69 results about "Subgrade soils" patented technology

The invention relates to the technical field of civil engineering, and discloses a road subgrade settlement prediction method and system based on multi-source data. The method comprises the following steps: acquiring and correcting a precipitation sequence and roadbed soil moisture distribution data; analyzing rainfall accumulation characteristics and carrying out penetration risk classification, thereby extracting a penetration depth estimation value, and utilizing finite element analysis to simulate a soil body saturation state change trend; quantifying a soil body supporting capacity reduction range, constructing and calibrating a settlement initiation probability calculation model, and obtaining settlement probability distribution; identifying a high-risk evolution area, integrating path weights and accumulated influence factors, and generating a settlement prediction interval subjected to multi-dimensional verification; and fusing the prediction interval and actual roadbed structure data through a geographic information system to generate a comprehensive evaluation report. According to the method, the whole-process accurate evaluation of the roadbed settlement risk from multi-source perception, mechanism simulation to space prediction is realized, and the accuracy and timeliness of the roadbed settlement risk prediction and the pertinence of engineering maintenance are improved.

The invention provides a drilling control method and system for a self-propelled complex drill bit, and the method comprises the steps: setting a rated cutting torque through obtaining roadbed soil, hydraulic power and geometric parameters, calculating the total propulsion resistance based on the roadbed strength to control the axial jacking force, and carrying out the safety verification of the drag force; calculating a critical flow velocity according to the characteristics of the drilling slag to adjust the discharge capacity and negative pressure of the slurry pump so as to determine an operation boundary; drilling and deslagging are cooperatively executed under the boundary, and the trajectory is corrected by combining a PID algorithm and the propulsion speed is optimized based on the theoretical mechanical drilling speed. According to the method, the technical problems that existing trenchless construction depends on experience to set parameters, scientific quantitative calculation of the slag discharge flow speed and the safety drag force is lacked, and then pipe cable blockage and drainage pipe damage are caused can be solved, and full-system cooperative efficient control of drilling, propelling, slag discharge and guiding based on multi-field coupling calculation is achieved.

A subgrade compaction pit soil-sampling device, comprising a frame (1) for providing support, upper and lower ends of the frame (1) being each provided with a cover plate (7), and a through hole being formed in the middle of each cover plate (7); a plurality of guide rails (4) arranged in the frame (1), two ends of each guide rail (4) being respectively connected to the upper and lower cover plates (7); a frame bucket (2) arranged at the bottom of the frame (1) and enclosing the bottom of the frame (1), the frame bucket (2) engaging with the lower cover plate (7) to form a cavity for accommodating subgrade soil extracted by a soil-sampling device; and the soil-sampling device (3) mounted on a guide rail plate (5), the guide rail plate (5) being cooperatively connected to the plurality of guide rails (4). A mechanical rotary drilling method is used to perform deep pit drilling of the subgrade, achieving high drilling efficiency, and after the drilling is finished, the soil can be extracted by reverse drilling, providing a convenient soil-sampling method.

The invention relates to the technical field of highway engineering, in particular to a method for predicting the dynamic resilience modulus of coarse-grained soil based on static index and dynamic modulus conversion, which specifically comprises the following steps of: testing various different types of roadbed soil samples to be tested; obtaining dynamic and static rebound modulus values of each subgrade soil sample under the conditions of optimal moisture content and set compaction degree and a relation between the dynamic rebound modulus value and CBR; establishing a dynamic and static modulus conversion equation; performing linearization processing on the dynamic and static modulus conversion equation, constructing a matrix equation based on a linearization processing result, solving the matrix equation by adopting a least square method to obtain regression constants k1, k2, k3 and k4, and substituting the regression constants into the dynamic and static modulus conversion equation; and constructing an equation by using the coarse-grained soil dynamic rebound modulus and the CBR value, and solving an equation regression constant to obtain a coarse-grained soil dynamic rebound modulus prediction formula. The problems that in the prior art, an existing conversion relation mechanism is insufficient in consideration, sample representativeness is limited, and the model generalization ability is weak are solved.

This invention provides a roadbed camber stress measuring device and method, relating to the field of roadbed camber stress measurement technology. It includes a base positioning component with two expansion limiting components installed at its bottom; these two expansion limiting components are used for hole enlargement; a firm verification component is installed inside the base positioning component; the firm verification component is used for elastically pushing the base positioning component; a measurement guide component is installed at the top of the base positioning component; a measurement compensation component is installed on the measurement guide component; the measurement compensation component is used to compensate for roadbed settlement. The measurement compensation component can be used to compensate for roadbed settlement. Because roadbed soil with strong rheological properties may settle first and then camber, if the roadbed settles first, the height of the settlement will cause a lack of camber monitoring, affecting the comprehensiveness of data monitoring. This invention solves the problem that current roadbed camber stress measuring devices are difficult to achieve firm monitoring of the anchoring end and are not convenient for automatically compensating for roadbed settlement.

The application belongs to the technical field of road and bridge joint construction, and particularly discloses a paving device for preventing and treating bridge-head bumping and a parameter determination method thereof, wherein the paving device comprises a bottom layer structure, the bottom layer structure comprises a bridge-head first-span beam, a foam filling structure and a semi-rigid backing plate; the bridge-head first-span beam comprises a planar section and a sloping section connected with the planar section, the bottom of the sloping section is arranged on the upper surface of the abutment and is connected with the coping of the abutment; the abutment and the opposite side of the bridge-head first-span beam are provided with a roadbed; the foam filling structure is filled on the sloping section, the upper surface of the foam filling structure is in the same plane with the upper surface of the roadbed; and the semi-rigid backing plate is fixedly laid on the foam filling structure and the roadbed. The deformation characteristics of the foam filling structure under the load are utilized to make the bridge-head pavement paving layer produce a cooperative settlement deformation with the bridge-head roadbed soil, so that the differential settlement problem between the bridge and the road causing the bridge-head bumping is fundamentally solved, and the phenomenon of bridge-head bumping does not occur in long-term use.

The utility model discloses a portable roadbed compactness rapid detection device which comprises a mobile base, a storage battery is arranged on the upper portion of the mobile base, an electronic scale is installed at the top end of the mobile base, the electronic scale is electrically connected with the storage battery, a bearing rod is arranged on one side of the mobile base, an electric push rod is arranged at the top end of the bearing rod, and the electric push rod is electrically connected with the storage battery. The output end of the electric push rod is connected with a gland, the gland is detachably connected with the electric push rod, and a cutting ring is arranged at the bottom end of the gland. The front end of the movable base is rotationally connected with a pull rod. The storage battery is arranged on the movable base, the electronic scale is mounted at the top of the storage battery, a soil sample can be weighed through the electronic scale, the bearing rod is arranged on one side of the movable base, the electric push rod is arranged at the top of the bearing rod, and the electric push rod can drive the cutting ring to be pressed into a roadbed, so that the cutting ring can be conveniently and quickly inserted into the roadbed; the roadbed soil can be conveniently sampled, and the sampled soil can be directly placed on an electronic scale to be weighed.

The utility model relates to the technical field of roadbed lime soil stirring, in particular to an expressway roadbed lime soil uniform stirring device which comprises a supporting frame, a mixing mechanism is installed on the upper surface of the supporting frame, a smashing mechanism is installed on the upper surface of the mixing mechanism, and a feeding mechanism is arranged on the rear side of the supporting frame. The mixing mechanism comprises a mixing barrel fixedly connected to the upper surface of the supporting frame, the bottom of the interior of the mixing barrel is in the shape of two arcs, and two mixing paddles matched with the bottom of the mixing barrel are rotationally connected to the interior of the mixing barrel. The materials are conveyed to the crushing box through a guide hopper, at the moment, the materials are crushed through rotation of a plurality of crushing shafts and first crushing teeth under the action of second crushing teeth, the crushed materials enter the mixing barrel, at the moment, the materials are stirred under the action of two mixing paddles, and the stirred materials are discharged through a discharging valve.

The utility model discloses a roadbed earthwork filling thickness controller, relates to the technical field of earthwork filling, and comprises a vertical pipe, a vertical rod is inserted in the top of the vertical pipe, an adjusting assembly and a storage assembly are arranged on the vertical rod, the adjusting assembly comprises a limiting pipe arranged on the surface of the vertical pipe in a sleeving mode, a threaded rod is inserted in one side of the limiting pipe, and the storage assembly is arranged on the other side of the limiting pipe. One end of the threaded rod makes contact with one side of the vertical pipe, strip-shaped grooves are formed in the two sides of the inner wall of the vertical pipe, clamping grooves are formed in one sides of the strip-shaped grooves, limiting grooves are formed in the inner bottom walls of the clamping grooves, limiting blocks are fixedly installed on the two sides of the vertical rod, and limiting rods are fixedly installed at the bottoms of the limiting blocks. The roadbed earthwork filling thickness controller is provided with the adjusting assembly and the storage assembly, the longitudinal height and the transverse size of the controller can be adjusted in the using process, meanwhile, the controller can be stored and folded conveniently, operation of workers is facilitated, and working efficiency is improved. And the use convenience of the controller is improved.

The invention relates to the technical field of fabricated roads, in particular to a modular box beam and slab structure unbonded prestress fabricated road and a construction method. The method comprises the following steps of: constructing a longitudinal and transverse lattice beam net by positioning pile distribution road line type and elevation, connecting longitudinal and transverse prefabricated component angle steel, crosswise arranging unbonded prestressed tendons, designing inverted laminated slab multi-situation nodes, secondarily grouting low-shrinkage micro-expansion high-strength grouting materials, and reinforcing structural integrity and settling adjustment by a cast-in-place concrete conversion section. According to the technical scheme, the multi-lattice modular box-type beam and slab bearing system is finally formed. The modular box beam and slab structure fabricated road technical system is more suitable for the conditions that the original bearing capacity of a roadbed soil layer is poor, the roadbed soil layer is seriously eroded by underground water, the geological environment is severe and the like, and the high efficiency of road construction, the integrity of structural bearing and the effectiveness of resisting differential settlement of a roadbed can be better achieved.

The invention provides a grouting test device for simulating an indoor filled roadbed and a test method thereof, and relates to the technical field of grouting tests.The grouting test device comprises a test grouting structure, a soil displacement monitoring structure and a grout manufacturing and conveying structure, and the test grouting structure is used for conducting a grouting test; the soil displacement monitoring structure is used for monitoring and acquiring grouting test data, and the grouting test data comprises roadbed soil layer displacement change data, grouting pressure data and slurry flow data in the grouting process; the grout manufacturing and conveying structure is used for manufacturing grout and conveying the grout to the test grouting structure. By monitoring the displacement of the soil body in real time and dynamically adjusting the grouting parameters, the uniformity and the control precision of the grouting effect are remarkably improved, the grouting pressure and the grouting flow can be accurately adjusted in the grouting process, and accurate reinforcement of different roadbed soil bodies is ensured.

The invention relates to the field of roadbed soil treatment, in particular to a roadbed in-situ soil high-performance ecological reinforcing agent, a preparation method and a construction method, and the reinforcing agent comprises the following raw materials in percentage by mass: 45-85% of sulphoaluminate cement; 8%-25% of Portland cement; 3%-5% of quick lime; 0%-15% of fly ash; 0%-8% of silica fume; 0-15% of superfine slag powder; 3%-5% of sodium sulfate; 0%-2% of sodium silicate; 0%-0.8% of lithium carbonate; 0%-1.5% of a polymer reinforcing agent; 0%-1.5% of organic silicon powder; and 0.1%-0.3% of sodium lignin sulfonate. The reinforcing agent effectively combines the advantages of sulphoaluminate cement and Portland cement, combines other components, has the characteristics of rapid coagulation, rapid early strength development and the like, can regulate and control the soil strength, meets the requirements on compressive strength and durability in engineering construction, shortens the construction period and reduces the construction cost. And the requirement of 4-6h rapid traffic under an emergency repair scene is met.

The invention relates to the technical field of railway roadbed engineering, and provides a heavy haul railway layered unsaturated roadbed working area depth determination method and system, and the method comprises the steps: obtaining a roadbed soil plastic strain function model containing temperature, stress and saturation through a dynamic triaxial test; the method comprises the following steps: establishing a three-dimensional train-track-roadbed coupling finite element model to carry out numerical simulation based on parameters such as train load, environment and roadbed ballast characteristics, extracting the maximum deviatoric stress and deformation of each depth layer, respectively converting the maximum deviatoric stress and deformation into dimensionless strain influence factors and deformation influence factors, and drawing a relation chart corresponding to roadbed depth; and obtaining a corresponding depth value through chart query, and determining the depth of the working area by taking the maximum value after verification. The method solves the problems that an existing method is insufficient in adaptation to high-speed large axle load, the environmental coupling effect is not considered completely, classification adaptability is lacked, and the depth determination accuracy is low, and efficient and accurate determination of the working area depth of the layered unsaturated roadbed of the heavy haul railway of different grades is achieved.

The utility model relates to the technical field of road construction, in particular to a road subgrade lower spring opening treatment structure. According to the spring opening treatment structure, upper and lower layers of longitudinal water seepage blind pipes are arranged on blind ditch sections corresponding to spring openings, spring opening water is collected by the water seepage blind pipes and then converged into a collecting pipe, and then the water is drained out of a road roadbed through the collecting pipe and finally drained into a roadside drainage system; composite geomembranes are arranged at the bottom of an excavation area of a blind ditch section and on the roadbed side close to a road and used for blocking contact between roadside spring opening water and a soil layer on the lower portion of a roadbed, and spring opening water seepage is prevented from damaging a roadbed soil body and affecting the roadbed strength; the pebble layer is backfilled on the waterproof layer, the permeable geotextile is arranged to form the permeable layer, it is guaranteed that seepage water can be smoothly collected and discharged, meanwhile, the pebble layer has the effects of sealing and pressing spring holes and improving strength, and finally the purposes of water drainage and pressure relief are achieved.

The utility model discloses a municipal afforesting road with assembled water-permeable pavement structure relates to building structure technical field, and the utility model discloses a roadbed soil layer is equipped with water-permeable afforesting road on the upper portion of roadbed soil layer for the quick laying and the discharge of precipitation of quick road, and the water-permeable afforesting road includes: water-permeable main road includes the broken stone cushion layer of laying on the upper surface middle part of roadbed soil layer, and the water-permeable main road of the application is formed by the staggered insertion of water-permeable precast brick (spliced building block), and the water channel in the middle part of building block and the water storage tank in fixed building block are mutually penetrated, form efficient catchment system to greatly improve the drainage capacity of road surface, effectively prevent waterlogging, and through the vertical insertion from the top of fixed building block and with the locking of both side building blocks, form the powerful transverse limit, and the dispersed building block is connected into the whole, and the structural stability and the anti -displacement ability of road surface are enhanced significantly, and the service life is prolonged.

Disclosed are geotextiles configured for moisture management. In exemplary embodiments, a geotextile comprises a plurality of structural elements including one or more yarns, cords, or filament bundles arranged to form a fabric or grid. At least a portion of the structural elements include capillary-active surfaces and / or are configured to promote capillary wicking of moisture along at least one direction of the geotextile. At least a portion of the structural elements include internal void regions configured to maintain hydraulic conductivity under compaction. The geotextile is operable for providing dual-mode moisture transport through both capillary wicking and hydraulic flow thereby allowing for removal and redistribution of water from pavement layers and subgrade soils.

The invention relates to the technical field of civil engineering materials, and particularly discloses a large-dosage undisturbed phosphogypsum curing material for a roadbed and a preparation method of the large-dosage undisturbed phosphogypsum curing material. The curing material is prepared from the following components in percentage by mass: 40-60% of undisturbed phosphogypsum, 10-50% of slag, 10-30% of ordinary Portland cement and optional nano micro powder which accounts for 0-5% of the total mass of the three materials. Through scientific proportion design, a large amount of industrial byproduct ardealite is successfully recycled, and the defects that the ardealite is poor in water stability and easy to swell are overcome. After being mixed with soil, the material can generate a series of physical and chemical reactions to generate a gelling body with strength and effectively control volume change, so that the mechanical property and long-term stability of subgrade soil are remarkably improved. The invention not only provides a new way for the bulk consumption of phosphogypsum, but also reduces the dependence of roadbed engineering on traditional cement and lime, and has remarkable economic benefit and environmental protection value.

The application relates to the technical field of bridge and culvert construction, and discloses a bridge and culvert lengthening side line protection structure and a construction method, which comprises an existing box-type bridge wing wall, the roadbed soil side of the existing box-type bridge wing wall 1 is provided with an advanced small guide pipe, an installation groove is arranged on the existing box-type bridge wing wall, a corrugated steel plate retaining wall is fixedly installed in the installation groove, a plugging steel plate is fixedly connected to one end of the bottom of the installation groove, and the plugging steel plate and the bottom of the installation groove jointly form an anchoring cavity; the seamless line does not need to be cut, the corrugated steel plate retaining wall is used to replace the existing wing wall part cut by a rope saw, the effective support of the roadbed filling is realized, the support of the roadbed soil free surface formed after the existing wing wall is cut is realized, the construction safety of the lengthened box-type bridge and the operation safety of the line are ensured, the operation of the existing line is not affected, and the defects of long construction period, large investment and speed limit operation requirement of the existing line are overcome.

The utility model discloses roadbed earthwork filling equipment with an anti-blocking function, which belongs to the technical field of roadbed filling equipment and comprises a support frame, the upper end of the support frame is fixedly connected with a mixing bin, and the upper end of the mixing bin is rotatably connected with a top cover for preventing materials from splashing. In the using process of the device, when materials are clamped in the discharging pipe, namely stones in the materials are clamped between the discharging pipe and the spiral blades, along with rotation of the driving motor, the multiple feeding rollers can move under the counter-acting force of the stones, at the moment, the two feeding rollers can be separated, and the stones in the materials can be separated from the discharging pipe. During the separation process of the two feeding rollers, the guide rods inserted into the corresponding grooves are subjected to the force of separating from the corresponding grooves, at the moment, the spiral blades displace so as to relieve the material clamping state, and when feeding is recovered, the two adjacent feeding rollers are reset under the action of the pulling springs, so that the material clamping state is relieved. In this way, the materials can be prevented from being clamped in the discharging pipe all the time to affect the construction efficiency.

The utility model relates to a sampling device, specifically disclose a kind of roadbed soil sample collection device, including the outer tube of vertical arrangement, the inner tube of being attached to the inner wall of outer tube, the drill rod in inner tube, the spiral drill bit of being equipped in the lower end of drill rod, the sleeve of being set in the outer wall of drill rod, multiple horizontal connection rope of being equipped in the outer wall of sleeve, and to drive the driving device of drill rod rotation;Sleeve is equipped above drill bit, and the end of connection rope away from sleeve is fixedly connected with inner tube inner wall, and multiple connection rope is distributed with the axis of drill rod as the center of circle;Inner tube lower end portion is located above drill bit.The roadbed soil sample collection device of the utility model can complete soil base sampling after drilling is finished, and does not need to collect soil sample from the drilling hole again, and can effectively improve sampling efficiency.

The application discloses a kind of considering nonlinear subgrade soil resilience modulus estimation method and estimation method, comprising: obtaining measured data under different compaction degree, moisture content and stress state by oedometer;According to the influence law of experimental result analysis normal stress, compaction degree and moisture content factor pair, determine the relationship with normal stress, compaction degree and moisture content respectively;The estimation model is constructed as the function of exponential form with physical constraint, and the model parameters in the estimation model are expressed as the polynomial of compaction degree and moisture content;Based on the estimation model, the static octahedral shear stress is calculated, so as to calculate the resilience modulus of subgrade soil.The application takes normal stress as the core and considers physical state, constructs the static soil pressure coefficient estimation model with clear physical meaning, measurable engineering parameters, and can be directly embedded into roadbed dynamic response analysis, and is used for subgrade soil resilience modulus estimation, simple, fast, improves calculation efficiency and accuracy.

The application discloses a kind of based on roadbed soil viscoelastic plastic mechanics model roadbed structure permanent deformation calculation method, the calculation method includes the following steps: determining cycle loading times N, state variable, load characteristic, road surface property;Based on cycle loading times N, state variable, load characteristic, road surface property, using roadbed structure permanent deformation maximum value calculation formula, roadbed structure permanent deformation maximum value calculation is carried out.The fitting process of roadbed structure permanent deformation maximum value calculation formula is: determining the size of calculation condition and road finite element simulation model;Based on the viscoelastic plastic mechanics model of roadbed soil, the finite element calculation of roadbed structure permanent deformation is carried out;Based on the finite element calculation result of roadbed structure permanent deformation under different conditions, determine the influence factor of roadbed structure permanent deformation and corresponding roadbed structure permanent deformation evolution law;Based on the evolution law, the roadbed structure permanent deformation maximum value calculation formula is fitted.The calculation efficiency and accuracy are improved.

The utility model belongs to the roadbed soil body deformation modulus detection technical field relates to a kind of roadbed soil body deformation modulus in-situ detection device.The device includes bearing plate, jack, support frame, contact arm;Bearing plate bottom surface is crimped on the roadbed to be measured, and the top surface is protruded with force column, and strain gauge is pasted on the lateral wall of force column;The force end of jack is contacted with the top end of force column, to load and unload to bearing plate by force column;Support frame is set on the flat ground outside the roadbed to be measured not to be disturbed;Contact arm is across above support frame, and contact arm middle part is rotatably connected with support frame, and contact arm one end is equipped with measuring head, and measuring head is pressed on the top surface of bearing plate, and other end is equipped with micrometer;When jack loads and unloads to bearing plate, the settlement of bearing plate is obtained using micrometer, and the normal average stress of bearing plate is obtained using strain gauge.The utility model realizes the in-situ detection of the deformation modulus of the roadbed soil body to be measured under actual construction scene, and improves detection accuracy.

The application discloses a kind of detection methods of subgrade compactness, comprising: extracting soil sample from the construction site to be measured, it is divided into multiple indoor soil sample samples according to moisture content size;Detect the moisture content and dry density of each indoor soil sample sample, draw relationship curve I;According to the method that steel ball free fall impacts the top surface of soil sample sample, obtain the depth value of each indoor soil sample sample hemispherical pit, establish fitting relationship;Randomly select a point in the subgrade to be detected area as the test point of outdoor subgrade soil moisture content and dry density, obtain the moisture content and dry density of measured subgrade soil sample;According to the steel ball impact method, obtain the depth value of each detection point hemispherical pit in the subgrade to be detected area;Finally, the subgrade compactness of each detection point is fitted to obtain.The application can quickly and directly obtain the subgrade compactness, the detection period is short, the detection efficiency is high, the detection result has high reliability and accuracy, can meet the large-scale large-area continuous filling construction requirement of subgrade.

The invention discloses a saline soil roadbed slope heat preservation and reinforcement structure under freezing and thawing circulation, and relates to the technical field of slope reinforcement. The road comprises a roadbed and a road surface, reinforcing side slopes are arranged at the edges of the roadbed and the road surface, waterproof cloth is laid on the surfaces of the reinforcing side slopes, a drainage layer is laid on the waterproof cloth, and a heat preservation layer is arranged on the surface of the drainage layer. The surface of the drainage layer is covered with the heat preservation layer, heat exchange between external cold air and roadbed soil is blocked through the low heat conductivity of the heat preservation layer, the freezing depth is reduced, the reinforcing layer is poured on the surface of the heat preservation layer, the overall structural strength and the anti-scouring capacity are provided, and the fixing anchor rods penetrate through the reinforcing layer, the heat preservation layer, the drainage layer, the waterproof cloth and the reinforcing slope from top to bottom; the whole composite structure is anchored into a whole, slippage is prevented, and the monitoring and heating mechanism is arranged in the reinforcing layer and is responsible for collecting temperature data, conducting active heating when needed and maintaining the soil body temperature of a reinforcing slope and a road surface to be above the freezing point.

The utility model discloses a kind of roadbed anti-frost heaving structures for filling and digging transition section belong to roadbed anti-frost heaving technical field, the roadbed anti-frost heaving structure includes in vertical direction, from top to bottom sequentially arranged pavement structure layer, first medium coarse sand layer, heat insulation layer and second medium coarse sand layer;The heat insulation performance of heat insulation layer can significantly reduce the influence of external low temperature on roadbed soil, reduce the occurrence of soil frost heaving, ensure the flatness and stability of road.The first medium coarse sand layer and the second medium coarse sand layer have good water permeability, improve the drainage performance of roadbed, can promptly discharge moisture in soil, further reduce the risk of frost heaving.Through preventing roadbed frost heaving, reduce the occurrence of pavement disease, thereby prolong the service life of road, reduce maintenance cost, while the construction process of roadbed anti-frost heaving structure is relatively simple, does not need complex equipment and technology, reduces construction difficulty and cost.

The invention discloses a roadbed soil rebound modulus estimation method considering nonlinearity. The roadbed soil rebound modulus estimation method comprises the following steps: acquiring actually measured data under different compaction degrees, moisture contents and stress states through a consolidation apparatus; analyzing influence rules of factors of normal stress, compactness and moisture content according to experimental results, and determining relationships with the normal stress, the compactness and the moisture content; constructing the pre-estimation model into a function in an exponential form with physical constraints, and expressing model parameters in the pre-estimation model as polynomials of compactness and water content; and calculating static octahedron shear stress based on the pre-estimation model so as to calculate the rebound modulus of the subgrade soil. According to the method, the normal stress is taken as the core, the physical property state is considered, the static soil pressure coefficient estimation model which is clear in physical significance, measurable in engineering parameters and capable of being directly embedded into roadbed dynamic response analysis is constructed, the model is used for estimating the roadbed soil rebound modulus, the method is simple and rapid, and the calculation efficiency and accuracy are improved.

This invention discloses a method for applying a metal strip multi-point displacement sensor in a roadbed settlement model test, comprising the following steps: Step 1: Soil compaction test: The purpose of determining the optimal moisture content and maximum dry density in the soil compaction test is to detect parameters such as roadbed compaction degree and strength, which plays a very important role in improving the quality of roadbed construction. In this invention, when the roadbed soil undergoes settlement deformation, it causes a change in the fiber Bragg grating of the metal strip multi-point displacement sensor. The demodulator analyzes the drift of the reflected light wavelength of the fiber Bragg grating, and the settlement displacement at multiple points of the sensor can be calculated simultaneously. This solves the problem of objectively and accurately measuring the internal soil settlement deformation in roadbed settlement model tests.

The utility model relates to the technical field of civil engineering equipment, in particular to high liquid limit soil roadbed reinforcing equipment which comprises a main body which is integrally arranged in an inclined mode, the two sides of the main body are in butt joint with a driving device through a connecting part, the upper end of the main body is in butt joint with a storage box, and a plurality of discharging grooves are formed in the storage box at equal intervals. A plurality of grooving assemblies are arranged at the bottom end of the storage box at equal intervals, the bottom end of the discharging groove is correspondingly arranged above the grooving assemblies, and a modifying agent is scattered into grooves formed in the grooving assemblies. The soil is turned up through the turning assembly, the flattening assembly is used for flattening the turned-up soil, the grooving assembly is provided with the multiple densely-arranged grooving pieces, the modifier can be evenly mixed into the roadbed soil, and the efficiency of the high-liquid-limit soil roadbed reinforcing operation is improved.

The utility model discloses a subgrade anti-settlement structure, and relates to the technical field of subgrade construction. Comprising a roadbed layer, a waterproof layer, an outer wall top fixedly arranged on the roadbed layer, a drainage layer, an outer wall top fixedly arranged on the waterproof layer and an anti-sedimentation mechanism arranged on the drainage layer, the anti-sedimentation mechanism comprises a plurality of supporting steel rods and anti-sedimentation parts, and the supporting steel rods are fixedly embedded in the outer wall top of the roadbed layer. According to the roadbed anti-sedimentation structure, through the anti-sedimentation mechanism, the overall rigidity of the roadbed can be enhanced, the upper load can be effectively dispersed, sedimentation caused by too large local pressure can be reduced, through the waterproof layer on the roadbed layer, direct contact between water sources such as rainwater and underground water and the roadbed layer can be isolated, and erosion and softening effects of water on the roadbed layer are avoided; surface water is quickly drained through the drainage layer, so that the damage of the surface water to a roadbed layer and a pavement is reduced, and the problems that roadbed soil is excessively softened and the bearing capacity is reduced are solved.