JPH0359025B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic formulation comprising a hydraulic material, such as a cement or gypsum formulation, with a reinforcing agent. Conventionally, hydraulic substances such as cement concrete, cement mortar, and plaster have been used in large quantities as materials for construction and civil engineering because they have excellent rigidity and compressive strength. However, on the other hand, these materials have poor bending strength, toughness, etc. Since it has the drawbacks of being inferior in quality and prone to cracks, it is actually put into practical use after reinforcement such as reinforcing bars and the addition of face materials. In order to improve these shortcomings of hydraulic materials, particularly their toughness and crack resistance, short fibers made of metal, glass, or synthetic resin have also been incorporated. However, since these have a simple shape, they tend to come off when tensile stress or shrinkage stress is applied, and the reinforcing effect is insufficient. In view of the above-mentioned current state of hydraulic materials, the inventors of the present invention have conducted intensive studies to develop hydraulic compounds with even improved toughness. The present invention was achieved by discovering that a hydraulic material blended with a nonwoven fabric laminated with fibers satisfies this purpose. The term "toughness" used in the present invention refers to the amount of work required to break when bending stress is applied to a material, and specifically, the area occupied by the deflection-load curve obtained in a bending test. That is, it is displayed as an absorbed energy value. The hydraulic substances of the present invention include hydraulic cements such as portland cement, white portland cement, alumina cement, silica cement, magnesia cement, blast furnace cement, and flyash cement, mixtures of these cements and silica sand, gypsum, lime, Examples include inorganic materials such as chalk, cement mortar, calcium carbonate, magnesium carbonate, aluminum hydroxide, and mixtures thereof. In addition, these hydraulic substances may include paraffin, wax, thermosetting water-soluble resin, various polymer emulsions, curing accelerators,
Hardening retarders, sand, aggregates, fly ash, etc.
There is no problem in blending reinforcing fillers such as vermiculite, perlite, wood chips, and wood wool. The reinforcing material used in the present invention is basically a small piece of a synthetic resin net-like material that has been stretched as necessary. Examples include nets that are extruded into threads and bonded diagonally and dots (product name: ``Netron''), synthetic resin nets used in fishing nets, etc., and nets that are cross-woven with high denier filaments. Of these, split fiber warp-warp laminated nonwoven fabrics are particularly preferred. As shown in Figure 1, this non-woven fabric is made by uniaxially stretching a synthetic resin film, making small cuts to expand the continuous split fibers to an appropriate width, and then stacking them on the warp and warp and fixing them. However, the actual product is "Warif" (product name,
manufactured by Nippon Petrochemical Co., Ltd.) and “Toughbell” (product name,
(manufactured by Kanebosha). The synthetic resins used for this nonwoven fabric include polyolefin resins such as polyethylene and polypropylene, nylon 6, and nylon 66.
Among these, resins having stretchability are particularly preferred. When this split fiber nonwoven fabric is used for the purpose of the present invention, the following advantages can be obtained. That is,
First, since the split fiber nonwoven fabric has been subjected to a stretching process on its warp and weft, it has high strength and significantly improves toughness. Second, as shown in Figure 1, this non-woven fabric has moderate openings through which the hydraulic substances join hands and create an anchoring effect, so hydraulic substances mixed with reinforcing materials This means that the reinforcing material will almost never slip through when bending stress or impact force is applied to it, and the strength of the material can be fully utilized. Thirdly, since the small pieces of split fiber nonwoven fabric have a two-dimensional structure, entanglement does not occur when blending with hydraulic substances that accompany conventional single fibers made of synthetic resin that have a one-dimensional structure. Uniform mixing is possible and workability is improved; for example, if the hydraulic substance is concrete, conventional concrete mixing equipment can be used as is. Fourth
Since the nonwoven fabric of the present invention can be used as it is by simply cutting a commercially available nonwoven fabric into small pieces, it is easy to obtain, and at the same time,
It is also possible to use the trimming loss of the edges that occurs during the split fiber nonwoven fabric manufacturing process, which is excellent in economical efficiency. The small pieces of the synthetic resin net-like material used in the present invention are generally produced by suitably cutting a wide and long net-like material. The shape to be cut may be square, rectangular, or circular, but the dimensions for square or circular shapes are 5 to 30 mm on one side or diameter; for rectangular shapes, the short side is 3 mm or more, and the long side is 5 to 30 mm.
It is preferably 50 mm or less. If the dimensions are outside the above range, the reinforcing effect may not be sufficiently expressed or uniform dispersion with the hydraulic substance may deteriorate. There is no particular limitation on the amount of the synthetic resin net material used, but it is generally preferably in the range of 0.5 to 5% by volume. If it is 0.5% by volume or more, no significant reinforcing effect can be obtained, and if it is more than 5% by volume, the viscosity of the compound increases significantly, making uniform dispersion difficult, and filling into molds may become impossible. The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to the Examples. In addition, the toughness value was measured by the following method.
In other words, for a 4 x 4 x 10 cm regular square prism test piece, with a span of 100 mm and a bending speed of 1 mm/min,
A point bending test is carried out, and the area occupied by a deflection of 3 mm on the obtained deflection-load curve is measured. As a reference, the area in the case where no reinforcing material was added (Comparative Example 1) was set as 1, and the area in the case where the reinforcing material was added was shown as a relative value. In addition, this test was conducted for 5 points each, and the average value is shown. Comparative Example 1 100 parts by weight of ordinary Portland cement was mixed with 200 parts by weight of sand passed through a 20-mesh sieve,
60 parts by weight of water was added to this and kneaded. This kneaded material was filled into a 4 x 4 x 16 cm aluminum formwork coated with polyethylene for corrosion protection.
It was allowed to stand for a while to solidify. After curing this coagulated material in water for 1 day and in air for 6 days, a bending test was performed, and the obtained results are shown in Table 1. Example 1 Split fiber nonwoven fabric made of polyethylene as a reinforcing material (product name: "Nisseki Warif HS24", manufactured by Nippon Petrochemicals Co., Ltd.)
was cut into 10 mm square pieces. As in Comparative Example 1, 100 parts by weight of ordinary Portland cement and 200 parts by weight of sand were added.
Pre-mix parts by weight, and add 1% by volume of the above reinforcing material to this.
(This volume % was calculated assuming the specific gravity of the blend to be 25 and the specific gravity of the reinforcing material to be 0.95) was added and thoroughly mixed, and then 60 parts by weight of water was further added and kneaded. After coagulating and curing this in the same manner as Comparative Example 1,
A bending test was conducted. The results obtained are shown in Table-1. Examples 2 to 4 Bending tests were conducted by blending, solidifying, and curing in exactly the same manner as in Example 1, except that the amount of reinforcing material used or the cut dimensions were changed as shown in Table 1.
The results obtained are shown in Table-1. Comparative Examples 2 and 3 Compounding, coagulation, and curing were carried out in exactly the same manner as in Example 1, except that 1% or 2% by volume of polypropylene split fibers (manufactured by Plasticizer Co., Ltd.) with a length of 3 mm were used as the reinforcing material. A bending test was conducted.
The results obtained are shown in Table-1. 【table】

[Brief explanation of drawings]

FIG. 1 shows a schematic diagram of an example of a warp-warp laminated nonwoven fabric of split fibers used in the present invention. 1: Longitudinal split fiber, 2: Latitude split fiber, 3: Opening.

Claims (1)

[Scope of Claims] 1. A hydraulic compound characterized in that a reinforcing material consisting of small pieces of a synthetic resin net-like material having rigidity in both directions is blended into a hydraulic material. 2. The hydraulic compound according to claim 1, wherein the hydraulic substance is cement and a compound thereof. 3. The hydraulic compound according to claim 1 or 2, wherein the reinforcing material is a warp-warp laminated nonwoven fabric of stretched split fibers. 4. The hydraulic compound according to any one of claims 1 to 3, wherein the amount of reinforcing material used is in the range of 0.5 to 5% by volume.