JPH0242781B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field of the Invention) The present invention relates to a method of manufacturing building materials such as blocks, or constructing road bases, backfilling of structures, building frames, etc., mainly using inorganic powder. More specifically, the crushed material, which is a primary hardened material made by adding a small amount of binder to inorganic powder, etc., is spread on formwork, road bases, backfills of structures, construction frameworks, etc., and the crushed material is crushed and compacted by compaction. As a result, strength is generated through the subsequent secondary curing, thereby manufacturing or constructing reinforced building materials such as blocks, road bases, building frames, etc. (Conventional technology) Conventionally, stone powder generated during the production of crushed sand, waste fine sand generated during silica sand refining, reducing group slag powder generated from electric furnaces, and cement hydrate generated from wastewater treatment at ready-mixed concrete factories have been used. The main sludge (hereinafter referred to as ready-mixed concrete drainage sludge), gypsum and fly ash generated from flue gas treatment at coal-fired power plants are generated in huge amounts, but there is little effective reuse and they are disposed of. There are many things that are. Although some of them are currently being reused, if their occurrence increases in the future, there will be a limit to their reuse and they will eventually have to be disposed of, but this disposal will become increasingly difficult in terms of environmental conservation. It is inevitable. Furthermore, from the standpoint of effective resource utilization, there is a strong desire to develop techniques for reusing these wastes. On the other hand, the current state of reuse technology for construction work, which can utilize large amounts of these inorganic powder wastes, is that it is too difficult to directly add a binder and pour it into the site as a fluid and solidify it. also requires a lot of bonding material. In addition, when compacting a mixture using a compaction machine using a large amount of these inorganic powders, the larger the proportion of powder, the less the supporting force of the mixture during compaction, making it difficult to obtain sufficient compaction density. Nakatsuta. For this reason, it is necessary to try to make it into granular solids using cement etc., to solidify it into lumps and then crush it, or to sinter it as granules at high temperature.
Attempts have been made to sinter it into blocks at high temperatures and then crush them to form high-strength granular solids that can be used as substitutes for crushed stone and the like. However, this method requires a large amount of binder such as cement to obtain high strength, and consumes a large amount of thermal energy for sintering, so it is considerably more expensive than using crushed stone. Since it is only used for low value-added applications, there has been a desire for a simple and economical recycling technology. (Problems to be Solved by the Invention) As described above, the conventional technology aims at replacing crushed stone, etc. Therefore, recycled materials are manufactured as granules, and the strength of the material that makes up the granules is also low. It was necessary to approximate that of crushed stone. For this reason, whether solidified using a binding material or solidified by sintering, rocks are manufactured with the aim of achieving a compressive strength of several hundred kg/cm ³ to several hundred kgf/cm ^2. . Therefore, either a large amount of binder is required or it is necessary to sinter at a high temperature (for example, about 1,000 degrees Celsius). Furthermore, the shape of the recycled product has been determined by either granulating it before consolidation and sintering, or crushing it after consolidation and sintering, since it is necessary to granulate it. (Means for Solving the Problem) On the other hand, the method of the present invention involves applying a hydraulic binder to inorganic powder or acting on the inorganic powder itself to gradually reduce the hydraulic property (for example, hydration). (It may take several days to several months or more for the action to be almost complete)
After adding the materials that exhibit the desired properties and mixing and molding, the primary cured material, which is in the stage where the hydration reaction of the mixture continues and the hardening strength is still increasing, is once crushed, and the crushed material is compacted into a predetermined shape. Or, by leveling and compacting the crushed material on the ground such as a roadbed or embankment, the crushed material is homogeneously integrated by compacting it into a crushed and compacted state until the granules of the crushed material do not retain their shape at all.
As secondary hardening progresses due to residual hydraulic properties,
It can be molded into strong cured products and used to construct roadbeds and construction frameworks. Moreover, by doing this, it is easy to mold the cured product, and the strength after secondary curing of the roadbed and construction framework is only about several tens of kgf/ ^cm2 (for example, asphalt pavement by the Japan Road Association). According to the guidelines, 30 kg for cement stabilized roadbed.
f/cm ² or more, and 20Kgf/cm ² or more with lime stabilization treatment. ) Therefore, the amount of binding material can be reduced compared to the production of roadbed materials by conventional methods, or firing at high temperatures is not necessary. The inorganic powders mentioned here include rock powder (waste from crushing factories, etc.), fly ash (waste from thermal power plants), raw concrete drainage sludge made of cement hydrate, silica sand waste (silica sand for glass, frog's eye clay) water sieve waste in refining such as), mold waste sand,
There are mineral slag, etc. Binding materials that have binding strength themselves include ordinary Portland cement, blast furnace cement, fly ash cement, silica cement, etc., and materials that harden by bonding with inorganic powder include blast furnace slag powder. and lime (slaked lime/quicklime), blast furnace slag powder and ready-mixed concrete drainage sludge, fly ash and ready-mixed concrete drainage sludge, etc. Methods for molding the primary cured product include casting (pouring), pressurization, extrusion, and the like. In addition, aggregate such as sand, crushed stone, gravel, crushed slag, etc. can be mixed in the mixing step during the production of the primary cured product or in the crushed material of the primary cured product. Furthermore, when mixing, chemical admixtures for cement concrete may be added to accelerate or delay setting, and alkaline substances or calcium chloride may be added to the crushed material to promote secondary hardening. It is also effective to use, for example, a mixture prepared for the purpose of producing a primary cured product in the method of the present invention. (Example) The method of the present invention will be explained in more detail by giving examples. By the way, the technology of the present invention is not limited to the conditions of the embodiments shown below. 90 parts by weight of fly ash, which is waste from thermal power plants shown in Table 1, as an inorganic powder, and 10 parts by dry weight of the ready-mixed concrete drainage sludge shown in Table 2 as a binding material, and a water-containing cake or paste. The water content in the mixture was adjusted to 35% of the total solid content of the fly ash and fresh concrete drainage sludge, mixed in a kneader, and extruded into 10 cm in diameter by an extrusion molding machine. , molded into a cylindrical shape with a length of about 20 cm, and then left to cure and primary harden. After that, the compressive strength of the primary cured product was approximately 10 kg as shown in Table 3.
When it reaches around f/cm ² (usually after several days),
The primary hardened material is crushed with a crusher to a maximum particle size of 20 mm or less, then crushed, and the crushed material is spread on the road pavement subbase (preferably the finished thickness is 15 cm or less). Using compaction machines for road paving work, such as macadam rollers, pneumatic tire rollers, vibrating rollers, etc., the granules of the crushed material of the primary hardened material are crushed by compaction and integrated into a sufficient density by compaction. . (If a larger construction thickness is required, this can be achieved by repeating the above operations.) Then, this integrated compacted body will again develop strength due to hardening due to the remaining hydraulic properties. The strength increases again due to the second hardening, and in this example, the compressive strength of the compacted crushed material of the first hardened material reached 42Kgf/ ^cm2 at 10 days of age as shown in Table 3. fully satisfies the standards. Of course, the limit of this strength is selected depending on the purpose, and its strength is adjusted by the blending, kneading method, primary and secondary curing periods, etc. For example, a compressive strength of 10 Kgf/cm ² after secondary hardening is sufficient for use as a backfill material or construction material after excavation for underground construction. Furthermore, molded products used as building materials can easily have a compressive strength of several hundred kgf/cm ² depending on the purpose.

【table】

【table】

[Table] Method (Effects of the Invention) As described above, the method of the present invention provides a method for producing a cured powder product, and has a remarkable effect on the reuse of inorganic powder waste, which is generated in large quantities. , The reuse of waste has great effects in terms of environmental conservation and effective use of resources. In addition, technically speaking, unlike filling with granular materials, secondary hardening is performed after consolidation and integration, so that under-consolidation, which is a drawback of granular materials, does not occur due to subsequent loads, vibrations, etc. As a result, the pavement above the buried area will not be adversely affected by the uneven bed. Unlike granular materials, it does not have large voids, so it does not reduce the bearing capacity due to water penetration, and has the advantage of having a significantly low permeability coefficient and high freezing resistance. When used as a backing material for structures or as a building frame material, it has characteristics that are significantly superior to general granular materials or soil. The specific gravity of the secondary cured material is small, and it is more effective in preventing roadbed freezing than ordinary granular materials.

Claims (1)

[Scope of Claims] 1. Inorganic powder and a hydrating binder are mixed and molded with appropriate moisture, and by curing, the compressive strength of the molded product increases from several Kgf/cm ² to several tens of Kg during the hardening process.
f/cm ² (hereinafter referred to as primary cured product)
The material crushed to an appropriate size (hereinafter referred to as crushed material) is spread on a formwork or on the ground, and the primary hardened material is crushed and compacted using a compaction machine to integrate it, and then further cured. and cured by the hydration action of the remaining unhydrated substance (hereinafter referred to as a secondary cured product), the cured product is characterized by having a compressive strength of several tens of Kgf/cm ² or more. Production method. 2 At the manufacturing stage of the primary cured product, gravel, sand,
The manufacturing method according to claim 1, wherein aggregate such as slag is mixed. 3. The manufacturing method according to claim 1, wherein aggregate such as gravel, sand, slag, etc. is mixed into the primary hardened material during or after crushing.