RU2593282C1 - Method for reinforcement of railway road bed on weak base - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to preparation of base for road construction by soil reinforcement. Reinforcement method of road bed track on weak base involves construction of reinforcing device in the form of piles and construction of road bed. Between the surface of a weak base, reinforced piles, and the base of road bed foundation frame are composed of platform thickness 0.3-0.5 m by layer-by-layer compaction of mix of soil with consolidant at a ratio of 0.9:0.1 with tamping humidity 10-15 % to compaction coefficient of 0.95. Thickness of each of laid layer of mixture is 0.08-0.1 m, the soil for the mixture consists of clay, sand with 0.25-0.5 mm fraction, stone particles with 2-5 mm fractions in equal portions.

EFFECT: increasing carrying capacity of a weak base, reduction of material consumption for construction due to use of local non-draining soils.

1 cl, 1 dwg

Description

The invention relates to the construction of roads, namely to the preparation of the foundation by strengthening the soil.

The construction of the road base is known (AS USSR No. 601343, class Е01С 3/04. V.A. Davydov, V.Ya. Pinigin, Yu.G. Slyunkov. Base of the road and airfield pavement. - Publish. 04/05/1978 ), including compacted soil, placed in a shell of soil reinforced with a binder.

The disadvantage of this design is the lack of bearing capacity, since the strength of the binder depends on temperature changes.

The closest in technical essence to the proposed method is a method of hardening a weak natural base (Pat. RF 2449075, IPC E01C 3/04. S. Ya. Lutsky, VA Shmelev, A.Yu. Burukin. A method of hardening a weak natural base for the construction of the road subgrade. - Publish. 04/27/2012), including the construction of a reinforcing device in the form of soil piles, consisting of a shell filled with drainage material, surface vibration compaction, adding sand between piles, reinforcing the inter-pile geotextile.

The disadvantage of this method is the low bearing capacity of the soil reinforced with geotextiles due to the formation and development of base deformations under the influence of transport loads.

The aim of the invention is to increase the bearing capacity of a weak base and cheaper construction by using local non-draining soils.

This goal is achieved by the fact that a grillage is arranged between the surface of the weak base and the base of the subgrade.

The essence of the invention lies in the fact that between the surface of a weak base reinforced with piles, and the base of the subgrade, a grillage is arranged in the form of a platform with a thickness of 0.3-0.5 m by layer-by-layer compaction of the soil mixture with a polyfilizer in a ratio of 0.9: 0.1, having a ramming humidity of 10-15% to a compaction coefficient of 0.95, while the thickness of each stacked layer of the mixture is 0.08-0.1 m, and the soil for the mixture consists of clay, sand fractions of 0.25-0.5 mm, stony particles of fractions of 2-5 mm, taken in equal shares.

In FIG. 1 is a diagram of the reinforcement of the subgrade of a railway track on a weak base, including a weak base 6 reinforced with piles 5, a grillage 4 made from a mixture of soil with a polyfilizer, a subgrade 3, a ballast prism 2 and a rail-sleeper 1.

The proposed method is as follows.

In the presence of weak soils at the base of railway embankments, deformations of the base are observed that continue for a long time after construction and lead to deformations of the subgrade (immersion of the embankment into the base, “creeping”, cracking in the subgrade, uneven subsidence, creep of slopes). In turn, deformations of embankments lead to a disorder of the upper structure of the path (unacceptable elastic deformations, theft of rail threads).

Thus, the presence of deformations of embankments on weak bases not only leads to an increase in operating costs, but also reduces the safety of train traffic in these sections.

The weak base 6 of the subgrade 3 is reinforced using special equipment with piles 5 from the soil of the weak base 6 and binders, by simultaneously introducing the binders into the base soil and mixing them with the base soil, resulting in load-bearing ground piles. Next, the grillage 4 in the form of a platform with a thickness of 0.3-0.5 m is laid on a reinforced base by layer-by-layer compaction of the soil mixture with a polyfilizer. The soil for the grillage device should consist of clay, sand fractions of 0.25-0.5 mm, rocky particles of fractions of 2-5 mm, taken in equal proportions. A soil mixture with a polyphilizer is prepared in a ratio of 0.9: 0.1 with a ramming humidity of 10-15%. This mixture can be laid ready-made or mix the soil directly at the construction site. On a weak base 6 reinforced with piles 5 over the entire width of the bottom of the subgrade 3 lay a mixture of soil with a polyphilizer, each layer with a thickness of 0.08-0.1 m, and compact each layer to a compaction coefficient of 0.95 rollers weighing at least 14 tons .

Stacked grillage 4, by soaking the soil with a polyfilizer, becomes water-repellent as it compacts, which allows the use of local non-draining soils for the construction of subgrade 3. This eliminates the cost of draining soil, which is traditionally used in the construction of subgrade on weak substrates, and also significantly reduces soil transportation costs.

As soon as the grillage 4 is ready for the required thickness, a subgrade 3 of non-draining soils is constructed, onto which the upper track structure is laid in the form of a ballast prism 2 and a rail-sleeper grid 1. It should be noted that the configuration of the main platform of the subgrade and the steepness of the slopes of the subgrade are determined by SNiP 32 01-95 "Railways gauge 1520 mm" for non-draining soils.

The rail-sleeper grid 1 is laid on the ballast layer 2, which, in turn, transfers the load to the subgrade 3. A grill 4 is arranged between the surface of the weak base 6 and the base of the subgrade 3, which evenly distributes the transport load to the piles 5, as a result of which the bearing increases subgrade ability 3.

Thus, the proposed method allows, using well-known techniques and materials, to solve problems associated with the bearing capacity of the subgrade design in difficult operating conditions, with the possibility of cheaper construction due to the use of local non-draining soils.

Claims (1)

A method of reinforcing the subgrade of the railway track on a weak base, including the construction of a reinforcing device in the form of piles and the construction of the subgrade, characterized in that between the surface of the weak base reinforced with piles and the base of the subgrade, a grill is made in the form of a platform with a thickness of 0.3-0, 5 m by layer-by-layer compaction of a mixture of soil with a polyfilizer in a ratio of 0.9: 0.1, having a ramming humidity of 10-15% up to a compaction coefficient of 0.95, while the thickness of each stacked layer of the mixture is 0.08-0.1 m, and the soil for the mixture consists of clay, sand fractions of 0.25-0.5 mm, rocky particles of fractions of 2-5 mm, taken in equal proportions.

Images