JPS63219704A - Execution of constructed soil having 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 method for constructing construction soil, the economical soil cement method is generally used.

This soil-cement method has a variety of applications, including roads with both rigidity and deflection, streets, lower and upper bases for airports, and surface treatment of slopes that are subject to periodic or continuous water inundation or wave action. , cores of earth dams, linings of reservoirs, etc.

The conventional soil cement construction method has not been applied to the above-mentioned sites, or it has been selected based on usage, and the amount of cement used is extremely high (this amount is used to tamp down the soil to achieve the optimum soil moisture content). Therefore, the construction soil obtained by the soil cement method is naturally non-permeable and non-permeable. Since it is applied to sites where water permeability is required, soil cement construction methods that are permeable have never been considered until now.

On the other hand, sports stadiums, sidewalks, jogging courses, etc., are facing problems due to softening of the ground surface due to rainwater, or restrictions on when and how long they can be used.

Also, recently, the lower base course of sports stadiums constructed using artificial grass or artificial grass filled with dry sand has been studied.

Therefore, the inventor of the present invention developed the above-mentioned sports surf ace,
For the subbase of artificial grass, sidewalks, jogging courses, etc.
I was able to make a small attempt to apply the soil cement method.

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

7. 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 characteristics of soil cement are that when trying to increase water permeability,
There is a contradictory relationship in that the compressive strength decreases, and if you try to increase the compressive strength, the water permeability decreases, so it is very difficult to solve the above drawbacks.

In addition, among the 17J stadiums, tennis clay courts are required to be water permeable and have sufficient compressive strength to provide appropriate bounce and cushioning, making it the most difficult sports surface. be.

The present inventor is an engineer in the field of civil engineering and sports facilities, and believes that in order to find use of soil cement in sports surf aces, etc., it is necessary to overcome the various drawbacks of soil cement as described above. I am well aware that this is an extremely difficult skill. However, the low cost of soil constructed with soil cement is a major attraction above all else, and the present inventors dared to take on the above-mentioned difficulties and have been conducting research for many years. Through research and experiments, we have now obtained new knowledge and 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.

The soil in this range has a quality of ``+'' that is easy to mix with hydraulic materials and easily increases compressive strength when compacted. In this process, called pretreatment, the soil and hydraulic material are mixed and coagulated, and the soil is poured into the soil in the range of SL to LS with adjusted particle size.

To explain an example of this case, the moisture content of 1 m3 of soil with soil texture of CL ~ 1 is set between 15% and 40%, and cement 3
If you mix it with 0 to 50 kq and leave it for a day and night, you can adjust the particle size to soil texture or around the SL to LS range.

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 compacting soil whose soil texture is in the range of SL to LS is approximately 6 to 15% on the LS side and approximately 15 to 25% on the SL side.
%.

Soil compaction Optimum soil water content ratio 1 m3 of soil with 17% soil moisture content is mixed with 100 kq of cement, soil water content ratio is 21.7%, which is 1.28 times the soil compaction optimal soil water content ratio. Adjusted by sprinkling with water and stirring (& When pressure is applied 4 to 5 times with a 4t roller, the water permeability coefficient is 4x)
The compressive strength was 17 kg/am2 at ○-' am/sec.

In addition, in order to adjust the soil water content ratio, it is sufficient to water only the trees, but it is sufficient to water the synthetic resin emulsion f1 m3 of soil at 10 to 20 g.
The important thing in this regard is that when hydraulic materials and soil are compacted at the optimal soil water content ratio, the compressive strength is not high, but there is water permeability. Compacting the soil If the soil is compacted below the optimum soil moisture content, the water permeability will either be good or the compressive strength will drop significantly.

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, in order to increase the bending strength of the soil surface and prevent soil surface destruction due to cold weather, it is recommended to water the soil at a rate of 1 to 2 β/m2 while curing the sheet for 1 to 5 days after completion of compaction. The bending strength of the surface was 28 days old and the areas without watering were 2 and 7.
kq/cm2, whereas 3,4 kq/cm2
was able to be significantly enhanced.

In addition, if water is sprinkled within 1 to 5 days after completion of construction, the soil 1 and cement may not be strongly solidified, so 0.05 to 0.
Sprinkling a 0.3% aqueous solution does not generate muddy water, so the effect is more pronounced.Next, we will explain how to prevent frost heaving.In general, if the compressive strength is 20kc+/cm2 or more, the soil will have a frost heaving inhibiting effect. It is said that

To increase this strength, it is necessary to apply 1.5 to 2β/m to the pressure surface at least once during 7 to 21 days after completion of compaction.
Water permeability does not change, but the compressive strength is 28゜a' kq/am2 after 28 days.
can be significantly increased.

Therefore, we were able to create soil that is permeable, does not freeze up, and does not cause destruction of the soil surface due to cold weather.

Next, we will explain how to construct the lower subgrade for tennis clay courts and artificial grass sports stadiums on-site. First, it is decided whether to build up the floor or excavate the floor at the site. Both the bevel and the excavation are carried out approximately 30 cm deep. 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, bring good quality soil in the range of SL to LS to the site, or if used on site, check to see if it contains soil particles of 1057/ or less or 5% or more. If the soil is wet, adjust the particle size with cement.

The above soil is compacted with crushed stones, etc., and then leveled in approximately 30 cm rows, and a cement percentage of 100 kq/m3 is sprinkled on the soil, and the soil and cement are mixed using a tractor or the like. The soil water content ratio of this mixed soil was investigated, and water was added to 1 m3 of soil along with 15 parts of ethylene acid emulsion and 9 parts ( Sprinkle water and stir the soil again with a tractor, etc. After this, step 4 is temporarily rolled 2 to 3 times with a roller, then correct the unevenness, and then complete with zero rolling. Once completed. In order to increase the bending strength of the soil surface, a sheet was placed on top of the soil for 1 to 5 days and while it was curing, a 0.04% aqueous solution of polyethylene oxide was sprayed at least once at 1 to 2β/m2, and 7 days after the completion of construction. 1-2 to increase compressive strength during ~21 days.
Watering is carried out at a rate of 1.5-2β/m 2 times.

(Function) Test construction was carried out on the applicant's grounds in October 1985, with no outsiders allowed to enter.The test construction was carried out in October 1985, and its wintering conditions were investigated in mid-February 1988, and there was no frost heaving and no compaction was observed. Strength is 28.3kq/cm2, bending strength is 3
, 7 kg/am2, hydraulic conductivity is 4xlO-' cm
/sec and the 28th day of production are the same (the numerical values are shown below).

In addition, 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.
The soil with a soil quality ranging from SL to LS is mixed with a hydraulic material, and the soil moisture content is compacted to 1.5%, which is the optimum soil moisture content.
Add water so that the volume is 2 to 1.5 times, stir, and roll, then apply 1 to 2β/
Water permeability ゛i! which is characterized by m2 water sprinkling. : Since this is a construction method for construction soil, by adding wood that is 1.2 to 1.5 times the optimum moisture content of the soil, the initial target compressive strength can be obtained and the process is completed. 1 more to go
Since the soil is subjected to 1 to 2 β/m2 failure on the compacted surface at least once during 5 days, the soil surface has bending strength and water permeability.

In addition, 1.
By sprinkling water at 5 to 2 β/m 2 , the compressive strength can be significantly increased without reducing water permeability, and the frost heaving prevention effect can also be achieved.

Therefore, although water permeability was never considered in conventional soil cement construction methods, the construction soil construction method of the present invention not only has water permeability, but also has compressive strength and bending strength, and is ideal in that it does not have frost heave. The construction soil of the present invention can be used as a construction soil for various sports stadiums, and is the most difficult method among them. If used for the lower subgrade of tennis clay courts, sidewalks, jogging courses, or artificial turf sports stadiums, it has compressive strength but is permeable and has good drainage, even in sub-zero temperatures. It is ideal because it does not have frost heave, and it has bending strength and does not cause surface damage due to cold weather, so it can be applied to applications that could not be applied with conventional soil cement construction methods, and has special effects.

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. Water permeability is determined by adding water so as to increase the volume by 2 to 1.5 times, stirring, rolling, and then sprinkling water at 1 to 2 l/m^2 on the rolling surface at least once during 1 to 5 days. Construction method of construction soil. 2) Soil tamping The method for constructing constructed soil with water permeability according to claim 1, wherein the water added so as to be 1.2 to 1.5 times the optimum soil moisture content contains a synthetic resin emulsion. . 3) The method for constructing constructed soil with water permeability according to claim 1, wherein the water sprinkled on the compacted surface for 1 to 5 days after compaction contains a polymer soil aggregating agent. .