JPS5927022A - Continuous cut-off wall work of cement mortar - Google Patents

Abstract

PURPOSE:To construct an underground continuous wall without the need to discard soil and sand by a method in which excavated soil and sand mixed with a stabilizing liquid for excavation are mixed with a solidifying agent on the ground surface to produce a soil cement, and the soil cement is placed into a vertical shaft. CONSTITUTION:In a sheathing or a water cut-off work, a vertical shaft for an underground continuous wall is excavated. The excavated soil and sand mixed with a stabilizing liquid is mixed with a solidifying agent composed of a mixture of cement, bentonite, a coagulation retarder, etc., in a plant on the ground surface to produce a soil cement. The soil cement is placed into the shaft where an iron bar cage is set to construct a continuous underground wall.

Description

[Detailed Description of the Invention] Conventionally, when constructing an underground continuous wall for mountain retaining or water stoppage,
After excavating a trench hole for constructing an underground continuous wall, disposing of the excavated soil and installing a reinforcing bar cage in the trench, concrete is poured and the excavation stabilizing fluid in the trench is replaced to form a reinforced concrete wall. was building.

Therefore, if the impermeable layer is located at a shallow location, it will be disadvantageous in terms of cost if the underground continuous wall is not used as part of the structure. This can lead to noise and other pollution problems in urban areas.Also, the assimilated strength of stabilized liquids, such as bentonite mud, is low and has a high water content, so the selection range for design strength is small, and strength variations may occur. 11 points in terms of reliability.
was there.

The present invention was proposed in order to eliminate the drawbacks of slope, and the excavated soil mixed with excavation stabilizing liquid generated due to the tll excavation of a vertical trench for constructing an underground continuous wall is mixed with a solidification material at the surface of the ground. This invention relates to a continuous mortar ice-stopping wall construction method characterized in that a fill mortar is produced, and then the fill mortar is poured into the vertical groove to construct an underground continuous wall.

In the present invention, as described above, in mountain retaining and water stop construction, excavated soil mixed with excavation stabilizing liquid during excavation of vertical trenches for constructing underground continuous walls is disposed of. By mixing it with assimilated material in a plant to produce a fill mortar that itself has stable strength, we constructed an underground continuous wall by pouring the fill mortar into the groove, which is different from the conventional T method. It is advantageous in places where underground water pumping is regulated and where the impermeable layer is deep, and it is advantageous in areas where underground water pumping is regulated and where the impermeable layer is deep.
The present invention has many advantages, such as preventing environmental contamination.

As the assimilation material to be mixed with the excavated soil, a mixture of cement and additives such as bentonite, a setting retarder, and granulated blast furnace slag may be used. The formulation of fill mortar is confirmed in advance by trial kneading, but the basic formulation is determined by indoor formulation tests (.

The strength of fill mortar can vary considerably depending on the type and amount of assimilated material, but in general it has an unconfined compressive strength of 10 to 20'9/cm' (28 cm in 20'C water).
After curing for one day), the strength should be low.

Quality control of fill mortar should be performed on workability and strength, and workability is 71.
? The following factors affect the quality of continuous underground wall using fill mortar: In the invention, a Thiemel flow value of 200 to 240 is appropriate.

In the construction method of the present invention, it is important to minimize fluctuations in quality due to changes in the properties of excavated soil, and for this reason, the accuracy of geological surveys by poling and the results of indoor mixing experiments using the samples is 111 points are required.

In addition, when using the underground continuous wall constructed by the construction method of the present invention as a retaining wall, an H-type wall,
■Install the shaped steel into the cast fill mortar with appropriate dimensions and spacing. At this time, if the root cutting depth is large, this construction structure will be constructed using the reverse hammering method.

Next, a description will be given of an embodiment in which the present invention is applied to the construction of a mountain retaining water-stop wall for fire construction foundation work.

As shown in Figure 1, the construction ground consists of loamy tuff clay deposited to a depth of 6 m from the ground surface (1), with fine to medium sand mainly up to a depth of 26 m, and hard silt below that.

Here, the soil excavated from the trench for constructing the water-retaining wall is mixed with solidified soil at a surface plant to produce fill mortar.
After installing a reinforcing bar cage in the trench, the fill mortar was placed to construct a retaining water stop wall (2), as shown in Figure C (3).
) is the frame of the structure.

The mountain retaining water stop wall (2) was constructed with a depth of 28 m, a wall thickness of 0.6 m, and a total circumference of 404 m, which is the planned underground excavation value. In addition, Tonosho and Mizu FE were designed to be mainly borne by H-type steel (RO9QXROCl0x10x16, height 18.Or, spacing 1.25 m).

For the construction VcI type, a vertical groove with a predetermined cross section is excavated to a predetermined depth, and 2 to 6 sets of 5 H-shaped steels are installed in the groove using 5 pieces of H-shaped steel. - With a force excavator as a phrenologist, test line i is 6 (f confirmed in advance)
It was poured into soil mortar grooves using the Nomitscha Plant υC with the mixture specified by C Isugawa Sada.

Table-1 Fill mortar standard formulation However, sand is absolute dry weight. The water content fk of sand shall be 60% or less.

The admixture is a 25% solution, and Formulation 1 is (G+B)xl. 25
% Mixture 2 is (G + B)

Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to such embodiments, and may deviate from the spirit of the present invention and modify God's design within the scope. It is scaly.

4 [Figure (Simplified explanation of A11)] Figure 1 shows the soil quality b3?
Introducing cross-sectional views of Shikoku and underground rental structures, Figure 2 is a table in Figure 1 showing the relationship between depth and compressive strength of underground continuous walls.

(2)... Mountain water stop wall Agent: Patent attorney, Okamoto, Kuruma, 2 other people, 1 illustration 1O1- Horse 2 Wet density ρl (g/c117) Continuation of page 1 0 shots Akinobu Sakako Noboritoso B, 1282 Noborito, Tama-ku, Kawasaki City -No.3

Claims (1)

[Claims] Fill mortar is produced by mixing the excavated soil mixed with excavation stabilizing liquid produced during the excavation of a vertical trench hole for constructing an underground continuous wall with solidified soil on the ground surface, and then pouring the same fill mortar into the vertical trench hole. A continuous mortar ice wall construction method characterized by the construction of a continuous underground wall.