JPH03287909A - Backfilling and packing work - Google Patents

Abstract

PURPOSE:To prevent the occurrence of subsidence by a method in which excavated soil is mixed with a hardening agent and carried to an embedding site, and the soil is fluidized with water supplied, subjected to vibration and packed into the backfilling site. CONSTITUTION:Excavated soil is mixed with about 5wt% hardening agent such as cement and carried along to a backfilling site. The soil is supplied with about 10% or more water while packing into the backfilling site and fluidized by a vibrator to pack it into the site. The backfilling work can thus be completely attained to prevent the occurrence of subsidence of the ground.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for burying or repairing water pipes, sewer pipes, gas pipes, etc., or backfilling excavated areas during construction work of structures.

[Prior Art] Generally, it is desirable to backfill excavated areas during burying and repair of water and sewage pipes, gas pipes, etc. or construction of structures using excavated soil, but if the remaining soil is inappropriate, separate It is common practice to use good quality earth and sand, or to use improved soil made by adding a hardening agent to the excavated soil, and to thoroughly compact the soil.

[Despite the problems that the invention seeks to solve, in reality, in such construction and civil engineering work, it is difficult to sufficiently ram the pipes, especially around pipes, and the ramming tends to be loose and cavities remain.] be.

For this reason, there are problems such as causing ground subsidence and cave-ins at a later date.

In order to solve such problems, for example, Japanese Patent Application Laid-Open No. 1-31
As described in Publication No. 2118, a method has also been attempted in which the excavated soil is mixed with a solidifying agent and water to create a slurry of fluidized treated soil. Mixing and agitation is carried out by an on-site plant installed at the construction site or a ready-mixed concrete plant, so it is extremely difficult to secure a plant yard on a narrow site. However, there are problems such as the process is complicated and the cost is high. .

Therefore, this invention can be used at backfilling sites with excavated soil.
The purpose of this method is to obtain a fluid backfill material using a simple method, and the process of adding a solidifying material to excavated soil and the process of adding fluidity by mixing water etc. are separated, and the process of adding fluidity to the excavated soil is separated. The key point of this method is to perform mixing and fluidization through water injection and vibration during the backfilling process.

[Means for Solving the Internal Problems] In order to achieve the above-mentioned object, according to the present invention, during excavation and backfilling work in construction work, a solidification material is mixed in advance with the excavated soil, and this treatment is carried out. The treated soil is transported to the backfilling site, water is poured into the treated soil, and the treated soil is fluidized by vibration, thereby completely filling the backfilling area.

[Function] Accordingly, the present invention uses the above-mentioned means to mix the excavated soil with a solidifying agent and water in advance in order to reuse the excavated soil as fluid treated soil during excavation and backfilling work in construction work. Addition of such substances is a necessary step, and in particular, the mixing of solidifying materials requires large equipment such as tanks. Therefore, this step should be carried out away from the backfilling site and concentrated in a vacant lot near the backfilling site. Even if the excavated soil has a high moisture content and is soft, in many cases cement is used as a solidification agent by weight of about 5%.
By adding approximately 50% and mixing thoroughly, it can be used as backfill soil. The treated soil treated in this way is transported to the site, and while being backfilled, water is poured into the treated soil using water with a low I content of about 10% or less, and the water is vibrated with a vibrator to make it fluid and fill the backfilling area. Backfilling is performed. In this way, fluidization eliminates the need for compacting the treated soil,
The area around the pipe is also filled sufficiently. In addition, the water injection and vibration application in such backfilling can be adjusted by the worker while observing the properties of the treated soil during construction, and it is easy to adjust the amount of water to the minimum necessary, especially when It is possible to minimize fluidization only in areas where filling is likely to be insufficient, such as around pipes, which is extremely practical.

[Example] An actual example of the backfilling method of the present invention will be explained using an example of a site where a sewer pipe is buried. Water content ratio w=73.5
%, sand content of 32%, silt content of 51%, and clay bone of 17%.The excavated soil generated from the excavation of one site was piled up in the open at a vacant lot 50 meters away from the site. When the sewer pipe installation is completed, approximately 5% by weight of cement is added as a solidifying agent to the above-mentioned open piled surplus soil, thoroughly mixed with a backhoe, and then transported to the backfilling site using a dump truck and dumped. ) Backfilled.

Backfill soil should be placed from the bottom of the excavated trench to the top of the buried sewer pipe2.
Water was injected to a depth of 0 cm), and at the same time, vibration was applied using a rod-shaped vibrator. It was confirmed that the soil around the sewer pipe had been sufficiently fluidized and was completely in contact with the wall of the sewer pipe, ensuring complete filling. At this time, the total amount of water injected was approximately 8.1% of the weight of the original soil, which was considerably smaller than the 15% mixing water for the fluidized treated soil that was initially mixed in a mixer in the test room. This clearly proves that it was possible to fluidize efficiently.

[Effect of the invention] According to this invention, when backfilling excavation work in construction work, a solidifying agent such as cement is mixed in advance with excavated soil, and this treated soil is backfilled. It is possible to completely fill the backfill area by transporting it to the site, pouring a small amount of water onto the backfill straw, and applying vibration using an appropriate vibrator to fluidize the backfill. By using water and fluidization, good backfilling can be completely achieved, and there is no fear of cave-ins or ground subsidence, and the construction can be carried out economically and efficiently in a short period of time.

Claims (1)

[Claims] When backfilling excavations during construction work, a solidification material is mixed in advance with the excavated soil, the treated soil is transported to the backfilling site, and during backfilling, water is poured into the treated soil and vibration is applied. A backfilling method characterized by fluidizing and completely filling the backfilling area.