JPH02310006A - Kneading method of low-strength mortar - Google Patents

Abstract

PURPOSE:To supply a necessary quantity of low-strength mortar by kneading the same efficiently by omitting intricacy at the time of kneading without necessitating a plant for the kneading in a working site, by a method wherein an additive for lowering of mortar strength is agitated and kneaded uniformly with crude mortar within a drum of a mixermobile. CONSTITUTION:Unit cement in crude mortar is measured little than that of a case of an ordinary mortar by aiming at lowering of strength of the mortar and after sufficient kneading of the cement along with a fixed quantity of water and sand they are shifted to a drum of a mixerboile. Bentnite is loaded as an additive into the drum of the mixermobile arrives at a working site. A quantity of the additive is established in accordance with results of enforcement of serveral tests, the drum is turned at a high speed after loading of the established quantity of the same and agitation with the crude mortar is performed. With this agitation, homogeneity of the mortar is secured and sufficiently kneaded low-strength motar is generated hereupon.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a low-strength mortar kneading method that is easy to cut and remove after being cast into the ground.

[Conventional technology] Prevention of loosening of the ground caused by pulling out and removing existing piles from the ground, prevention of ground collapse during excavation due to cavities in the ground, and prevention of ground collapse after removing obstacles in the ground being excavated by a shield machine. For adjustment, etc., low-strength mortar is installed in the relevant part of the ground using IJ, which can be easily cut and removed later.

As this low-strength rutar, poorly mixed mortar, foamed or foamed rutar, etc. are used.

[Problem to be Solved by the Invention 1] The above-mentioned low-strength mortar is manufactured by kneading mortar and additives such as benthite or earth mortar and a foaming agent in an iMv plant installed on-site. , it will be driven into the ground as it is, and it will be destroyed. 1. In the case of cross-contact lines at the site, planning l-i; u will be complicated in arranging equipment, labor, materials, etc., and temporary, ;Q, , j, - It is also useful for installing plant equipment in narrow spaces. The i11 limit was 4-4, and the kneading efficiency was poor at a maximum of 6 to 10 m3/H culm.

This invention was devised in order to solve the conventional problems mentioned in item 1, and its purpose is to eliminate the need for equipment for kneading at work sites, and to eliminate the need for complicated kneading equipment. It is an object of the present invention to provide a method for kneading low-strength mortar, which can efficiently knead and supply the required amount of low-strength mortar without the need for additional steps.

[Means for Solving the Problems] -J 1'') The f+ feature of this invention is that the raw mortar mixed and kneaded in the factory is transported to the work site using a millimeter width, and the mortar is poured. Before installation, additives for low-strength mortar are added into the drum of the Miki 1 no-wheel, and the rotation of the drum uniformly stirs the mortar and additives to mix them into the low-strength mortar. There is a particular thing.

The amount of cement per unit in the above-mentioned raw mortar is set to be smaller than that of normal mortar in order to reduce the strength of the mortar, and after thoroughly kneading a predetermined amount of water and sand, be transferred.

During transportation by vehicle, raw mortar in the drum may undergo material separation and sand may settle, but it is later kneaded with additives (because of this, the material content during transportation is 1111'1).
．． ! 4.1 There are no particular problems when kneading low-strength mortar.

The pen 1~)-i1~ is put into the drum \\ in the Mikili that has arrived at the work site as an additive. The amount of this additive material is set according to the results of several test streams 21, and after the set amount is added, the drum is rotated at high speed and stirred with the raw mortar.

This stirring ensures the homogeneity of the mortar, resulting in a well-kneaded, low-strength mortar.

Such low-strength mortar can be cast into an excavated hole in the ground using a Remy tube, and after hardening, it quickly develops the same strength as conventional low-strength Iff mortar. Furthermore, it is hard enough to be cut and removed using a regular excavator or shield excavator.

[Example] (1) Mixing example raw mortar (Kg/7rL3) Cement l-250 Water 500 Sand
1 000 low strength mortar (
897 m”) Cow mortar 175° bend unit 60 Drum rotation speed (rpm) 10 Stirring/kneading time 3 m (1 unit in the mixer) 2 minutes (2) E Mortar strength des l-piece (Ky/m3) σ3 = 5.1~ 11.0 ■Results Immediately after cross-talk in the mixer, 1 to Remy pipes were poured into the Benaut/excavation hole in the ground, and after 4 El, solidified 1] mortar was excavated from the surrounding ground.

There was no significant resistance to cutting and removal, the cutting condition was good, and the mortar did not collapse.

However, if the mortar strength σ" = 20 to 9/rrt3 or more, cutting with a shield excavator was difficult.

[Effects of the Invention] As described above, in this invention, raw mortar mixed and kneaded in a factory is transported to a work site in a mixer, and at the work site, an additive for reducing strength is added to the raw mortar in a drum. In addition, the rotation of the drum mixes raw mortar with low-strength mortar, so there is no need to prepare plant equipment or materials for mixing at the work site, and since the mixer is used, there is no need to mix wires. Not only does it eliminate the need for complicated setups, but it also significantly improves efficiency by making it possible to mix at a maximum of 90m"/l-1, making it possible to mix at low speeds even in restricted work sites where there is no room for installing plant equipment. It has many advantages such as being able to place strong mortar.

Claims (1)

[Claims] The green mortar mixed and kneaded at the factory is transported to the work site using a mixer truck, and before placing the mortar, additives to reduce the strength of the mortar are added into the drum of the mixer truck, and the rotation of the drum transforms the green mortar. A method for kneading low-strength mortar, which comprises uniformly stirring and kneading additives into low-strength mortar.