10 results about "Maximum dry density" patented technology

The application discloses a kind of building solid waste-red clay mixed roadbed filler permanent deformation estimation model and modeling, estimation method, the maximum dry density, optimum moisture content and CBR value of building solid waste-red clay mixed roadbed filler under different building solid waste incorporation rate are determined by compaction test, California bearing ratio test;Prepare the building solid waste-red clay sample of different building solid waste incorporation rate, carry out dry-wet cycle test to it, carry out triaxial test to the sample after preset dry-wet cycle number, determine its resilience modulus and permanent deformation;Establish the elastic deformation increment estimation model considering building solid waste incorporation rate, dry-wet cycle number comprehensively, and then obtain the permanent deformation estimation model considering stress-strain relationship, physical state, cycle loading number, building solid waste incorporation rate, dry-wet cycle number comprehensively, then the permanent deformation of building solid waste-red clay mixed roadbed filler is accurately and quickly estimated using the permanent deformation estimation model.

The application discloses a method for treating and utilizing large-particle waste sand in ammonia-alkali method alkali waste liquid, and the process is as follows: treating the large-particle waste sand, reducing the content of soluble salt in the waste sand through water washing, controlling the content of soluble salt in the waste sand to be less than or equal to 2%, designing the mixing proportion of the waste sand lime cement soil, replacing the soil in the cement lime soil with different amounts of waste sand, keeping the mass ratio of the admixture lime and cement unchanged in each test, and decreasing the content of the soil corresponding to the waste sand proportion gradient; carrying out the compaction test on the materials in each group under different target moisture contents, obtaining the maximum dry density and the optimum moisture content of the sample; determining the waste sand replacement interval of the waste sand lime cement soil meeting the strength and the optimum proportion of the waste sand lime cement soil material; and preparing the waste sand lime cement soil for paving the roadbed or the base of the road. The application solves the phenomenon of pipe grinding in the process of filling the well with the alkali waste liquid, prepares the road material according to the designed proportion of the large-particle waste sand and the lime soil, reduces the cost of the alkali waste liquid, and changes the large-particle waste sand into the road raw material.

The application relates to the technical field of fertilizer groove backfilling, and particularly discloses a fertilizer groove backfilling construction method based on MICP technology. The fertilizer groove backfilling construction method based on MICP technology comprises the following steps: soil property determination: determining the maximum dry density p dmax of the soil, the optimal water content w, preparing a microbial slurry and a cementing solution, preparing backfill soil by adding the cementing solution into the soil, backfill construction: backfilling the fertilizer groove with the backfill soil by 300-400 mm, then spraying the microbial slurry on the surface of the backfill soil, continuing to backfill the fertilizer groove and spraying the microbial slurry after the microbial slurry penetrates to the bottom of the backfill soil, and repeating the above operation until the fertilizer groove is backfilled completely. The fertilizer groove backfilling construction method based on MICP technology has the advantages of low construction cost, simple construction method and high backfill compactness.

This invention relates to the field of foundation construction technology, specifically to a construction method for treating thick, collapsible loess foundations, comprising the following steps: Step 1, construction preparation, including determining the natural moisture content, maximum dry density, and optimum moisture content of the foundation soil and backfill soil, and simultaneously watering and mixing the backfill soil for material preparation; Step 2, drilling humidification holes, injecting filter material into each humidification hole after drilling, and then tamping and backfilling; Step 4, after tamping and backfilling, leveling the construction site, watering and moistening it, and after the piles are formed in the pile holes, leveling and fully tamping; Step 5, inspection. The treatment method provided by this invention has a better effect in eliminating collapsibility, resulting in higher foundation bearing capacity, more uniform overall stiffness, smaller settlement deformation, and an effectively shortened construction period, forming a high-bearing-capacity composite foundation.

A system for evaluating the strength improvement of the roadbed through bamboo fiber reinforcement, consisting of: a) a material processing unit for producing a soil-bamboo fiber mixture, wherein the bamboo fibers are selected from the group consisting of Barak (Bambusa balcooa), Bari (Bambusa polymorpha), and Mritinga (Bambusa tulda), wherein the fibers have a length of 1.5 cm and a diameter of 2-3 mm and are incorporated at a rate of 3% of the dry weight of the soil; b) a compaction test facility configured to perform the Standard Proctor compaction test to determine the maximum dry density (MDD) and optimal moisture content (OMC); c) a load-bearing capacity test unit configured to perform CBR (California Bearing Ratio) tests, wherein the test unit is designed for CBR tests in both the impregnated and unimpregnated states; d) a subgrade preparation unit configured to prepare a subgrade test section for roadways, comprising layering and compacting the soil-bamboo fiber mixture in 150 mm thick layers to achieve a subgrade thickness of approximately 600 mm; and e) a deflection measuring unit for performing a falling weight deflectometer (FWD) test, wherein the deflection measuring unit comprises seven geophone sensors arranged at intervals of 0 mm, 300 mm, 600 mm, 900 mm, 1200 mm, 1500 mm and 1800 mm from the center of a load plate, and a load cell configured to apply a load of 40 kN.

The invention discloses a method for accurately determining the rolling dry density of a gravel material through numerical simulation, and provides a method for accurately determining the rolling dry density by performing model simulation by utilizing truncation grading and then compensating a simulation result, so that not only is the operation efficiency of model simulation ensured, but also an accurate simulation result is obtained, and the calculation efficiency is improved. The calculation efficiency and accuracy of determining the dry rolling density of the gravel material through numerical simulation are effectively improved; after the simulation result of the truncation grading is obtained, the pores are compensated through theoretical calculation, the maximum dry density value after compensation is calculated, then the maximum dry density value after compensation is compared with the maximum dry density value of a field rolling test, and the accuracy of the compensation method is verified. According to the method, the gravel material rolling dry density is accurately determined by utilizing numerical simulation, and the calculation precision and the calculation efficiency are both considered.

This invention discloses a method and apparatus for preparing precast piles from engineering waste soil. The waste soil is sieved according to particle size. Based on the particle size composition of the waste soil, particle flow numerical simulation is used to simulate the compaction characteristics of waste soil with different particle sizes under ideal conditions, obtaining the maximum compaction density and gradation. Based on the maximum compaction density gradation under ideal conditions and the characteristic particle size of the cementitious material, different amounts of cementitious material are added to prepare the waste soil mixture. According to the evolution model of compaction density with pressure, the close packing gradation of the waste soil and cementitious material mixture is obtained. Experiments are conducted on the variation of compaction dry density with moisture content, clay mineral content, and cementitious material water demand under different pressure conditions. Based on a multi-parameter artificial neural network machine learning model, a model of dry density with moisture content, clay mineral content, and cementitious material water demand is constructed to obtain the optimal moisture content and maximum dry density under different pressure conditions. A variable frequency micro-amplitude vibration bidirectional compaction device is used for compaction and molding using a four-stage process: static pressure-strong vibration-weak vibration-static pressure.

The invention discloses a preparation method of a remolded sample for reducing in-situ mechanical properties of sandy soil based on a static sounding test. The method comprises the following steps: carrying out the static sounding test to obtain conical tip resistance; calculating the in-situ relative density of the sand through an empirical formula; after drilling sampling, obtaining the maximum dry density, the minimum dry density and the natural water content through an indoor soil test; inversely calculating the in-situ dry density through the in-situ relative density, the maximum dry density and the minimum dry density; calculating the in-situ wet density through the in-situ dry density and the natural water content; and preparing the remolded sample by taking the wet density as a target control index. Compared with the prior art, the static sounding test data and the remolding sample preparation process system are combined for the first time, the target density directly derives from in-situ testing, the in-situ state is scientifically restored, the representativeness is high, operation is easy and convenient, cost is low, and the principle is clear; the process standardization is suitable for various engineering investigation and scientific research projects, is easy to popularize and apply in engineering practice, and is especially suitable for sandy soil environments such as oceans, riverbeds and loose settled layers in which undisturbed samples are difficult to obtain.

The application discloses a kind of rockfill material field maximum dry density determination method and related device considering similar gradation scale effect.The method first obtains field original gradation, determines field maximum particle size, indoor allowable maximum particle size and original over-diameter particle content P1;Similar scale multiple n is set to construct similar gradation curve, and the over-diameter content P2 after scaling is counted;According to whether P2 is greater than 30%, the equivalent coarse particle content P is determined in segments: when P2≤ 30%, P=P2 is taken, when P2> 30%, P=P1 / n is taken;Finally, the maximum dry density obtained by indoor compaction test is converted into field maximum dry density by density conversion formula.The size effect is quantitatively corrected by introducing scale multiple n, the system deviation of indoor test density "virtual height" is eliminated, the calculation precision of rockfill material field maximum dry density is significantly improved, and is suitable for two kinds of scale process of pure similar gradation method and mixed method.

The utility model belongs to the technical field of engineering experiment equipment, and relates to a special test mold for testing the maximum dry density of an aeolian sand roadbed constructed by a water sinking method, which consists of a steel mold lantern ring, a steel mold inner cylinder, a water-permeable small hole, a steel mold outer cylinder, a steel mold bottom plate, a cushion block in a barrel, a fixed frame, a fastening bolt, a water outlet and a water drainage switch. According to the test mold special for testing the maximum dry density of the aeolian sand roadbed constructed by the water sedimentation method, water in an aeolian sand sample subjected to water sedimentation can be timely discharged in a vibration compaction experiment, and the discharged water is reserved in a cavity between the inner cylinder and the outer cylinder, so that the discharged water is effectively prevented from flowing into a test bed from the bottom of the test mold; after the test is finished, water can be discharged from the water outlet through the water discharge switch; the drainage switch is in threaded connection with the drainage port, is of a detachable structure and can be replaced; the structure is simple, manufacturing cost is low, and use and operation are convenient and reliable.