JPS63217015A - Method and plant for continuously mixing soil with soil improving agent - Google Patents

Abstract

PURPOSE:To permit large amounts of soil to be mixed continuously by a method in which soil and a soil improving agent are spread alternately in layers on a belt conveyer and they are mixed together on the joint part of the conveyers for mixing reclaiming soil. CONSTITUTION:A belt conveyer 3 is continuously operated, soil in a hopper 1 is supplied to soil feeders 2 and 2', and soil improving agent in a soil improving agent storage tank 4 is supplied to a feeder 22. Whereupon, soil and soil improving agent are alternately loaded in layers on the belt of the conveyer 3 and mixed by damper chutes 6 and 10 in the joint part of belt conveyers 3 and 21. Large amounts of soil can thus be continuously mixed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously mixing earth and sand and soil conditioner and a plant for carrying out this method.

The materials used for reclamation and embankment are the main materials that make up the reclaimed soil and embankment, so their properties affect the difficulty of construction and the quality of the reclaimed soil and embankment after completion. It is desirable to select and use materials.

However, selecting and using high-quality materials is not so easy economically.

In order to eliminate this drawback, reclaimed soil and embankments are created by mixing soil conditioners in advance with collected soil and sand. Various types of mixers are used to manufacture reclaimed soil and embankment made of this mixed material.For example, drum-type continuous mixers are used for improved structural soil such as road bases, but these mixers differ in their capacity and size. ,price,
It is not suitable for continuous mixing of large volumes of soil in terms of labor saving and automation.

The underlying problem of the present invention is to create reclaimed soil and embankments that enable accurate, large-volume, and continuous mixing of soil and soil improvement materials, and that minimize the generation of dust during this process. method and to build a plant for carrying out this method.

This problem lies in the method according to the present invention, in which soil is first spread on a continuously moving belt conveyor for the purpose of creating reclaimed soil or embankment, and then a soil conditioner is spread on the layer of soil. Repeat this process several times or more times, and finally sprinkle soil on these alternating layers, and then insert a soil conditioner into the middle of the thus formed soil layers in the form of a sand inch. The solution is to mix at the transfer section of the conveyor.

Furthermore, in another configuration of the present invention, when the mixed material is used for underwater reclamation, a liquid soil conditioner such as a separation preventive agent is further sprayed onto the material formed in the above-mentioned mixing section. added.

Further, in the present invention, the parameters or blending amounts of the soil conditioner and soil in the mixing step are controlled by an automatic control mechanism connected to a measuring device or a metering device for these.

Moreover, in the present invention, the above-mentioned problem is solved in the following manner in a plant for carrying out the above-mentioned method.

That is, the above-mentioned plant includes a soil improvement material supply section consisting of one or more supply conduits for supplying the soil improvement material from a storage tank, a metering device, and a soil improvement material feeder device disposed between the soil and sand feeder devices; a hopper; Alternatively, a stock pile, multiple earth and sand feeders arranged along the flow of the belt conveyor to continuously feed earth and sand onto the belt conveyor, a belt conveyor that transports earth and sand, and a water content meter that continuously measures the water content ratio of earth and sand. A material mixing section consisting of a ratio measuring device and a conveyance measuring device that continuously measures the total amount of soil and soil improvement material supplied onto the belt conveyor; and a final belt conveyor, one or more intermediate A damper chute that mixes the alternating soil layers formed by the material mixing section at each transfer section of the belt conveyor and guides the mixture to the next belt conveyor; .

Furthermore, in the present invention, in order to further process the mixed material formed in the above-mentioned mixing section when the mixed material is used for underwater reclamation, a liquid soil improving material storage section, this liquid soil improving material is provided. The second mixing system consists of a device that pumps the material, a device that continuously sprays the liquid soil conditioner, and a damper chute that spreads the mixture of soil and powder soil conditioner in a strip at the discharge section of the belt conveyor. It has a department.

With the above method and plant, it is now possible to prepare reclaimed soil or embankment, which has been done roughly in the past, by sufficiently mixing the ideal mixture, and this preparation of reclaimed soil or embankment has become possible. is carried out in a continuous mode of operation, and the advantage is achieved that large quantities of soil can be produced in a very economical process.

In addition, there are two ways to improve the mixing condition: using multiple feeders for soil and soil conditioner to create a sand inch with five or more layers, and installing damper chutes at multiple locations to repeatedly mix. However, it is desirable to select a combination that takes into consideration the properties of the earth and sand and soil improvement materials, the transportation capacity of the plant, and restrictions on the installation location.

The invention will now be described in detail with reference to the embodiments illustrated in the accompanying drawings.

FIG. 1 shows the simplest case of the plant according to the present invention, that is, two earth and sand feeders and a damper chute.
The case of locations is schematically illustrated.

First, as a work process order, the earth and sand stored in the hopper or stock pile l separated from the belt conveyor 3 by the partition wall 20 is transferred to the first water content ratio measuring device 1.
1, the soil is fed onto the belt conveyor 3 by the soil feeder 2 while the water content ratio is constantly measured so as to be stacked on the belt surface.

On the other hand, the soil improvement material is prepared in powder form and stored in a storage device 4, from which it is metered via a conduit 5 by a metering device 12 that continuously measures the amount of the soil improvement material supplied. It is supplied to the improvement material feeder 22 so that it is layered to a substantially uniform thickness on top of the previously supplied soil layer. Here, two material layers are formed on the belt conveyor 3, consisting of a soil layer and a soil improvement material layer.

Next, while the soil stored in the hopper or stock pile 1 is measured by the second water content measuring device 11', the soil layer already formed on the belt conveyor 3 is measured by the soil feeder W2°. It is supplied to be similarly laminated on the improving material layer.

Here, on the belt conveyor 3, there are three layers: an earth and sand layer immediately above the belt conveyor, a soil improvement material layer on the surface of this earth and sand layer, and an earth and sand layer again on top of this soil improvement material layer. A material soil layer, that is, a soil layer, a soil improvement material layer, and a soil layer is formed.

This three-layer material layer is then transferred to belt conveyor 3.
The soil is transported further, and the transported amount of soil and soil improvement material is continuously measured by a transported amount measuring device along the way. This layered compact leaves the belt conveyor 3 at its terminal end, but at this time it hits a damper chute 6 provided at the front in the flow direction, and the layered compact is divided by this damper chute 6. The three layers are shuffled and mixed. That is, the first mixing of the above-mentioned materials is performed at this position.

This shear mixing effect is achieved by the special construction of the damper chute described below.

FIG. 2 shows a first embodiment of this damper chute 6, and FIG. 3 shows its front view. As is clear from FIG. 2, this damper chute 6 consists of a front plate 30 that is perpendicular to the center line of the belt conveyor, and the material of this plate 30 is in the direction in which it abuts and flows down. Two baffle plates 31 that are approximately right-angled triangular in cross section are provided approximately at the center.

Earth and Sand Layer - Soil Conditioning Material The layered body consisting of one earth and sand layer collides with this baffle plate 31 and is divided and destroyed.

Guide side walls 32 inclined toward the center are provided on both sides of the lower end in the flow direction of the plate body 30, and these guide side walls 32 are provided with folded portions having widths toward the center at the edges. Exit 33 of plate body 30 divided by this guide side wall 32
is tapered. The flowing material layer takes on a spiral behavior by rubbing against the baffle plate 31 of this plate body 30 and then against this guide side wall 32 while colliding with them.
At this time, this soil layer compact is completely broken apart and mixed.

FIG. 4 shows a second embodiment of the damper chute 6, and a fifth embodiment of the damper chute 6.
The figure shows its front view. As is clear from these figures, the damper chute 6 according to this embodiment has a bottom that intersects at a shallow angle with a parabola drawn by a layer formed body consisting of a layer of soil and a layer of soil conditioner discharged from the belt conveyor 3. bar 34 and inclined side guide plate 35
It is formed from. This side guide plate 35 is tapered downward, ie in the direction of material flow. The material for the three-layer soil layer formed body, which is layered in the order of soil layer - soil conditioner layer and soil layer and is conveyed by the belt conveyor 3, is discharged from this belt conveyor, and as it falls, it hits the above-mentioned bar 34. When the bar 34 intersects with the bar 34 and slides down on both sides of each bar 34, each layer is broken apart and mixed.

The materials sheared and mixed by the damper chute 6 are transferred by a belt conveyor 21 and either directly supplied to a work site or stored.

Here, when using the mixed material formed in the above-mentioned mixing part C for underwater reclamation such as ocean reclamation,
This mixed material is further transported by the belt conveyor 21 and is thrown into the damper chute 10 provided in front of the discharge port of the belt conveyor 21. As shown in FIGS. 6 and 7, this damper chute 10 has a plane perpendicular to the center line of the belt conveyor 21, and has vertical guide plates 36 rising from the plane on both sides of the lower part. Here, the material discharged from the conveyor 21 and collided with the damper chute 10 spreads along the plane of the damper chute, forming a thin, uniformly thick curtain-like layer with the inner width of the vertical guide plates on both sides of the lower part of the damper chute. At that time, a liquid soil conditioner such as a separation preventive agent is sent from the liquid soil conditioner storage section 7 via the pressure feeding device 8 in a plane direction perpendicular to the flow of this vertically falling curtain of earth and sand. However, several spray devices (nozzle mechanisms) 39 (sixth
(see Figure and Figure 7).

This mixed earth and sand material is then loaded as finished material onto an earth carrier or other suitable conveying means.

The parameters or blending amounts of the soil conditioner and soil treated in the mixing method and mixing plant according to the present invention are set based on the dry weight of the soil. This blending amount setting standard value is input to the automatic control mechanism 15, and the following measuring devices and weighing devices are connected to this, namely, a water content ratio measuring device 11.11" that continuously measures the water content ratio of earth and sand. , a device 12.12゛ that continuously measures the supply amount of powdered soil conditioner, and a device 13 that continuously measures the amount of soil and soil conditioner on the belt conveyor. Operation and operation control is performed.This control style will be explained based on the control block diagram shown in FIG.

In A, reference values are set for the hourly transportation amount and shipping unit amount of earth and sand (in a natural state), the natural moisture content of earth and sand, and the mixing ratio of soil improving materials.

Actual values according to the course of plant operation are detected in B, and the detected actual values are given to C, where the difference between this actual value and a reference value is compared and calculated by a comparison element and a calculation element, and this comparison - The difference value signal formed by the calculation is fed back to each measuring device and weighing device of the plant at D, and these measuring devices and weighing devices are controlled. In this case, the set reference value, the detected value, the calculated value, and the operating parameters based on these values are recorded in the recording section of E.

This control mechanism has not been described in detail since it is constructed in a known manner and is not a feature of the invention.

As an example of the above control, the blending amounts of earth and sand and soil conditioner will be specifically explained below.

48 parts by weight of the earth and sand supplied from the upstream earth and sand feeder 2, 4 parts by weight of the soil improvement material supplied from the storage section 4,
The earth and sand supplied from the earth and sand feeder device 2 on the downstream side are
Three layers of mixed materials are formed as eight stacked parts. In some cases, a fluid soil conditioner may be added to this mixed material from the reservoir 7.
It is added at a ratio of 0.01 parts by weight.

In this case, the water content ratio of the earth and sand loaded onto the belt conveyor 3 is measured by a water content ratio measuring device 11. The dry weight of the soil can be determined by The blending ratio of the soil conditioner is given to the automatic control mechanism 15 as a reference value, and the soil feeder device 2 is instructed to mix the soil conditioner in the set amount with respect to the dry weight of the soil supplied to the belt conveyor 3. , are continuously measured by a powder flow meter 13. At this time, the supply amount of earth and sand and soil improvement material is measured by the above-mentioned measuring device, inputted to the control mechanism 15 as an electric signal, compared and calculated, and fed back to each measuring device and weighing device, and the supply amount is controlled to the set target value. be done.

EXAMPLE The following experiments were carried out to demonstrate the effects obtained by the mixing method and plant for this purpose according to the invention.

The experimental equipment had a belt width of 35 mm and a belt speed of 100 m/min.
Three belt conveyors are arranged in series, and earth and sand hoppers with feeders No. 1, No. 2 are installed from the upstream side of the belt conveyor on top of belt conveyor No. 1, which is the most upstream part of the work.
was installed. A soil conditioner hopper with a feeder was installed between the two sand hoppers.

Of the three belt conveyors, NO, 1% No, 2”'
A damper chute for mixing is installed on the conveyor, and
A flat damper chute is attached to the discharge section of the 3-belt conveyor, and below it two spray nozzles are installed on each side of the mixed material of soil and soil conditioner, which flows down in the form of a belt from the flat damper chute. The device was designed to spray liquid soil conditioner from the soil.

Continuously feed earth and sand equivalent to 30 kg in dry weight from the No. 1 earth and sand hopper onto the No. 1 belt conveyor, and at the same time, continuously form a layer of 2°4 kg of soil conditioner on the earth and sand layer. supply so as to be provided. From the No. 2 earth and sand hopper, earth and sand equivalent to a dry type ff of 130 kg is continuously supplied onto the layer of earth and sand and soil quality improvement material to cover the soil quality improvement material.

The mixed material supplied, transferred and discharged by this device was deposited in a box.

The soil used in the experiment was sandy soil, the soil conditioner was ordinary Portland cement, and the liquid soil conditioner was an anti-segregation agent dissolved in salt water.

The mixing ratio of each material is 4% (wt%) of ordinary Portland cement and 1 part of anti-segregation agent to 311 kg of dry earth and sand mold.
00 mg.

Regarding the degree of mixing, Uke visually observed the mixed material deposited in the box, measured the calcium content, and measured the chloride ion concentration.

With a normal damper chute that is not designed for mixing, uneven distribution of the soil conditioner is clearly visible on the surface and cross section of the mixed material deposited in the box, and there is no mixing effect.

In the case where a mixing damper chute was used, uneven distribution of the soil conditioner was not observed visually, and samples were collected from many points on the deposited material and the following tests were conducted.

The calcium content contained in ordinary Portland cement, a soil conditioner, in each sample was measured and converted to the content of the soil conditioner. For the anti-separation agent in the liquid soil conditioner, the concentration of chlorine ions in the dissolved salt water was measured and converted to the content of the anti-separation agent.

Measurement result 1: Mixing ratio of soil conditioner (ordinary Portland cement) supplied: 4.0% Content in sample: average 3.8χ (standard deviation 0°194)
, variation coefficient 0.1) 2. Liquid soil conditioner (separation prevention agent) Supply mixing ratio 100a+g/Kg Content in sample Average 91mg/Kg (Standard deviation 34
．． 2. Coefficient of variation 0.37) From the above results, the plant according to the present invention allows continuous mixing of soil improvement materials.

This method also prevents fine powder soil conditioners from scattering during transportation, thereby preventing dust.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a mixing plant for soil and soil conditioner according to the present invention, Fig. 2 is a sectional view of a first embodiment of a damper chute used according to the present invention, and Fig. 3 is a front view of Fig. 2. Figure 4 is a sectional view of a second embodiment of the damper chute used in accordance with the present invention, Figure 5 is a front view of Figure 4, and Figure 6 is a damper chute used for mixing a fluid soil conditioner. FIG. 7 is a front view of FIG. 6, and FIG. 8 is a block diagram of a control device for carrying out the method according to the invention. The symbols in the diagram are: 1...Hopper or stock pile 2.2゛...
・Soil feeder device 3...Belt conveyor 4...Soil quality improvement material storage device 5...Soil quality improvement material supply conduit 6...Damper chute 7...Liquid soil quality improvement material storage device 8...Liquid soil quality Improvement material pressure feeding device 9... Spraying device 10... Damper chute 11.11'', soil water content ratio measuring device 13... Transport amount measuring device 14... Liquid soil improvement material measuring device 15... Control Mechanism 22... Soil improvement material feeder Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure m7 Figure 8 Procedural amendment April 20, 1988

Claims (1)

[Claims] 1. In a method for continuously mixing earth and sand and soil improvement materials, the earth and sand are first spread on a belt conveyor that moves continuously for the purpose of creating reclaimed soil or embankment, and then the soil quality improvement material is mixed. Spreading the improving material on the above soil and sand layer is repeated once or multiple times, and finally, soil is spread on these alternating layers, and the soil improving material is sandwiched between the soil and sand layers thus formed. It is characterized by the fact that the alternating layers of material soil are mixed at the transfer section of the belt conveyor while being transferred.
A method of continuously mixing soil and soil improvement materials. 2. A method of continuously mixing earth and sand and soil conditioner, characterized in that when the mixed material is used for underwater reclamation, a liquid soil conditioner is further added to the mixed material by spraying. , a method of continuously mixing soil and soil conditioners. 3. According to claim 1 or 2, the parameters of the soil conditioner and soil or their mutual blending amounts are controlled by an automatic control mechanism that is connected to a measuring device or a measuring device for these. the method of. 4. In a plant for carrying out a method for continuously mixing earth and sand and soil improvement materials, one or more supply conduits (5...) for supplying soil improvement materials from the storage tank (4). , Weighing device (12・
) and the earth and sand feeder devices (2, 2'...); Soil conditioner supply section (A) consisting of soil conditioner feeder devices (22, . . . ); Hopper or stock pile (1 ), multiple earth and sand feeders (2, 2'...) arranged along the flow of the belt conveyor (3) in order to continuously feed earth and sand onto the belt conveyor (3), transporting earth and sand. Belt conveyor (3)
, a water content ratio measuring device (1) that continuously measures the water content ratio of soil and sand.
1, 11'...) and a conveyance measuring device (13) that continuously measures the total amount of soil and soil improvement material supplied onto the belt conveyor; At each transition section of the belt conveyor (21) and one or more intermediate belt conveyors (3...), the alternating soil layers formed by the material blending section (B) are mixed and transferred to the next belt. Damper chute (6,...
); a first mixing section (C) consisting of; a plant for continuously mixing earth and sand and a soil improvement material; 5. In a plant for implementing a method for continuously mixing earth and sand and a soil improvement material, the mixing section (C) is a liquid soil improvement material storage section (7), and a device for pumping this liquid soil improvement material. (8), Equipment for continuously spraying liquid soil conditioner (9)
and a damper chute (10) that spreads a mixture of earth and sand and powder soil conditioner in a belt shape at the discharge section of the belt conveyor.