172 results about "Shear strength (soil)" patented technology

The invention relates to a method for treating landslide projects through combining a chemical electroosmosis method with micro anti-slide piles. The method comprises the following steps of: arranging metal electrodes and pouring different chemical solutions in boreholes and forming electroosmosis and chemical reaction under the action of a direct current field so as to enhance the shear strengthof potential failure surfaces of sliding zones; and then casting concrete in the boreholes and forming a micro reinforced concrete anti-slide pile system so as to provide a slide-resisting force. Themethod for treating the landslide projects through combining the chemical electroosmosis method with the micro anti-slide piles has the advantages and effects that: through carrying out electroosmosis reinforcement on the soft soil layers of potential landslide zones by using the chemical electroosmosis method, the coefficient of the shear strength of the potential landslide zones is remarkably increased, and the processing cost for the anti-slide piles or other treatment methods is effectively reduced; the bore diameter of the boreholes required by the micro anti-slide piles is small and themicro anti-slide piles are formed in identical boreholes to those for the chemical electroosmosis method through sequentially constructing, thus the difficulty and the cost for boring are low; and the shear strength and the slide-resisting force for landslide sliding zones are effectively enhanced. The method provided by the invention has the characteristics of simple construction technology, strong operability, convenience for quality control, obvious economic benefit and remarkable effect for treating landslides.

The invention provides a stability analysis method for hydromechanical coupling of an unsaturated soil slope, and belongs to the technical field of rock and soil. According to the stability analysis method, a Barcelona basic model more conforming to the property of the unsaturated soil is adopted for a constitutive model of the unsaturated soil, and the influence of suction force and the influenceof shear strength and compressive strength of a soil body are considered in the constitutive model. According to the strength reduction method for unsaturated soil slope stability analysis, the shearstrength of a soil body is reduced by reducing the cohesive force and the friction angle of the soil body. In addition, the reduction of the compressive strength of the soil body is taken into account by reducing the consolidation pressure in front of the soil body. The stability analysis of the unsaturated soil slope is carried out under the Cosserat continuum frame, and the influence of the microstructure effect of the soil body on the stability of the macroscopic slope is considered to a certain extent. According to the stability analysis method, various influence factors are considered, and the stability analysis accuracy of the unsaturated soil slope is improved.

The invention discloses a liquefiable foundation device for micro-nano bubble processing and an operation method. In terms of a liquefiable sand layer in a foundation, a mixture of micro-nano bubbles and water is injected through a micro-nano gas-liquid mixture generator, a compressor, an air guide pipe, a hollow drilling pipe, a gas sprayer and the like, the micro-nano bubbles can stay in soil for a long time, the saturation is reduced, shearing strength of the soil is enhanced, and accordingly liquefaction resistance of the liquefiable sand layer is remarkably improved. When the liquefiable sand layer bears a vibration load, gas left in the soil can serve as a buffering agent and effectively buffer the tendency that pore water pressure rises, and accordingly the liquefaction resistance of the foundation is improved.

The invention discloses an in-situ measurement method for the shear strength of a soil body and an automatic remote real-time measurement system thereof. The in-situ measurement method comprises the steps of obtaining a shear wave velocity through a pair of shear wave velocity measurement piezoelectric patches according to a piezoelectric effect; measuring the moisture content of the soil body through a soil body moisture content sensor; obtaining the shear strength of the soil body according to a relation among the shear wave velocity, the moisture content of the soil body and the shear strength of the soil body. Exciting and receiving signals of the pair of the shear wave velocity measurement piezoelectric patches are connected with a micro controller through a phase discriminator and then are sent to an upper computer through a remote signal sending circuit and a remote signal receiving circuit; all devices are powered by a storage battery; the storage battery is connected with a solar power supply device. The shear strength of the soil body is measured according to the shear wave velocity of the soil body and the moisture content of the soil body; in-situ, remote, real-time and automatic measurement is executed; an on-site, real-time and remote monitoring means is supplied to observation of possible catastrophe processes of landslide and debris flow hidden points, research on the rule of the landslide and debris flow disasters and final forecast of the landslide and debris flow disasters.

During triaxial compression test, a soil specimen experiences reduction of its height with increase in its diameter. New cross-sectional area is calculated assuming uniform increase in diameter. This condition is seldom met in actual soil specimens, because specimen undergoes non-uniform increase in diameter and very often with localized bulging in specimen affecting the accuracy of calculation of deviator stress, shears strength and volume change characteristics. The expandable jacket included in this invention consists of circular segmental metal plates wrapped around the soil specimen and elastomeric rubber bands or rings around the segmental plates to permit uniform radial expansion and maintain uniform diameter of the specimen during the test and thereby providing accurate values of deviator stress, volume change characteristics and shear strength of soil specimen. The calibration device for calibration of expandable jacket shall provide the magnitude of correction to be made in deviator stress.

The invention belongs to the technical field of geotechnical engineering, and discloses a comprehensive prevention and control system applied to a gravel soil side slope. According to the comprehensive prevention and control system, the good slope anti-seepage effect is achieved by burying drainage blind pipes and rapid drainage pipes in a slope surface layer soil body, arranging an intercepting ditch at the top of the slope, arranging a drainage channel at the foot of the slope and performing planting and greening on the slope surface, and the influence of surface water infiltration such as rainfall on the slope stability is reduced; after spring type spiral steel bars are put into pile holes, concrete doped with an expanding agent is poured into the pile holes to form miniature anti-slide piles, prestressed anchor cables are arranged to improve the shear strength of the side slope, and the stability among a potential sliding surface upper landslide mass, a potential sliding belt anda lower stable soil mass is enhanced; a plain concrete retaining wall is arranged at the foot of the slope to support the side slope, and a deep drainage pipe is drilled in the concentrated seepage area to effectively cut off the concentrated seepage, and water is collected and guided out of the slope; and finally, the anti-seepage drainage and reinforcement effects on the side slope are remarkable, and compared with traditional electro-osmosis drainage, energy consumption is reduced, economic benefits are remarkable, and operability is high.

The invention discloses a drawing type soil layer shearing strength testing device and a method for testing by using the same. The drawing type soil layer shearing strength testing device comprises a base, a drawing type soil layer shearing strength tester, a drawing rod and a displacement sensor and is characterized in that the base and the drawing type soil layer shearing strength tester are arranged on a test point of a soil layer, a connecting rod joint of the drawing type soil layer shearing strength tester is connected with the drawing rod placed in the soil layer, a hand wheel of the drawing type soil layer shearing strength tester is rotated to lift the drawing rod until the soil layer is sheared, and the shearing strength of the soil layer is tested. The drawing type soil layer shearing strength testing device and the method for testing by using the same are suitable for in-site test of total dewatering-free shearing strength of soil layers such as a foundation pit, a side slope and the like and rapidly making engineering evaluation on the soil layers.

The invention relates to the field of slope engineering stability evaluation, in particular to a slope shear strength parameter inversion analysis method based on equivalent soil pressure action, the method comprises the following steps: acquiring rock mass material parameters, rock mass test data and monitoring data; establishing a numerical calculation model according to slope field data; performing rock mass shear strength parameter inversion analysis in a soil initial stress field by using the numerical calculation model; comparing the slope stress field with the initial ground stress field under the action of the equivalent soil pressure, and carrying out inversion analysis on the shear strength parameters c and phi of the rock mass again; correcting the initial parameters through the inversion parameters, and obtaining the shear strength parameter cohesive force c and the internal friction angle phi of the rock mass. According to the method, in parameter inversion analysis of the side slope with the covering layer, the slope pressing effect of the covering layer is considered, the problem that the rock mass inversion parameters cannot be obtained due to the fact that the sliding surface is always in the covering layer due to the fact that the parameters of the covering layer are relatively low is solved, and then the shear strength parameters of the rock mass can be obtained more accurately and reasonably.

The invention discloses a progressive dry-wet cycle test device, comprising a water supply container, a soil column system and a ventilation system, wherein the soil column system is connected with the water supply container, and the ventilation system is connected with the soil column system. The water supply container includes a concentrically arranged water container and the circulating water container, the soil column system includes a base, a bottom layer and several standard layers connected together, and the ventilation system includes Breathing tube with vent holes. The invention also discloses the use method of the test device. Through the above-mentioned test device and its use method, the dry-wet cycle method is in line with the actual working conditions of the project, and the accuracy of the test results is improved. The soil sample and its shear strength parameters are obtained, and the ventilation through holes are set on the wall of the ventilation pipe and the wall of the standard layer, which shortens the cycle of drying and wetting.