SU1217984A2 - Apparatus for producing lateral pressure tri-axial compression testing of large-lump soil - Google Patents

Description

The invention relates to the construction, namely, the technique for testing predominantly coarse soils for triaxial compression, can be used both in field and in laboratory conditions, and is complementary to auth. No. 966148.

The aim of the invention is to improve the accuracy of measurements and the expansion of functionality.

FIG. 1 shows a device, a longitudinal section; in fig. 2 - the same, cross section; in fig. 3 shows the node I in FIG. 1 (detail of the spacer I on the casing and flexible waterproof shell).

The device for creating lateral pressure when testing for three-axis compression includes a rigid lobe 1 of cylindrical shape and an elastic plate 2, which encloses one lobe on the inner side. Plate 2 is attached to the petal 1 at both ends using the top 3 and bottom 4, provided with a knife, clips. The petals 1 are interconnected along the lateral surface with the help of the corners 5 and the bolts 6, which are welded to them from the outside. The remaining (unattached) sides of the plates 2 are clamped in places of the interfacing of the lateral surfaces. The petals 1 are interconnected in such a way that, at the junction points, the surface is convex from one element and concave from the other.

Spacers 7 installed in the internal cavity of the device consist of separate split elastic rings 8 placed in the annular grooves of shaped elastic elements 9, and firmly press the elastic plates 2 to the hard petals 1, the section of the plate 2 on the horizontal Rus.

The first elastic ring 8 is set into a shaped elastic element arbitrarily, and then with a displacement of the joints of the rings 8 relative to each other along the circumference. The position of the spacers is adjusted to the height of the working chamber in accordance with the thickness of the layers of the complex base. Thus, between the cake 1 and the plate 2, a chamber 10 is created, which is divided by spacers along the 7 themselves into separate Rus, into which they are served under the necessary pressure

ten

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through fitting 11 liquid or

gas to create lateral pressure inside the working chamber 12. All closed chambers 10 within one horizontal plane are hydraulically connected to each other (not shown). When water saturated soils are tested from the side of the free end, the device is equipped with a flexible waterproof sheath 13 with a valve 14 attached by a spacer som 7 to the elastic plate 2.

The device works as follows.

In pale-yellow conditions, spacer 7 is mounted to the assembled and ready-to-work device (Fig. 1), the position of which is established in accordance with the preliminary data on the base layer, and installation of spacer 7 begins with the installation of a shaped elastic element 9 in which grooves are mounted one by one split elastic

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| ring 8 so that their joints are offset relative to each other along the circumference. Due to the action of the knives and its own weight, the device is inserted into the ground. When testing the water of its soils after immersing the device 3 / 4-4 / 5 on the side of the free end, a flexible waterproof shell 13 with a valve 14 is installed, which is sealed to spacer 7 to the elastic plate 2. For. Further immersion of the device, the soil entering the working chamber 12 displaces the air from it through the valve 14. To increase the rate of introduction, it is possible to remove excess soil around the device. After immersion, the unnecessary level through choke 1 1 into the Rus of the closed chambers 10 is supplied under the pressure or pressure set by the test pressure, taking into account the properties of the various layers of the complex base.

When testing in laboratory conditions, it is sufficient to set the device on a flat, smooth surface with knives up or down. In this case, the spacers of the sa 7 are installed in accordance with the thickness of the layers of the complex base placed in the working chamber 12 of the device. Flexible waterproof shell 13 when testing the water

Soils are mounted after filling the working chamber with 12 soil.

When using the proposed device, the measurement accuracy is improved when determining the characteristics of soils due to more accurate modeling of the stress state of the layered base by creating lateral pressure close to

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to the natural for each layer of soil separately. In addition, when testing water-saturated soils, groundwater is filtered 5 only through the lower base, which corresponds to the natural conditions of filtration, and also contributes to an increase in the accuracy of determining the characteristics of the soil.

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sri.Z

Editor M.Kelemes

Compiled by G. Martynova

Tehred O. Niece Proofreader E. Sirohman

1091 / 36Care 642 Subscription

VNIISH State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, Proektna St., 4

Claims (3)

1. DEVICE FOR CREATING LATERAL PRESSURE AT TEST ON A THREE-COMPRESSION OF A LARGE-BLOCKED SOIL by ed. No. 966148, characterized in that, in order to increase the accuracy of measurements and expand the functionality, the device is additionally equipped with integral spacer belts located in the internal cavity of the device for dividing the elastic shells into tiers, and the spacer belts are installed with the possibility of their movement in height the internal cavity. 2. The device according to p. Characterized in that it is additionally equipped with a flexible waterproof shell, hermetically pressed by a spacer belt to the elastic petals from the side of the free end of the device, while the flexible waterproof shell is made with a valve. 3. The device according to p. ^ Characterized in that it is equipped with shaped elastic elements with annular grooves, and the spacer belts are made of separate split elastic rings and are installed in the annular grooves of the shaped elements, and the joints of the elastic rings within one belt are offset relative to each other in length circles. figure 1 1217984 ¹ through the nozzle 11 with liquid or gas to create lateral pressure inside the working chamber 12. All closed chambers 10 within one j horizontal tier are hydraulically interconnected (not shown). When testing water-saturated soils from the free end side, the device is equipped with a flexible waterproof membrane 13 with a valve 14 attached by a spacer belt 7 to the elastic plate 2. The device operates as follows. ₍₅ In the field, in the assembled and ready for operation device (Fig. 1), spacer belts 7 are mounted, the position of which is set in accordance with preliminary data 20 about the layering of the base, and the installation of the spacer belt 7 begins with the installation of shaped elastic element 9, in the grooves of which are mounted one at a time split elastic 25 (rings 8 so that their joints are displaced relative to each other along the circumference. Due to the action of the knives and their own weight, the device is embedded in the ground. When testing water-saturated soils after ³⁰ immersion, the devices are set to 3 / 4-4 / 5 from the side of the free end flexible waterproof shell 13 with a valve 14, which is hermetically fastened with a spacer belt 7 35 to the elastic plate 2. Upon further immersion of the device, the soil entering the working chamber 12 displaces air from it through the valve 14. To increase the penetration rate ⁴⁰ , excess soil around the device can be removed. After immersion, an unnecessary level through the nozzle 1 1 in the tiers of the closed chambers 10 is fed under the set for testing 45 pressure liquid or gas, given the properties of the various layers of a complex base. When tested in ⁵⁰ labo-valued conditions sufficient to install the device on a flat smooth surface knives upwards or downwards. When this spacer belt 7 is set in accordance with the thickness 55 layers of a composite base placed in the working chamber 12 of the device. Flexible waterproof shell 13 when tested water-saturated