356 results about "Consolidation (soil)" patented technology

The invention discloses a building foundation settlement and stability long-term monitoring method and system. According to the method, building settlement related data are collected through a distributed optical fiber sensing network, an inclination sensor array and a soil pressure sensor; establishing a soil stress memory effect calculation model, and calculating effective stress considering the memory effect; constructing a building foundation settlement total model containing main consolidation settlement, creep settlement and additional settlement caused by environmental factors; according to the method, risk grade division is carried out based on multi-level threshold values, early warning advance is calculated, an emergency response strategy is generated, intelligent monitoring and early warning of building foundation settlement are achieved, and the method has important engineering application value.

The embodiment of the invention discloses a numerical simulation method for water-rich stratum foundation pit engineering settlement. The method comprises the steps that computational grids and soil mass parameters of a water-rich stratum foundation pit engineering numerical model are obtained; carrying out numerical calculation on the computational grid to obtain distribution conditions of stress and a seepage field; calculating a permeability coefficient and a compression coefficient in the current soil body state; calculating dynamic pore water pressure and steady-state pore water pressure; calculating soil deformation according to the compression coefficient, the dynamic pore water pressure and the steady-state pore water pressure; and carrying out consolidation analysis according to the permeability coefficient. According to the embodiment, the consolidation deformation condition of the soil body in the complex construction process can be accurately predicted.

The invention belongs to the technical field of ocean geotechnical engineering, and discloses full-strain range soil body strength characteristic testing equipment and a testing method for simulating a deep sea temperature and pressure environment. The system comprises an integrated probe, a stepping motor, a linear module, a hollow probe rod, a torsion module, a loading platform, a sample box, a water depth simulation system and a temperature control system. The hydraulic source and the temperature controller are used for simulating the deep sea low-temperature and high-pressure environment, the simulation effect is good, soil sample visualization is achieved, static sounding and vane shear tests are combined by designing the integrated probe, the soil permeability coefficient, the consolidation coefficient, the undrained shear strength and the sensitivity are measured, the precision and the efficiency of soil parameter analysis are improved, and the method is suitable for popularization and application. And data complementation, efficiency optimization and precision improvement are realized.

The invention discloses a narrow foundation pit upheaval resistance stability calculation method, which comprises the following steps: acquiring actual length, width and depth dimensions of a foundation pit and a consolidation undrained strength index, cohesion ccu and an internal friction angle phi cu of a field soil layer, and calculating a type critical width according to an improvement formula considering the internal friction angle of soil and a first width calculation coefficient, and whether the foundation pit is the narrow foundation pit or not is determined according to the comparison result of the actual foundation pit width and the type critical width. When the actual foundation pit is determined to be the narrow foundation pit, the width of a sinking soil body on the side face of the foundation pit is reversely solved through an improvement formula considering the internal friction angle of soil and the width of the actual foundation pit, and the upheaval-resistant stability coefficient of the narrow foundation pit based on the foundation bearing capacity mode is calculated and compared with the upheaval-resistant stability coefficient of the arc sliding mode. And taking the smaller value as the anti-upheaval stability coefficient of the narrow foundation pit so as to evaluate the anti-upheaval stability of the pit bottom of the foundation pit. Therefore, the problems that in the related technology, the judgment standard of the narrow foundation pit and selection of the slip plane are unreasonable, preconditions for checking calculation according to the narrow foundation pit design are unknown, and the friction angle in the stratum is not considered are solved.

The invention discloses a method for measuring lateral expansive force of expansive soil. The method comprises the following steps: manufacturing a plurality of groups of expansive soil test pieces with the same dry density and initial water content; the atmospheric influence depth is determined, and the overburden pressure of the soil body is determined according to the point positions where the lateral expansive force needs to be calculated in the atmospheric influence depth after the retaining structure is supported; a plurality of overburden pressure lateral confinement loaded expansion rate tests are conducted according to a standard method, and a relational expression among the water content increment, the overburden pressure and the loaded expansion rate is established; by improving a K0 consolidation test, the loaded expansion rate and the lateral expansion force of the soil body in the humidifying process under the action of overburden pressure are measured; substituting the result of the improved K0 consolidation test into the relational expression obtained by the lateral confinement load expansion rate test, and calculating to obtain the water content increment corresponding to the load expansion rate in the soil body humidifying process of the improved K0 consolidation test; and fitting to obtain a relational expression among the lateral expansive force, the overburden pressure and the water content increment. According to the method, the lateral expansion force at different depths behind the rigid retaining structure can be calculated.

The invention relates to the field of soft soil foundation construction, in particular to a sealing wall construction method for a soft soil foundation, which comprises the following steps of: calibrating a plurality of detection points in a target construction area, carrying out jet impact detection on the detection points, and determining soil impact sensitive characteristics; according to the soil impact sensitive characteristics, determining an impact sensitive characterization value of soil in a target construction area so as to divide impact sensitive categories of the soil in the target construction area; drilling a grouting pipe with a nozzle into a preset position of soil in the target construction area by using a drilling machine, controlling the drilling machine to act based on the impact sensitive type, grouting the soil and forming a sealing wall column consolidation body, and if the impact sensitive type is weak sensitive, simultaneously adjusting the lifting speed of a drill bit of the drilling machine and the spraying strength of the nozzle to form the sealing wall column consolidation body. The problem that the construction process is affected due to different impact sensitivities of soil is solved, and then the construction quality and efficiency of sealing wall construction of the soft soil foundation are improved.

The invention discloses an in-situ monitoring method for the soil consolidation and compression process of a loess fill foundation. The in-situ monitoring method comprises the following steps: 1, calibrating a TDR (Time Domain Reflectometer) probe; 2, excavating an embedding pit, a wire groove and a wire conduit embedding groove; 3, a soil pressure meter and a TDR probe are installed, and soil is taken; 4, arranging the cables; 5, backfilling the burying pit, the wiring trough and the wiring tube burying groove; 6, measuring data of the installed soil pressure gauges and the TDR probes, and installing the soil pressure gauges and the TDR probes on the upper layer in the newly backfilled soil layer; seventhly, the sixth step is repeated for multiple times till the designed elevation is achieved through backfilling; 8, data are collected and recorded at fixed time intervals, the water content and the dry density of each layer of filling soil of the filling body are calculated, and then the compression coefficient, the compression modulus and the settling volume of the layer of filling soil are calculated. According to the method, the process that the soil volume is reduced and the density is increased due to the fact that the arrangement compactness degree between soil particles is increased and the porosity is reduced when the filled foundation soil is subjected to the external load effect is reflected from the angle of soil mechanics.

The invention belongs to the technical field of tunnel engineering, and particularly relates to shield tunneling machine anti-drag slurry for stacked tunnel construction and a use method of the shield tunneling machine anti-drag slurry. According to the anti-drag slurry, bentonite, anhydrous Na2CO3 and water are used as main raw materials, a certain amount of a lubricant and a nanometer material are added into the slurry to prepare the anti-drag slurry, the stress condition between a shield tunneling machine shell and a soil body is monitored in real time, the grouting amount and the grouting pressure of the anti-drag slurry are dynamically adjusted according to the change of soil pressure, and therefore the anti-drag effect of the shield tunneling machine is achieved. The friction force between the shield tunneling machine shell and the surrounding soil body can be reduced, disturbance of the shield tunneling machine shell to the soil body is reduced, consolidation settlement of the soil body in the later period is reduced, and materials and methods are provided for stacked tunnel construction.

The invention relates to the technical field of tunnel construction, in particular to a construction method for a double-track tunnel to pass through basalt with tuff in a water-rich section. Comprising the following steps: S1, tuff identification; s2, advanced geological forecast; s3, closing the tunnel face; s4, a forepoling system is established; S5, a tunnel body is excavated, wherein a three-step method is adopted as an excavation construction method; s6, reinforcing a steel frame lock leg support; s7, support parameters are determined; s8, arranging drainage holes; and S9, monitoring and measuring. A plurality of supporting systems are formed, the supporting effect is good, combination with the soil body is stable, the water plugging consolidation effect is obvious, and construction is safe and reliable; the supporting method and the grouting means are organically combined, the procedure connection continuity is good, safety is high, the application range is wide, the construction speed is high, and safety performance is high. The construction method is mainly applied to the construction aspect of the double-track tunnel crossing the basalt and tuff in the water-rich section.

The invention relates to a water-rich soft soil stratum deep foundation pit dewatering excavation coupling analysis method. The method comprises the steps that an SOIL module on a large-scale commercial finite element software ABAQUS calculation platform is used, a Biot consolidation control equation is adopted to describe the coupling effect of soft soil stress-pore unsteady flow under foundation pit dewatering excavation, a finite element model is established, and in combination with field monitoring experience of foundation pit excavation construction on an adjacent environment influence range, an in-pit dewatering mode is adopted to determine the soft soil stress-pore unsteady flow coupling effect under foundation pit dewatering excavation. The calculation time and the calculation precision are comprehensively considered, and step-by-step refined simulation in the foundation pit construction process is achieved. According to the method, the fluid-solid coupling effect in the dewatering excavation process of the deep foundation pit in the water-rich soft soil stratum can be accurately simulated, the influence of foundation pit excavation on the surrounding environment is effectively predicted, and the engineering safety and reliability are improved.

The invention discloses transparent soil with high transparency and high similarity with natural soil and a preparation method of the transparent soil. The transparent soil comprises transparent particles, transparent pore liquid and an additive. The refractive indexes of the transparent particles and the transparent pore liquid are consistent, and the contact infiltration characteristic of the particle surfaces and the liquid is improved through the surfactant, so that the transparent soil with higher transparency, such as sandy soil, clay and floury soil, is obtained. Hydrophilic fumed silica is matched with polar pore liquid or hydrophobic fumed silica is matched with non-polar pore liquid to prepare high-strength transparent clay or silt with mechanical properties highly similar to those of natural clay or silt. According to the invention, the clay or silt consolidation time can be greatly shortened. The transparent soil with high transparency and high similarity with natural soil can improve the geometric dimension of a transparent soil model, reduce the dimension difference between a model test and a real engineering problem, and provide a more excellent method for researching various geotechnical geological engineering problems.

The invention relates to the technical field of environmental protection, in particular to a cooperative soil fixation system and method based on a grass planting slope protection root system and a grating, and the system comprises a root system distribution optimization module, a grating structure adaptation module, a soil fixation capability improvement module, a slope stability evaluation module and a dynamic adjustment module. According to the method, priority distribution is constructed by extracting a root system supporting strength key section and combining root system depth and density changes, accurate recognition and differential layout of soil structure characteristics are achieved, a stress adaptation relation is established by matching grating parameters of all areas, the soil bearing and supporting coordination degree is improved, and the accuracy of the soil structure characteristics is improved. A soil fixation capability concentration area is extracted based on consolidation change and root trend, accurate evaluation of consolidation strength per unit area is realized, slope stability effectiveness is monitored by identifying a water flow scouring and stability change coincidence period, disturbance tasks are classified, grid switching frequency is dynamically adjusted, response efficiency and anti-interference capability under sudden change load are enhanced, and slope stability evaluation is realized. The problem that a traditional soil fixing structure is insufficient in adaptability is solved.

The invention provides a cohesive soil early consolidation pressure detection method and device, and belongs to the technical field of geotechnical engineering detection.The cohesive soil early consolidation pressure detection method comprises the steps that a structured database is established based on engineering area historical drilling data and geotechnical test data; extracting data subsets corresponding to the soil texture types from the database, and respectively constructing mucky soil and conventional cohesive soil early consolidation pressure prediction models; acquiring a standard volume soil sample and density and water content data thereof; drilling position coordinates, orifice elevation, sampling depth and soil sample specific gravity parameters are input; selecting a prediction model according to the soil texture type, inputting related data, and outputting an early consolidation pressure value; and comparing the early consolidation pressure value with the current effective self-weight stress, and judging the consolidation state of the soil body. According to the method, the detection period of the early consolidation pressure of the cohesive soil body is shortened, subjective factors in the manual curve drawing process are eliminated, and the data accuracy and the working efficiency are improved.

The invention discloses a powder spraying pile composite roadbed deformation prediction method, and particularly relates to the field of roadbed settlement prediction, comprising the following steps: in an edge calculation node, respectively constructing an underground water level change event, a construction stage event, a soil consolidation stage event and a traffic load cycle event into independent event time chains; the event time chain is recorded by taking the occurrence moment of the event, the duration of the event and the interval duration between the events as a time step unit; and performing splitting operation on the time step units of each event time chain, and forming a time granularity matrix according to the duration difference between the time step units. A plurality of types of discrete events such as water level, construction, consolidation, traffic load and the like are uniformly disassembled into time step length units, and a time granularity matrix and a time dislocation vector are constructed, so that the rhythm difference and dislocation relationship of the events on different time scales can be quantitatively expressed; and solving the transition of the settlement stage by taking the result as the observation input of the variational Markov model.

The invention relates to the technical field of civil engineering, in particular to an energy-saving and environment-friendly vacuum preloading foundation treatment method which comprises the steps that a foundation soil body is divided into a plurality of foundation units, and a plurality of vacuum pumps are installed according to initial operation parameters; pre-suction is conducted on the foundation, the vacuum state of any foundation unit is judged, the suction power or the predicted demand power of the corresponding vacuum pump is adjusted, and the under-membrane vacuum pressure of the foundation unit is measured for the second time; the consolidation state of the foundation unit is judged according to the pore water pressure, and the fluctuation of pore water pressure change is detected to determine the foundation consolidation stage; drawing an intra-membrane vacuum pressure change curve in the main consolidation stage, judging the change trend of the curve, and determining the stability of the intra-membrane vacuum pressure and the working state of the sealing membrane according to the fluctuation of the curve; and in the secondary consolidation stage, the ground subsidence height is measured to predict whether the vacuum preloading reaches the load required by the design or not. By evaluating the consolidation degree and stability of the foundation soil body, the efficiency and accuracy of vacuum preloading treatment are improved.

The invention discloses a vibration pressurization drainage consolidation test device for ultra-soft soil. The vibration pressurization drainage consolidation test device comprises a consolidation container, a vibration unit, a pressurization system and a test unit, wherein a water outlet hole is formed in the bottom of the consolidation container, and a vertical drainage belt is arranged on the side wall of the consolidation container; the vibration unit comprises a vibrator; the test unit comprises a pressurizing frame, a pressurizing sensor, a displacement meter and a pressurizing cover plate, and the pressurizing cover plate covers the top of the consolidation container and applies pressure to the ultra-soft soil sample; the test system comprises a pore water pressure sensor and a displacement meter; a pore water pressure sensor is arranged on the side wall of the consolidation container, and a displacement meter is used for monitoring the downward moving distance of the pressurizing cover plate along with consolidation of the ultra-soft soil in real time. The invention further provides a vibration pressurizing drainage consolidation test method for the ultra-soft soil, water permeable plates are arranged on the upper portion and the lower portion of the ultra-soft soil sample, and a drainage belt is arranged on the side face of the ultra-soft soil sample; a complete drainage channel is formed, water can be drained in time, and rapid drainage consolidation is achieved.

The invention relates to a large-strain consolidation algorithm, equipment and medium for horizontal vacuum dehydration of sludge, and the algorithm comprises the following steps: 1, obtaining basic parameters of a constitutive relation of a target soil body through an indoor consolidation experiment and a penetration experiment, 2, obtaining load conditions of the target soil body through surveying a geological exploration report and an engineering design scheme, the method comprises the steps of (1) establishing a one-dimensional PHD consolidation model, (2) establishing a one-dimensional PHD consolidation model and deducing a control equation under equal strain conditions, (3) introducing a virtual time step and calculating the consolidation degree in a manner of carrying out segmented increment processing on time, (4) establishing the one-dimensional PHD consolidation model and deducing a control equation under equal strain conditions, and (5) calculating the final consolidation degree based on the virtual time step and the control equation, and further comprises equipment and a medium. According to the method, the influence of non-uniform consolidation is incorporated into the one-dimensional theoretical consolidation analysis of the Taisha foundation, and the consolidation coefficient is corrected by using the control equation based on the virtual time step and the strain condition, so that convenient and accurate consolidation calculation is realized.

The invention discloses a vacuum preloading and dynamic compaction combined soft foundation treatment method which comprises the steps that a plurality of dynamic compaction holes are formed in a soft soil foundation construction site at intervals, vertical water pumping pipes are arranged in the dynamic compaction holes, and gaps between the vertical water pumping pipes and the dynamic compaction holes are filled with gravels; a plurality of vertical plastic drainage belts are arranged on the periphery of each dynamic compaction hole at intervals, and a sand layer is laid on the surface of the site and then covered with a film for sealing; the vertical plastic drainage belt in the thin film and the stratum are in a partial vacuum state through suction of a vacuum pump, and underground water is pumped and drained outwards; meanwhile, underground water in the dynamic compaction hole is sucked and discharged through a water suction pump and a vertical water suction pipe; and after first-stage vacuum preloading is completed, in-hole dynamic compaction operation is conducted on the dynamic compaction holes in sequence, gravel in the dynamic compaction holes is rammed through a conical rammer and extruded towards the outer side, and extrusion drainage consolidation of a soil body in the stratum is achieved. The method has the advantage that the construction efficiency of drainage consolidation of the soil body is improved in a vacuum preloading and dynamic compaction mode.

The utility model relates to a soil pressure gauge embedding structure for short pipe replacement construction, which comprises a probe hole arranged at the top and the side edge of a pipeline, a paddle binding bag arranged at the bottom of the probe hole, slurry in a soft plastic state filled in the paddle binding bag, and a soil pressure gauge arranged in the paddle binding bag and perpendicular to the radial direction of the pipeline. The soil pressure gauges in the probe holes right above the pipeline are horizontally arranged, and the soil pressure gauges in the probe holes on the two sides of the pipeline are laterally arranged, so that the formation pressure change can be effectively conducted to the soil pressure gauges, and the accuracy of monitoring results of the soil pressure gauges is ensured; the bottom of the water pumping pipe is wrapped with geotechnical cloth to prevent the sand from entering the water pumping pipe and blocking the water pumping pipe; the top of the water pumping hole is backfilled with clay to prevent surface water from entering a soil layer around the pipeline through the water pumping hole; the bearing capacity of the soil layer is reduced; and the pipeline structure safety is influenced.

The invention relates to the technical field of compaction pile construction, and discloses a construction method of an along-track bar hammer stone breaking compaction pile made of site original soil and stones, which is characterized by comprising the following steps: S1, foundation treatment is carried out; s2, a foundation pile is formed; s3, a composite foundation is formed; and S4, manufacturing a mattress layer, and coordinating settlement difference. According to the construction method disclosed by the invention, the hammer body can be used for completing the construction of all working procedures of trepanning and pile forming of the pile body (trepanning, stone breaking, soil squeezing, hole forming, chambering and pile end bearing layer manufacturing; the combined action of one hammer with multiple purposes, one machine with multiple purposes and one method with multiple purposes is achieved, the combined hammer can adapt to various different geological conditions and the design requirements of different buildings and structures, and meanwhile various miscellaneous fill rocks existing on the site can be converted into various miscellaneous fill rocks. Various effects (original soil and stone bodies, a dynamic consolidation construction method, pile bodies with different strengths, soil bodies among the piles and the like) formed after treatment are combined together to form a raft-shaped high-strength foundation bearing layer.

The invention relates to the technical field of immersed tunnels, in particular to an immersed tunnel settlement calculation method, system and medium under a sedimentation load.The method comprises the steps that basic assumption is made based on stress deformation characteristics of an immersed tunnel, and the circulation form of the sedimentation load is determined based on the basic assumption; obtaining a calculation expression of the siltation load changing along with time; calculating the non-linear consolidation settlement of the soil layer of the underlying foundation caused by the sedimentation load; through the compression modulus, the drainage distance, the consolidation coefficient and the cycle period of the foundation soil layer, a Taylor expansion is combined to obtain a calculation expression of foundation settlement changing along with time; based on the bending moment and the shearing force of the Timoshenko beam model, the deflection of the immersed tube tunnel with the different dredging frequencies is determined; determining a settlement value at the left end joint of any pipe joint and a settlement value at the right end joint of any pipe joint according to the transmission deflection difference and the rotation angle between the adjacent pipe joints in the immersed tunnel; according to the method, the calculation accuracy of immersed tunnel sedimentation caused by the sedimentation effect can be improved.

The utility model discloses a device for testing the bearing performance of a pile foundation under the simulated filling consolidation effect, which relates to the technical field of foundation engineering and comprises a model box, and the bottom of the model box is fixedly arranged on a base; a positioning column is arranged in the model box, a first loading disc is fixed to the top of the positioning column, an undisturbed soil layer is arranged between the first loading disc and the bottom in the model, and a backfill soil layer is arranged between the first loading disc and the top end of the model box; at least one second loading disc is arranged in the backfill soil layer space, a plurality of mounting holes are reserved in the second loading disc and the first loading disc, a drawing steel cable penetrating through the mounting holes is arranged in the model box, and the bottom of the drawing steel cable is connected with a loading device; a limiting stopper is fixed on the drawing steel cable, the limiting stopper can penetrate through the mounting hole together with the drawing steel cable when being closed, and the limiting stopper is matched with the mounting hole to limit the displacement of the loading disc when being opened; the loading mode and structure are simplified, quantitative load application can be rapidly and accurately achieved, and the accuracy of a simulation test is further improved.

The invention relates to the technical field of geotechnical engineering and geomechanics, in particular to a round gravel soil constitutive model construction method and system. The method comprises the following steps: performing a triaxial consolidation drainage experiment on round gravel soil to obtain mechanical test data of the round gravel soil; according to the mechanical test data, the Duncan-Chang model is improved; and based on the improved Duncan-Chang model, constructing a roundstone soil constitutive model. According to the method, by improving the curvilinear relation between the axial strain and the lateral strain of the Duncan-Chang model, the volume strain and the tangent Poisson's ratio, the applicability of the Duncan-Chang model to the round gravel soil is improved, and the problem that under the combined action of mountainous area alluviation and lacustrine facies deposition on the rushing-lacustrine round gravel soil, the model is difficult to deform is solved. The problem that an existing constitutive model cannot accurately describe the mechanical behavior of round gravel soil is solved.

The invention discloses a soil-water characteristic curve pressure plate instrument and a testing method, and relates to a soil-water characteristic curve pressure plate instrument which adopts a horizontal measuring tube, a newly designed upper gland and porous stone structure, a proportional valve and a PLC to apply air pressure step by step, and a testing method for testing a soil-water characteristic curve by using the soil-water characteristic curve pressure plate instrument. High-precision automatic control of stress loading in the test process and accurate measurement and recording of the consolidation displacement are realized; the influence of a position water head on the displacement in the dehumidification process and the water absorption in the moisture absorption process is overcome by adopting the horizontal measuring tube and setting the central height of the horizontal measuring tube to be consistent with the central height of the soil sample; the problem that the water discharge amount of the soil sample is small due to the influence of the position water head in the moisture discharge measurement process can be avoided, the problem that the water absorption amount of the soil sample is large due to the influence of the position water head in the moisture absorption measurement process can also be avoided, and the test precision and the test efficiency are improved.

The invention provides a consolidation test system and a consolidation test method, and relates to the technical field of road detection. The consolidation test system comprises a dynamic pore pressure test assembly, the dynamic pore pressure test assembly comprises a water source device, a dynamic pore pressure container part, a dynamic load displacement detection device and a dynamic load loading device, the dynamic pore pressure container part is provided with a pressurization cavity, a water inlet hole and a water outlet hole, the dynamic load loading device is provided with a load output end, and the load output end is arranged at the first end of the pressurization cavity in a sliding and penetrating mode; the load output end is matched with the pressurizing cavity in a dynamic sealing manner, the dynamic load loading device can apply a first load towards the second end to a soil sample in the pressurizing cavity, the water outlet hole is communicated with the second end of the pressurizing cavity, the water inlet hole is communicated with the first end of the pressurizing cavity, the water source device is communicated with the water inlet hole, and the dynamic load displacement detection device is connected with the load output end. Therefore, the displacement of the load output end is obtained. According to the invention, the key technical problems of soil consolidation characteristic test, permeability coefficient dynamic evolution rule analysis and the like under the dynamic load condition are solved.

The invention belongs to the technical field of soil detection, and particularly relates to a consolidation box with bending elements and a using method.The device comprises a consolidation unit, the upper portion of the consolidation unit makes contact with a loading rod of a conventional consolidation apparatus, a soil sample is arranged in the consolidation unit, and the upper end and the lower end of the soil sample are each provided with a bending element piece; the bending element sheet is fixed in the consolidation unit through bending element fixing bolts, the bending element fixing bolts at the upper end and the lower end of the soil sample are respectively connected with a bending element transmitting end and a bending element receiving end, the bending element transmitting end is electrically connected with a signal exciter, and the bending element receiving end is electrically connected with an oscilloscope; and the signal exciter is electrically connected with the oscilloscope. The bending element is used for measuring the small strain stiffness of the soil body in the test process. The device not only reserves the function of a traditional consolidation box, but also improves the capacity of capturing the small strain characteristic of the soil body by introducing the bending element, so that more accurate data support is provided for engineering practice.

The invention discloses a multifunctional testing device for a clay chemical permeation and consolidation test, and belongs to the technical field of rock testing, the device comprises a base, a rigid wall sample cylinder is arranged at the upper part of the base, a cap is arranged at the upper part of the rigid wall sample cylinder, and the wall cavity of the rigid wall sample cylinder is hollow; the temperature control is realized by circulating the circulating liquid of the temperature control module in the wall cavity; the device measures pressure through the pressure measuring module, supplements deionized water through the water supplementing module, and supplements a salt solution through the salt solution supplementing module. By adopting the device disclosed by the invention, proper modules are selected as required during testing, various rock and soil performance tests can be carried out, the testing device has various functions, multiple purposes are realized, and the testing cost is reduced. The rock-soil test method provided by the test device provided by the invention considers many factor indexes, can reflect complex environments in practical application more truly, has simple test steps, and can be popularized and applied in a large range.

The invention belongs to the technical field of underground passage construction, and particularly relates to a counter-force structure construction method for pipe roof jacking, which comprises the following steps of: driving support piles at two ends of a corresponding side line behind a working well to form corresponding counter-force columns; steel sheet piles are arranged between the two counter-force columns along the corresponding side line behind the working well in a driving mode, counter-force steel plates are installed on the counter-force walls, and grouting pipes penetrate through the counter-force steel plates, then stretch into the rear undisturbed soil from gaps between the steel sheet piles and are fixedly connected with the rear undisturbed soil into a whole through grouting. Through the synergistic effect of the counter-force column formed by the supporting piles and the undisturbed soil subjected to grouting consolidation, a composite counter-force system is constructed, and the bearing capacity and stability of the counter-force structure are effectively improved. The protection piles and the supporting piles are meshed with each other to form a closed or semi-closed structure, the stability of the soil body around the working well is further enhanced by matching with the reinforcing effect of the top beams and the inclined struts, and collapse or displacement of the soil body in the jacking process is avoided.

The invention relates to the technical field of geotechnical tests, and discloses a high-pressure consolidation leaching test device which is characterized in that a pressurization mechanism is arranged on a split soil sample cylinder assembly, an assembling mechanism is arranged on a water supply tank, pressurization mechanisms are arranged on a lower fixing plate and a middle fixing plate, a sliding table control screw is movably connected into an upper sliding table screw limiting stopper, and a lower sliding table screw limiting stopper is movably connected with a lower sliding table control screw; the surface of the sliding table control screw is in threaded connection with a sliding table, and the bottom of the U-shaped plate is fixedly connected with a weight. According to the high-pressure consolidation leaching test device, the lever principle is utilized, the pressure applied to a soil sample is adjusted according to the placement position and weight of the weight, the permeability coefficient of a soil body under different confining pressure conditions can be measured, and the mutual influence relation between seepage and consolidation when the soil body contains soluble minerals is measured. The lower pressurizing connecting piece is in bolted connection with the pressurizing screw rod, so that when the pressurizing screw rod transmits pressure, deviation or shaking caused by uneven stress can be avoided, the pressure is uniformly applied to a soil sample in the split soil sample cylinder assembly, and a test result is more accurate and repeatable.

An embodiment of the present invention discloses a numerical simulation method for the settlement of foundation pit engineering in water-rich strata, including: obtaining the calculation grid and soil parameters of the numerical model of foundation pit engineering in water-rich strata; performing numerical calculations on the calculation grid to obtain the distribution of stress and seepage field; calculating the permeability coefficient and compression coefficient under the current soil state; calculating the dynamic pore water pressure and steady-state pore water pressure; calculating the soil deformation according to the compression coefficient, dynamic pore water pressure and steady-state pore water pressure; and performing consolidation analysis according to the permeability coefficient. This embodiment can accurately predict the consolidation deformation of soil during complex construction processes.