35 results about "Saturated-surface-dry" patented technology

The invention discloses a method for rapid measurement of material water content and water absorption. Precise weighing and measurement of the gas content A% are carried out on a test material, and then the material water content and water absorption are calculated according to a formula as the following: the material water content and water absorption=(V-VW-A%*V-(Mtest/rho0)/[Mtest*(1/rhoW-1/rho0)]. Specifically, V is the volume of a sealed container, VW is the water volume under a finally water filled state, VW=(M2-M1)/rhoW, A% is the measured gas content, M is the mass of the sealed container, M1 is the mass of the material-loaded sealed container, M2 is the mass of the material-loaded sealed container filled with water, Mtest is the mass of the test material, Mtest=M1-M, rho0 is the density of the material under a saturated surface dry condition, and rhoW is the density of water. If the calculated data is a positive value, the data refers to the water, and if the calculated data is a negative value, the data refers to the water absorption of the test material.

The invention discloses a concrete hollow building block with junked tire rubber granules and a preparation method thereof. The concrete hollow building block is prepared from the following raw materials in parts by weight: 302-375 parts of cement, 565.7-607.2 parts of medium river sand, 1180-1300 parts of gravel and/or rubble, 21.8-59.3 parts of rubber granule, 2.385 parts of water reducing agent and 106-134 parts of water. The preparation method comprises the following steps: immersing the rubber granules in a 20% KOH solution for 20 minutes, cleaning with clear water, and airing to the saturated-surface dry condition; adding the medium river sand, cement, water reducing agent and rubber granules into a stirrer, and stirring; and adding the gravel and/or rubble, adding water, stirring to obtain mixed concrete grout, forming the mixed concrete grout in a forming machine, curing, stripping, and naturally curing. The granularity of the rubber granules is 0.1-5mm, and the size distribution is reasonable. The hollow building block prepared by the method has favorable thermal insulation property, heat insulation property, sound insulation property, light weight and other comprehensive properties, and is suitable to be used as a building load-bearing building block for different load-bearing strength demands.

The invention discloses a grading evaluation system of low-quality recycled aggregates. The grading evaluation system comprises the following steps: (1) carrying out grading evaluation on low-quality recycled aggregates; (2) carrying out grading evaluation on ordinary aggregates; (3) carrying out grading evaluation on mixed aggregates, wherein mixed coarse aggregates are composed of low-quality coarse recycled aggregates and ordinary coarse aggregates; the performance indexes of the mixed coarse aggregates meet the requirements as follows: the crushing value index is less than 30%, the sturdiness is less than 12%, and the water absorption of an hour is less than 3%; mixed fine aggregates are composed of low-quality fine recycled aggregates and ordinary fine aggregates; and the performance indexes of the mixed fine aggregates meet the requirements as follows: the compressive strength rate of 28 days is greater than or equal to 85%, the sturdiness is less than 10%, and the saturated-surface-dried moisture retention is less than 5%. When the low-quality brick recycled aggregates of meeting the grading evaluation indexes disclosed by the invention are applied to recycled aggregate concrete, the recycled aggregate concrete has the advantages of high compressive strength, stable performance and the like, and the problem of recycling of the low-quality recycled aggregates can be effectively solved.

The invention discloses a preparation method of bagasse fiber for asphalt pavement reinforcement. The method comprises the steps as follows: purifying a bagasse material, removing impurities, adding alkali liquor for soaking, taking out bagasse, and adjusting pH to obtain saturated bagasse; adding enzyme to the saturated bagasse for hydrolysis, taking the bagasse to obtain saturated surface dry bagasse; adding a chemical dispersant and an expanded perlite micropowder to the saturated surface dry bagasse, and performing mixing to obtain a mixture; adding water to the mixture and performing mechanical dispersion to obtain a mechanical dispersed substance; drying and screening the mechanical dispersed substance to obtain the bagasse fiber. The bagasse prepared with the preparation method hasthe length of 1-6 mm, the length-diameter ratio of 30-50 and the tensile and breaking strength of 300-600 MPa, and the thermal stability and oil absorbency of the bagasse fiber are good; the bagasse fiber is mixed in an asphalt mixture, the high-temperature stability, low-temperature crack resistance and fatigue crack resistance of the asphalt mixture can be remarkably improved, and the asphalt mixture is low in raw material cost, low-carbon and environmentally friendly.

The invention discloses a measuring device and method for saturated surface dry water absorption of sandstone aggregate. The measuring device comprises a temperature and humidity control box, an automatic collecting and recording device, an upper computer, an electronic balance and a sample disc. A through hole for communicating the interior of the temperature and humidity control box with the outside is formed in the top of the temperature and humidity control box, the sample disc is connected with the electronic balance through a pull rope, the pull rope penetrates through the through hole to hang the sample disc in the temperature and humidity control box, the electronic balance is connected with the automatic collecting and recording device, and the automatic collecting and recording device is connected with the upper computer. The measuring device and method have the advantages that the sand saturated surface dry state can be accurately determined, the automation degree is high, the influence of operators is avoided, and the test result accuracy is high.

The invention discloses lightweight aggregate concrete containing low-quality recycled aggregate. The raw materials of the lightweight aggregate concrete are comprised of cement, coal ash, mineral powder, water, low-quality recycled light-fine aggregate, low-quality recycled light-coarse aggregate, inorganic salt and polrvinyl benzene sulphonate. The raw materials of the lightweight aggregate concrete further comprise additional water consumption. The additional water consumption is represented through the formula of delta W=msr*wsr + mgr*wgr, wherein the msr means consumption of the low-quality recycled light-fine aggregate, the wsr means the saturated-surface-dried water absorption rate of the low-quality recycled light-fine aggregate, the mgr means consumption of the low-quality recycled light-coarse aggregate and wgr means the 1h water absorption rate of the low-quality recycled light-coarse aggregate. According to the lightweight aggregate concrete and the preparing method of the lightweight aggregate concrete, when the low-quality recycled aggregate is applied to preparing of the lightweight aggregate concrete, through adjustment to the raw materials and matching with specific additionally added agents, the additional water consumption targeted to the low-quality recycled aggregate is adopted, so that the mixture state can meet the use requirements, the stable state of the mixture is maintained, cement slurry can be helped to be evenly coated around the aggregate, workability of the concrete mixture is good, and no bleeding and segregation phenomena exist.

The invention discloses a determination method for compression strength ratio of low-quality recycled fine aggregate mixed mortar. The determination method comprises the steps of firstly determining saturated-surface-dry water adsorption of the low-quality recycled fine aggregate and common sand; drying to a constant weight; weighing dried common sand and cement; mixing the dried common sand with the cement; adding water with stirring to obtain mortar until the fluidity of the mortar is (130+/-5) mm; making a benchmark mortar test specimen from the mortar; testing after 28 days of standard curing; recording a strength being f[0] MPa; then mixing the low-quality recycled fine aggregate and the common sand to obtain mixed mortar; weighing the mixed mortar and the cement; mixing the mixed mortar with the cement; adding water in the mixture to prepare a contrast mortar specimen; testing after 28 days of standard curing; and recording a strength being f MPa. The mortar compression strength ratio (delta) after 28 days of standard curing is equal to f/f[0]. The determination method takes additional water consumption while determining the mixed mortar strength ratio, and can actually reflect the performances of the mixed recycled fine aggregate.

The invention relates to the field of concrete, in particular to modified aggregate, a preparation method thereof and concrete applying the modified aggregate. The modified aggregate comprises aggregate and an ionic liquid-like phase change energy storage modifier, and the ionic liquid-like phase change energy storage modifier is located in pores in the surface of the aggregate; and the ionic liquid-like phase change energy storage modifier comprises an ionic liquid-like material with a phase change temperature range of 20-38 DEG C. The preparation method comprises the following steps: dipping: dipping the aggregate in a liquid ionic liquid-like phase change energy storage modifier to enable the ionic liquid-like phase change energy storage modifier to enter gaps of the aggregate, taking out the aggregate, and cooling the aggregate to a saturated surface dry state; slurry wrapping: wrapping the surface of the aggregate in the saturated surface dry state with cement-based slurry, forming a layer of shell, and preparing the modified aggregate. Concrete prepared from the modified aggregate has good heat preservation and energy storage effects, and a concrete product prepared from the modified aggregate has good strength.

The invention relates to a concrete processing method and device for engineering construction. The concrete processing method and device for engineering construction comprise the following steps that S1, mountain sand with the size of 0.3-0.6 mm and mountain sand with the size of 0.8-1.18 mm are screened out to serve as fine aggregate, and pebbles with the size of 5-9.5 mm are screened out to serve as coarse aggregate; and S2, the gravel coarse aggregate screened out in S1 is put into a polishing mechanism to be subjected to surface roughening primary treatment. According to the concrete processing method and device for engineering construction, round and full pebble surfaces can be subjected to roughening treatment for multiple times, dry ice particles and ice particles are adopted for conducting cleaning type polishing treatment on the pebble surfaces in the multiple stirring processes, a certain roughening effect can be achieved while the pebble surfaces are cleaned, and secondary filtering is not needed. Wherein the ice particles permeate into gaps of the pebbles after being melted, so that the pebbles reach a saturated surface dry state, the treated pebbles are mixed with other materials to form the concrete with high flowability and high strength after solidification, and the use effect is relatively good.

The invention discloses internal curing sand for special concrete as well as a preparation method and application of the internal curing sand. The internal curing sand is a core-shell inorganic spherical particle, the particle size of the internal curing sand is 1.0-6.0 mm, the wet bulk density of the internal curing sand in a saturated surface dry state is 800-1200 kg/m <3>, the cylinder compressive strength of the internal curing sand is greater than 6.0 MPa, and the water absorption rate of the internal curing sand is greater than 20%. The internal curing sand is prepared from waste materials, and is small in particle size, high in strength, large in stacking density and high in water absorption rate. The mixing amount of the internal curing sand in special concrete accounts for 10-30%of the use amount of a cementing material, and the internal curing sand can improve workability, reduce bleeding rate, improve pumpability, promote hydration of cement in concrete, significantly reduce self-shrinkage of high-strength concrete, improve expansion rate of expansive concrete, obviously improve crack resistance of the concrete and improve middle and later strength of the concrete. Theinternal curing sand of the invention is especially used for high-strength and ultrahigh-strength concrete, expansive concrete, fair-faced concrete and special structural concrete which is difficult to maintain.

The invention relates to the technical field of machine-made sand, in particular to a tail end process for improving the quality of machine-made sand. The tail end process comprises the following steps of S1, selecting rock blocks; S2, crushing rock blocks; S3, conducting screening; S4, performing dust removal; and S5, obtaining machine-made sand. A sand washer water tank is provided with a watersupply system; and the water supply system comprises a high-water-level liquid level meter, a middle-water-level liquid level meter, a low-water-level liquid level meter, a submerged pump, a sewage pump, a water adding valve and a liquid level controller. A square-hole screen is selected as the screen; the size of each sieve pore is 3.5 to 4.5 mm; the inclination angle of the screen surface is generally about 20 degrees; good screening efficiency and treatment capacity of the materials can be achieved; the water volume in water tank is effectively controlled; the submerged pump is protected; the water is saved; the saturated surface drying effect of the machine-made sand is achieved; the national requirements are met; and the quality of the machine-made sand can be effectively improved, and the performance of machine-made sand concrete is improved through the technical requirements of mine mother rock, the technical requirements of a vibration feeding screen, a material crushing methodand the mechanism of the material crushing method in the machine-made sand production technological process.

The present invention discloses an efficient aggregate saturated surface dry stirring device which comprises a bottom plate, a plurality of supporting columns, a base and a stirring device, and further comprises a material placing device, a heating assembly and a moving device, the material placing device comprises a first rotating rod and a second rotating rod, a placing groove is formed in the upper surface of the base, and a stirring barrel is slidably arranged in the placing groove; one end of the first rotating rod is hinged to one side of the inner wall of the containing groove, one end of the second rotating rod is hinged to the other side of the inner wall of the containing groove, a first T-shaped sliding groove and a second T-shaped sliding groove are formed in the lower surface of the stirring barrel, a first sliding rod fixed to one end of the first rotating rod is slidably arranged in the first T-shaped sliding groove, and a square through groove is formed in one side wall of the T-shaped sliding groove. A square driving rod is slidably arranged in the square through groove, a second sliding rod is slidably arranged in the second T-shaped sliding groove, concave holes are formed in the two ends of the second sliding rod, first springs are fixed in the concave holes, triangular clamping blocks are slidably arranged in the concave holes, and one ends of the first springs are fixed to the triangular clamping blocks. The stirring device has the advantage that stirring raw materials can be conveniently and completely taken out.

The invention discloses a lime-fly ash macadam waste recycling method, which comprises the following steps: (1) screening lime-fly ash macadam waste and natural aggregate, and synthesizing required gradation; (2) soaking the lime-fly ash waste recycled coarse aggregate in water for 24-28 hours, and air-drying free water on the surface to obtain saturated surface dry lime-fly ash waste recycled aggregate; (3) weighing 3.9-7.8 parts of lime-fly ash gravel waste recycled coarse aggregate, 5.2-9.1 parts of natural aggregate and 6.5-7.5 parts of medium sand, and uniformly mixing the components; (4)weighing 0.5-0.7 part of water, pouring into a mixing container, and mixing with the product obtained in the step (3) for 50-60 seconds; (5) adding 2.8-3.6 parts of cement into the mixture obtained in the step (4), and mixing the components for 30-40 seconds; and (6) pouring 0.5-0.8 part of water, continuously mixing the components for 110-120 seconds, and maintaining the mixture to obtain the lime-fly ash gravel waste recycled concrete. According to the lime-fly ash gravel waste recycled concrete prepared by the method, the strength can reach C50, the strength requirements of most concrete components are met, the application limitation of the original lime-fly ash gravel waste is broken through, and the utilization way is broadened.

The invention discloses a quantitative determining device for the saturated surface dry state of fine aggregates and a method thereof. The quantitative determining device is characterized by comprising two back plates, a hopper and a bearing platform. The two back plates are vertically intersected, and the intersection line is vertical. The hopper is fixedly connected with the upper portions of the two back plates. A discharge spout is arranged on the intersection line of the two back plates. The bearing platform is horizontally arranged on the lower portions of the back plates in the mode of being spaced from the bottom faces of the back plates by a certain distance and used for bearing the fine aggregates freely dripping from the discharge spout. The two edges of the bearing platform are fixedly connected with the two back plates respectively, and the circle center is located on the intersection line of the two back plates. The fine aggregates dripping onto the bearing platform from the hopper form a quarter cone gradually, when the radius of the quarter cone is equal to the radius of the bearing platform, the height of the quarter cone is measured, accordingly, the surface state of the fine aggregates at the moment can be represented quantitatively, and then whether the fine aggregates are in the saturated surface dry state is judged.

The invention discloses an integrated device for measuring the apparent density of aggregate. The integrated device comprises a water containing barrel and a mesh basket, wherein a vertical columnar communicating vessel is arranged on the side surface of the water containing barrel, the mesh basket can be placed in the water containing barrel, and scales are arranged on the vertical columnar communicating vessel. The determination method comprises the following steps that an aggregate sample soaked for 24 hours is treated into a saturated surface dry state according to engineering requirements, and the mass of the aggregate is weighed; a net basket is completely immersed in a water containing barrel filled with water, and the water level height is read from a dial gauge of the columnar communicating vessel; all the aggregate samples in the saturated surface dry state are put into a mesh basket and are immersed into a water containing barrel filled with water, and the water level height is read from a dial gauge of the columnar communicating vessel; and the measured aggregate apparent density is calculated according to a formula. Compared with a traditional measuring device and method, the method is novel, the structure is integrated, operation is easy, the requirement for testers is not high, calculation is easy, and efficiency is high.

The invention discloses a method for comprehensively measuring saturated surface dry water absorption of artificial sand, which is characterized by comprising the following steps: 1, taking a certain amount of artificial sand sample, screening the artificial sand sample into an oversize part and an undersize part by using a 0.08 mm sieve, and recording the fractions of the oversize part and the undersize part in the total sample; 2, measuring the oversize part by using a natural sand saturated surface dry water absorption test method; 3, preparing a plurality of stone powder sub-samples with different water contents from the undersize part according to the estimated saturated surface dry water absorption rate, sequentially determining the water contents at equal intervals, and determining the saturated surface dry water absorption rate of the stone powder sub-samples; and 4, multiplying the saturated surface dry water absorption of the oversize part by the fraction of the oversize part, and multiplying the saturated surface dry water absorption of the stone powder by the fraction of the undersize part to obtain the saturated surface dry water absorption of the artificial sand sample. According to the invention, the artificial sand is sieved into the oversize part and the undersize part by the 0.08 mm sieve, the measurement result is accurate, the practicability is strong, and the method can be applied to the field with weaker test conditions, and the data can be output on the field to give the result.

The invention discloses anti-cracking alkali slag recycled concrete and a preparation method thereof. According to the invention, sodium sulfate, sodium silicate and cement are used as composite excitants, such that advantages of cracking resistance, good strength, and the like are provided. The recycled coarse aggregate with the saturated surface dry can return water to achieve an internal curing effect, so that the shrinkage of the material is reduced, and the anti-cracking performance is improved; magnesium oxide is adopted to compensate shrinkage of the alkali slag concrete, and cracking is further reduced; by adopting the PTB emulsion, the development of micro-cracks in the material can be inhibited, and the waterproof performance and the workability are relatively good; and the used slag and recycled aggregate are wastes which are recycled, so that garbage landfill can be reduced, and environmental management and protection are facilitated. The anti-cracking alkali slag recycled concrete has good economic, social and environment-friendly benefits and is suitable for large-scale popularization and application.

The invention provides pavement concrete as well as a preparation method and application thereof, and belongs to the field of comprehensive recycling of waste aerated concrete. As waste aerated concrete recycled fine aggregate is loose and porous and has very strong water absorption, pre-wetted fine aggregate in a saturated surface dry state is obtained by pre-wetting in advance, it can be ensured that the slump is within a reasonable range, and the result shows that the pre-wetted waste aerated concrete particles have an internal curing effect under the condition that other factors are not changed, on the basis of ensuring the construction performance of the pavement concrete, the mechanical property, wear resistance and the like of the pavement concrete meet related requirements, and compared with the performance of a control group (pavement concrete not replaced by waste aerated concrete), the performance of the pavement concrete is not greatly reduced, and engineering practice can be guided.

The invention relates to a device and a method for continuously measuring a saturated surface dry state of pre-wetted aggregate, belongs to the technical field of preparation of concrete materials, and aims to provide a simple lightweight aggregate saturated surface drying device, so that the lightweight aggregate with the wet surface can rapidly reach the saturated surface drying state. The method comprises the following steps: firstly, measuring the standard water absorption rate of the dry aggregate in a saturated surface dry state; secondly, before the dry aggregate is pre-wetted, weighing the mass of the dry aggregate in a hopper; then, calculating and obtaining the moisture content of the batch of aggregate in a surface dry and saturated state; then, after the dry aggregate is pre-wetted, weighing the mass of the pre-wetted aggregate in the hopper; then, loading the wet aggregate on a porous plate, feeding the porous plate into a drying chamber for drying treatment, and measuring the relative humidity of the drying chamber; then, calculating the moisture mass in the drying chamber; then respectively weighing the mass of water flowing out of a water collecting tank below the porous plateand the mass of condensate water in a heat exchanger; and finally, calculating the actual water carrying amount in the dried saturated surface dry aggregate when the water content is close to the water content in the aggregate surface dry and saturated water state.