42 results about "Unconfined compression" patented technology

The invention discloses a crack resistance type cement stabilized macadam proportioning design method based on vibration test method. The design method is implemented according to the following steps:(1) preparing framework dense graded aggregate; (2) adding cement into graded aggregate to obtain a cement stabilized macadam mixture, and adopting vibration compaction test method to determine the maximal dry density and the optimal water content of the cement stabilized macadam mixture, wherein the added cement dosage accounts for 3-5% of the graded aggregate according to mass percent; (3) adopting the cement stabilized macadam mixture in step (2) and vibration compaction test method to prepare a cement stabilized macadam cylinder test piece with the dimension being 15cm in diameter * 15cmin height; (4) carrying out an unconfined compression strength test on the cement stabilized macadam cylinder test piece which is subject to 6 days of preserving and 1 day of water soaking, and designing the cement dosage according to the result of the unconfined compression strength test. The cement stabilized macadam designed by the invention can better form a compact framework structure, featuring unlikely dissociation, the maximal dry density, the optimal water content and saving of 30-40% cement use amount, has the advantages of high strength, good crack resistance and good scour resistance, and basically solves the problems of serious crack of cement stabilized macadam which perplexes road engineering circles, at home and abroad, all the time.

The invention belongs to a treatment method of solid waste in environmental engineering, and particularly relates to a method for curing lake dredged sediment containing heavy metal. The method is characterized by comprising the steps of adding a curing agent prepared from waste gypsum, coal ash and cement in a mixing manner to lake dredged sediment containing heavy metal, evenly stirring, and covering a plastic film on the surface for molding for 1-3 days; and maintaining for 2-10 days under the conditions that the temperature is 20+ / -(3-6) DEG C and the relative humidity is 70-100% to obtain a solidified clod of which the unconfined compression strength is greater than or equal to 170.6kpa, wherein the weight ratio of the waste gypsum to the coal ash to the cement is 1 to (0.5-10) to (1-15); and the adding amount of the curing agent is 3-20% of mass of the lake dredged sediment containing the heavy metal. Industrial wastes such as the coal ash, the waste gypsum and the like are taken as curing agent materials of heavy metal polluted sediment; and resource utilization of the wastes such as the polluted sediment, the coal ash and the waste gypsum is achieved, so as to achieve the target of treatment of wastes with processes of wastes against one another.

The invention discloses a sandy soil microbe solidification method and apparatus. The solidification method comprises steps of first, preparing high concentration bacteria liquid, second, compounding cementation medium solution, third, injecting the high concentration bacteria liquid and cementation medium solution into sandy oil, and fourth, nursing the sandy soil and molding the same. In the high concentration bacteria liquid preparation step, Pasteur spore sarcina is transplanted into an ammonium salt-yeast base nutrient solution; the PH value of the nutrient solution is adjusted to be about 8.0 to 9.0; the nutrient solution is vibratingly water-bathed for 30 to 40 hours at the temperature of 30 DEG C; then high concentration bacteria liquid with concentration of 0.8 to 1.2x107cells / ml is centrifugally achieved; the cementation medium solution comprises urea-calcium chloride, ammonium chloride, sodium bicarbonate and ammonium salt-yeast base nutrient solution; in the third step, the sandy soil is manufactured into samples with various dry density; two ends of each sample are respectively provided with a plastic block; the external side of the sample is covered with latex film; 15mL high concentration bacteria liquid and 50 to 100mL cementation medium solution are successively injected into the sandy oil via a peristaltic pump; and the samples are placed and nursed in environment with temperature ranging from 22 to 20 DEG C and relative humidity of 95%. With action of microbe solidification, unconfined compression strength can be obviously improved for the sandy soil.

The invention discloses a soft soil curing agent prepared by means of industrial residues. The curing agent is prepared from, by weight, 35-65% of steel slag, 30-50% of mineral waste residues, 10-30% of desulfurization gypsum, 2-6% of sulphoaluminate cement clinker, 2-4% of ordinary portland cement clinker, 2-5% of aluminum dregs and 0-5% of cement. The sum of the weight percentages of all the components is 100%. The soft soil curing agent is prepared by fully utilizing industrial residues of heat-engine plants, steel works and aluminum electrolysis enterprises, unconfined compression strength is high during soft soil foundation reinforcement, waste is recycled, and economic benefits and environmental protection benefits are high.

The invention relates to a vibration-molding-based cement stabilized macadam mixing ratio design method, which comprises the following steps: (1) preparing optimized dense skeleton type graded aggregate; (2) adding cement into the graded aggregate to prepare cement stabilized macadam mixture; (3) vibrating and compacting the cement stabilized macadam mixture, and determining the optimal water content and the maximum dry density of the cement stabilized macadam mixture in mode of a vibration and compaction test; (4), preparing cement stabilized macadam cylindrical test pieces by using a vibration molding test process at a compactness of 98 percent under the determined maximum dry density and the optimal water content; and (5) perform an unconfined compression test on the prepared cement stabilized macadam cylindrical test pieces and determining the dose of the cement according to the result of the unconfined compression test. The cement stabilized macadam mixture designed by the invention has the characteristics of high strength, high crack resistance, convenience for construction and low cost, and an innovation is made in semi-rigid material design on the basis of a material design guiding ideology.

The invention discloses a base material containing fresh semi-hydrated ardealite, quick lime and coal ash for pavement, which can improve the unconfined compression strength of a pavement foundation. The base material belongs to the field of road materials. The base material comprises the following components in percentage by weight: 20-85% of fresh semi-hydrated ardealite, 3-10% of quick lime and 10-75% of red coal ash or brown coal ash. The base material provided by the invention is a semi-rigid pavement base with excellent performance; the used raw materials are mainly industrial side products; when the base material is used as a road material, the difficultly-utilized industrial side products such as the semi-hydrated ardealite can be greatly consumed and utilized, the stockpiled land can be saved, and the cost can be reduced; and the base material is beneficial to protecting natural resources and environments, the construction process is simple and reliable and is suitable for building of bases and subbases of common roads and high-grade roads.

The invention relates to a soil curing agent. The soil curing agent is prepared from the following components in parts by mass: 30 to 100 parts of sulfonated oil, 10 to 40 parts of alkylol amine, 10 to 80 parts of polyol, 0.1 to 0.5 part of polyanionic cellulose and 50 to 100 parts of water. A stabilized soil reagent prepared from the soil curing agent can obtain very good perform indexes including unconfined compression strength, high water stability and the like. Meanwhile, a soil curing agent solution is weakly alkaline so that the soil curing agent is safer to use and the environment protection is facilitated better. The invention further relates to a preparation method of the soil curing agent.

The invention discloses a cover mould device with unconfined compression strength for an inorganic binder and a method. The cover mould device comprises an outer mould and a crosswise detachable inner mould, wherein the inner mould is connected with the interior of the outer mould in a matching manner, and upper and lower pressing cushion blocks are respectively arranged above and below the interior of the inner mould. The cover mould device is used for overcoming the defect that a tested piece and the inner wall of a tested mould are subjected to jacking, pushing and frictional disturbance during a de-molding process of the tested piece in the prior art. After the tested piece is kept for several days before being soaked in water for fostering, the inner mould is detached crosswise, so that the disturbance of the tested piece is reduced and the practical intensity of the tested piece is effectively ensured.

A control method of construction quality of deep mixing piles based on energy consumption monitoring belongs to the technical field of constructional engineering and is characterized by obtaining the best construction parameters and implementing mixing at the site through geologic survey of the construction site, an indoor mixing test, an indoor model pile test and an unconfined compression test. Compared with the prior art, the method can be used for controlling the construction quality of the deep mixing piles more reasonably.

The invention discloses normal-temperature weak-alkali geopolymer excited cement soil and a preparation method thereof. The cement soil is prepared from an alkali-excited gelling material and clay; wherein the alkali-excited gelling material comprises an active agent and an exciting agent; and taking the clay as reference, the mixing amount of the active agent is 6 to 12 percent and the mixing amount of the exciting agent is 3 to 11 percent. The normal-temperature weak-alkali geopolymer excited cement soil is formed by taking clay as the main raw material, mixing with the active agent and theexciting agent in a dry mixing way and adding water to completely mix, wherein the strength of the mixing initial period is low and the setting time is moderate. The uniaxial compressive strength of the cement soil is measured through an unconfined compression test; and the test indicates that when the mixing amount ratio of the alkali-excited gelling material to the clay is approximately 1:5 andthe mixing amount ratio of the active agent to the exciting agent is 2:1, the mass ratio of components in the exciting agent is 1:1 and the compressive strength of the cement soil is optimal. Throughcomparison, it is found that the uniaxial compressive strength of the mixed material is 2 times that of a pure clay test sample and is 1.5 times that of a limestone soil test sample, and good application prospect in roadbed construction is achieved.

The invention provides a method for determining the wear loss of a composite stratum shield hob. The method comprises the steps of step 1, determining stratum distribution situation along a tunnel planning line and stratum strength S of each stratum by adopting a drilling method and a unconfined compression test; step 2, collecting shield parameters and stratum parameters during the constructionprocess, and determining the dynamic load coefficient nd and the friction coefficient alpha of the to-be-predicted hob; step 3, determining the correlation coefficient k between the friction energy and the accumulated wear loss Q of the hob according to the tool change data in the early stage of shield construction; step 4, determining the accumulated wear loss Q according to a prediction model and the number of tunneling rings N, and determining the timing of replacing the hob according to the wear limiting value Q0. By adopting the method, the purposes of achieving reasonable arrangement ofthe timing of warehouse opening and tool changing, reducing the cost of the tool changing, and shortening the construction period can be achieved.

The invention discloses a testing device for the unconfined compression fluid deformation of a solution environmental action rock mass. The testing device is characterized by comprising a corrosion-resistant solution vat, a corrosion-resistant base, a corrosion-resistant press head, fixed bar racks and a press bar, wherein the corrosion-resistant base is fixed at the bottom of the corrosion-resistant solution vat; the fixed bar racks are located at both sides of the corrosion-resistant solution vat, the press bar is arranged on the fixed bar racks, is located right above the corrosion-resistant solution vat and can move up and down along the fixed bar racks; a position on the lower part of the press bar corresponding to the corrosion-resistant base is provided with the corrosion-resistant press head; and when being used, a test piece is soaked in the corrosion-resistant solution vat filled with solution and is put between the corrosion-resistant base and the corrosion-resistant press head, both ends of the press bar are loaded with weights, and simultaneously the upper part of the press bar is connected with a displacement micrometer gauge used for measuring the deformation degree of the test piece. The testing device has simple structure and low cost, so the testing device is especially suitable for extensive popularization in the unconfined compression fluid deformation test of the solution environmental action rock mass.

The invention discloses an unconfined compression test sample preparation device which comprises a barrel formwork, wherein an inner bottom support and an inner pressure head are arranged in the barrel formwork; a goblet-shaped funnel is inserted in the barrel formwork; lifting handles are arranged outside a barrel-shaped storage part; a top plug is arranged in the funnel; a guide rod is arranged on the top plug; the barrel formwork is sleeved by a protective barrel; a guide cylinder is arranged above the protective barrel; vertical guide slots are formed in the side wall of the guide cylinder; a through cover is arranged at the top of the guide cylinder; a guide hole is formed in the center of the through cover; the upper part of the guide rod penetrates through the guide hole; a limiting ring plate protruding outwards is arranged on the guide rod; a spring is clamped and compressed between the through cover and the limiting ring plate; and the lifting handles are inserted in the vertical guide slots. The unconfined compression test sample preparation device can ensure a soil sample is continuously compressed by the top plug in a soil sample exhaust process so that all air in the soil sample is discharged and then a complete and regular high-quality test sample free of external and internal holes and cracks can be obtained. Besides, the unconfined compression test sample preparation device is simple in structure, reliable in performance and simple and convenient to manufacture.

The invention discloses a cement-stabilized base material and a design method thereof. The cement-stabilized base material is prepared from the following ingredients in percentage by weight: 31.5% to58.4% of coal gangue fines, 31.5% to 58.6% of limestone aggregates, 4.1% to 5.4% of cement and the balance of water. The design method comprises the following steps: 1) carrying out chemical and physical mechanical testing on a coal gangue sample so as to remove the risk of harmful impurities; 2) mixing the coal gangue fines with the limestone aggregates for gradation composition design under theprinciple of maximizing the application of the coal gangue fines; 3) selecting a plurality of cement doses, and carrying out compaction testing; 4) determining a cement dose by 7d unconfined compression strength; 5) verifying the composition scheme of the material through cleavage strength testing, and returning to the step 2) if the composition scheme is not met. Compared with full-aggregate-replaced materials, the cement-stabilized base material has the advantages that the coal gangue fines are used for carrying out partial substitution, the strength index can reach base layer standards, resources are saved, the environment is protected, and the cost of the base material is greatly reduced.

At present, unconfined compression tests for solid particle systems are all executed at room temperature, while in actual engineering, many solid particle systems are in high-temperature environments,and a device for measuring compressive strength of the solid particle systems at the high temperature is needed. Therefore, the invention provides a high-temperature unconfined pressure instrument. The high-temperature unconfined pressure instrument comprises a force measuring ring, a scale, a connecting rod, an upper pressing plate, a lower pressing plate, a screw, a pressing frame, a hand wheel, a support frame, a high-temperature electric heating furnace, heating elements, a temperature measuring element, a temperature control device, a furnace wall, a furnace door and a test sample, can perform unconfined compressive strength tests on the solid particle systems at the high temperature and can accurately measure the unconfined compressive strength of the solid particle systems at the high temperature.

The invention discloses a vibration cracking test device under energy control. The device of the invention comprises an unconfined compression strength tester, a test piece, an annular iron hoop for fixing the test piece and a vibration exciting mechanism for vibration output. The vibration exciting mechanism comprises a vibration exciter, a support, a drive screw, a power amplifier and a signal generator. The power amplifier and the signal generator are connected. The signal generator is connected to the power amplifier which is then connected to the vibration exciter. The vibration exciter is fixed on the support. The test piece is arranged on the unconfined compression strength tester. The annular iron loop is arranged at the central position of the test piece and is vertical to the axial direction of the test piece. Two ends of the drive screw are respectively connected to the vibration exciter and the annular iron loop. Through vibration adjustment, a vibration cracking test of coal-rock mass under energy control can be greatly simulated, thus providing researches with reliable basis and data support. Meanwhile, by vibration excitation of the test piece, disturbance influence of mechanical vibration on coal-rock mass during underground mining process can be greatly simulated.

The invention discloses a single-axis test automatic strain measuring device and a method based on computer vision. The device comprises a sample box, an upper pressing plate, a lower pressing plate,a weighing sensor, a displacement sensor, a camera, a light source, a data recorder, a computer, a first support column, a bottom plate, a frame, a working table, a support, a column body, a second support column, a third support column and a connecting column. A driving mechanism is arranged in the working table. The upper pressing plate is connected with the weighing sensor through the connecting column. The lower pressing plate is fixedly connected with the bottom plate. The sample box is arranged between the upper pressing plate and the lower pressing plate. Samples are placed in the sample box. The driving mechanism drives the second support column to perform a vertical lifting motion, so as to drive the lower pressing plate to conduct an uniaxial compression test on the sample in thesample box. According to the single-axis test automatic strain measuring device and the method based on computer vision, the axial strain and the radial strain in an unconfined compression test can be rapidly and accurately measured, and processing is performed in real time, so that a better test means is provided for evaluating the strain characteristic of the unconfined compression strength ina geotechnical engineering.

The invention discloses an enhancing agent for consolidating tailing of iron core, which is composed of 7-12% of sodium methylsilanolate, 8-13% of acetonformaldehyde condensate sulfonate (USZ), 10-25% of NaSO4, 1-5% of succinate sodium, 5-15% of sodium aluminate and 50% of water. The product has no harm to human body, livestock and plants. The soil solidified intensifier has high initial strength, good cracking resistance and freeze resistance, the seven-day unconfined compression strength is larger than or equal to 3.0Mpa, the anti-bending tensile strength is 0.50-0.62Mpa, the modulus of resilience is 1,300-1,700Mpa, and the water stability is 90-95%. The intensifier has less usage and large supply diameter, facilitates construction and can reduce construction cost.

The invention, which belongs to the sample preparation device and a preparation method thereof for civil engineering materials, discloses a sample making device and making method thereof for an unconfined compression test. The sample making device mainly comprises a storage device, a uniform mixing device, a metering device, a sample pressing device and an automatic control device and the like. The device is simple and is convenient to operate; making of samples with different sizes is realized easily and rapidly; and the repeatability is high. Besides, the method includes steps of uniform material mixing, mixed material weighing, assembling of a pressing device, sample compressing, and sample taking out and the like. The made sample has high uniformity; the moisture content and the dry density of the sample can be accurately controlled; accurate compression is realized by one-step hydraulic control; problems that the making pressure is not uniform and the upper-lower layering and density of the sample are not uniform are solved; the yield, uniformity and making efficiency of the sample can be improved to the great extent; and the application range is wide. The making device and making method can be applied to unsaturated soil, contaminated soil and concrete and the like.

The invention discloses a device for determining isotropic electrical properties in a soil body compression process, a sample is arranged between an upper bearing plate and a lower bearing plate, an upper electrode plate and a lower electrode plate are respectively arranged at the top and the bottom of the sample, and an axial displacement sensor and a pressure sensor are arranged at the top of the upper bearing plate; radial electrode plate pairs are arranged at different height positions of the sample, and each radial electrode plate corresponds to one radial displacement meter. The invention further discloses a method for determining the isotropic electrical properties in each direction in the soil body compression process. The sectional area of the test sample at any time can be obtained, a result is corrected, the test accuracy is improved, and the result is more reliable. The internal structure change and the isotropic electrical properties of the soil body in the unconfined compression process can be analyzed more comprehensively through multi-path measurement. Resistivity and displacement changes are synchronous real-time data, so that the continuity of the test and the correlation of the data are improved.

The invention provides a method for determining the wear loss of a composite stratum shield hob. The method comprises the steps of step 1, determining stratum distribution situation along a tunnel planning line and stratum strength S of each stratum by adopting a drilling method and a unconfined compression test; step 2, collecting shield parameters and stratum parameters during the constructionprocess, and determining the dynamic load coefficient nd and the friction coefficient alpha of the to-be-predicted hob; step 3, determining the correlation coefficient k between the friction energy and the accumulated wear loss Q of the hob according to the tool change data in the early stage of shield construction; step 4, determining the accumulated wear loss Q according to a prediction model and the number of tunneling rings N, and determining the timing of replacing the hob according to the wear limiting value Q0. By adopting the method, the purposes of achieving reasonable arrangement ofthe timing of warehouse opening and tool changing, reducing the cost of the tool changing, and shortening the construction period can be achieved.

The invention discloses a cement-stabilizer construction waste recycled mixture and a preparation method thereof. The recycled mixture is prepared from the following raw materials of aggregate, cementand water, wherein the aggregate is prepared from construction waste recycled aggregate and aggregated rock with the specifications as 10 to 30 mm, 10 to 20 mm, 5 to 10 mm and 0 to 5 mm, and the construction waste recycled aggregate comprises bricks and concrete blocks. The unconfined compression strength of the cement-stabilizer construction waste recycled mixture is 6.8 to 8.8 MPa, so that thecement-stabilizer construction waste recycled mixture can meet a requirement of middle and high-grade roads; the construction waste recycled aggregate comprises the determined use amount of the bricksand the concrete blocks; after the construction waste recycled aggregate is mixed with the certain proportion of new aggregate and water, raw material composition and the use amount of the cement-stabilizer construction waste recycled mixture can be clearer and more definite, and the character of the cement-stabilizer construction waste recycled mixture can be stabler; the preparation method of the cement-stabilizer construction waste recycled mixture is simple; furthermore, a use amount ratio of the bricks to the concrete blocks in the construction waste recycled aggregate can be adjusted, the cement-stabilizer construction waste recycled mixture can meet use of different grades of road base materials, and easiness in operation and implementation is achieved.

The invention relates to the technical field of automobile production, and discloses a positioning fixture for flow line production of automobiles. The positioning fixture comprises a worktable, wherein a conveying device is mounted in the middle of a face side of the worktable; driving motors are both mounted on the top and at the bottom of the face side of the worktable; output shafts of the driving motors are fixedly connected with movable plates; back sides of the movable plates are in lap joint with the face side of the worktable; and both grooves are formed in corresponding parts of the opposite sides of the two movable plates. According to the positioning fixture for the flow line production of automobiles disclosed by the invention, through the arrangement of the movable plates, the grooves, springs, fixed sleeves, pressure sensors and positioning clamp plates, the springs can be retracted when components on the conveying device are clamped and positioned, so that the positioning clamp plates are retracted, and automotive parts of different specifications can be adapted, thereby improving the compatibility; meanwhile, the movable rods extend into the fixed sleeves and stop when the movable rods extend to the pressure sensors so as to avoid the damage to the positioning fixture by unlimited compression.

The invention discloses a sandy soil microbe solidification method and apparatus. The solidification method comprises steps of first, preparing high concentration bacteria liquid, second, compounding cementation medium solution, third, injecting the high concentration bacteria liquid and cementation medium solution into sandy oil, and fourth, nursing the sandy soil and molding the same. In the high concentration bacteria liquid preparation step, Pasteur spore sarcina is transplanted into an ammonium salt-yeast base nutrient solution; the PH value of the nutrient solution is adjusted to be about 8.0 to 9.0; the nutrient solution is vibratingly water-bathed for 30 to 40 hours at the temperature of 30 DEG C; then high concentration bacteria liquid with concentration of 0.8 to 1.2x107cells / ml is centrifugally achieved; the cementation medium solution comprises urea-calcium chloride, ammonium chloride, sodium bicarbonate and ammonium salt-yeast base nutrient solution; in the third step, the sandy soil is manufactured into samples with various dry density; two ends of each sample are respectively provided with a plastic block; the external side of the sample is covered with latex film; 15mL high concentration bacteria liquid and 50 to 100mL cementation medium solution are successively injected into the sandy oil via a peristaltic pump; and the samples are placed and nursed in environment with temperature ranging from 22 to 20 DEG C and relative humidity of 95%. With action of microbe solidification, unconfined compression strength can be obviously improved for the sandy soil.

The invention relates to an emulsified asphalt demulsification time testing method based on compression strength. The method comprises the following steps: (1) putting a blended emulsified asphalt mixture into an unconfined compression strength mold; (2) putting an iron block having a constant weight on the emulsified asphalt mixture, respectively curing for 2, 3, 4, 5, 6 and 7 hours, and simulating the state of the emulsified asphalt mixture in a transportation process; (3) demolding the emulsified asphalt mixture cured for the specified time length, and testing the compression strength of the emulsified asphalt mixture by using a universal testing machine (UTM) at a constant loading rate; and (4) comparing the compression strength values of the emulsified asphalt mixture cured for different time lengths, wherein the curing time corresponding to the emulsified asphalt mixture with the largest compression strength is the emulsified asphalt demulsification time.

The present invention adopts a method for improving Shanghai clay with polyvinyl alcohol fibers. The Shanghai clay is taken, air-dried, crushed, passed through a 2mm geosieve, and vibrated and compacted on a vibrating table; the polyvinyl alcohol fibers are weighed, and the polyvinyl alcohol fibers The quality of the clay is 0.2%~1.2% of the quality of Shanghai clay, and the polyvinyl alcohol fibers are dispersed; the polyvinyl alcohol fibers are added in the order of clay-polyvinyl alcohol fibers-stirring evenly, so that the fiber surface of the polyvinyl alcohol fibers is the same as that of Shanghai The contact of clay is the largest; then add water, the moisture content of clay should be controlled between 15% and 25%, after stirring evenly, put the clay into a fresh-keeping bag; then keep the fresh-keeping bag at room temperature for 20-30 hours, and the improved Shanghai clay. The invention utilizes the high elastic modulus, tensile strength and other properties of the polyvinyl alcohol fiber to improve the shear strength, unconfined compressive strength and deformation resistance of the clay, thereby enhancing the engineering properties of the soil.

Provided is a method for predicting the pile-forming strength of the body of a high-pressure jet-grouted pile on the basis of the testing of return grout at a construction site. The method comprises: configuring strength test blocks having different cement dosages, testing the strengths thereof, and drawing an age strength-cement dosage relationship curve; obtaining an EDTA titration standard curve of return grout in the case of different cement dosages by means of trails; sampling cement-soil return grout at a grout return port for a high-pressure jet-grouted pile, and determining the corresponding mass m1 of cement in a quantified cement-soil return grout sample; monitoring a jet grout flow rate Q and a return grout flow rate V2 during on-site construction; obtaining the density of the cement-soil return grout sample; obtaining the mass m2 of the dried cement-soil return grout sample; calculating the mass M6 of cement in a pile body; and calculating the dosage of the cement in the pile body, predicting the unconfined compression strength of the pile body at different ages, and determining whether design requirements are met. The accurate prediction of the age strength of a pile body is realized by means of an age-strength standard curve of test blocks having different cement dosages, which is of significant practical importance for predicting the construction quality of a high-pressure jet-grouted pile.

The invention discloses a method for preparing and detecting a cementation sample of calcareous sand. The method specifically comprises the following steps: mixing cementing materials with the calcareous sand by weight ratio according to the sand quality condition, adding water to the mixture to mix the mixture evenly, and tamping the mixture in a mould to obtain a sample; keeping stand the sample for three days to harden the sample; and taking out the sample, sleeving a rubber membrane on the sample, and putting the sample into a triaxial test machine to perform experiment and obtain the experimental data of unconfined compression strength and the data curve. The method can obtain the influence on the strength of the calcareous sand caused by different cementations through testing the cementation sample of the calcareous sand with various weight ratios and analyzing experimental data, thereby providing a safe and reliable data base for the application of the calcareous sands to engineering.

The utility model provides a device for an unconfined compression-resistant test mold, and belongs to the field of geotechnical test equipment. The problems that an auxiliary loading device for manufacturing the unconfined compression-resistant test piece cannot be suitable for test molds of different sizes, and the material insertion efficiency is low are solved. According to the technical scheme, the pouring device comprises a pouring groove body of a hollow structure, one end of the pouring groove body is detachably connected with a guiding device of a hollow structure, the guiding device is of an integrated structure, and the tangent line of the inner surface of the pouring groove body intersects with the center line of the pouring groove body. The pouring groove body is connected with a fixing device through a plurality of connecting devices, a tamping device is arranged in the fixing device in a clearance fit mode, the tamping device is further in clearance fit with a guiding device, and the fixing device, the pouring groove body and the guiding device are coaxially arranged. The device is applied to soil tests.

The application provides a model test method for simulating progressive weakening of slope strength, and relates to the technical field of geomechanical model test, which comprises the following steps: curing base material to obtain a sample, wherein the sample is a cylinder; selecting a weakening solution by trial method according to a preset model slope evolution time length; performing a weakening test on the model slope by immersing the model slope in the weakening solution; obtaining evolution process information of the model slope, and determining a critical time corresponding to the occurrence of a sliding surface of the model slope; performing a weakening test on the sample by using the weakening solution, and performing an unconfined compression test on the sample when the test time reaches the critical time, so as to obtain the cohesion of the sample; and calculating the critical cohesion of a prototype slope from the cohesion of the sample. In the case that the shear strength of the slope body is insufficient, the strength parameter of the slope body is gradually reduced, and the whole process of the slope body instability evolution is studied.