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3171results about "In situ soil foundation" patented technology

Portable on-spot and indoor dual-purpose direct-cutting experiment instrument and its sampling method

A direct shear tester for both portable field test and indoor test and a sampling and testing method are provided. The tester comprises a sampling device, a portable vertical load system and a horizontal shear system. The testing method comprises burying a rigid frame together with a cruciform shear frame in the soil of a place to be test, digging out the whole soil containing the rigid frame and the cruciform shear frame to obtain an integrated sample with less interference, placing and fixing the integrated sample in a rigid frame base on a box-shaped frame, applying a vertical force by using the portable vertical load system on the box-shaped frame, and measuring the strength of the sample by using the shear frame. During the test process, the volume change of the sample in the vertical direction is not limited. The tester has simple structure, easy operation and good portability. The testing method employs flexible tension shear mode instead of the rigid top-bunt shear mode, overcomes the friction and sampling problems, and avoids the vertical pressure offset during the test process by using the portable vertical loading system, thereby increasing the test accuracy.
Owner:HOHAI UNIV

Soil compaction measurement

An apparatus and method are provided for the in-situ measurement of the stiffness of a layer of soil or other surface of interest. The apparatus includes a contact foot for engaging the surface and a drive transducer coupled to the contact foot for applying a vibratory force to the contact foot in response to a drive signal. A motion sensor is coupled to the contact foot and in a preferred embodiment an additional sensor measures the force applied to the contact foot and hence to the surface. These sensors generate corresponding output signals. The output signals are used to generate a measurement signal that is representative of the surface stiffness.
Owner:RAYTHEON BBN TECH CORP

Measurement device incorporating a locating device and a portable handheld computer device and associated apparatus, system and method

A system adapted to determine a property of a paving-related material is provided. Such a system comprises a central computing system housing database, such as a geographic information system (GIS). A measuring device for selectively and directly measuring the property of the paving-related material is remotely disposed with respect to the central computing system and operably engaged with a locating device, such as a global positioning system (GPS) device, for determining a location of the measuring device when the property of the paving-related material is selectively measured thereby. A portable handheld computer device is in communication with the measuring device, the locating device, and the central computing system, wherein the handheld computer device is configured to receive data, comprising the measured property of the paving-related material and the corresponding location of the measuring device when the property is selectively measured thereby, from the measuring device and the locating device, and to communicate the data with the central computing system for incorporation of the data into the database. An associated device, apparatus, and method are also provided.
Owner:TROXLER ELECTRONICS LAB INC

Integrated porous rigid wall and flexible wall permeability test device for soils

An apparatus for measuring permeability accurately in expansive clay and non-expansive soils is provided. The apparatus includes hollow porous stone cylinders which prevent the sample from bulging and at the same time allow application of confining pressure on the soil sample enclosed in a flexible membrane, which simulates the field condition and allows for application of back pressure to aid in saturation. The apparatus also allows for accurate comparison of hydraulic characteristics of swelling clays with fluids of various dielectric and other properties. The apparatus can also be used to consolidate the sample either three dimensionally or in one direction and perform permeability tests as well as find out the consolidation characteristics of the sample.
Owner:NORTH DAKOTA STATE UNIV RES FOUND

Method and apparatus for generating acoustic signals for LWD shear velocity measurement

An acoustic logging apparatus comprises a drill collar conveyed on a drilling tubular in a borehole within a formation. At least one transmitter is disposed in the drill collar. The transmitter includes at least one magnetostrictive actuator cooperatively coupled by a flexure ring to a piston for converting a magnetostrictive actuator displacement into a related piston displacement for transmitting an acoustic signal in the formation.
Owner:BAKER HUGHES INC

Continuously threaded hold-down system

A hold-down system used to secure a building structure to the foundation, thereby enabling the building to better withstand forces like high winds and earthquakes because these forces may then be distributed to the foundation. The hold-down system is characterized as being continuously threaded and having stackable, individual take-up units. A continuously threaded hold-down system allows the system to compensate for shrinkage or crushing of the building's frame throughout each level of the building because the anchor of the system is always in communication with the foundation of the building. The individual take-up units are stackable allowing each level of the system to compensate for shrinkage or crushing on that level as well as adjacent levels.
Owner:COMMINS ALFRED D

Monitoring method of bottom soil heave of excavation foundation pit

ActiveCN103352455AReal-time monitoring of uplift deformationArbitrarily adjust the height required for measurementIn situ soil foundationDeformation monitoringEngineering
The invention belongs to the technical field of foundation pit deformation monitoring and particularly relates to a monitoring method of a bottom soil heave of an excavation foundation pit. The monitoring method comprises the specific steps of: arranging a prism hoisting device on a monitoring point at the bottom of an excavated foundation pit and fixing a prism at the top; erecting a total station for forming intervisibility with the prism on the ground outside the foundation pit so as to realize the aim of monitoring the deformation amount of the bottom soil heave of the foundation pit; meanwhile, selecting a standard point on a stable building outside the foundation pit and setting the prism so as to monitor a micro deformation amount of a work station and revise a measured value of the monitoring point according to the micro deformation amount, thus improving the measuring precision. The monitoring method disclosed by the invention has the advantages that the deformation amount of the bottom soil heave of the foundation pit is monitored in real time; the operation method is simple and convenient; a monitoring device is existing equipment, the cost is low and the measurement precision is high; the prism hoisting device can randomly adjust and measure the needed height so that the intervisibility is formed by the prism and the total station all the time; the monitoring method is particularly suitable for foundation pit engineering in an excavation process.
Owner:SHANGHAI URBAN CONSTRUCTION MUNICIPAL ENGINEERING (GROUP) CO LTD

Apparatuses for interaction with a subterranean formation, and methods of use thereof

An access casing assembly structured for placement at least partially within a subterranean formation by forcing the access casing assembly thereinto, comprising a plurality of casing sections operably coupled to form a central elongated cavity for providing access to the subterranean region is disclosed. Further, a tip portion of the access casing assembly may include a porous filter through which liquid or gas may communicate with the central elongated cavity. Also, a receiving member or at least one engagement hub may form a portion of the central elongated cavity and may include an engagement feature configured for selectively and lockingly engaging a locking structure of a device to be positioned within the access casing assembly. Methods of use are disclosed. A tensiometer is disclosed including a chamber structured for allowing at least partially filling with a fluid subsequent to contact therewith.
Owner:BATTELLE ENERGY ALLIANCE LLC

Test Device for Determining Three-Dimensional Consolidation Properties of Soils

Standard test methods for determining one-dimensional consolidation properties of soils using incremental loading in accordance with ASTM D2435, or AASHTO 216, and of those of other international and organizations, do not accurately predict the values of vertical settlement, coefficients of consolidation in horizontal and vertical directions, and modulus of elasticity in vertical direction, because fixed ring used in these tests do not allow horizontal settlement and dissipation of excess pore-water pressures in horizontal direction, whereas, in field, under application of a vertical load, both horizontal and vertical settlements occur along with dissipation of excess pore-water pressures in both vertical and horizontal directions. To overcome this more than 100 year old problem, the inventor (Dr. Ramesh Chandra Gupta, Ph. D., P.E.) has invented a test device for determining three-dimensional consolidation properties of soils, using a flexible ring which permits development of horizontal and vertical displacements, and dissipation of excess pore-water pressures in both horizontal and vertical directions, along with increased lateral resistance as takes place in field at any depth in a soil deposit when vertical load at the surface is applied.The flexible ring consists of filter fabric around the soil specimen, rubber membrane around the filter fabric, circular segmental metal plates around the membrane and elastomeric rubber bands or spring loaded jacket around the segmental plates, and allows horizontal and vertical displacements, dissipation of pore-water pressures in horizontal and vertical directions to take place with increased lateral resistance with each increment of vertical load like those in the field. Thus new test device simulates field condition to allow accurate determination of three-dimensional consolidation properties of soils (such as settlements, coefficients of consolidation in horizontal and vertical directions, and modulus of elasticity).For this new test device, conventional incremental consolidation frame or triaxial type chamber system either with the triaxial loading system or modified to adapt to incremental consolidation frame, shall be used to perform three-dimensional consolidation tests.
Owner:GUPTA RAMESH CHANDRA

Device and method for measuring soil body displacement

ActiveCN102518110ARealize automatic intelligent measurementAccurate continuous responseIn situ soil foundationRelative displacementMeasurement device
The invention relates to a device and a method for measuring soil body displacement. The device comprises a sedimentation pipe or an inclinometer pipe, a magnet ring locating sensor and a data acquisition device. The sedimentation pipe or the inclinometer pipe is embedded in the soil body. The magnet ring locating sensor is parallelly arranged inside the sedimentation pipe or the inclinometer pipe and covers displacement changing range of a magnet ring in the whole journey, serves as a measuring basis, is constant in fixed position and comprises a plurality of magnetic sensitive elements, a strip-shaped support piece and a detection circuit. The device and the method can achieve automatic intelligent measurement of soil body displacement, are suitable for measurement of relative displacement of the soil body in one direction, and have the advantages of being simple in use and good in measuring reliability.
Owner:CHINA GEOKON INSTR

Method and apparatus for raising, leveling, and supporting displaced foundation allowing for readjustment after installation

A method and apparatus for raising, leveling, and supporting a foundation by placing steel piers beneath the necessary peripheral and interior beams and using a jack to raise the slab beams, then allowing the slab beams to rest on piers. The piers are constructed from steel piling segments, driven into the ground, connected with adhesive, and anchored at a depth offering reactive force sufficient to support the foundation. The piling is pointed at its bottom facilitating insertion and preventing upheaval. A crown is attached to the upper most end of each pier which offers a platform to provide a stable support once the jack is removed and easy access to the slab beam for later readjustment. Multiple piers are utilized to achieve a level foundation. Piers may be placed beneath interior beams on a slab without drilling holes in the interior of the slab.
Owner:MITCHELL LEROY

Mobile turf instrument apparatus having driven, periodically insertable, ground penetrating probe assembly

A mobile turf instrument apparatus has a wheeled frame that may be propelled over the ground by a motive device, such as by a separate vehicle or by its own engine and drive train. A driven arm is carried on the frame and revolves in circles to periodically insert the probe(s) of a probe assembly into the ground during motion of the frame. The drive to the arm is momentarily disengaged when the probe(s) of the probe assembly are inserted into the ground. The probe assembly comprises two parts that rock relative to one another. Two soil measurement devices are connected to the probe assembly. A soil moisture sensor is coupled to the probe assembly for measuring soil moisture when the probe(s) are inserted into the ground. A load cell is responsive to the amount of rocking of the two parts of the probe assembly to measure soil compaction.
Owner:TORO CO THE

Technology for performing foundation pile quality detection and geology survey by adopting single tube longitudinal wave method

InactiveCN103255785AAchieve non-destructive quality inspectionImprove accuracyFoundation testingIn situ soil foundationCombined testTesting equipment
The invention relates to a technology for performing foundation pile quality detection and geology survey by adopting a single tube longitudinal wave method. The technology is relevant to comprehensive testing of the actual using effect of a foundation pile and is characterized in that longitudinal wave transmitting downwards along a pile body is generated by knocking the top surface of the foundation pile, the longitudinal wave velocity and pile length of the foundation pile can be accurately measured by detecting the time difference of arrival of the longitudinal wave in a sounding pipe, and the quality of pile body concrete can be judged; actual measurement on the time difference of arrival of the longitudinal wave which is transmitted from the pile side soil along the knocked pile body can be conducted in adjacent pipelines or geological bore holes, and the length of the foundation pile, the pile body quality and the chambering degree can be measured; and the wave length of a geological soil layer can be measured, the condition of the geological soil layer around the pile can be judged, and the rock-inlet condition of the foundation pile can be analyzed. By means of the technology for performing foundation pile quality detection and geology survey by adopting the single tube longitudinal wave method, a signal processor can be configured externally or inserted in on the basis of the existing low-strain ultrasonic detection devices and the like, the technology can achieve foundation pile quality nondestructive testing and geology survey, is an economic and ready-made pile foundation nondestructive testing auxiliary validation method and can remarkably improve accuracy and service level of pile foundation quality decision.
Owner:陈彦平

Worksite preparation method using compaction response and mapping information

A worksite preparation method includes moving a compactor machine across at least one region of a worksite, and sensing values indicative of a compaction response of work material in a compacted region. The method also includes generating a machine traffic plan in real time responsive to the sensed values, outputting control signals corresponding to the machine traffic plan and taking a worksite fill action responsive to the control signals.
Owner:CATERPILLAR INC

Embedding apparatus and method for earth pressure box

InactiveCN101487249AReliable risk assessmentScience of control measuresIn situ soil foundationPressure cellSubway station
The invention discloses a device and a method for burying a soil pressure cell, relating to the soil pressure cell application technique when monitoring the soil pressure during the risk evaluation and control in civil engineering. The device consists of a base and a sliding pushing guideway; the base can freely slide on the siding pushing guideway; the base comprises a soil pressure cell bottom shoe (2), a guideway wheel (3), a lead pipe trough (4) and a connecting batten plate (5); the sliding pushing guideway comprises a U-shaped guide sliding trough (6), a connecting steel plate (7), a position limit plate (8), a steering shaft (9), a steering steel wire (10), a rigid connecting plate (11) and an L-shaped screw (12). The device and the method for burying a soil pressure cell can be widely applied to the burying which is in the risky evaluation of deep pit construction of urban subway station or high-rise building and during monitoring and measuring the soil pressure; the survival rate of the soil pressure cell is high, the burying depth is not restricted, the positioning is exact, the installation cost is low, the data is true and exact and the regularity and pertinence are good.
Owner:INST OF ROCK & SOIL MECHANICS CHINESE ACAD OF SCI

Soil and stone mixed filling roadbed compaction degree detecting method

The invention discloses a soil and stone mixed filling roadbed compaction degree detecting method, which comprises the steps of: randomly selecting a soil and stone mixed filling roadbed test site, and obtaining the site compaction degree by a single-point douche or a sand cone method; carrying out fast static test in a preset position near the test site and obtaining a curve between the penetration power P and the penetration depth w; calculating the average density Rhom of the soil and stone mixed filling roadbed and calculating the initial void ratio n0 in the preset position; carrying out linear fitting according to the curve between the penetration power P and the penetration depth w and obtaining the value of the initial intermediate quantity a0 and b0; calculating the void-free deformation modulus E0 of stone particles of the soil and stone mixed filling roadbed; and calculating the compaction degree of other positions, i.e. the compaction degree in the ordinary positions. The method can be used for fast, stably and accurately detecting the compaction degree of the soil and stone mixed filling roadbed and is suitable for any compaction process and roadbeds compacted by compaction machinery.
Owner:HUNAN UNIV

Foam pile system

In this invention, after a hole has been drilled or excavated, injection probe(s) are placed at appropriate depth(s), the excavated native materials are replaced with appropriately sized crushed rock or other natural or synthetic materials, and then a polymeric resin is injected through the probe(s) to encapsulate and bind the fill material, whereby upon curing the polymeric resin and fill material forms a foam friction pile. Such friction piles drilled or excavated adjacent to each other will form a foam sheet piling system. The foam piles can also be re-enforced using nylon, polypropylene, fiberglass, other synthetic or non-synthetic materials or combinations of these materials. The polymeric resin typically would comprise a high density closed cell, water resistant expanding two component polyurethane foam system.
Owner:POLY-MOR CANADA INC

Measurement method of karst cave type foundation collapse risks

The invention relates to a karst cave type foundation stability estimation method, in particular to a measurement method of karst cave type foundation collapse risks. The measurement method mainly solves the problem that because comprehensive prediction methods for the karst cave type foundation stability are immature in the prior art and judgment models are established on the basis of different angles, the reliability of influence factors is greatly lowered. According to the specific scheme, the relation between vertical stress of overlaying soil on karst caves and limit vertical stress of the overlaying soil on the karst caves is derived and established according to the karst collapse mechanism of karst cave type foundations, stability loss risk estimation parameters for determining karst cave type foundation collapse are proposed, and the one-to-one corresponding relation between the karst cave type foundation stability loss risk estimation parameters and stability factors is established. The measurement method has the advantages of having clear stability criteria, being simple and practical and having high practicality value for effective prediction, prevention and control of karst cave type foundation collapse.
Owner:QINGDAO TECHNOLOGICAL UNIVERSITY

Test Device For Determining Three-Dimensional Consolidation Properties Of Soils

Standard test methods using a fixed ring for determining one-dimensional consolidation properties of soils represent a subsurface condition where settlement and dissipation of excess pore pressure is possible only in vertical direction. This subsurface condition never occurs, as settlements and dissipation of excess pore pressures always occur in horizontal and vertical directions. Dr. Ramesh Gupta has invented a test device for determining three-dimensional consolidation properties of soils, using a flexible ring permitting displacements and dissipation of excess pore pressures in both horizontal and vertical directions, and affording determination of coefficients of consolidation in horizontal and vertical directions including three-dimensional coefficient of consolidation, and modulus of elasticity. The test device consists of a flexible ring consisting of filter fabric around the soil specimen, rubber membrane around the filter, circular segmented metal plates around the membrane and rubber bands or rings around the plates. Both incremental or triaxial type loading can be used with this device.
Owner:GUPTA RAMESH CHANDRA

Wireless rotating penetrometer

The present invention discloses a wireless rotating penetrometer. The penetrometer organically integrates drilling and penetration and realizes wireless transmission with electromagnetic waves. The penetrometer can acquire penetration parameters in real time, overcome certain defects of traditional static penetrometers, and quickly, accurately and conveniently realize the in-situ tests of stratum depth. Stratum probing depth can be obviously increased, the defects resulting from the use of cables in signal transmission, such as easy joint damage, poor insulation, long time consumption for operation, etc can be overcome, investigation depth and quality can be largely improved, and investigation cost can be reduced. The penetrometer can be broadly used in the investigation of expressways, railways and other important buildings.
Owner:CHINA UNIV OF GEOSCIENCES (WUHAN)

Filing layered sedimentation monitoring device and method

The invention discloses a filing layered sedimentation monitoring device and method. The monitoring device comprises a bottom sedimentation monitoring unit, a middle sedimentation monitoring unit and a ground surface sedimentation monitoring unit which are buried in a soil layer to be monitored from bottom to top and are vertically arranged. Burying holes are formed in the soil layer to be monitored. An anchoring head is arranged under the bottom sedimentation monitoring unit. The bottom sedimentation monitoring unit, the middle sedimentation monitoring unit and the ground surface sedimentation monitoring unit are all provided with inclinometer pipes, extensible pipes arranged on the outer sides of the inclinometer pipes in a sleeving mode and displacement sensors installed on the upper portions of the inner sides of the inclinometer pipes. The monitoring method comprises the steps that firstly, drilling of the burying holes is conducted; secondly, the bottom sedimentation monitoring unit is installed; thirdly, the middle sedimentation monitoring unit is installed; fourthly, the ground surface sedimentation monitoring unit is installed; and fifthly, layered sedimentation monitoring is conducted. The filing layered sedimentation monitoring device and method are reasonable in design, convenient and easy to operate, convenient to bury, high in measuring precision and capable of effectively solving the problems that existing layered sedimentation monitoring equipment is large in equipment burying workload and low in measuring precision.
Owner:CHINA JK INST OF ENG INVESTIGATION & DESIGN

Reinforcement method and reinforcement structure for treating railway soft soil roadbed settlement overweight before operation

ActiveCN102926304AReduce damageThe construction period of the main structure is shortRoadwaysFoundation testingOverweightObservation system
The invention discloses a reinforcement method and a reinforcement structure for treating railway soft soil roadbed settlement overweight before operation. The reinforcement structure mainly consists of five parts, namely a main bearing structure system, a reinforced cushion layer structure system, a foundation bed drainage system, a settlement observation system and a reserved grouting system. The technical problems that the existing roadbed is greatly damaged, the construction period is long, the construction property is low, the quality is difficult to control and the problem that the soft soil roadbed settlement overweight is caused in the conventional technical scheme are effectively solved.
Owner:CHINA RAILWAY SIYUAN SURVEY & DESIGN GRP

Lower-bound limit analysis method of ultimate bearing capacity of jointed rock slope considering rock translation and rotation effects at the same time

ActiveCN107330145AIntuitive form of destructionSimple optimization solutionClimate change adaptationDesign optimisation/simulationSlope stability analysisIterative method
The invention relates to a lower-bound limit analysis method of bearing capacity considering rock translation and rotation effects at the same time, and belongs to the technical field of rock slope stability analysis. According to the method, a rigid block unit is scattered as a geometry system of a rigid rock and a structural plane, the normal force, shearing force and bending moment of the structural plane are used as unknown quantities, a static permission stress field satisfying an equilibrium equation considering the translation and rotation effects of the rigid block unit, structural plane shear yield conditions, structural plane tensile yield conditions, structural plane rotational yield conditions and static boundary conditions is constructed, an overload coefficient is used as a target function, and a lower-bound linear mathematic programming model is built; the linear mathematic programming model is solved by means of an interior point algorithm, a strength reserve coefficient is solved by means of an iterative method at the same time, and the lower-bound solution and corresponding yield area of the overload coefficient or the strength reserve coefficient of the jointed rock slope are acquired. The method has the advantages that the concept is clear and the computational accuracy is high, and the method can be applicable to bearing capacity analysis of translational or rotational failure of the jointed rock slope.
Owner:KUNMING UNIV OF SCI & TECH

A construction method of collapsible loess foundation

The invention discloses a construction method for a collapsible loess foundation. The construction method comprises the following steps of: firstly, performing foundation treatment on a loess field with collapsibility by using a super downhole dynamic consolidation (SDDC) pile; secondly, collecting undisturbed soil on site, normally performing an indoor experiment to measure an inter-pile soil compaction coefficient and an SDDC pile body compaction coefficient, evaluating the collapsibility, and if any one of the three indexes cannot meet a design requirement, performing pile compensation construction on the SDDC pile until the design requirement is met; and finally, pouring the pile and mudjacking. The method has the advantages of economy, environment friendliness, high treatment depth, good treatment effect, large bearing potential, high complicated load resistance and the like. By application of the method, various side effects caused by the collapsibility of the deep collapsible loess field can be eliminated, and requirements of upper-part high rise buildings on the bearing capability and settlement of the foundation can be met.
Owner:XI'AN UNIVERSITY OF ARCHITECTURE AND TECHNOLOGY

Online evaluation method for compaction quality of earth and rockfill dam material

The invention provides an online evaluation method for compaction quality of an earth and rockfill dam material and provides an online evaluation method for compaction quality of a dam material, which is suitable for monitoring rolling parameters and compaction effect in real time and taking dam material property into consideration. The compaction quality of the earth and rockfill dam material is comprehensively evaluated in real time; and a technical scheme adopted in the method is that the online evaluation method for the compaction quality of the earth and rockfill dam material comprises the following steps: collecting field test pit experiment results by using a PDA (Personal Digital Assistant); establishing a compaction quality evaluation model; figuring out the compact quality of each grid of the current construction bin surface; next, obtaining the compaction quality in any position of the current full construction bin surface by using a spatial interpolation method; furthermore, analyzing a quality qualified or disqualified area according to a compaction quality control principle, figuring out qualified rate of the compaction quality of the current construction bin surface; and feeding back the qualified rate in time to instruct field construction so as to control construction quality. The online evaluation method for the compaction quality of the earth and rockfill dam material, provided by the invention, is mainly applied to online evaluation of the compaction quality of the earth and rockfill dam material.
Owner:TIANJIN UNIV

Seabed static sounding penetration device

The invention provides a seabed static sounding penetration device which comprises a base frame for supporting the whole device, a probe storage, a traveling mechanism, a manipulator, a ground anchor, a bottom plate, a rotating intermittent mechanism and a hydraulic power source. The bottom plate is fixedly connected to the bottom of the base frame. The probe storage at least comprises a storage frame, a probe, a probe frame and a rotating shaft. The storage frame is fixed on the bottom plate. The rotating shaft and the probe frame are positioned in the storage frame. The probe is placed on the probe frame. The rotating shaft is fixed at the center of the probe frame and can drive the probe frame to rotate, wherein the top end of the rotating shaft is fixed at the top of the storage frame through a rolling bearing; and the bottom end of the rotating shaft is fixed on the bottom plate through a rolling bearing. The seabed static sounding penetration device has compact structure, is simple and convenient to control, is reliable and stable to use, can be used for realizing a sounding process with the maximum cone penetration depth of 15m, is suitable for the seabed static sounding and can also operate on the land.
Owner:CHINA UNIV OF GEOSCIENCES (WUHAN)
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