For instance, if a quarry operation constantly monitors the specific gravity of its output aggregate, a change in specific gravity beyond that normally expected could indicate the quarrying has moved into a new rock formation with significantly different mineral or physical properties. The specific gravity of solid particles is defined as the ratio of the mass of a given volume of solids to the mass of an equal volume of water at 4 C. Soil Phase Relationships - CivilEngineeringBible.com Submerge sample in 77F (25C) water for 4 minutes and record the submerged mass . The equations include corrections to factor in the specific gravity values for the fraction larger than the No.4 sieve size. Determine the water content within a soil sample - TheCivilEngineer.org TheSpecific gravity of soil generally ranges from 2.60 to 2.90. Specific gravity is a unitless measurement of a sample's density relative to water. [Solved] The density of a fully saturated specimen of clay - Testbook How to Calculate and Solve for Specific Gravity of Soil Particle | Soil The voids, or pore space, are important for air and water movement and storage. Weigh and record graduated cylinder plus compact soil weight (C). Measure the length and diameter of the metal cylinders. The bulk mass density of soil is defined as the ratio of total mass to total volume. Place the entire sample in a basket (Figure 8) and weigh it underwater (Figure 9). Solution W=0.285KN, Ws=0.25KN, V=14*103*10-6=14*10-3m3 W%= e=?? Absolute or true specific gravity - civilengineering.blog s /? Soil Density - Soils Laboratory Manual Soil is a three-phase materialthat consists of solid particles and voids which are filled with water and air. Therefore, the Specific Gravity GS is calculated as: A correction is utilized to adjust the results at a reference temperature T=20C: where K is the temperature correction factor. With the dimensions of the cylinder and the weight of oven-dry soil inside the cylinder, we can calculate the bulk density. w = Density of Water. V = Volume of the Soil = 4. Specific gravity Specific gravity is defined as the ratio of the weight of a given volume of soil solids at a given temperature to the weight of an equal volume of distilled water at that temperature, both weights being taken in air. The relative density (specific gravity) of an aggregate is the ratio of its mass to the mass of an equal volume of water. B = mass of SSD sample in air (g) Effective unit weight is the weight of solids in a submerged soil per unit volume. 1993 AASHTO Flexible Pavement Structural Design, 1993 AASHTO Rigid Pavement Structural Design, Climate Change Impacts on Pavements and Resilience, E-Construction in Practice: A Peer Exchange with WSDOT and TxDOT. s= Density of Soil ASTM D 2726: Bulk Specific Gravity and Density of Non-Absorptive Compacted Bituminous Mixtures, AASHTO T 166: Bulk Specific Gravity of Compacted, AASHTO T 275: Bulk Specific Gravity of Compacted Bituminous Mixtures Using Paraffin-Coated Specimens, AASHTO TP 69: Bulk Specific Gravity and Density of Compacted Asphalt Mixtures Using Automatic Vacuum Sealing Method. If particle density remains constant, as bulk density increases porosity decreases. 4 (4.75 mm) sieve (Figure 6). Formula for void ratio | Degree of unsaturation calculator Now, Click onSoil Mechanics and FoundationunderAgricultural, Now, Click on Specific Gravity of Soil Particle underSoil Mechanics and Foundation. What Is The Specific Gravity Of Soils And Why Does It Matter? Porosity is the ratio of volume of voids to the total volume of soil. Therefore, by definition, water at 73.4F (23C) has a specific gravity of 1. properties\specific gravity - calculator.org Clean and dry the inside (above the water level) and the outer part of the flask and weigh it (, Use the funnel to carefully place the soil into the flask and weigh it (. Given: m = 36 g v = 3 mL = 1 g/mL Calculation: Density of the object = = = 12 g/mL Now, we know the density of both the elements that is the object and water. Calculating the Density of Water when the Specific Gravity of Soil Particle and the Density of Soil is Given. The forces on a particle in a liquid are buoyant force and it's weight mg. mass=Volume*density =>M=Vp*Dp (Vp=Volume of the particle, Dp=Density of the particle) =>mg=Vp*Dp*g Buoyant force=Vpi*Df*g (Vpi=Volume of the particle immersed, Df=Density of the fluid) =>Vpi*Df*g=Vp*Dp*g => (Vpi/Vp)= (Dp/Df) GS should not be confused with the soil density since it is a dimensionless unit and expresses the ratio of two particular densities. These weights are used to calculate specific gravity and the percentage of water absorbed by the sample. Preparation of Soil Sample: A representative sample of soil of 12 kg mass is taken if the maximum size of the soil particle is less than 75 mm. PDF Geotechnical and Foundation Formula Sheet All three use the aggregates oven dry weight. The following formula is used to calculate the specific gravity of a material. Bulk density is defined as the mass of the many . Briefly describe the processes of soil structure (aggregate) formation. The value of specific gravity (soil) varies between 2.65-2.80. w at 4C is 1gm/ml, 1000 kg/m 3 or 1 Mg/m 3 Basic Soil Relationships Paper towels may absorb water in the aggregate pores. It is often found that the specific gravity of the materials making up the soil particles are close to the value for quartz, that is Gs 2.65 For all the common soil forming minerals 2.5 < Gs < 2.8 We can use Gs to calculate the density or unit weight of the solid particles s = Gs w s = Gs w 3. The figure shown below is an idealized soil drawn into phases of solids, water, and air. Liquids and gases are mostly water and air, respectively. One method for determining bulk density is the core method. Bulk density is a measure of the mass of a soil per given volume (i.e. Particle density is similar to the specific gravity of a solid and is not impacted by land use. Three different masses are recorded during the test. Weight of soil mass at moist condition: 56.6 kg. emin = void ratio of the soil at its densest conditiond = current dry unit weight of soil in-situ You must have JavaScript enabled to use this form. Describe several examples of soil management practices that increase or decrease soil bulk density. From $\gamma = \dfrac{(G + Se)\gamma_w}{1 + e}$ and $\gamma = \dfrac{(G + Gw)\gamma_w}{1 + e}$, S = 0 and w = 0, Saturated Unit Weight (S = 1) SSD is defined as the specimen condition when the internal air voids are filled with water and the surface (including air voids connected to the surface) is dry. Examples of suitable units have been shown below. Home Science Classical Physics. Slowly add Soil Sample #1 to pre-weighed graduated cylinder to the 10 mL line. Typically, aggregate used in HMA production will have an absorption between just above zero and 5 percent. It is an important parameter in soil mechanics for the calculation of the weight-volume relationship. Dry the material until it maintains a constant mass. Bulk Specific Gravity Calculator. For instance, deleterious particles (Figure 2) are often lighter than aggregate particles and therefore, a large amount of deleterious material in an aggregate sample may result in an abnormally low specific gravity. Remember, the volume of the water displaced is equal to the volume of the. Soil is composed of solids, liquids, and gases. It is an important parameter in soil mechanics for the calculation of the weight-volume relationship. Bulk density is a commonly measured soil property by agriculturalists and engineers. Where SG = specific gravity, = density of the material (kg/m 3 ), W = density of water ( kg/m 3 ). The simplest method is to dry the sample in a conventional oven: [latex]\text{Mass of water}=(\text{mass of beaker}+\text{moist soil})-(\text{mass of beaker}+\text{dry soil})[/latex], [latex]\text{Mass of dry soil}=(\text{mass of beaker}+\text{dry soil})-\text{mass of beaker}[/latex], [latex]\text{Percent moisture}=\frac{\text{mass of water in soil}}{\text{mass of oven dry soil}}\times100\text{%}[/latex], [latex]\text{Dry weight}=\frac{\text{wet weight}}{1+(\frac{\text{percent moisture}}{100\text{%}})}[/latex]. You will be working with your classmates to complete it during lab. As mentioned in the background section, if a specimens air voids are high, and thus potentially interconnected (for dense-graded HMA this occurs at about 8 to 10 percent air voids), water quickly drains out of them as the specimen is removed from its water bath, which results in an erroneously low SSD weight, which leads to an erroneously low HMA sample volume measurement and thus an erroneously high bulk specific gravity. 5.9.15 BULK SPECIFIC GRAVITY AND UNIT WEIGHT OF COMPACTED HOT MIX ASPHALT (HMA) (Kansas Test Method KT-15) 1. The Soil Specific Gravity is defined as the ratio of the weight of a given volume of the material to the weight of an equal volume of distilled water. When dealing with soil samples, the average particle density of soil is 2.66 g/ (cm^3). This method has shown promise in both accuracy and precision. Your email address will not be published. PDF 1. SCOPE KT-15 AASHTO T 166 AASHTO T 2 2.1. - Kansas Department of Take an average of 3 values these values should not vary by more than 2 to 3%. Figure 7 shows the Troxler device. There is no specification for bulk specific gravity, but it is used to calculate other specified parameters such as air voids, VMA and VFA. The difference between Gsa and Gsb is the volume of aggregate used in the calculations. These two density measurements provide an important insight into the physical nature of a given soil. Porosity, n The specific weight, , of a material is defined as the product of its density, , and the standard gravity, g: =g{\displaystyle \gamma =\rho \,g} The densityof the material is defined as massper unit volume, typically measured in kg/m3. Use the thermometer to derive the temperature of the water. Figure 6: CoreLok sample vacuum sealed in a plastic bag. Rolling up the aggregate into the towel and then shaking and rolling the aggregate from side to side is usually effective in reducing the sample to a SSD condition (Video 1). Saturated surface dry (SSD, water fills the HMA air voids). Calculating the Volume of the Soil when the Bulk Density and the Mass of the Soil is Given. This indicates that all the water has left the sample. Your email address will not be published. However, aggregate and asphalt binder volumes are diffucult to measure directly, therefore a materials weight is typically measured and then converted to a volume based on its specific gravity. Saturated Unit Weight, sat Now, Click on Soil Mechanics and Foundation underAgricultural, Now, Click on Bulk Density underSoil Mechanics and Foundation. Ps = Ms/ (500-Vw) Now that you have the density of soil solids, you can calculate the specific gravity of soil solids (SG). Calculate the specific gravity of the soil solids using the following formula: Specific Gravity (G s) = W o / (W o + (W a - W b )) W o = Weight of sample of oven-dry soil, g = W ps - W p. W a = Weight of Pycnometer filled with water. S = Degree of saturation The following description is a brief summary of the test. Mathematically , G = Ms / Mw = s / w = s / w Where, s = Density of Solid w = Density of Water s = Unit Weight of Solid w = Unit Weight of Water Therefore, texture and structure govern the amount of soil pore space. 3-1. Now add exactly 50 mL of water to the graduated cylinder, record volume (E). V = Volume of the Soil. Weight of soil after dry in oven: 45.5 kg. Theoretical models to predict the capacity of helical piles are based on Soil Mechanics and an appr Seequent, The Bentley Subsurface Company's, Create a free account and view content that fits your specific interests in geotechnical engineering. What is the range of bulk density values for an organic soil? It is denoted by G. Use this information to calculate bulk density, porosity, and water-filled pore volume. Given that the specific gravity of soil particle is 12 and the density of soil is 156. A cubic metre of it might weigh 1600 kg. For more accurate results it is recommended to conduct tests 3 times on the same soil sample. Want to create or adapt books like this? The shrinkage limit of the specimen will be (adopt = 1.0 gm/cc) This question was previously asked in. As you can see from the screenshot above,Nickzom Calculator The Calculator Encyclopedia solves for the bulk density and presents the formula, workings and steps too. Ws = Weight of solid particles However, in practice the paraffin film application is quite difficult and test results are inconsistent. specific gravity, also called relative density, ratio of the density of a substance to that of a standard substance. The formulas for calculating bulk density and particle density follow: Bulk density, b = mass of oven dry soil total soil volume Bulk density, b = mass of oven dry soil total soil volume Particle density, p = mass of oven dry soil volume of soil solids Particle density, p = mass of oven dry soil volume of soil solids Figure 8.1. Coarse aggregate bulk SSD specific gravity. Porosity is the ratio of the volume of the pores in a soil sample to the total volume of the sample: [latex]\text{Porosity, }=\frac{\text{volume of pores}}{\text{total soil volume}}[/latex]. Q.3: Give the formula to determine the specific gravity (Gs). Requirements: How to Calculate and Solve for Bulk Density | Soil Mechanics and Repeat this process in ten mL intervals until you reach the 50 mL mark. The formula for calculating specific gravity of soil particle: G s = s / w Where: G s = Specific Gravity of Soil Particle w = Density of Water s = Density of Soil Let's solve an example; Find the specific gravity of soil particle when the density of water is 22 and the the density of soil is 11. Specific gravities can vary widely depending upon aggregate type. Back in the lab, weigh each canister plus moist soil. Cool the aggregate to a comfortable handling temperature. The International Information Center for Geotechnical Engineers, Step-by-Step Guide for Grain Size Analysis, VertekCPT: All you need to know about Soil Liquefaction, Using Terzaghis Equation in Foundation Design, Geotechnical Engineering Lab Manual, by Prof. William A. Kitch (Angelo State University), A list of Videos on Laboratory Testing to support Online Instruction, Splitting Tensile Strength Test (Brazilian), Volumetric flask marked with a thin ring at a specific point of its neck (graduation mark), Weigh the empty and clean volumetric flask (. Measuring Bulk Specific Gravity of Compacted Specimens Using The Troxler Model 3660 CoreReader. When a gamma ray source of primary energy in the Compton range is placed near a material, and an energy selective gamma ray detector is used for gamma ray counting, the scattered and unscattered gamma rays with energies in the Compton range can be counted exclusively. Laboratory samples are typically dry at the beginning of the test; however, field samples will typically be damp. Total weight, $W = W_w + W_s$, Void ratio, $e = \dfrac{V_v}{V_s}$, Note: $0 \lt e \lt \infty$, Porosity, $n = \dfrac{V_v}{V}$, Note: $0 \lt n \lt 1$, Relationship between e and n, $n = \dfrac{e}{1 + e}$ and $e = \dfrac{n}{1 - n}$, Water content or moisture content, $w = \dfrac{W_w}{W_s} \times 100\%$, Note: $0 \lt w \lt \infty$, Degree of saturation, $S = \dfrac{V_w}{V_v}$, Note: $0 \le S \le 1$, Relationship between G, w, S, and e, $Gw = Se$, Moist unit weight or bulk unit weight, $\gamma_m = \dfrac{W}{V} = \dfrac{(G + Se)\gamma_w}{1 + e} = \dfrac{G( 1 + w)\gamma_w}{1 + e}$, Dry unit weight, $\gamma_d = \dfrac{W_s}{V} = \dfrac{G\gamma_w}{1 + e}$, Saturated unit weight, $\gamma_{sat} = \dfrac{(G + e)\gamma_w}{1 + e}$, Submerged or buoyant unit weight, $\gamma_b = \gamma_{sat} - \gamma_w = \dfrac{(G - 1)\gamma_w}{1 + e}$, Critical hydraulic gradient, $i_{cr} = \dfrac{\gamma_b}{\gamma_w} = \dfrac{G - 1}{1 + e}$, Relative Density, $D_r = \dfrac{e_{max} - e}{e_{max} - e_{min}} = \dfrac{\dfrac{1}{(\gamma_d)_{min}} - \dfrac{1}{\gamma_d}}{\dfrac{1}{(\gamma_d)_{min}} - \dfrac{1}{(\gamma_d)_{max}}}$, Atterberg Limits Each one uses a slightly different way to determine specimen volume and may result in different bulk specific gravity values. Although it avoids problems associated with the SSD condition, it is often inaccurate because it assumes a perfectly smooth surface, thereby ignoring surface irregularities (i.e., the rough surface texture of a typical specimen). Android (Paid)https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator The formula for bulk density is (mass of dry soil) / (total volume of soil), 1 - (bulk density/particle density) for porosity, and (volume of pores) / (volume of solids) for void ratio.. g = 9.81 m/s2 Void Ratio, e Determine The Specific Gravity Of Soil - Civil Engineering Portal Android (Free)https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator An incorrect bulk specific gravity value will result in incorrectly calculated air voids, VMA, VFA and ultimately result in an incorrect mix design. Low bulk density soils are easily compacted and may settle considerably to the detriment of roads, sidewalks, and building foundations. Now, enter the values appropriately and accordingly for the parameters as required by the Mass of the soil (m)is 24 andVolume of the soil (V) is 6. Apple (Paid)https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8 The specific gravity of soil can be calculated by using the following formula,G = Mass of soil / Mass of equal volume of water Where, Mass of Soil = Ws Mass of the same volume of water, Ww = (W1 + Ws) W2 Gs (T1 C) = Ws / Ww, Copyright [2019 - 2023] [Civiconcepts.com] | by [Bhushan Mahajan], 3040 House Plans | 1200 sq ft House Plan, Specific Gravity of Soil Test Procedure, Result & Calculation, General Specific Gravity of Soil Range for Various Soils, Determination of Specific Gravity Test of Soil, Calculation Of Specific Gravity Of Soil Sample, Specific Gravity of Soil at Various Temperature, Specific Gravity of Soil Lab Report Discussion, Water Content of Soil Test Procedure, Result & Report, Ultrasonic Pulse Velocity Test on Concrete, Soundness Test of Cement Procedure and Results, Abrasion Test on Aggregate & Its Procedure, Compressive Strength of Concrete Cube Test Result 7, 14, 28 Days, What To Do If Concrete Cube Fails After 28 days, Cement of Fineness: Definition, Importance, and How to Test It, 8 Different Types Of Mop With Pros & Cons, 5 Different Types of Chains In Civil Engineering, What Is Architecture | 8 Types of Architects | Different Types of Architecture | Top Architecture Types With Pictures, 8 Different Types of Air Conditioners With Pros & Cons, 30 Types Of Shed | Different Types Of Shed In Backyard | Types Of Backyard Shed | Best Shed Styles Designs, 12 Different Types of Gardens | Most Popular Types of Gardening | Top Garden Types With Pictures, Defects In Timber | Top Defects Of Timber | 5 Different Types of Defects In Timber | Foxiness In Timber, Different Types of Chimneys For Kitchens [Pros & Cons], 15 Types of Drywall Anchors | Different Types Of Wall Anchors | Dry Wall Anchors Types | Best Types of Wall Anchors For Wall, Types Of Gutters | 22 Different Types of Gutters | Rain Gutter Downspout | Best Types of Rain Gutter For House, Explore the 15 Different Types of Door Locks for Home Security, 8 Different Types of Kitchen Cabinets for Your Dream Kitchen, 12 Types of Rugs | Different Types of Rugs With Pictures | Best Types of Rug For Living Room | Best Rug For Bedroom, Different Types of Roof Overhang and Their Advantages, 15 Different Types of Fans For Home | Ceiling Fan Type, 10 Different Types of Stoves For Your Kitchen, 22 Different Types of Drill Bits and Their Uses [PDF], Thermometer graduated in O.soC division scale. The equipment for this experiment is shown in Fig. Porosity, the percent by volume of a soil sample not occupied by solids, is directly related to bulk density and particle density. In this method the specimen is wrapped in a thin paraffin film (Figure 4) and then weighed in and out of water. The following relationships are always true: Aggregate specific gravities (Gsb, Gsa,Gse and bulk SSD specific gravity ) are all Gmm(because Gmm includes the asphalt binder, which has a lower specific gravity than the aggregate), AASHTO T 85 and ASTM C 127: Specific Gravity and Absorption of Coarse Aggregate. What is the relationship between bulk density and specific gravity $\gamma_{sat} = \dfrac{W_{sat}}{V_{sat}}$, $e = \dfrac{n}{1 - n}$ and $n = \dfrac{e}{1 + e}$, MATHalino - Engineering Mathematics Copyright 2023. Particle density is approximated as 2.65 g/cm3 , although this number may vary considerably if the soil sample has a high concentration of organic matter, which would lower particle density, or high-density minerals such as magnetite, garnet, hornblende, etc. How to calculate bulk density, porosity, and void ratio of soil? Soil physical properties control the mechanical behavior of soils and will strongly influence land use and management. Thus as soil density increases, soil porosity decreases. The sample will be held in the longer cylinder; the two 1.5 cm rings are spacers, which help ensure an undisturbed soil sample. First, you need to obtain the app. Coarse aggregate apparent specific gravity. High bulk density soils are soils with little pore space, so water infiltration is reduced, root penetration is inhibited, and aeration is restricted - reducing agricultural productivity. Relation Between Dry unit Weight, Bulk unit Weight - CivilNotePpt Thus, the bulk mass density of soil formula is p = M / V . Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. Return 50 mL sample in graduated cylinder to 50 mL beaker. at least ten times from a height of about 2-3 inches. v = volume of water / volume of bulk soil - ( m 3/m3) q v = q g r b /r l = r b q g 3. The complete procedure can be found in: Other standard tests available to determine bulk specific gravity that are not described in this section are: A compacted HMA sample (usually a SGC compacted laboratory sample or a field-obtained HMA core) is weighed dry, saturated surface dry (SSD) and submerged (Figure 1). Bulk density is the density of a "bulk" of a substance, typically expressed in kg/m3 or similar. You can also try thedemoversion viahttps://www.nickzom.org/calculator. Symbols and Notations, m = unit weight, bulk unit weight, moist unit weightd = Dry unit weightsat = Saturated unit weightb, ' = Buoyant unit weight or effective unit weights = Unit weight of solidsw = Unit weight of water (equal to 9810 N/m3) Although the Test Description section describes the standard AASHTO T 166 saturated surface dry (SSD) water displacement method, there are a number of other methods available. Soil porosity is also dependent on, and inversely related to, soil density. Absorption can indicate the amount of asphalt binder the aggregate will absorb. Place the core into a labeled, pre-weighed canister, and put on the lid. If the room temperature is different from 27 o C, the following correction should be done:-G' = kG where, G' = Corrected specific gravity at 27 o C = Weight of soil solid in a given soil mass. Remove the sampler from the soil by pushing against the handle until the vertical shaft of the handle is parallel to the soil surface. Write a mathematical expression for these relationships. To find the formula for density, divide the formula of unit weight by gravitational constant g (acceleration due to gravity). Superpave mix design is a volumetric process; key properties are expressed in terms of volume. The bulk mass density is also called the wet mass density or simply bulk density. Find the bulk density when the mass of the soil is 24 and the volume of the soil is 6. m = Mass of the Soil = 24 sb= Bulk Density Class 1 Moisture Content - Specific Gravity ( Geotechnical - SlideShare Remove the aggregate from the water and dry it until it maintains a constant mass. Let, = Weight of soil solid in a given soil mass. Lets solve an example; These two (water and air) are called voids which occupy between soil particles. Both use the aggregates oven dry weight. (Note: Specific gravity of any element is unit less parameter). Carefully cut between the two shorter rings and the main core. Soil is composed of solids, liquids, and gases. Ww = Weight of water Table.1: Observations and Calculations for Specific Gravity of Soil w s sws w w s s w s s M M . The volume includes both solids and pores. Each test takes approximately 7 minutes to conduct excluding preparation time. Soil's specific surface area (s, m2/g): Depends on shape of soil particle. Organic matter and porous particles may havespecific gravityvalues below 2.0 and Soil which has heavy substances or particles may have values above 3.0. Example 4: Determine void ratio, porosity, and degree of saturation based on known volume, weight, and specific gravity (English units) Given: (metric units) Volume of soil mass: 0.0283 m 3. The gamma ray method is based on the scattering and absorption properties of gamma rays with matter. However, of specific concern is the mass of the SSD sample. Degree of Saturation, S Troxler Electronic Laboratories, Inc. (Troxler). Figure 8: The basket used for underwater weighing. s) = Ws/Vs; 12. Unit weight, $\gamma = s \gamma_w$, Specific gravity, $s = \dfrac{\gamma}{\gamma_w}$, Physical Properties The Specific Gravity for Solids and Liquids equation (SG = / w) computes the Specific Gravity (SG) of a substance based on the ratio of mass density to density of water under standard conditions (4C). If more than 2 percent water by volume is absorbed by the sample then this method is not appropriate. So, be careful if the question is like that; derive the relation between bulk density, dry density and water content, therefore, the answer will be same.] The screenshot below displays the page or activity to enter your values, to get the answer for the bulk density according to the respective parameters which is the Mass of the soil (m)andVolume of the soil (V). It is represented as 'Gm'. PDF CHAPTER 1. SOIL PHYSICAL PROPERTIES - UC Davis The density of water varies less than 1.5 mg/cm3 over the narrow range of normal temperatures. INSTRUCTIONS: Choose units and enter the following: () The mean density of the object or liquid. The ratios given in the equations are then simply the ratio of the weight of a given volume of aggregate to the weight of an equal volume of water, which is specific gravity.
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