Device for complex determination of physical and mechanical properties of soils under field conditions
SUBSTANCE: device for complex determination of physical and mechanical properties of soils under field conditions includes an anchor, a thrust beam, a load screw, a turning wheel, an impeller and a cutting ring. In order to enlarge functional capabilities and improve measurement accuracy, it is equipped with a servo drive with a screw, which is installed on the thrust beam, a torque sensor fixed on a tie rod with a circular die, a force sensor fixed in lower part of the servo drive, a vertical movement sensor installed at a reference point. The servo drive, the force sensor, the torque sensor, the vertical movement sensor are connected to the control unit and through an interface to a computer, thus forming a measurement system with direct and feedback communication between the sensors and the servo drive.
EFFECT: improving accuracy of loading and measurement by automatic control of performed tests.
5 cl, 1 ex, 5 dwg
The technical field
Determination of mechanical properties of soils in field conditions when carrying out engineering-geological survey and the survey of soils at the base of the existing foundations.
The level of technology
Similar to the proposed technical solution is "Installation for testing of rock and soil half-rock ring entirely using anchor" (P-43-89. Recommendations for the characterization of rheological properties of rock and soil half-rock method annular loading. L., VNIIG them. BE Vedeneeva, 1990, 4, 6, p.16-17 [H1]), including anchor, resistant frame, mortgage h-beam, hydraulic jacks, concrete formers, the o-ring rear sight, gauges.
The disadvantage of this analogue is that this device is cumbersome, as it is proposed to use for field testing of rock and soil half-rock with the ring entirely diameter of 1 m To create a tangential load is used bond I-beam and two hydraulic Jack, and the beam is placed in a pre-drilled cavity through a circular pillar, the jacks should be resting on concrete blocks. Such a scheme of loading of the tangential load is impossible in clay and sandy soils because of their low strength and you the Oka compressibility.
The following analogue of the claimed technical solution is the Way soil testing" (USSR author's certificate SU 657315 A1, the application 2362128/25-28 from 17.05.1976, IPC5G01N 3/08, G01N 3/22, the applicant Moscow order of the red banner of Labor Institute of civil engineering them. V.V. Kuibyshev, author V.L. Kubacki published 15.04.1979 [C2]), namely, that on the ground set ring stamp, create compressive and torsional force, measure them and judged by the data obtained properties of the soil, characterized in that to increase the accuracy when testing the rocky soil used stamp with smooth transitions to the ground, which is rigidly fastened to the latter.
The method is as follows.
On-site soil set ring stamped with smooth transitions to the ground and rigidly fasten it with the soil, for example, directly on ground concrete manufactures used stamp. The stamp is provided by loading, for example, Jack stops and space.
Then using a system of nagrujala, for example, jacks, create a compressive force on the ground, and torque create, acting on the lugs so that the line of action of the efforts of the parallel tangent to the surface of the stamp. Measure the force on the ground, and judged by the data obtained properties of the soil. The method by which allows us to judge the strength of the surface layers, but about the strength of the deep layers of the soil, which improves the accuracy of determination of the soil properties in General.
The disadvantage of this analogue is that it lacks the ability of the test management system nagrujala that it is not possible to conduct tests with continuous loading at a given speed of deformation. The second disadvantage is the lack of a system for automated recording of measurement data compression and torque effort during testing, which reduces the accuracy and performance tests.
The closest analogue (prototype) of the proposed technical solution is UNIVERSAL INSTALLATION VSEGINGEO (Handbook of engineering Geology, 3rd edition, revised and enlarged, edited by M.V. Churinova, M., Nedra, 1981, RES, str [L3]), containing frame-anchor, thrust beam, the load screw, dynamometer, a swing arm with a dynamometer, a rotating ring, the impeller or cutter ring, the outrigger.
The unit is designed to determine the strength parameters of sand and clay and rocky soils on the surface and in the pits methods pie slice rocks on kropielnicki surface, and also to cut out the large array of samples of cylindrical shape into a ring-holder.
The disadvantage of the prototype is the inability of b is greater vertical displacements of the rotating ring, the impeller or blade ring due to limitations of the design console resistant beams. The second disadvantage is that the vertical load is created by a hydraulic Jack, which necessitates continuous monitoring of the pressure in the cylinder due to his fall due to rainfall rotary ring, which is time-consuming to perform in manual control mode loading. A significant drawback is that the measurement of the vertical displacement, load and torque is performed manually, which reduces the performance and accuracy of the test. The next disadvantage of the prototype is that in the process of testing are determined by only two strength characteristics of soil angle of internal friction and the power unit clutch, while there is a need to determine the characteristics of the strain.
The essence of the technical solutions
A device for testing of soils in the field, including anchor, thrust beam, the load screw, the rotary ring, the impeller and the cutter ring for soil testing in the field.
The purpose of the invention is to enhance the functionality, improving the accuracy of loading and measurement by automatic control test.
Put the spruce is achieved by for vertical load applied to the servomotor, and the creation and regulation of the speed of application of the vertical load is computer controlled via the control unit of force sensors and motion.
For the perception of the reactions of the vertical load applied two anchor and folding beam.
To improve the accuracy of the creation of the tangential load the torque measurement is performed by using the console and sensor strength.
To measure the propagation velocity of the shear wave in the anchor introduced the accelerometer.
To extend the functionality of the device introduced round and coil stamps, probe, which allows to define additional mechanical characteristics of soils, such as modulus of elasticity and strain, shear modulus. Determination of the parameters of the deformability of the soil will be performed in accordance with GOST.
List of figures, drawings and other materials
1 shows a General view of the design device for an integrated evaluation of physical and mechanical properties of soils in the field.
Figure 2 shows the block diagram of measurement.
Figure 3 shows the design of the folding of the thrust beams.
Figure 4 shows the design axial loading.
Figure 5 shows a design of circular stamp with sensor spinning is his moment.
An example implementation of the proposed technical solutions
In figure 1, 2, 3, 4, 5, the device comprises two screw anchor 1, a collapsible thrust beam 2, on which are fixed the servo 3 screw 4, on the lower part of the fixed force sensor 5. Sensor torque measuring 6 by means of the rod 7 is connected with a circular stamp 8. The device contains a set of interchangeable accessories: circular stamp 8, round stamp 9, screw the stamp 10, the penetrometer 11, a transmitter 12, the impeller 13, the sampler 15.
In the lower part of the inside of the anchor 1 has a three-dimensional accelerometer 16, the power amplification and conversion of the signals into a digital form 17, which via wireless or wired connection connected to the control unit 18 via the interface 19 to the computer 20.
On the upper part of the rod round stamp 9 fixed, movable console 21, which supports the rod sensor vertical displacement 22 fixed to the holder 23 and the frame 24. The motion sensor 22 is connected to a wireless or wired connection to the control unit 18.
The torque sensor 6 with handles 25 mounted on one of the rods 7 and connected to a wireless or wired connection to the control unit 18 via the interface 19 to the computer 20.
In the upper part of the screw anchor 1 has a grip 26 for connection with the thrust beam 2.
The thrust beam 2 consists of two folding pipe 27 at stake is Oh which there are support bars 28, serve as the focus for installation in the grip 26. The holder 29 is designed for installation servo 3 with screws 4, as well as for fixing it collapsible tubes 27 of the thrust beams 2. In the working position of the beam 2 folding pipe 27 are connected by a locking pin 30. The frame 24 includes a holder 32 for the installation of motion sensor 33.
The torque sensor 6 has a force sensor 34 and the console 35, which is fixed on one of the handles 25.
The device operates as follows.
Step 1. Prepare your device for testing
1. On the ground surface, the bottom of the trench or pit, using servo 3 screw 4, in the ground wrapped two screw anchor 1 at a distance equal to the distance between the slats 28 of the thrust beam 2.
2. The thrust beam 2 is fixed by screws 31 in the hooks 26 on the anchors 1.
3. The actuator 3 is fixed on the holder 29 in the Central part of the thrust beam 2 and is connected to the control unit 18.
4. On the surface of the ground set the frame 24 and attach the holders 23, 32 displacement sensors 22, 33. Rod motion sensor 33 is installed in any location on the surface of the thrust beams 2. The displacement sensors connected to the control unit 18.
The readings of the displacement sensors 33 allow us to estimate the deflection of the thrust beams 2, which is included in the measurement of vertical movement or the nogo device.
5. Force sensors 5, 34, displacement sensors 22, 33 connected to the control unit 18.
6. The control unit 18 via the interface 19 is connected to the computer 20.
Step 2. The implementation of automatic test method and sequence testing
1. Choose the type of device for testing soil: round stamp 9, screw the stamp 10, the penetrometer 11, a transmitter 12, the impeller 13, a circular stamp 8 or sampler 15.
2.1. Test round stamp with the area of 600 cm2
2.1.1. Round stamp set on the soil surface coaxially with the screw 4 and using the holder 23, fix the motion sensor 22 so that the rod rested on the movable console 21.
2.1.2. Using the methodology GOST 20276-99 section 5 [L4], test stamp. Measurement of precipitation stamp and load control automatically, using the readings of the displacement sensors 22, the force sensor 5 and the actuator 3. Measurement data are entered into the database of the computer.
2.1.3. Using the results of measurements on paragraph 5.5.2 GOST 20276-99, find the modulus of deformation of the soil.
2.2. Testing coil stamp area of 600 cm2
2.2.1. Screw the stamp set on the soil surface coaxially with the screw 4 and using the holder 23, fix the motion sensor 22 so that the rod rested on the movable console 21.
2.2.2. Using the methodology GOST 20276-99 section is 5, test stamp. Screwing stamp in the soil and the application of the vertical load is carried out using servo 3. Measurement of precipitation stamp and load control automatically, using the readings of the displacement sensors 22, the force sensor 5 and the actuator 3. Measurement data are entered into the database of the computer.
2.2.3. Using the results of measurements on paragraph 5.5.2 GOST 20276-99, find the modulus of deformation of the soil.
2.3. Test ring stamp
2.3.1. Ring stamp 8 is connected with a rod 7, and it with the torque sensor 6, after which it is placed coaxially with the screw 4 under the thrust beam 2.
2.3.2. Using the methodology of ring cut GOST 20276-99 section 12.4, test method annular cut. Control and management of normal pressure automatically using a sensor 5 and the actuator 3. The measurement of the tangential load automatically using the torque sensor 6 and the load application manually using the handle 25. Measurement data are entered into the database of the computer.
2.3.3. Using the results of the measurements on the item 12.4.4 GOST 20276-99 find the strength characteristics of soils: the angle of internal friction and power unit clutch.
2.4. The test probe
2.4.1. Using the method of static sensing GOST 19912-2001 section 5 [C5], hold spymania using the proposed device. Speed continuous loading create servo 3 and control computer 20. Measuring the speed of immersion of the probe perform the motion sensor 22, and the signals from the sensors of the probe is passed through the control unit 18 in the base 20.
2.4.2. Using the measurement results in section 5.5 of the GOST 19912-2001, find the resistance of the soil to the introduction of the probe.
2.5. Tests to determine the elastic shear modulus
2.5.1. To determine the elastic shear modulus on the surface of the ground creating a shock, for example, a hammer weighing 8-12 kg on a metal plate 14, the resulting transverse wave recorded by the accelerometer 16.
2.5.2. Using the measured value of the propagation velocity of the shear wave (Vs)find the value of the elastic shear modulus:
where ρ is the density of the soil.
3. Tests impeller
Step 1. Prepare your device for testing.
1. The impeller 13 is connected with a rod 7, and it with the torque sensor 6. The force sensor 34 is connected to the control unit 18.
The impeller 13 is attached to the torque sensor.
Step 2. The sequence of testing
2.1. Using the technique of rotary cut GOST 20276-99 section 12.2, conduct testing of the impeller. The measurement of the tangential load automatically with use the of the torque sensor 6, and the load application manually using the handle 25.
2.2. Using the results of measurements on paragraph 12.2.4 GOST 20276-99, find the value of the specific clutch clay soils.
4. For sampling of soil using, for example, thin-walled sampler 15, which is set rod 7 is pushed continuously into the soil using a servo 3.
This device for complex determination of physical and mechanical properties of soils in the field of industrial realizable, has more features, enhanced accuracy of soil parameters.
1. Recommendations for the characterization of rheological properties of rock and soil half-rock method annular loading. L., VNIIG them. BE Vedeneeva, 1990, 4, 6, p.16-17.
2. USSR author's certificate No. 657315 A1, the application 2362128/25-28 from 17.05.1976, IPC5G01N 3/08, G01N 3/22, the applicant Moscow order of the red banner of Labor Institute of civil engineering them. V.V. Kuibyshev. The method of testing of soils, author V.L. Kubacki published 15.04.1979.
3. Handbook of engineering Geology, 3rd edition, revised and enlarged, edited by M.V. Churinova, M., Nedra, 1981, RES, str.
4. GOST 20276-99. The soils. Methods field determination of strength characteristics and deformable is on. M., 1999. - 91 S.
5. GOST 19912-2001. The soils. Methods field tests of static and dynamic probing. M., 2001. - 27 S.
1. Device for the comprehensive determination of physical and mechanical properties of soils in the field, containing the anchor, the thrust beam, the load screw, the rotary ring, the impeller and the cutter ring, characterized in that, to increase functionality and improve the measurement accuracy, it is provided with: a servo with a screw mounted on the thrust beam, a torque sensor mounted on the rod with a circular stamp, a force sensor, mounted in the lower part of the actuator, sensor, vertical displacement, mounted on the frame, the actuator, a force sensor, torque sensor, the sensor vertical displacement is connected to the unit control and interface to the computer, forming a measuring system with direct and inverse relationship between the sensors and servo.
2. Device for the comprehensive determination of physical and mechanical properties of soils in the field according to claim 1, characterized in that the torque sensor is a force sensor and the console.
3. Device for the comprehensive determination of physical and mechanical properties of soils in the field according to claim 1, characterized in that the anchor has embedded in it the three-coordinate the Axel is Romer and the power amplification and conversion of the signals into a digital form.
4. Device for the comprehensive determination of physical and mechanical properties of soils in the field according to claim 1, characterized in that the thrust beam is made foldable.
5. Device for the comprehensive determination of physical and mechanical properties of soils in the field according to claim 1, characterized in that the tests are performed automatically under computer control.
SUBSTANCE: method involves periodic determination of displacement of reference points located on the slope of mine rocks and earth surface adjacent to it, in vertical and inclined planes and buildup of full vectors of displacement of slope surface. Reference points are arranged in wells drilled in the mine rock massif slope, as per the displacement of which there calculated is a value of relative deformation of mine rocks in the near-slope zone for each well as per a mathematical formula. As per the line attaching the points to critical values of relative deformation there determined is a boundary of potential displacement surface of the near-slope zone rocks.
EFFECT: improving accurate determination of location of potential sliding surface and change of geomechanical state of mine rock massif in vicinity of that surface.
SUBSTANCE: method of dynamic probing of soils, in which a rod with a probe is submerged into soil by means of periodical shocks, and during each shock they determine parameters of soil impact to sensors of the measurement system, providing for amplification of signals from sensors, their analog-digital conversion, registration and transfer of data, including dependence of probe movement on time and dependence of head resistance variation on time, into the outer block of data processing with the help of the appropriate software, as a result of which they determine physical and mechanical characteristics of soil. The probe is submerged into soil with the help of a hydraulic hammer machine. The hydraulic hammer machine after introduction of the rod with the probe is lifted, and the rod is extracted with the probe after introduction of the probe to the specified depth by means of hydraulic hoists. In addition, to measure displacement of the probe during shock, they measure the outer sensor of movement with an autonomous recorder. Data registration is carried out with the help of a recording block adapted for direct connection with the outer block of data processing (computer). To determine soil characteristics, they perform mathematical modelling and solve an inverse problem based on experimental dependences of probe movement on time, variation of head resistance on time and other data.
EFFECT: increased manufacturability, efficiency and depth of research.
SUBSTANCE: set of devices for selection of vertical soil monoliths comprises a k number of thin-walled metal cylinders-monolith-selectors with tapered lower end of a triangular shape, equal to
EFFECT: improvement of accuracy of determining the properties of soil on genetic horizons of the soil profile, reduction of time for selection of the monolith and labour intensity of work in selection of the quality sample of the soil.
3 cl, 5 dwg, 1 tbl
SUBSTANCE: method to assess content of macrofragmental inclusions to characteristics of compressibility of mixtures of clayey soils includes sampling a soil mixture, definition of sample density and moisture, dry unit weight, separation of the sample into fine and coarse fractions, definition of content of fine Pf and coarse Pc fractions, and density of particles of fine
EFFECT: provision for determination of impact of macrofragmental inclusions content at characteristics of compressibility of clayey soil mixtures.
2 cl, 3 ex, 3 tbl, 3 dwg
SUBSTANCE: device to measure speed and direction of soil motion relative to an underground pipeline comprises a metering telescopic two-link lever with a sensor of elongation, a hinged joint, a unit of movements count. A hinged joint and a metering telescopic two-link lever are placed into a protective flexible case, besides, the metering sliding two-link lever in the case is fixed with the help of spring centralisers, and also in the metering telescopic two-link lever there is a unit of unlocking of a cord of elongation of the metering telescopic two-link lever.
EFFECT: provision of long-term fault-free operation of a device and convenience of its service without labour intensive earth works.
SUBSTANCE: method to determine frost heave of soil during freezing of a seasonally thawing layer includes drilling of a well before start of its thawing, sampling of soil, measurement of depth of seasonal thawing ξ, definition of dry soil density in samples ρd,th. In addition wells are drilled after freezing of the seasonally thawing layer, on the samples they additionally define density of dry soil after freezing of the seasonally thawing layer ρd,f, and the heave value is determined in accordance with the given dependence.
EFFECT: reduced labour intensiveness of works, increased accuracy of determination of heaving value, provision of material intensity reduction.
FIELD: measurement equipment.
SUBSTANCE: device for soil deformation measurement comprises a deformation-sensitive sensor optical cable, a measurement block connected with a cable, anchors connected to a cable and soil and is equipped with a system of cable protection against damage, including a safety fuse within each anchor, which actuates in case, when the force acting at the side of the anchor at the sensor cable exceeds the specified value.
EFFECT: provision of the possibility to limit a force transferred with an anchor to a sensor cable, in process of anchors displacement relative to each other, caused by soil movements, regardless of soil properties, which may be known unaccurately or change with time.
6 cl, 9 dwg
SUBSTANCE: sampler comprises a sampling bushing made with the possibility to increase its cross section in process of sample withdrawal, a facility for sampling bushing insertion into a tested material. The sampling bushing is made from two chutes, longitudinal edges of which are equipped with alternating rectangular ledges and grooves, at the same time location of ledge section in one chute corresponds to location of second chute grooves, besides, loops are formed from the ledges of the chute edges, longitudinal axes of holes of which are parallel to the longitudinal axis of the chute and coaxial to longitudinal axes of the second chute loops. Chutes are coupled with each other by means of longitudinal edges. Through holes of the loops at each longitudinal edge of the chute there is a rod pulled, one end of which is equipped with a head, the section of which is more than the section of the hole, and the second end of the rod is equipped with threading, is pulled through holes of the slab made as capable of fixation on the vibrator and is fixed with a nut, at the same time the free end of the sampling bushing is equipped with a circular pad from magnetic material.
EFFECT: provision of integrity of an initial structure of a material sample during its withdrawal from a tested massif of a placer mine, provision of the possibility for material sampling from depth that is more than 2-3 m.
4 cl, 2 dwg
SUBSTANCE: method is carried out by means of heading of containers, such as a cutting cylinder, onto a monolith. At the same time previously the soil is sampled. For this purpose a site is chosen, and in its centre a circular trench is dug with depth of not more than by 25 mm lower than the height of the cutting cylinder, belting the untouched soil, representing a truncated cone in shape, the diameter of the upper base of which is by 10…15 cm more than the inner diameter of the cutting cylinder, and the diameter of the lower base is more than the inner diameter of the cutting cylinder by 15…25 cm. From the soil left untouched the monolith is cut with the diameter of at least by 6 mm smaller than the inner diameter of the cutting cylinder and the height that is at least by 25 mm smaller than the cylinder height. At the same time the cylinder is periodically put on the monolith, using it as a template to monitor the diameter of the cut monolith. After cutting of the monolith and putting of the cutting cylinder on it, the cylinder is pushed into soil, until its upper layer levels with the monolith surface. In the space between the inner surface of the cutting cylinder and the outer surface of the monolith four Z-shaped supporting monolith-supporting plates are inserted with height equal to 3/4 of the cutting cylinder height. Evenly they are distributed along the cylinder perimetre and put on its upper edge. The slot between the inner surface of the cutting cylinder, the soil monolith and its supporting plates is filled with a molten waterproof material, having lower temperature of melting, for instance, a mineral wax. Afterwards the monolith is cut at the bottom at the lower edge of the cylinder, it is installed on the solid surface, packed and delivered to the area of filtration tests performance.
EFFECT: increased accuracy of soil filtration coefficient detection and accuracy of establishment of land reclamation system parameters, efficiency of using reclaimed soils, expanded zone of application of monoliths for detection of filtration coefficient.
SUBSTANCE: method for laboratory determination of rheological characteristics of soils includes detection of deformation characteristics of undisturbed or disturbed soil under conditions of uniaxial compression without possibility of its side expansion in a compression device in the mode of stresses relaxation, and a compression curve is built by final values of stresses and their appropriate deformations of the sample as each stage is completed. For each of relaxation branches they build curves of deformation dependence on deformation speed. Then points are market on these curves with selected values of sample deformation speeds, their appropriate values of deformations are applied onto relaxation branches, and a bundle of curves is pulled through them, as corresponding to selected values of deformation speeds. Using these curves, they determine values of deformations corresponding to the selected value of the vertical load, and on the basis of this data they build curves of deformation dependence on time, by which they determine coefficients of filtration and secondary consolidation with available methods.
EFFECT: reduced terms and labour inputs for performance of laboratory tests for determination of rheological characteristics of soils, including detection of coefficients of filtration and secondary consolidation.
5 cl, 6 dwg
FIELD: engineering investigations in building, particularly devices for determining deformation and strength properties of ground in well.
SUBSTANCE: device comprises probe (working tip), control-rod, pipeline, communication line, loading jig and measuring station. Probe includes hollow cylindrical body with bottom and cap filled with working liquid, elastic shell sealed from body bottom and top. Formed in non-fixed elastic shell area are perforations. Piston with rod is installed in upper part of hollow body above working liquid. Rod passes through cap in sealed manner. Rod is connected with control rod so that piston may move in axial direction. Formed above piston is cavity connected to pipeline. Hollow body has bottom in which air-tight plug is installed. Measuring device is made as linear piston displacement transducer. Through orifices are formed in hollow body wall near body bottom. Arranged from body outside are vertical or inclined grooves aligned with through orifices by lower ends thereof. Air-tight plug is provided with adjustable rest for restricting piston stroke.
EFFECT: simplified structure of probe and measuring devices, increased operational reliability and improved validity of obtained data.
2 cl, 1 dwg
FIELD: building, particularly building-and-engineering researches to investigate deformation ground properties.
SUBSTANCE: device has thrust structures including bearing plate connected with base by supports, mechanism for applying axial load to ground sample mounted on base and dynamo-metering structure. Dynamo-metering structure is made as frame formed by two longitudinal tie rods and two transversal beams. Cross-section of upper beam has the shape of horizontal H-bar along axis of plant symmetry. Strain gage transducers are arranged on working shoulders of H-bar, support part for sensing forces to be measured is connected to wall thereof.
EFFECT: increased measuring accuracy, reduced measuring time.
FIELD: mining industry.
SUBSTANCE: stand has device for pumping liquid and detachable shell, wherein model of filtering environment is placed. Detachable shell is connected to liquid forcing plant and has replaceable impenetrable elements for adjusting value of contact area of outer surface of filtering environment to liquid, made in form of inserts and ring isolators.
EFFECT: higher precision.
FIELD: construction, particularly engineering investigations to determine earth strength and deformation characteristics.
SUBSTANCE: method involves rotary driving hollow pipe string for the test depth with the use of boring rig so that minimal vertical load is applied to the pipe string. Pipe string is provided with screw punch blade having constant pitch and varying blade thickness which increases in down-top direction. Blade is provided with pressure transducers flushed with lower surface thereof. Pressure transducers are connected with original ground by communication cable. Module of deformation is determined with the use of well-known method by stabilized pressure value of each transducer after punch driving completion and from predetermined rate of deformation under each transducer. Rate between punch immersion depth per one turn h and pitch thereof a is synchronized up to obtaining value of h/a≤1.0 before reaching test depth for instance with the use of screw pair. Non-stabilized pressure values under each transducer are recorded immediately before punch driving stop.
EFFECT: increased measuring reliability and output.
5 cl, 1 dwg
FIELD: construction, particularly engineering investigations used in rapid building erection and reconstruction.
SUBSTANCE: method involves driving screw-in punch made as a blade in soil with the use of boring rig up to reaching soil test level simultaneously with driving screw-in anchor in soil, wherein screw-in punch and anchor are mounted on lower end of hollow pipe string so that they may perform limited movement one relative another and relative the pipe string with upper pipe string end secured to soil; applying predetermined load value to the punch; measuring punch immersion value at predetermined time intervals up to soil settlement stabilizing under the punch; applying next load value. Load application and measuring, as well as punch immersion method is performed in direct contact with punch of load applying device and linear displacement transducers with the use of feedback link connected with day ground. Load is applied to punch from day ground through technological hollow rod passing through pipe string hollow before test start. The rod is provided with load transducer cooperating with the punch and linear displacement transducers cooperating with the anchor. The anchor is used as reference point. Soil is tested in mode of set soil displacement under the punch by conditionally momentary deforming of soil under the punch in steps equal for soil to be tested. On reaching deformation step total load applied to punch and additional punch immersion are measured at predetermined time intervals. On reaching conditional load stabilizing on one step one will shift to the next step of soil deforming. Rate of change of specific pressure applied to soil with time is used as criterion of conventional load stabilizing on each step.
EFFECT: possibility to measure load applied to operating member and immersion thereof near soil test level, reduced test time.
5 cl, 4 dwg
FIELD: construction, namely engineering surveying to be carried out during building and building structure reconstruction, particularly accelerated surveying methods.
SUBSTANCE: device comprises hollow pipe string parts screwing up in ground with the use of boring rig. Pipe string parts are connected with each other by thread connections and additionally with pins. Screw impress with tail piece and screw marker with case are mounted on lower pin so that they may perform limited axial movement. Auxiliary rod is inserted in pipe string interior up to reaching impress tail piece. Lower end of auxiliary rod is provided with load sensor cooperating with marker case. Sensors communicate with day surface. Hydraulic power cylinder is installed between swivel head shaft and connected with upper end of auxiliary rod through centralizer having cut for cable passing. Each pipe string part additionally has inner left-handed thread formed in right-handed outer thread and annular inner seat located at lower end thereof. Hollow nipple is freely installed inside each pipe string part. Nipple has mating left-handed thread made on lower end thereof and mating outer annular seat located on upper nipple end. The annular nipple seat has socket, for instance adapted for socket wrench receiving to tighten pipe string parts by means of left-handed thread by unscrewing right-handed one during impress and marker removal. Marker case is provided with taper collet secured to lower end thereof so that taper collet surrounds impress tail piece by springing blades thereof. Packing gland in installed in taper collet interior. Screw impress is secured to tail piece by coaxial connector and shear ring having shear resistance less than that of other tail piece connections.
EFFECT: increased reliability during device driving in soil and drawing out from soil and increased accuracy of obtained information.
2 cl, 6 dwg
FIELD: construction technology; graphical methods.
SUBSTANCE: combined profiles of stresses are built at the plane of contact of rigid dye with flat-deformed base taking elastic state of base combined with plastic one taken into account. Law of shift of bounds of these states at area of contact is determined depending on raise in external average pressure (pav) while taking distribution of elastic contacts of stresses σzk e according to concave parabola law and distribution of contact stresses σz n of shift under smooth sole of stencil according to straight line rule. The straight line crosses concave parabola of elastic stresses at the bound of area of elastic and shift deformations. Parameters of carrying ability of base depending on internal friction angle φ, engagement c and volumetric weight γ are calculated for stencils of known shape, sizes, rigidity and degree of roughness of its sole. Contact tresses are determined from coordinates of profiles. Profiles after being built are represented as mirror reflection relatively axis of ordinates and profiles of elastic and shift contact stresses are got under surface of stencil.
EFFECT: solution of combined elastic-plastic contact problem.
FIELD: investigating or analyzing materials.
SUBSTANCE: method comprises plane-parallel deforming of soil base by external pressure and determining the specific bond and angle of internal friction of the soil base.
EFFECT: enhanced precision.
FIELD: construction engineering.
SUBSTANCE: method concludes in determining parameters of physical and mechanical characteristics: internal friction angle φ, specific adhesion c and volumetric weight of depth-uniform ground base and anisotropic turf deposit γ. Value of average external pressure ρave applied to base through flat hard template of average size is calculated, which average pressure corresponds to moment of phase shift of base from one state to the other to determine specific processes of sharp growth of deposits, reduction in strength and possible loss of stability in total and to determine carrying capacity of flat-deformed base when pattern of operation of ground base is seen as linearly deformed space and turf deposit - as Fuss-Winkler model of local elastic deformations. In this case new phase conditions of ground are found and phase states under turf deposit load are determined depending on sizes and shapes of hard flat templates.
EFFECT: improved precision of calculation.
FIELD: investigation of foundation soil in situ, particularly to construct and reconstruct existent buildings and building structures.
SUBSTANCE: method involves monoaxial ground sample compression in compression apparatus along with prevention of radial expansion thereof, wherein the ground sample is tested in stress release regime; plotting compression curve after each stage termination by final stress values and corresponding sample deformations. As predetermined sample deformation value is achieved additional ground sample settlement is restricted by partial stress release to approximate value thereof to conditional stress stabilization or sample deformation value.
EFFECT: reduced ground investigation time.