RU1774975C - Earth strip on weak base - Google Patents

Abstract

Usage: in the construction of embankments of roads on marsh and other weak soils. The invention improves the strength and stability of the subgrade by laying a layer of flexible synthetic non-woven material at an angle to the axis of the road, which makes it possible to maximize the strength characteristics of the layer. The anchoring strength also increases by introducing it into the body of the embankment at the same angle to the axis embankments, but in the opposite direction with respect to the position of the layer in the base of 4 silt,

Description

(L

WITH

The invention relates to the construction and can be used in the construction of embankments of roads on marsh and other soft soils

. A road bed on a weak foundation is known, including an embankment of mineral soil laid on a weak foundation. A disadvantage of the known subgrade is the unevenness of the subsidence of the base, the long term of its consolidation.

Closest to the proposed subgrade is a weak base, including a mound of mineral soil laid on a layer of synthetic ntwoven material placed on the base.

Design shortcomings - the incomplete use of strength svig.gv non-woven synthetic material m which

it has different strengths in the longitudinal and transverse directions, as well as weak anchoring of the interlayer in the base, which does not provide sufficient strength and stability of the subgrade.

The purpose of the invention is to increase the strength and stability of the subgrade

This goal is achieved by the fact that in a subgrade on a weak foundation, including a mound of mineral soil, laid on a layer of synthetic non-woven material placed on the base, a layer of flexible synthetic material is laid on the base at an angle a1s1 P / Q to the axis of the mound and introduced into the body of the embankment in the opposite direction with respect to its position in the base at the same angle (P and Q are the strength of the synthetic material of the interlayer in

M Ј b

IsQ, V |

ate

with

longitudinal and transverse directions, respectively).

In FIG. 1 shows a subgrade on a weak base, cross section; figure 2 - scheme of laying synthetic non-woven material on a weak base; in Fig.3 is a diagram of the laying of synthetic non-woven material on the surface of the embankment; Fig. 4 is a diagram of the action of forces on an interlayer.

A subgrade on a weak base includes a mound 1 of mineral soil, a layer 2 of synthetic non-woven material, which is laid on the base 3 at an angle a arctg P / Q (P and Q are the strength of the synthetic material of the layer in the longitudinal and transverse directions, respectively) and introduced into the body of the embankment in the opposite direction with respect to its position at the base at the same angle.

The angle a, at which the layer is laid relative to the axis of the embankment, is defined as follows. It is known that the higher the stiffness of the embankment, the more uniformly distributed are the deformations of the weak base over the cross section of the embankment. The rigidity of the embankment can be increased by increasing the strength of the interlayer in the plane of the cross section of the embankment.

Since synthetic non-woven materials have relatively low strength characteristics, they can be increased if the load is applied at a certain angle a to the longitudinal axis of the web so that it is maximum in the plane of the cross section of the embankment. From the consideration of the action of forces on the interlayer (Fig. 4), it follows that the resultant N of these forces will be located at an angle a whose tangent is equal to the ratio P / Q (or a-arctg P / Q), where P and Q are the strength of the synthetic material interlayers in the longitudinal and transverse directions, respectively.

Comparison with the prototype shows that this subgrade differs from the known one in that the synthetic non-woven material is laid on the base at an angle a, i.e. The claimed subgrade meets the criterion of novelty.

Technical solutions are known in which a layer of synthetic non-woven material is laid on the base, however, the location of the layer at an angle a to the base and the insertion of the layer into the body of the embankment in the opposite direction to its position in the base under the same

angle enhances the anchoring of the interlayer and helps to increase the rigidity of the embankment, the strength and stability of the subgrade. This allows us to conclude that it meets the criterion of significant differences.

The subgrade on a weak base works as follows.

Synthetic non-woven interlayer

0 of the material, laid on the base at an angle a, perceives the load from the weight of the embankment, equal to the algebraic sum of the forces perceived by the interlayer in the longitudinal and transverse directions. This total load is greater than separately taken longitudinal and transverse. The introduction of the layer into the body of the embankment in the direction opposite to its position at the base, at the same angle, strengthens

0 anchoring of the interlayer and contributes to an increase in the rigidity of the embankment, which leads to a redistribution of stresses along the cross section of the embankment from its axis to the edges. In addition to increasing the strength and stability of the subgrade, this leads to equalization of sediments along the embankment cross section,

The use of the subgrade of the proposed design will increase the strength and stability due to laying

0 interlayers at an angle to the axis of the road, which allows maximum use of the strength characteristics of synthetic non-woven material. In addition, the anchoring strength of the interlayer increases

5 by introducing it into the body of the embankment at the same angle to the axis of the embankment, but in the opposite direction with respect to the position of the interlayer at the base.

The presence in the construction of the ground layer of synthetic non-woven material ensures the separation of the mineral soil of the embankment and the weak, for example peat, soil of the base and does not allow them to mix.

5 Improving Tc also conditions the compaction of the lower layers of the embankment, sediment is smoothed out and the relative overload from the middle part of the embankment to its marginal zones is reduced.

0

Claims (1)

SUMMARY OF THE INVENTION A ground web on a weak base, including an embankment of mineral soil, laid on a layer of synthetic non-woven material placed on the base, characterized in that, in order to increase the strength and stability of the earth, a layer of flexible synthetic non-woven material is laid on base at an angle a arctg P / Q, where P and Q are the strength of the synthetic fill in the opposite direction material layer in longitudinal with respect to its position at the base the lateral and transverse directions to the osipod at the same angle, the embankment, respectively, and is led into the body FIG. 2 F.1G. 3 -X FIG 4.