620 results about "Frost heaving" patented technology

The present invention relates to a model test device, and specifically to a frozen soil mechanics model test device. The invention is characterized in that the frozen soil mechanics model test device has a full-steel box type structure which comprises a heat insulation box body, a baseboard temperature controller, a water supplying device, a loading device and a data collecting and processing device. The device adopts a welding mode for connecting to a whole, and only one side plate adopts bolt connection, wherein, the baseboard structure of heat insulation box body comprises a heat insulationbaseboard, a water supplying pool and a top plate of water supplying pool. The structure gives attention to the functions of water supplying and temperature control. The water supplying device comprises a water level controller, the water supplying pool and a water supplying pipeline device. The charging device comprises a hydraulic jack and a hydraulic oil pump. The data collecting and processing device comprises a DT500/600 series data collector, a XSL series temperature measuring instrument and various types of sensors. The device of the invention has the advantages of realizing unidirectional and bidirectional freezing condition, realizing the water supplying of water migration in freezing process, providing the load of model test load application damage, monitoring the temperature field and stress field of frozen soil, monitoring the frost heaving, subgrade settlement deformation, etc.; and realizing the automatic collection and analysis of test data in the test process.

The present invention provides a freeze-thawing circulation detection apparatus for nature saline soil, wherein the apparatus is used for detecting the formation process of saline soil under nature environment conditions and detecting the frost heaving and melt sinking change law of the saline soil during multiple freeze-thawing circulation processes. According to the present invention, the upper portion of a sample tube of the apparatus is connected with a low temperature constant temperature box for detecting the temperature change under a nature state, temperature setting is decided according to the air temperature of a region, the bottom of the sample tube is fixed with a temperature control head, the detected temperature between the soil under the nature conditions is set as +5 DEG C, and the temperature control head on the bottom is connected with a water replenishment device for detecting groundwater and salinity replenishment under the nature conditions; and with the freeze-thawing circulation detection apparatus for nature saline soil, the freeze-thawing circulation mechanism of the saline soil can be well reflected so as to provide reference for engineering construction in the saline oil area.

The invention discloses a frost heaving meter. The frost heaving meter comprises a supporting part, a temperature control part, a geotechnical testing part and a data acquisition part, wherein the supporting part comprises a bottom plate, two guide columns fixed on the bottom plate, a connection plate arranged at the upper parts of the guide columns, and limiting parts arranged on the connection parts; the geotechnical testing part comprises a soil sample device and a weight loading device; the temperature control part comprises a temperature control system which is connected with an upper temperature disc and a lower temperature disc respectively; the data acquisition part comprises a temperature probe and a moisture content probe which are arranged on a glass test sample barrel, a pressure sensor arranged between the upper temperature disc and a movable plate, and a displacement sensor arranged between the weight loading device and the supporting part. The frost heaving meter has the advantages of multiple functions, high precision, wide applicability, convenience in utilization and the like.

Construction features of roadbed are as follows: building vent-pipes perpendicular to direction of roadbed in certain depth of road embankment; installing ventilating units of automatic controlling temperature at end part of vent-pipe; setting up thermal-protection material between vent-pipes/entire up part of vent-pipes with earth material being covered and tamped. The said automatic controlling ventilating units carries out heat exchange between inside roadbed and airflow in low temperature outside. The thermal-protection material protects ever frost effectively. Thus, the invention prevents frost heave and thaw collapse caused by season change so as to keep stability of roadbed in high level. The invention solves issue of carrying construction in zone of frozen earth.

The invention discloses a vertical cup type freezing reinforcement structure and method at the shield tunnel end. The vertical cup type freezing reinforcement structure is multiple rows of vertical freezing pipes which are distributed in a soil body outside a working well at the shield tunnel end and are distributed to be shaped like a Chinese character 'kou', horizontal freezing pipes are arranged on the lower portion of the soil body on which the vertical freezing pipes are distributed in the working well at the end, refrigerant media are circulated in the vertical freezing pipes and the horizontal freezing pipes, and therefore a vertical cup type frozen wall reinforcement body can be formed in the soil body outside the working well at the shield tunnel end. The reinforcement method comprises the steps of step 1, freezing designing; step 2, refrigerating system designing; step 3, drilling constructing; step 4, freezing constructing; step 5, slot wall breaking; step 6, freezing pipe removing; step 7, frost heave and thaw subsidence controlling. The vertical cup type freezing reinforcement structure and method at the shield tunnel end has the advantages that a strata reinforcement mode for the end of a soft soil area which is rich in a water sand layer is achieved, the problem that in the area, a conventional reinforcement mode is poor in reinforcement effect can be effectively solved, and it can be guaranteed that a shield tunneling machine smoothly breaks in and out a tunnel portal.

The invention relates to a three-dimensional-drainage roadbed structure for preventing water damage of a road in a cold region. The structure is characterized in that a three-dimensional drainage system consisting of horizontal drainage layers, vertical drainage passages and a slope drainage layer is arranged inside a road embankment; the horizontal drainage layers comprise at least two horizontal reinforced drainage layers; the vertical drainage passages are arranged between the topmost reinforced drainage layer and the bottommost reinforced drainage layer; a roadbed slope is laid with a drainage plate and a geotechnical waterproof material layer; a longitudinal and transverse drainage pipe network is arranged inside the bottom reinforced drainage layer; each middle reinforced drainage layer is provided with an air duct; a geotechnical waterproof material layer and a geotechnical reinforced material layer are laid on the top and at the bottom of each reinforced drainage layer respectively. Through reasonable arrangement of a three-dimensional drainage and waterproof structure in a roadbed, water can be quickly removed from the roadbed from multiple layers, thus helping to protect a road surface from frost heaving, thaw collapse, frothing and other problems. The invention further discloses a construction method of the three-dimensional-drainage roadbed structure for preventing the water damage of the road in the cold region.

The invention provides a full-sectional grouting, rectangular horizontal freezing and pipe roof combined reinforcing structure and a full-sectional grouting, rectangular horizontal freezing and pipe roof combined reinforcing method. The structure comprises a rectangular freezing wall, a freezing hole 1, a temperature measuring hole 2, a pressure relief hole 3, a pipe roof 4, a full-sectional grouting region 5, an underground passage initial lining structure 6 and an underground passage second lining structure 7. The structure and the method provided by the invention have the beneficial effects that the structure and the method are suitable for water-rich sandy soil layer or soft soil layer rectangular underground passage underground excavation reinforcing engineering with open excavation construction incapability during the construction of important under-passing buildings in an urban center; the intensity and the watertightness of a reinforcing body are ensured through combining a rectangular horizontal freezing wall in the reinforcement; the stability of an excavation tunnel face is ensured through the grouting reinforcement, meanwhile, the frost heave and thawing subsidence phenomenon caused by freezing is inhibited; the protection effect on sensitive environment is ensured; the influence of upper part thin overburden digging unloading on the important buildings is controlled by the pipe roof; the existing freezing hole, grouting and pipe roof construction machinery does not need to be subjected to technical improvement; and the construction is convenient. Compared with other chemical reinforcing methods, the method provided by the invention has the advantages that the safety is high; the environment is protected; and the benefits are obvious.

The present invention discloses a frost heave force model of a rock tunnel based on a rock-water-ice force in-situ test. A pore water pressure gauge, an earth pressure box, and a multi-point platinumresistance temperature sensor are used in a combination manner to perform a frost heave force in-situ test on fractured rocks, the temporal and spatial evolution laws of the fissure water pressure, the ice pressure, and the surrounding rock pressure before and after freezing of the fractured rocks are obtained, and theoretical model calculation results, in-situ test results, and existing researchresults are compared and analyzed. According to the frost heave force model of the rock tunnel based on the rock-water-ice force in-situ test provided by the present invention, in-situ testing on siteis used, the test method is innovated outside the previous test system mainly containing the freeze-thaw cycle mechanics test of fractured rock masses, the lack of measurement methods is compensated,the frost heave force in natural water-containing cracks is obtained, and starting from macro and engineering applications, the discussion of the meso-structure and fracture geometry of fractured rocks is avoided; the general area of low-temperature water-ice phase transition and the direction of water migration are considered; and the frost heave force model of the rock tunnel based on the rock-water-ice force in-situ test provided by the present invention will provide a reference for similar projects of the currently developed Sichuan-Tibet Highway.

The invention discloses a double-chamber determinator for the volume frost-heaving ratio of frozen soil. The determinator comprises a heat-preserving chamber, a sample pipe, a heat-insulating seat, a sample container, a differential pressure transducer and a cold bath, wherein the sample pipe is provided with a water inlet pipe and is arranged in the heat-preserving chamber, the bottom pipe orifice of the sample pipe is hermetically connected with the heat-insulating seat, the sample container is arranged in the sample pipe and on the heat-insulating seat, one end of the differential pressure transducer is communicated with the sample pipe through a water guiding pipe, the other end of the differential pressure transducer is connected with a reference water pipe, the cold bath is communicated with the heat-preserving chamber and the sample pipe, a cavity used for holding a to-be-determined sample is arranged in the sample container, and freezing liquid is arranged in the heat-preserving chamber and the sample pipe. According to the invention, the freezing liquid in the heat-preserving chamber and the sample pipe can be cooled by only opening the cold bath and setting a chilling temperature, so operation is easy and convenient; since a telescopic elastic rubber sleeve is wrapped over the sample, the sample can expand in three-dimensional space without restriction during freezing, so the accurate volume frost-heaving ratio of frozen soil can be obtained.

The invention discloses a construction method of building anti-permeability channels using soil curing agent. The method comprises the following steps: blending soil, a soil curing agent, water and fiber to form a curing soil mixing material; and dividing the curing soil mixing material into dry and solid curing soil and plastic curing soil by the water content of the curing soil mixing material, compacting the dry and solid curing soil with tamp equipment to form an intensive strengthened soil anti-permeability layer, and as for the plastic curing soil, adopting cement mortar spray gun technology to muddy spray curing soil to channel base to form a strengthened soil anti-permeability layer, further laying cement mortar on the surface of the strengthened soil anti-permeability layer to form a protection layer, so that frost heaving and destruction of anti-permeability channels in northern cold area can be effectively avoided. The method can solve the problem in the prior construction method of building anti-permeability channels using soil curing agent, increase construction speed of building anti-permeability channels using the soil curing agent, reduce the construction cost, and prolong the service life of the channels. The invention is of great significance for the development of water-saving irrigation and establishment of conservation-oriented society.

The invention discloses a cement concrete antifreezer, which comprises the following components in part by weight: 15 to 30 parts of high-performance polycarboxylate water reducer, 20 to 30 parts of low molecular weight alcohol, 0.1 to 0.15 part of triterpenoid saponins, 10 to 30 parts of calcium formate, 2 to 5 parts of organic alkylol amine and 50 to 70 parts of water, wherein the triterpenoid saponins is used for entraining air to form a large number of superfine air bubbles and improve the frost heaving stress of concrete. By the cement concrete antifreezer, the concrete can be subjected to construction at the temperature of between -20 and -30 DEG C.

The invention discloses a static and dynamic comprehensive test system considering soil expansion and contraction characteristics under temperature gradient. A temperature controlled circulating cavity at the upper end of a sample is used for carrying out low temperature freezing and warming thawing on the sample, so as to simulate the phenomenon of frost heave and thawing settlement in combination with actual implementation; the humidity change of the sample is accurately controlled by means of vapor, so as to better simulate the phenomenon of dry shrinkage and wet expansion in actual engineering; an electron microscope which can freely rotate and go up and down is designed to omnidirectionally scan the side of the sample, and is used for assisting in observing the changes of the internalstructure of the sample caused by the change of an external environment and provide theoretical support for the analysis of the change of physical and mechanical properties; a creative design of a double-layer silicone oil ring is proposed to improve the test accuracy, so as to obtain effective expansion force; in addition, optical fiber is arranged on the side wall of the sample to monitor temperature accurately, and in combination with a local strain sensor on the outer side of the sample, the overall strain of the sample is monitored comprehensively; the practical value and promotion valueof the static and dynamic comprehensive test system are high, and is of great significance for indoor simulation of freeze thawing and expansion and contraction of expansive soil and monitoring on changes of various indicators.

The invention relates to a construction method for utilizing a grouting freezing pipe to reinforce and freeze a contact passage to restrain frost heaving and thaw collapsing. A freezing pipe is used as a grouting pipe simultaneously, the grouting freezing pipe is characterized by being composed of the grouting pipe I and a liquid supply pipe II, wherein the grouting pipe I is composed of 3-6 sections, a drill bit III is installed at the pipe end of the first section, and the two sides of a pipe body are each provided with a one-way valve IV; the liquid supply pipe II is formed by two steel pipes in a crossed and welded mode, a certain amount of cement paste is added into and mixed with the soil body to improve physical and mechanical properties of the soil body, and the influence of frost heaving and thaw collapsing on surrounding strata and buildings can be restrained when contact passage freezing reinforcement is conducted. The construction method comprises the steps of construction preparation, positioning and drilling, grouting, liquid supply pipe installation, refrigerating system installation and freezing by starting a machine after maintenance. The construction method has the advantages that the cement soil is utilized for reinforcement, the strength of the soil body is further strengthened, the anti-permeability and the self-stability capacity of the soil body and the water stop performance of the contact passage strata are enhanced, groundwater seepage is effectively controlled, and the safety of later excavation and construction is improved.

The invention discloses a structure system for reducing tunnel lining frost heaving force in a cold region and belongs to the field of tunneling freezing damage prevention in the cold region. The structure system sequentially comprises tunnel primary lining concrete, a composite geotechnical cloth water-proof layer, a buffering layer and a secondary lining from the inside to the outside. The buffering layer is composed of a polyethylene foam lining and fiber-reinforced foam concrete. The polyethylene foam lining is paved and fixed on the surface of the water-proof layer in a close bonding mode. The fiber-reinforced foam concrete is poured outside the polyethylene foam lining. When underground water is frozen to become ice, the buffering layer structure can have a heat preservation effect and relieve the frosting of the underground water. When the underground water is frozen, the buffering layer has a buffering effect on the frost heaving force exerted on the secondary lining structure through self-deformation so as to reduce stress and deformation of the secondary lining, prevent cracking and achieve the purpose of preventing freezing damage to a tunnel structure.

The invention discloses a pile side negative friction resistance test device in frozen earth areas and an application method thereof. The device consists of a top cover, a top plate, a gauge stand, a dial indicator, a screw, a hollow pile, a settlement pole, a moisture transducer, a double-layer steel drum, a foil gauge A, a foil gauge B, a soil sample, inorganic thermal mortar, a bottom plate, medium sand, a moisturizing device, a pool, a refrigerator, a refrigerating tube, a frost heave thaw collapse meter and a temperature sensor. According to the device, the refrigerator is used for manpower refrigeration, the atmospheric temperature under various working conditions can be simulated, and the temperature and frost heave quantity of the soil sample can be accurately measured in real time by using the temperature sensor and the frost heave thaw collapse meter, so that the influence on the negative friction resistance by the frost heave quantity is avoided, and the test result is more precise.

The invention relates to a device and a method for testing the internal frost-heave capacity of compacted soil, relating to a device and a method for testing the frost-heave capacity. The device and the method are used for solving the following problems: the frost-heave deformation in a soil body cannot be tested in the existing frost-heave testing process and the soil body cannot be frosted from top to bottom. The device disclosed by the invention is characterized in that foam plates are uniformly arranged on the inner surface of a square tank; a thermal insulation layer is arranged at the inner side of each foam plate; a soil sample circular tank is arranged in the centre of the thermal insulation layer; a semi-permeable membrane is arranged on the bottom surface of the soil sample circular tank; a water replenishing layer is arranged at the lower end of the semi-permeable membrane; a plurality of temperature sensors are uniformly arranged on the inner side wall of the soil sample circular tank along the axial direction; a sleeve is inserted in the central axis of the soil sample circular tank; and a plurality of probes are uniformly distributed in the sleeve spirally. The method disclosed by the invention comprises the following steps: compacting and forming a test soil sample; fixing the test soil sample; feeding probes; measuring the initial heights of the probes; frosting the test soil sample; recording displacement variation; and calculating the frost-heave rate. The device and the method disclosed by the invention are used for testing the internal frost-heave capacity of compacted soil.

The invention discloses an insulation construction method for a frozen-earth roadbed, which comprises the steps of: (1) carrying out excavating and replacing-filling construction; (2) laying a sand mattress layer, an insulation board, a geotextile and a geogrid; (3) burying temperature sensors; and (4) performing regular temperature observation. The insulation construction method for the frozen-earth roadbed relates to a construction method of setting a thermal insulation layer in a permafrost section, which is capable of controlling disturbance on a permafrost layer effectively, and maintaining property stability of the permafrost layer, thereby enhancing the overall stability of a roadbed, preventing the roadbed in the permafrost section from damages of subsidence, frost heave, pavement cracking, collapse, and the like, reducing replacing-filling thickness, saving construction cost, and shorting construction period under the same conditions.

The invention discloses a rock and earth mass frost heaving parameter in-situ tester. The tester comprises a test probe, a control device and a data collection device. The test probe comprises a hollow shaft, an elastic air bag, a thermal insulation layer, a heat exchange sheet and a protection sleeve which are distributed in order from inside to outside. The upper end and the lower end of the elastic air bag are fixed on the hollow shaft through flanges. A frost heaving force monitoring device and a frost heaving displacement monitoring device are arranged between the hollow shaft and the air bag. The control device comprises a temperature control device and a pressure control device. The temperature control device is connected with the heat exchange sheet through a thermal insulation pipe. The pressure control device is connected with the elastic air bag through a pressure pipe. The data collection device is connected with a sensor arranged on the test probe. The tester has advantages of accurate result, low cost, easy operation and the like.

The invention discloses a rock fracture frost heaving deformation testing device. The bottom of a bottom plate is provided with screw holes, and bases are mounted at the bottom of the bottom plate. A frame is welded to the bottom plate. A fastening support and a fastening stop dog are welded to the bottom plate. A fastening bolt is mounted on the fastening support. A rubber gasket is arranged at the tail end of the fastening bolt. Locating stop dogs are welded to the bottom plate. The two ends of each test point fixing web are welded to the bottom plate and the frame respectively. The fixing webs are provided with slide grooves and compensation block containing grooves. Slide blocks are arranged at the two ends of a strain sheet laying strip and embedded in the slide grooves. Test point locating screws are arranged on the slide blocks. A strain sheet is pasted to the strain sheet laying strip and connected with a wire. A temperature compensation strain sheet is pasted to quartz glass. A wire laying plate is mounted between the bottom plate and the frame. The wire is led out of the wire laying plate. The rock fracture frost heaving deformation testing device is simple in structure, high in test accuracy and capable of accurately and continuously testing frost heaving deformation of rock mass factures in the frost heaving process to obtain fracture deformation characteristics at different frost heaving stages.

The invention discloses a full-automatic frost heaving meter which comprises a host loading frame (1), a freezing pressure chamber (2) and a high-low temperature cycle control system (3), a water level control system (4) and a computer (5). The freezing pressure chamber (2) is positioned on the host loading frame (1), the high-low temperature cycle control system (3) is connected with the freezing pressure chamber (2), the water level control system (4) is connected to the top of the freezing pressure chamber (2), and the computer (5) is connected with the water level control system (4), the host loading frame (1) and the high-low temperature cycle control system (3) and can be used for test control and acquisition. The full-automatic frost heaving meter can realize automatic control and acquisition of the test process, the requirement of high precision of test control in test can be effectively met by servo closed loop control, and the full-automatic frost heaving meter is high in stability and long in service life.

The invention discloses a one-dimensional soil column frost heave deformation tester, the one-dimensional soil column frost heave deformation tester comprises an organic glass mould for containing a one-dimensional cylindrical soil column, a circulator for soil column frost heaving through refrigeration, a test device for soil column frost heave deformation in the frost heaving process, a monitoring device for real-time monitoring of internal temperature change of a soil sample along the soil column height change in the refrigeration process, a water replenishing device for simulation of replenishing groundwater into the soil column from bottom to up, a drainage device, a testing device for testing the pore water pressure of the soil column in the process of frost heaving, and a data acquisition system; the one-dimensional soil column is a cylindrical soil sample, the mould for containing the one-dimensional cylindrical soil column is vertically-arranged cylindrical double-layer transparent organic glass, and the water replenishing device is connected with the bottom of the one-dimensional cylindrical soil column by a water replenishing pipe. The one-dimensional soil column frost heave deformation tester has the advantages of simple structure, reasonable design, practical operation and good practical effect, can simulate the indoor soil frost heave deformation process, and can effectively test soil body internal temperature, pore water pressure, vertical frost-heave capacity, vertical volume deformation and frost heaving force.

The invention discloses a device for testing fracture frost heaving force of rock under the vertical load effect. The device comprises a thermal-insulation bearing base, a drawer type side wall steelframe, a vertical pressurization steel plate, a hydraulic jack, a steel plate, a thermal-insulation cover, a cold air delivery pipe, a flaky pressure sensor and a needle-like temperature sensor. The device is simple in structure, convenient to produce and mount and easy to operate; the mounting accuracy of the pressure sensor is high and measurement errors are controllable; the change of water-saturated fracture frost heaving force in multiple rock samples can be measured continuously; an effective experimental method is provided for testing the fracture frost heaving force under the verticalload effect.