SU1125329A1 - Structure base - Google Patents

Abstract

FOUNDATION OF CONSTRUCTIONS, in: ikimy on water-saturated, low-water-resistant ground, including reinforcement zones, characterized in that, in order to increase the reliability of the foundation in the conditions of erection of the hydraulic structures on it, such reinforcement zones are in contact with the foundation of the construction continuous vertical columnar arrays of soil, the humidity of which is determined by the following relationship: Wp - 0.5 (Wn - Wp), 3 (Wn-Wp), where Wn is the humidity at the limit of plasticity of the soil; WP - humidity at the limit of rolling out the soil; W - proper weight of soil moisture. ND СЛ оо to со

Description

The invention relates to hydraulic engineering, in particular to the bases of earth dams erected on water-saturated, low-permeable soil.

The base of an earth dam erected on a water-saturated ground is known, in which vertical drains 1 are made to increase the bearing capacity of the base.

The disadvantage of this base is its low carrying capacity, especially in the junction zones of the free slope of the dam with the base due to its low strength, due to its slow and inefficient. moisture removal by means of Dren.

Also known is the foundation of a structure erected on a water-saturated, low-permeable soil, including reinforcement zones made of hardening material and placed on the base in a fine order of 2.

The known base is characterized by insufficient strength, especially in the zone of its contact with the structure, due to the presence of non-reinforced soil areas along the base depth, which creates conditions for the possible passage of power lines arising from the structure, past reinforced zones.

The purpose of the invention is to increase the reliability of the foundation in the conditions of erection of an earth hydraulic structure on it such as a dam.

The goal is achieved in that the reinforcement zones are made in the form of continuous vertical columnar arrays of soil in contact with the base of the erected structure, the humidity of which is determined by the following relationship:

Wp-0,5fWM - yp), 3),

where Wn-humidity at the limit of plasticity of the soil;

Wp.-Humidity at the limit of rolling out the soil; W is proper weight moisture

ground.

The boundary values of 0.5 and 0.3 characterize the consistency index of the soil J, which is defined as GOST.

When Do, 5. the bonded soil becomes uncomposable and incompressible, with, 3 there is a danger that the soil will develop a threshold pressure when the base is loaded, and, as a result, the load bearing capacity of the soil decreases.

FIG. 1 shows a dam with a base under it, a vertical section; on

FIG. 2 shows section A-A in FIG. one; in fig. 3 - construction in the presence of cylindrical pillars, vertical section; in fig. 4 shows a section BB in FIG. 3

The base 1, made of water-saturated low-permeable soil, includes reinforcement zones 2 filled with low-moisture soil. Based on 1, a structure 3 was erected in the form of an earth dam.

According to the condition of stability of the structure, the carrying capacity is achieved at a certain ratio between the area of reinforced zones and the area of the base. Depending on the soil properties of the base and the soil of the columnar zones and the ratio between them, the minimum allowable value of the value (-THA-j, 0 can be taken within

one,

0s

where 5 and Z-area of the base and columnar

zones, respectively.

The value "O" corresponds to the case when the base has sufficient own bearing capacity, which is minimally acceptable by the condition of stability of the structure. When 1 is necessary

a complete change in the properties of the base soil to a new, accepted level, for example, 0 complete replacement of the soil to the depth of the weakened layer.

The distance between the columnar zones can vary over the area of the base, depending on the strength of the underlying base soils.

Ground moisture is determined by the following relationship:

WP -0.5 {W, - Wp) W Wp + 0.3 (Wn - Wp), where W is the humidity at the limit of plasticity;

Wp is the humidity at the limit of rolling; W - proper weight moisture

ground.

The base of the structure works as follows.

The load from the dam 3 is transferred to the base 1, and is distributed between the weak ground of natural occurrence and the ground of the columnar zones 2. Since the strength of the soil of the columnar zones is higher than the strength of the natural base, the total bearing capacity of the base increases. The use of the invention will make it possible to reduce the volume of land works, if necessary, to replace weak soils and to accelerate the rate of construction of the structure.

FIG. g

Claims (1)

BASIS OF STRUCTURE erected on water-saturated low-permeable soil, including hardening zones, characterized in that, in order to increase the reliability of the base in the conditions of erection of an earthen hydraulic structure like a dam, the hardening zones are made in the form of continuous vertical columnar arrays in contact with the base of the erected structure whose moisture content is determined by the following relationship: Wp - 0.5 (W _ft - Wp) 4W4.Wp + 0.3 (Wn-W _P ), where Wn - humidity at the limit of plasticity of the soil; Wp - humidity at the limit of rolling soil; W is own soil. moisture content (/) FIG. 1