JP2001279653A - Curing method of earth treated with hardener and curing device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a curing method capable of easily performing curing while compacting treated earth after adding a hardener, that is, consolidation curing including removal of oozing-out water from the treated earth and a curing device for enabling this curing method. SOLUTION: This earth curing device treated with a hardener is characterized by being composed of a load applying device for allying a load from an upper part with the lengthwise direction set as the vertical direction to the treated earth filled in a cylindrical form having at least one end sealed by a porous plate for substantially passing only water and a drain device for draining water oozing out through the porous plate from the load-applied treated earth to the outside of a system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curing apparatus which enables curing of soil which is chemically stabilized using a solidifying material or the like under consolidation conditions, and an apparatus for measuring the effect of solidification treatment using the apparatus. It relates to a curing method for obtaining a test. In more detail, experiments were conducted on the consolidation, including the escape of water from the treated soil, which often occurs when embankment or backfilling with soft soil with column improvement, underground wall, and soil with added solidification material. The present invention relates to the provision of a curing device for simulating reproduction in a room, and a curing method for using the device to prepare a test specimen for measuring the effect of solidification treatment using a solidifying material. In the present specification, the soil after the addition of the solidifying material and in which the solidification is not sufficiently advanced is referred to as treated soil. After the solidifying material is added, the soil is cured, and the solidification / stabilization according to the ability of the solidified material is performed. The treated soil in the state where the stabilizing effect has appeared is referred to as a stabilized treated soil, and is roughly distinguished.

[0002]

2. Description of the Related Art As one of methods for stabilizing soft ground or soil, a chemical stabilization method in which a solidifying material such as cement or lime is added is known. In this method,
Normally, after mixing the sample soil collected from the ground to be improved in advance with various additions of the solidifying material in a soil test room,
The stabilized soil obtained by curing for a predetermined period is used as a specimen, the unconfined compressive strength is determined by a unconfined compression test, and the amount of the solidified material is determined in consideration of the improved target strength and the mixing performance of the construction machine. ing. In this uniaxial compression test, generally, the treated soil, that is, the soil to be treated added with the solidifying material is filled into a cylindrical form having a diameter of 5 cm and a height of 10 cm, compacted by a rammer or tapping, and the top surface is covered with a film. The uniaxial compressive strength of a specimen obtained by curing for a predetermined period in a stationary state is measured. That is, the uniaxial compressive strength of a specimen prepared under the condition that no external force other than its own weight is applied and drainage does not occur from any surface is measured.

However, in the columnar improvement of soft ground, the underground continuous wall, and the embankment or backfilling with the treated soil, the so-called fresh treated soil immediately after the addition of the solidifying material is compressed by the action of its own weight or the overload. Undergoing densification or consolidation. Due to this consolidation, and further, due to the accompanying decrease in water content, the degree of deformation or strength characteristics after solidification should have changed significantly from the state without consolidation. It is believed that more realistic and more practical measurements can be obtained by performing the test on the specimens that have undergone and that have exuded water during compaction.

[0004] There are already methods for performing a consolidation test on the soil itself. For example, the consolidation method is standardized by a consolidation test of soil itself and a triaxial compression test (CU, CD). However, each of these aims to measure the consolidation characteristics (compression characteristics) of soil and the shear strength after consolidation under isotropic stress conditions, so it is necessary to use a special formwork for the preparation of specimens. In addition, due to the complicated structure of the apparatus itself, it was inevitable that the number of specimens that can be manufactured and tested at the same time was limited. On the other hand, in order to grasp the stabilization treatment conditions using the solidified material, it is necessary to perform tests on a large number of test specimens prepared by changing the conditions. However, it is not suitable in terms of surface, and further improvement is required in terms of the size of the specimen and the like, which affects the accuracy of the measured values.
It has also been desired to develop a device that gives a test specimen taking into account the effect of water escape that occurs during compaction.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus which solve the above-mentioned problems of the conventional apparatus and method in the evaluation of a stabilized soil with a solidified material. That is, curing while adding consolidation to the treated soil after the addition of the solidifying material, that is, consolidation curing, can be performed easily including removal of seepage water from the treated soil, and the development of a curing device that enables it. Aim.

[0006]

Means for Solving the Problems The inventor of the present invention has been able to use a cylindrical form which has been conventionally used in a laboratory blending test for preparing a stabilized treated soil specimen. The present inventors have found that a device capable of performing the above-described method can be obtained by adopting a structure capable of removing seepage water during consolidation from the treated soil filled into the soil, and completed the present invention. That is, the present invention adds a solidifying material to the soil to be treated and cures the adjusted treated soil by adding a solidifying material to the treated soil for the purpose of obtaining a specimen for measuring the effect of the solidification treatment. After filling in a cylindrical form so as to be substantially sealed with a perforated plate that only allows water to pass through, a load was applied from the top by setting the longitudinal direction up and down, and a load was applied. The present invention relates to a method for curing a soil treated with a solidified material, characterized by discharging exuded water from the perforated plate derived from the treated soil out of the system by a drainage device. Further, the present invention is a curing device for adding a solidifying material to the soil to be treated and adding curing to the treated soil adjusted by mixing for the purpose of obtaining a specimen for measuring the solidification treatment effect, wherein at least one end is substantially at least one end. A load-loading device that applies a load to the treated soil filled in a cylindrical form sealed with a perforated plate that allows only water to pass through from the top with the longitudinal direction up and down. And a drainage device for discharging the exuded water from the perforated plate to the outside of the system. Hereinafter, the present invention will be described in detail.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The main part of the curing device of the present invention is a mold, a perforated plate (upper and / or lower), and a drain pipe (upper and / or lower) installed according to the position of the perforated plate. And a load device for the form part. FIG. 1 shows an example of the curing device of the present invention. The inner diameter or height of the specimen forming mold 2 is not particularly limited, but the ratio of inner diameter / height is generally 1/2. In particular, the method of preparing a specimen having the same inner diameter / height ratio, which does not compact the stabilized soil, based on the soil engineering standard
JSF T 8211990 ”, a cylindrical form (diameter 5 cm × height 10 cm or diameter 7.5 cm × length 15) used in an indoor compounding test of a solidified material-treated soil.
cm) is the most preferable method in terms of measurement accuracy, availability, and cost.

[0008] The first step of consolidation curing using the apparatus of the present invention is to fill the form with treated soil. Filling is performed by pouring a freshly treated soil that has not yet been solidified immediately after the predetermined amount of the solidifying material has been added and mixed into the soil to be processed into the formwork 2 having a bottom plate at the bottom, and then tapping or the like. The compaction is performed by an appropriate method to remove the voids. Although the treated soil is compressed in the subsequent consolidation process and the top surface naturally changes, the soil properties of the original soil and the specimen are adjusted so that the specimen height obtained after consolidation and curing is close to the formwork height. It is preferable to adjust the filling amount of the treated soil in consideration of, for example, the loading pressure on the soil. In this case, the treated soil volume to be filled is, of course,
Since the volume is larger than the mold capacity, the collar 3 is installed on the upper part of the mold to secure the filling capacity before compaction.

After filling the freshly treated soil, the bottom plate is removed from the bottom of the form, and the filter paper is placed on a lower porous plate 4b having the same diameter as the inside diameter of the form, which is installed at a predetermined position where pressure is applied on the consolidation device. Alternatively, the mold is placed such that the lower surface of the treated soil is positioned opposite to the filter cloth, and the pressing member 7 is inserted from above the mold to complete the mounting of the mold to the compaction device. When subjected to consolidation, the position dependence of the amount of seepage water from the treated soil filled in the formwork varies depending on the soil properties of the soil to be treated, and the installation of the perforated plate may be sufficient for only the upper or lower part depending on the treated soil. There are cases, but generally, perforated plates are installed on both upper and lower sides,
It is convenient to remove water from both the upper and lower surfaces. Naturally, drainage equipment will be installed up and down so that it can handle any case. The upper and lower perforated plates are installed in order to discharge water oozing out of the treated soil during the consolidation curing to the outside of the formwork. The upper perforated plate is in contact with the pressing member, and reduces the load from the pressing member on the treated soil. Will also have the function of communicating to the

The porous plate is not limited to a particular type as long as it can withstand an applied load, and porous stone, porous metal, and even a plastic porous plate known to have sufficient strength can be used. In this case, if a perforated plate having a mesh size substantially allowing only water to pass through is used, it is possible to remove only exuded water from the treated soil to the outside of the system using only the perforated plate. When using a coarse perforated plate, it will be used in combination with filter paper or filter cloth to prevent the escape of solid components.However, considering the necessity of washing the perforated plate after use, It is practically preferable to use a coarse perforated plate in combination with a filter paper or filter cloth, particularly a disposable filter paper. A filter medium is also a type of perforated plate, and in the present invention, the latter case, that is, a case where a perforated plate is combined with a filter medium, is also defined as "use of a perforated plate".

[0011] In the curing device of the present invention, water oozing out of the treated soil through the perforated plate at the time of consolidation is discharged out of the system via drainage grooves and drain pipes installed in contact with the lower surface or upper and lower surfaces of the treated soil. It has a structure that can be removed. For example,
In the apparatus shown in FIG. 1, the lower perforated plate 4b is placed just above the water intake of the lower drain pipe 8b installed through the curing device bottom plate.
Is installed, and the upper perforated plate 4a passes through a drain groove provided in a vertical direction substantially at the center of the pressing member 7 provided in contact with the upper porous plate 4a, and a groove provided in a horizontal direction inside the loading table so as to be continuous therewith. The structure is such that water can be drained from the drain pipe 8a to the outside of the system. The drainage ditch and the drainage pipe are not limited to the setting method shown in FIG. 1 as long as the exudate can be removed from the system, and are not limited to those shown in FIG. In addition, the drain pipe 8a,
If a valve is provided for each of the members 8b, it can be compacted and cured under non-draining conditions, if necessary, by closing it during compaction.

[0012] The curing device of the present invention is equipped with equipment for applying a load to the treated soil in the formwork. Any type of pressurizing equipment can be used as long as it can variably pressurize the treated soil in the cylindrical form. The method using the weight shown in FIG. 1 is the most preferable method for pressurization in terms of equipment cost. In this apparatus, the load of the weight 6 is transmitted to the processing soil 1 in the mold via the loading table 5 and the pressing member 7. The loading platform and the pressing member need not be integral. The load to be applied depends on the improvement purpose such as columnar improvement, embankment or backfill, etc.
Determined in consideration of factors such as depth (height) and groundwater level.
This value is up to 2.0 kgf / cm ² , that is, if the form diameter is 5 cm, it is sufficient if a load of up to 40 kgf can be applied.

In a device using a weight as a load means, the set value is determined by the total mass of the weight and the loading table. The weight is also 0.5, 1, 2, 4, 5, 10, 15 , 2
If you prepare 9 kinds of 0 and 30 kg, this [loading platform +
87.5 kg] can be covered in 0.5 kg increments, which is very convenient in terms of workability.

Further, by mounting the displacement gauge 9, it is possible to measure the volume change of the treated soil in the formwork as a height change over time. As the displacement meter, a dial gauge or an electric displacement meter can be used, but the electric displacement meter is very useful when automatic recording of volume change during consolidation curing is required.

After the consolidation organism reaches a predetermined age, it is immediately removed from the mold, and if necessary, the upper end surface of the specimen is smoothed, and a uniaxial and triaxial compression test is performed to measure the deformation and strength characteristics. The stabilization effect of the solidified material is evaluated. The consolidation curing can be performed in an arbitrary time unit. However, the degree of consolidation per unit time is largely attenuated as the solidification of the stabilizer (solidified material) progresses. After the convergence, the cargo may be unloaded.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to specific examples. Here, an example in which cohesive soil having a water content of 48% is used as the soil to be treated is shown. 60 kg of cement-based solidifying material for general soft soil (Eustabira 10) was added per 1 m ^{3 of} viscous soil, and kneaded with a 5 liter mixer for 5 minutes to obtain a freshly treated soil. This freshly treated soil was filled in a steel cylindrical formwork having a diameter of 5 cm and a height of 10 cm provided on a bottom plate and compacted by a tapping method.

The consolidation curing was performed using the apparatus shown in FIG. After moving the mold filled with the treated soil together with the bottom plate to the curing device so as to be located immediately above the bottom porous plate (porous stone) previously set at a predetermined position on the curing device base plate, the bottom plate is removed. Then, place the lower surface of the treated soil on the bottom perforated plate with the filter paper in between, and then install the perforated plate on the upper surface of the processed soil in the mold with the filter paper in between. Insertion completed the setting to the curing device.

The consolidation curing was performed by changing the applied load (mass) to 0 (no load), 10, 20, and 30 kg. Regarding the degree of progress of consolidation, the change in height of the surface of the treated soil was measured with a displacement meter. It was continuously measured and monitored. In addition, the whole apparatus is installed in a 20 ° C. constant temperature room. Table 1 shows the degree of consolidation 100 minutes after the start of consolidation at which consolidation can be considered to have converged for any of the loads. In Table 1, the height of the treated soil surface 100 minutes after consolidation is shown as the amount of settlement defined by the difference from the height of the treated soil surface immediately after filling.

Next, the effect of consolidation in the stabilization treatment with the solidified material was examined for the consolidation cured for 7 days of material age. 0 (no load), 10 kg, 20 kg, and 30 kg were prepared for each of the three types of loads, three uniaxial compressive strengths were measured, and the average value of the three samples for each load was measured at each load. As shown in Table 1.

[0020]

[Table 1]

When consolidation is applied to the treated soil which has not been sufficiently solidified in a state where drainage is possible, shrinkage of the specimen is added to the physicochemical action of the solidified material. The squat ratio is expected to be positively correlated with the loading load, and the uniaxial compressive strength after stabilization, for example, at 7 days of age, is expected to increase significantly. The results show that the curing device of the present invention provides a specimen that reproduces these two characteristics.

Next, the load on the specimen was fixed at 30 kg, and the test was repeated with different dates of preparation of the specimen, and the reproducibility of the strength improvement by the consolidation treatment was examined. Table 2 shows the results. The expression intensity has been very well reproduced. In order for a device or method designed to achieve a certain purpose to be practical,
When operated under the same conditions, it is indispensable that what can be regarded as the same and what gives the result are shown. The results in Table 2 show that the curing device of the present invention shows Is given.

[0023]

[Table 2]

[0024]

The curing device according to the present invention provides a stabilized soil specimen including effects of load and drainage. The reproducibility of stabilizing treatment effect expression in the specimen is also good. In addition, the mechanism is simple, and workability and economy are excellent. By using a specimen prepared using the curing device of the present invention,
Data including the influence of consolidation can be obtained, and using this data makes it possible to grasp stabilization processing conditions that are more realistic.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a curing device of the present invention.

[Description of Signs] 1 Treated soil 2 Formwork 3 Collar 4a Upper perforated plate, 4b Lower perforated plate 5 Loading platform 6 Weight 7 Pressing member 8a Upper drainage pipe 8b Lower drainage pipe 9 Displacement meter

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hidetoshi Fujino 1-6 off the coast of Kogushi-ji, Ube-shi, Ube-shi, Yamaguchi F-term in the Ube center of Ube Mitsubishi Cement Research Institute Co., Ltd. 2D040 AA01 AB03 AB07 CA01 CA03 GA00 2D043 AA01 AB00 BA10

Claims (4)

[Claims] (1) In order to obtain a specimen for measuring the effect of solidification treatment,
When the solidified material is added to the soil to be treated, and the cured treated soil is cured by mixing, at least one of the upper and lower portions of the treated soil is sealed with a perforated plate that substantially allows only water to pass through. After filling in the cylindrical form, the longitudinal direction is installed up and down and a load is applied from above, and the seepage water from the perforated plate derived from the treated soil to which the load has been applied is drained by a drainage system. A method for curing a solidified material-treated soil, wherein the method is performed by discharging to the outside. 2. In order to obtain a specimen for measuring the effect of solidification treatment,
A curing device for adding a solidifying material to the treatment target soil and curing the treated soil prepared by mixing and mixing, wherein at least one end is filled in a cylindrical form sealed with a perforated plate substantially allowing only water to pass therethrough. A load application device that applies a load from above with the longitudinal direction being the vertical direction with respect to the treated soil, and a drainage device that discharges seepage water from the perforated plate derived from the applied treated soil to the outside of the system. A solidified material treated soil curing device characterized by comprising: 3. The apparatus for curing a soil treated with a solidified material according to claim 2, wherein the cylindrical form for filling the treated soil is a cylindrical form for an indoor compounding test of the soil treated with a solidified material. . 4. A load-loading device is constituted by a transmission section which is inserted into the upper portion of the loading platform and the formwork and transmits a load to the treated soil in the form in conjunction with the lowering of the loading platform, and is installed on the loading platform. The solidified material treated soil curing apparatus according to claim 2, wherein the amount of load applied to the treated soil in the formwork is adjustable by a weight amount.