JPH0321683B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an asphalt mixture relay device that is installed between an asphalt plant and an asphalt construction site, and is capable of quickly supplying high-quality asphalt mixture to the asphalt construction site. .

As is well known, asphalt mixture is made by adding asphalt as a caking agent to heat-dried aggregate at a predetermined mixing ratio and kneading it, and it is widely used as a paving material for roads and other purposes. be done.

It is also desirable that the asphalt plant be installed near the asphalt construction site.

However, asphalt plants not only require a large amount of land, but also generate vibrations, noise, dust, etc., so it is virtually difficult to install them in or near urban areas. The current situation is that it takes a long time to transport the Alfa Alto composite material, and the quality of the Alfa Alto composite material has deteriorated.

In recent years, mixed material silos have been installed in urban areas to store asphalt mixture produced in asphalt plants in a heated state. It is also possible to store it in wood silos. However, when the asphalt mixture is stored in the above-mentioned mixture silo, the asphalt deteriorates over time, and the asphalt mixture clogs the outlet due to the adhesive force of the asphalt.

In order to prevent asphalt from deteriorating, the inside of a mixed material silo has traditionally been filled with an inert gas such as carbon dioxide. However, even if filled with inert gas, the airtightness of the mixture silo may be low, or the inert gas concentration may decrease because the lid of the outlet is opened when taking out the asphalt mixture little by little. Therefore, a sufficient deterioration prevention effect cannot be expected.

The present invention has been proposed in view of the above, and includes a lumber silo equipped with a heating device that stores in a heated state a poorly mixed asphalt mixture with an asphalt mixing ratio lower than a predetermined value, and a poor mix asphalt mixture discharged from the mixed material silo. It has a weighing device that measures the mixed material, a weighing device for melted asphalt, and a kneading device, and the mixed material silo transports the poorly blended asphalt mix manufactured at the asphalt plant and stores it in a heated state. Then, the poorly blended asphalt mixture stored in the mixture silo is discharged from the mixture silo and a certain amount measured by a weighing device is supplied to the kneading device, and the dissolved asphalt is weighed by the weighing device and fed to the kneading device. The asphalt mixture is supplied, and the kneading device stirs and mixes the measured poorly blended asphalt mixture with the weighed dissolved asphalt, increasing the mixing ratio of asphalt to aggregate to a predetermined value before shipping. This relay device for asphalt mixture is capable of quickly supplying high-quality asphalt mixture to the asphalt construction site even if the asphalt construction site is far away from the asphalt plant.

An embodiment of the present invention will be described below based on the drawings.

In order to manufacture asphalt mixture, as shown in the drawing, aggregate transported from an aggregate stockyard 1 in an asphalt plant by a belt conveyor 2, etc. is led to a dryer 3, and inside the dryer 3, the temperature is 150 to 170°C. Heat and dry at high temperature. Then, the heated and dried aggregate is transferred to a sieving device 5 by a lift 4, and is sieved by particle size.
...Stored by particle size.

Asphalt composite materials have different blending ratios of aggregate and asphalt depending on the intended use. Therefore,
If necessary, filler is mixed with the heat-dried aggregate, and at a predetermined mixing ratio (generally 5 to 6
% by weight) of dissolved asphalt is mixed and kneaded to produce an asphalt mixture. However, in the present invention, a poorly mixed asphalt mixture with a low mixing ratio of asphalt is produced in an asphalt plant, and this poorly mixed asphalt mixture is transported to a relay device.

For example, in the case of an asphalt mixture used as a base layer for road paving, 20% by weight of No. 5 aggregate, 38% by weight of No. 6 aggregate, 15% by weight of No. 7 aggregate, and 12 Coarse sand of 12% by weight, fine sand of 12% by weight, and filler of 3% by weight are measured by a weighing machine 7 and charged into a kneading machine 8. When the mixture of each aggregate and filler is 100, asphalt dissolved at 140 to 160°C is supplied from the asphalt weighing machine 9 to the kneading machine 8 at a ratio of 1.0 to 2.5% by weight and mixed (hereinafter referred to as primary mixing). ) and sufficiently kneaded using a kneader 8. When using this asphalt composite material,
2.5-4.0% by weight of asphalt is missing.

In addition, to make a fine-grain asphalt mixture used for the surface layer as a road paving material, 25% by weight of No. 6 aggregate, 20% by weight of No. 7 aggregate, and 24% by weight of coarse sand, 25% by weight of fine sand and 6% by weight of filler are measured by a weighing machine 7 and fed to a kneading machine 8. And if the mixture of each aggregate and filler is 100,
1 to 3% by weight of dissolved asphalt is added from the asphalt measuring machine 9 and kneaded, but this asphalt mixture lacks 3.0 to 5.0% by weight of asphalt.

In this way, the poor mix asphalt mixture with a reduced mixing ratio of dissolved asphalt to aggregate is discharged from the mixer 8, and this poor mix asphalt mix is installed in a dump truck or the like at a location far away from the asphalt plant. It is transported to a certain relay device of the present invention.

This relay device includes a lift 10 for lifting the poor mix asphalt mixture being transported, a mix silo 11 for storing the poor mix asphalt mix lifted by the lift 10, and the mix silo 11 Since the heating device 12 is provided, the poorly blended asphalt mixture can be maintained at an appropriate temperature, for example, 140 to 170°C, and heated and kept warm. Therefore, the asphalt component in the poorly blended asphalt mixture is not cooled and hardened. In addition, the poorly blended asphalt mixture has a small amount of asphalt component and has weak adhesive strength, so even if it is stored for a long time, it will not clog near the outlet 11' formed at the lower end of the mixture silo 11.
Because it has an appropriate cohesive force, aggregates of different sizes will separate, and larger aggregates will not remain and smaller aggregates will not descend first. Therefore, even if the poor mix asphalt mixture is stored in the mix silo for a long period of time, the condition of the aggregate in the poor mix asphalt mix does not change.

The relay device of the present invention includes not only the mixture silo 11 equipped with a heating device for heating and storing the poorly blended asphalt mixture as described above, but also the mixture silo 11.
a weighing device 15 that measures the poorly blended asphalt mixture discharged from the meter; a weighing device 14 that measures and discharges the dissolved asphalt; A kneading device 14 that supplies a certain amount of dissolved asphalt measured in step 14 and mixes it with stirring.
and has.

When shipping the asphalt mixture from the relay device, the outlet 1 at the lower end of the mixture silo 11 is
A measuring device 15 measures the poorly blended asphalt mixture discharged from 1' and supplies a certain amount to the kneading machine 13, and a measuring device 14 measures the dissolved asphalt and supplies a certain amount to the kneading machine 13 for kneading. Machine 13
Then, the above-mentioned poorly blended asphalt mixture and dissolved asphalt are sufficiently stirred and mixed (hereinafter referred to as secondary mixing), the asphalt mixing ratio is increased to a predetermined value, and the well-kneaded state is discharged and loaded onto a dump truck, etc. Transport it to the asphalt construction site.

For example, in the case of an asphalt mixture used for the base layer of road paving materials, the predetermined value, that is, the final asphalt mixing ratio is about 5% by weight. Therefore, when 1.0 to 2.5% by weight of dissolved asphalt is mixed in the primary mixing, 2.5 to 4.0% by weight of dissolved asphalt is added from the asphalt weighing machine 14 in the secondary mixing in the relay device and mixed in the kneading device 13. It is thoroughly kneaded and shipped together with poorly blended asphalt mixture.

In addition, in the case of asphalt mixture used for the surface layer of road paving materials, the final asphalt mixing ratio is approximately 6% by weight, so the primary mixing ratio is 1.0 to 3.0%.
If % by weight of asphalt is mixed, in the secondary mixing, 3.0 to 5.0 % by weight of dissolved asphalt is supplied from the asphalt measuring machine 14 to the kneading device 13, added to the poorly blended asphalt mixture, and thoroughly kneaded.

The asphalt mixture containing a predetermined amount of sufficiently kneaded asphalt is transported to an asphalt construction site by a dump truck 16 or the like and laid by a finisher or the like.

When asphalt is mixed with aggregate, the following phenomena occur.

(1) If the amount of asphalt is 1.0% by weight or less in the primary mixing, the aggregates of the poorly mixed asphalt mixture stored in the mixture silo may separate depending on their size, or the poorly mixed asphalt mixture may be transferred to the mixture silo. A phenomenon in which dust is mixed occurs when it is added. Additionally, if the amount of asphalt in the primary mixing is 3.0% by weight or more, the deterioration of the asphalt contained in the poorly blended asphalt mixture will increase,
In extreme cases, the quality of the asphalt mixture may deteriorate or the outlet of the mixture silo may become clogged.

(2) The deterioration of asphalt is quite large when viewed from the primary mixing alone, but when measured together with the secondary mixing, it is much smaller than the deterioration of asphalt mixtures caused by conventional storage methods.

Therefore, as is clear from the above results,
The asphalt mixing ratio of the primary mixture is 1 to 3% by weight.
is the most appropriate.

Note that the final asphalt mixing ratio and blending ratio are not limited to those described above, and can be changed as appropriate depending on the application.

As explained above, according to the present invention, it is possible to provide high-quality asphalt mixture from the mixture silo of a relay device installed in a place remote from an asphalt plant, such as in a city area.

In other words, since the asphalt mixture with a poor blend is produced at the asphalt plant, not only does it generate almost no dust, but even if the mixture is stored in a heated state for a long time in a silo, the asphalt mixture will remain stable. When taking out the aggregate from the silo, the mixing ratio of aggregate will not change, and the poorly mixed asphalt mix will not clog the outlet of the mix silo. Furthermore, even if the asphalt deteriorates in the mixture silo, the amount of degraded asphalt is very small, and the quality of the final asphalt mixture is improved by adding and kneading fresh dissolved asphalt before shipping. It will not deteriorate. Therefore, even if the asphalt mixture is shipped from a mixture silo separated from the asphalt plant, it is possible to ensure the same quality as conventional asphalt mixture shipped directly from the asphalt plant, and it is possible to ensure high quality asphalt mixture. material can be shipped.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention. 11 is a mixture silo, 12 is a heating device, 13 is a kneading device, 14 is a weighing machine, and 15 is a measuring device.

Claims (1)

[Claims] 1 A lumber silo with a heating device that stores in a heated state a poor mix asphalt mixture made by mixing heat-dried aggregate of 91% by weight or more, asphalt of 3% by weight or less, and filler of 6% by weight or less. , a measuring machine for the poor mix asphalt discharged from the mixed material silo, and a kneading device, and the poor mix asphalt mixture produced in the asphalt plant is transported to the mixed material silo and kept in a heated state. The poorly blended asphalt mixture stored in the mixture silo is discharged from the mixture silo and a certain amount measured by a weighing device is supplied to the kneading device, and the melted asphalt is calculated by the weighing device and then transferred to the kneading device. A kneading device mixes the calculated poor mix asphalt mixture with the weighed dissolved asphalt, increasing the mixing ratio of asphalt to aggregate to a predetermined value before shipping. Relay equipment for asphalt composite material.