the point that it could not be used.

(Effects of the invention) As described above, the present invention provides the following advantages when constructing construction soil:
Soil in the range of SL to LS is mixed with a hydraulic material, and the soil water content is compacted to 1.
A construction soil construction method characterized by adding water so as to increase the volume by 2 to 1.5 times, stirring, and then rolling. After mixing and stirring, water is added so that the soil water content ratio becomes 1.2 to 1.5 times the optimal soil water content ratio for soil tamping, and then compacted within 7 to 21 days. By climbing the construction, characterized by water sprinkling on the pressure surface at least once,
Not only can the initial target compressive strength be obtained, but it also has the effect of being water permeable.

In addition, in the second invention, by spraying water at 1.5 to 2β/m2 at least once during 7 to 21 days after completion of construction, the compressive strength can be significantly increased without reducing water permeability. It also has a frost heaving prevention effect.

Therefore, in the conventional soil cement construction method, water permeability was never considered, but the construction soil construction method of the present invention not only has water permeability, but also compressive strength, and is ideal for construction with no frost heave. Since it can provide soil and is also economical and inexpensive like the soil cement method,
The method for constructing the construction soil of the present invention can be applied to various sports stadiums such as Sports Surf Ace, tennis clay courts, which are said to be the most difficult among them, sidewalks, jogging courses, etc.
Alternatively, if artificial turf is used for the lower subgrade of the main sports stadium, it is ideal because it has compressive strength, water permeability, good drainage, and does not freeze up even in sub-zero temperatures, and is suitable for conventional soil cement construction methods. It has special effects, such as being able to be applied to applications that could not be applied previously.

Claims (1)

[Claims] 1) When constructing the construction soil, the soil whose texture is in the range of SL to LS is mixed with a hydraulic material, and the soil water content ratio is adjusted to 1.0%, which is the optimum soil water content ratio for compacting the soil. A construction method for construction soil that requires water permeability, which comprises adding water so as to increase the volume by 2 to 1.5 times, stirring, and then compacting. 2) When constructing the construction soil, mix the soil with a soil texture in the range of SL to LS with a hydraulic material, and adjust the soil water content ratio to 1.2 to 1.5 times the optimal soil water content ratio for compacting the soil. A construction method for construction soil that requires water permeability, which comprises adding water to the soil, stirring it, and then applying water to the compacted surface at least once during 7 to 21 days after compaction. 3) The water added so as to be 1.2 to 1.5 times the water content of the soil during soil compaction requires the water permeability of claims 1 and 2, which contains a synthetic resin emulsion. Construction method of construction soil.