SU1027312A1 - Method of erecting cellular retaining structures on hard rock beds - Google Patents

Description

to

with

ts

2, the method according to claim 1, characterized by the fact that the thickness of the layer of highly deformable soil is determined by the formula

t7 / 4

V

about

thickness of the layer of highly deformable soil;

the maximum amount of displacement of the backfill soil,

which fully develop contact friction forces between the filling ground and the cell wall;

modulus of deformation of a strongly deformable material;

the mean vertical stress across the cross-sectional area, experienced by a layer of highly deformable material from the underlying layer of backfill soil;

full height of the cellular structure.

1 I

FIELD OF THE INVENTION The invention relates to construction, mainly hydraulic engineering, road traffic.

There is a known method of erecting a foundation under a structure on weak, water-saturated soils, including the construction of an impervious curtain that restricts weak soil along the entire perimeter, a coating of waterproof material located on the surface of the weak soil, and soil backfilling.

The main element of this method is the implementation of a waterproof layer, which eliminates the time spent on compacting the soil of a weak base and the need to use high-quality sand for the installation of soil backfilling. 1 13 However, this method does not improve the shear stability of structures.

The closest in technical essence to the present invention is a method for erecting cellular retaining structures on a rocky foundation, including installing it on the base and then filling them with soil 2. .

However, this method has a disadvantage. That is, it does not allow the shear stability of the structure to be maximized. It is known that the backfill soil at 5080 determines the shear stability of the structure. And the larger part of it

hangs on the walls of the frame,

by that

a more stable shear structure, since the coefficient of friction at the base of the structure between the base rock and the concrete of the framework is much higher than that between the filling ground and the rock base 0.5-2.0 times).

The aim of the invention is to increase the shear stability of the structure by increasing the degree of soil sticking to the cell walls and increasing the value of the coefficient of friction between the ground and the walls.

The goal is achieved by initially filling the soil with a layer of 0.1-0.2 of the height of the structure, after which a layer of highly deformable soil is filled with it, and then the cells are filled to the top with the soil of the filling.

The thickness of the layer of highly deformable soil is determined by the formula

thickness of the layer of highly deformable soil;

the maximum amount of displacement of the soil of the filling at which it is complete. contact friction forces develop between the filling ground and the cell walls; 3 Е - modulus of deformation of a strongly deformable material; (is the average for the cross sectional area of the vertical stress experienced by the layer of highly deformable material from the overlying layer of the backfill soil; H is the full height of the cellular structure. The drawing shows the cell with the backfill soil. The proposed method involves making a skeleton from cells 1 on the rock base 2, followed by filling in layer 3 of the strongly deformable material k and material of filling 5 filling ki 1 to the entire height of the structure. The size of the initially filled layer of filling is analytically determined and taken equal to (0.1-0.2) H, based on the coefficient of contact friction between the rock base and the backfill material 0.7 and from the condition that the cell size is 1.7-3.5 times smaller than the height of the foundation. A layer of highly deformable soil can be dusty sand, moist clay, etc. The presence of a layer of highly deformable material maximizes the degree of soil sticking due to the development of contact friction between the backfill soil and the cell walls. This effect of the development of contact friction forces is caused by the fact that a strongly deformable layer allows the ground to shift from the weight of the overlying layer (regardless of the deformative properties of the backfill soil) relative to the walls of the cell, which leads to the development of full contact force. At a certain thickness of the layer of highly deformable soil, contact friction forces can be fully developed along the entire height of the structure. The tests that have been made show that by making a layer of highly deformable soil, the degree: sticking of the backfill soil on the walls can increase by 10-20% relative to the total weight of the backfill soil. This leads to an increase in the stability coefficient for the shift of the cellular support structure by 5-10 without additional costs. As a result, the application of the invention allows to reduce the thickness of the cell walls and save the amount of concrete, and, consequently, the cost of construction as a whole. If it is impossible to reduce the thickness of the walls of the cell due to the condition of maintaining their allowable stress state, savings can be achieved by reducing the volume of the soil.

Claims (2)

1. METHOD FOR CONSTRUCTING CELLULAR SUPPORT STRUCTURES ON A ROCKY BASE · Including installation of cells on a base with their subsequent filling with soil, distinguishing menko (71) of the Moscow Order of the Red Banner of Labor, Irrigation and drainage institute (53) 624.152 (088.8), therefore the purpose of increasing the shear stability of the structure by increasing the degree of soil hovering on the cell walls and increasing the coefficient of friction between (56) 1. USSR author's certificate K 773206, cl. E 02 D 27/36, 1978. 2, Varkhobov TP ’Prefabricated monolithic and prefabricated cellular dams. M., 1962,. · S. 75 "7b (prototype). with soil and walls, initially fill soil with a height of 0, ΙΟ, 2 of the height of the structure, after which a layer of highly deformable soil is dumped on it, and then the cells are filled to the top with filling soil. 2. The method of pop. 1, characterized in that the thickness of the layer of highly deformable soil is determined by the formula P about where t -! layer thickness of highly deformable soil '; D _CR - the limit value of the displacement of the soil backfill, at which fully develop the force of contact friction between the soil backfill and the cell wall; E is the deformation modulus of a highly deformable material; b - the average vertical cross-sectional area voltage experienced by a layer of highly deformable material from an overlying layer of backfill soil; H is the total height of the cellular structure. ii