JPS61227954A - Manufacture of high property magma concrete - 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] This invention uses unused resources such as volcanic ash, volcanic sand, and volcanic rubble as raw materials for magma, and waste materials such as debris, and uses ordinary cement at room temperature. This relates to a method of manufacturing concrete for construction and civil engineering with high physical properties under pressure.0 [Conventional technology] In recent years, combined with the finiteness of resources and energy conservation issues, waste and unused materials are being produced. Utilizing resources and saving oil in the manufacturing process, such as room-temperature molding methods, and energy saving and resource saving of buildings through the insulation and durability of the resulting products have become important issues.
For this to be put into practical use, overall high physical properties such as strength are required. From this point of view, attempts have been made to make concrete using volcanic ash and volcanic rubble, but all of them simply substituted aggregates such as river sand or gravel and followed the same cross-contact method, so they were not profitable. Due to its physical properties, the concrete produced could not be used as a structural material, and only lightweight blocks were manufactured.

[Problem that the invention seeks to solve]

Conventionally, concrete made from volcanic ash or volcanic rubble lacks strength no matter how much cement is added.
Issues such as water permeability and carbonation have been limited to non-structural materials such as Class 5 lightweight concrete, but firstly, the compressive strength of the volcanic rubble itself is 35 to 35 s o kf/d. Second, the surface of volcanic rubble is rough and uneven, and during mixing, cement and water are absorbed into the air bubbles, reducing the effective bonding amount of cement by half, resulting in poor workability. Something was causing it.

[Means for solving problems]

In view of these circumstances, the present invention uses volcanic ash, which is a fine aggregate with a grain size of 0.6 wg or less, whose use in conventional concrete has been restricted, to create not only conventional volcanic ash concrete, but also river sand and river gravel concrete. 0 In other words, its composition is that first, volcanic ash or volcanic sand and Kira or similar fine particles are used as fine aggregates, and after they are wetted, The first feature is that cement particles are strongly attached (adhered) to the surface of the fine aggregate by adding cement and drying. That is, in the present invention, the raw materials are not simply kneaded at the same time, but are wetted with water beforehand and then powdered cement is added. Note that the above-mentioned "wet state" refers to a state in which when held normally with one hand, it becomes lumpy due to the adhesive force of water, and if it is already in that state, it can be used as a raw material as is. Also, [Kiraj] is a type of industrial waste that is generated when silica sand, which is a raw material for glass, is washed and selected. It is also called ``mizu pilot''. These are glassy fine particles that are approximately spherical, which is in contrast to reeds and volcanic ash, which have needle-like or irregularly complex shapes.

Next, admixtures such as ligurin sulfonic acid or other surfactants (trade name such as Hygelt) and water are added, but at this time, fine aggregate with strong cement adhesion is added. The surface becomes slippery. In addition, since cement works effectively only when it surrounds the surface of the aggregate, the amount is increased by 2 to 3 times, so the amount of cement used can be reduced. This results in the formation of a fine outer shell layer.

Fresh concrete with a slump value of, for example, O to 151 is made by adding the fine-grained adhesive (mortar) medium K and an inorganic foam such as volcanic rubble, which will be described later, as coarse aggregate. At this time, the fine aggregate adheres to the surface of the coarse aggregate and forms a large outer shell layer. Therefore, this concrete can be considered to have a double structure as its skeleton, consisting of an outer shell layer that surrounds fine aggregate, and an outer shell layer that is connected to the outer shell layer and surrounds coarse aggregate.

One of the characteristics of the volcanic rubble used as coarse aggregate here is that it also contains fine particles of waste (dust) generated during the sieving and selection process, and this is due to the particle size of 0.
．． Although it is about 0.01 to 5 fl, it is a part of hard and somewhat heavy volcanic rubble, which has a different origin from volcanic ash, and is a fine inorganic foam. This is mixed with large volcanic rubble of about 5 to 30 pieces and used as coarse aggregate.

Next, this fresh concrete is poured into a predetermined formwork. At that time, as mentioned above, even though the slump value is extremely low at 0 or 151 or less, when a slight vibration is applied, this fresh concrete exhibits amazing fluidity, filling every corner of the formwork. be done. This was compacted, cured at room temperature and hardened, and was able to develop a compressive strength of 200kg7at or more in the first week, which is usually considered the compressive strength of the fourth week.

[Action and effect]

Although the theoretical basis for such better-than-expected results has not yet been fully elucidated, it can be considered as an excellent translation. First of all, by adding Kira, ■ Kira is a fine glass sphere with a rounded appearance similar to volcanic ash with a complicated shape, and if you use this mortar that contains it, it will be possible to remove volcanic debris with extremely uneven surfaces. The surface of the formwork now has a stable spherical shape, and when vibration is applied to it, the coarse aggregate volcanic rubble collapses due to the action of the bearings, without having to increase the amount of water or cement as was done in the past. It fills every nook and cranny of the plastic and provides workability (plasticity).

■At the same time, these fine grains prevent the formation of junk, and the surface becomes sticky and dish-like, and the dirt blocks the capillaries and becomes dense, improving waterproofness. There are two points to mention. Secondly, if the wood and volcanic ash are wetted and then cement is added to the mixture and then air-wired, the fine cement particles will firmly adhere to the surface of the wood and volcanic ash, and the fine aggregate will be completely absorbed. becomes cement-like, meaning that the amount of cement has increased 2 to 3 times.

(2) When water mixed with an admixture such as a surfactant is added to this and kneaded, it is immediately dispersed and mixed well, producing a mortar with good workability. ■Since the surface of each mortar particle is viscous, it tends to adhere to the surface of the coarse aggregate, so the bubble openings are covered to prevent paste and water from entering. ■Therefore, the entire amount of cement used for this works effectively on adhesion of the aggregate.■The amount of water required for the crosstalk is greatly reduced, and the water/cement ratio is 5
Since it is possible to reduce the difference between 5 and 65 cm by 30% or less, the cement is dense, which increases early and final strength and improves waterproofness. ■Furthermore, when the cement is dense, it prevents the lightweight aggregate from floating and separating, eliminating strength problems. ■Also, since the air bubbles in the coarse aggregate are closed, it is possible to mix poorly, so there is no drying, shrinkage, cracking, etc., and it can now be used in basements, etc. (2) The moisture that was previously present in the fine aggregate in a wet state is gradually provided as moisture necessary for water utilization reactions during curing, producing an effect similar to that of underwater curing. etc. Thirdly, by using aggregates with various shapes and particle sizes in two steps, the resulting outer shell layer is a type of large eggshell-like body that itself is a fine small eggshell-like body. The result is a complex three-dimensional honeycomb structure that looks like it was formed and connected together. Moreover, due to the above-mentioned factors and probably the reaction product of water-soluble silicic acid in volcanic ash and Kira and free lime in cement, the material is difficult to form even though it is molded at room temperature and pressure. It is thought that it was extremely dense and had significantly increased strength and waterproofness.

As described above, according to the present invention, the strength of lightweight structural concrete, which was previously considered impossible, can be developed at an early stage by using magma raw materials such as industrial waste and unused resources such as volcanic ash as the main materials. Moreover, it is watertight and prevents water permeation, does not corrode the reinforcing steel, has improved acid resistance and heat insulation properties, has high physical properties, and is extremely economical.
[Example] Kira 3351 in a moist state, volcanic sand from Miyakejima in a moist state 211j with a grain size of 5 or less, and 350 kg of Portland cement), and a waterproof thickener (trade name Magco). ))
Put 28 kg into a mixer and mix for 15 seconds, then add a mixture of water 102j and admixture (trade name HIGELT N) 7j and knead for 3 to 4 minutes to form a fine and sticky mortar. can get.

Among them are volcanic debris from Miyakejima with a particle size of 5 or less, and 5 to 5
5541 mixed with 30 tIux was added and kneaded with a mixer to make fresh concrete in which the surface of the coarse aggregate was completely sticky and covered with mortar. This is 2,700 m deep, 4 m wide, 500 m long, and 9,000 m long.
, 150 mm thick, reinforced vertical formwork for basements and compacted using a vibrator, then left to cure in the air at room temperature, and the formwork was removed the next day to make it waterproof. Economically obtained high-strength basement.

In addition, the compressive strength according to the above example was 185ky/in 3 days.
at, 256kg/d in 7 days 450ky7a in 128 days
A value of t was obtained. However, the specific gravity is 1.85 (1), so if it is only volcanic ash, it is white. Increased by 1. The water absorption rate has been significantly improved to approximately 2%.

Claims (1)

[Claims] Moist volcanic ash or volcanic sand and wet Kira or similar fine particles are used as fine aggregate, cement is added to this, dry kneaded, and then a cement admixture and water are added to make mortar. To those with a particle size of 5 mm or less and those with a particle size of 5 to 30 m
A high-physical magma characterized by mixing volcanic rubble mixed with M as coarse aggregate, mixing it, pouring the resulting fresh concrete into a predetermined formwork, applying vibration, and compacting it. Concrete manufacturing method.