JPS5930851B2 - grouting method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a grouting method, and more specifically, a long-term (28 days) grouting method.
This invention relates to a grouting method that can suppress the initial water heat generation without impairing the strength of the grout, thereby preventing the occurrence of cracks that are dependent on shrinkage caused by temperature changes.

Conventionally, a cement admixture for grout made of calcium sulfoaluminate-based substances and various chemicals added thereto is known from Japanese Patent No. 799240.
r! /? Grouting mortar made by mixing about 5 to 30 parts of the above cement has excellent performance in terms of non-shrinkage and breathing, so it is used for fixing anchor bolts on bridges, for example, and installing machine pedestals. There is.

However, as bridges and machinery become larger, the amount of grout used there also inevitably increases, so the temperature at the center of the redundantly grouted mortar can reach up to 100°C, and as it descends, it heats up. Cracks often occur as a result of stress remaining inside.

The simplest solution to this problem is to use moderate heat cement, reduce the amount of cement, or use a special method to cool the construction. However, in the latter method, this type of grout is used for fixing with anchor bolts, etc., and is injected into the pores of ICs. Since there are many uses for this, it requires a great deal of equipment and labor to perform construction while cooling, or is often impossible.

The present invention belongs to the former technique, and proposes a grouting method that suppresses the initial water heat generation and does not impair the development of long-term strength. 2300ct/? u
A part of the above cement is used by replacing it with cement particles having a particle size of 88 μm to 5 μm.

This will be explained in detail below. Normally, when cement particles are coarsened,
Since the water utilization reaction is delayed, as a result, the initial water utilization heat generation is suppressed and the temperature rise can be suppressed, but in this case, a major problem associated with this is that the strength decreases.

However, we have discovered that this drawback can be overcome by replacing a portion of this cement with cement particles having a particle size of 88 .mu.m to 5 .mu.m.

If cement particles used here are finer than 88μ, there is no difference from conventional cement, and if the cement particles are coarser than 5μ, even if initial heat generation due to water use can be suppressed, long-term strength decline cannot be prevented. Preferably, 88 to 149μ is 20 to 60%, and 149μ is
~250μ is 10~50, 250~590μ is 10~
The cement has a particle size structure of 10% Iu and 590 μm to 5 μm, and the remainder is 88 μm or less.

Cement clinker is used to obtain such cement particles.
There is no need to newly manufacture cement by pulverizing it or granulating it, and it is possible to use so-called re-milled cement, which is often produced when manufacturing ordinary cement.

The amount of cement particles used to replace conventional cement is 1
0 to 60% is preferred.

The reason for this is that if the amount is less than 10 inches, the effect of suppressing the initial water heat generation will be small, and if the amount is more than 60 inches, the long-term strength will decrease, and in either case, the intended purpose will not be achieved.

The method of the present invention applies to all grouts using cement as a hardening agent.
In other words, it can be applied to cement water glass grout, cement asphalt grout, iron powder-based cement grout), calcium sulfoaluminate-based cement grout, etc.

The present invention will be explained below with reference to Examples, and all parts and parts described in the specification of the present invention are expressed on a weight basis.

Example 1 Specific surface area 3000ct/? A cement admixture for cement admixture for calcium sulfoaluminate grout is added to ordinary Portland cement with the grain size distribution shown in Table 1 in various proportions, and the product name ``Denka Tuscon'' (Denka Kagaku Kogyo Co., Ltd.) is used as a cement admixture for calcium sulfoaluminate grout. 100 parts of grouting cement prepared by internal grinding with 16% of the product (manufactured by Mikuni), particle size 5-0.
For a mortar mixed with 200 parts of 15rft7rL acid and 50 parts of water, the temperature at the center of the mortar and the physical properties of the mortar 12 hours after the cross-crossing were measured.

The results are shown in Table 2.

Incidentally, instead of the mill-returned cement having the particle size shown in Table 1, mill-return cement with a particle size of 5 to 6 Inm was used to make Jiboku 5.
When I conducted an experiment with the same content, experiment A8 yielded almost the same results.

Example 2 Instead of ``1 Denka Tuscon'' in Example 1, a grouting cement containing 50% of the trade name ``MBECO'' (Nisso Master Builders Co., Ltd. M), which is an iron powder-based cement admixture for grout, was used by internal grinding. Table 3 shows the results of similar measurements.

Claims (1)

[Claims] 1. A grouting method characterized in that cement particles having a grain size of 88 μm to 5 μm are used to replace 10 to 60 μm of cement.