First, you need to obtain the app. Use a vacuum pump to gradually apply vacuum and remove the entrapped air while spinning the flask to remove the air bubbles. The bulk specific gravity test is used to determine the specific gravity of a compacted HMA sample by determining the ratio of its weight to the weight of an equal volume of water. Want to create or adapt books like this? Find the density of soil when the specific gravity of soil particle is 12 and the density of water is 9. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Your email address will not be published. What is the range of bulk density values for an organic soil? On oven drying, the density drops to 1.74 gm/cc. Soils are composed of a combination of solids (soil particles), liquids (soil water), and gases (soil atmosphere). This indicates that all the water has left the sample. NTP - Normal Temperature and Pressure - defined as 20 o C (293.15 K, 68 o F) and 1 atm ( 101.325 kN/m2, 101.325 kPa, 14.7 psia, 0 psig, 30 in Hg, 760 torr); Molecular weights can be used to calculate Specific Gravity if the densities of the gas and the air are evaluated at the same pressure and temperature. Q.3: Give the formula to determine the specific gravity (Gs). Porosity is the ratio of volume of voids to the total volume of soil. Coarse aggregate apparent specific gravity. The determination of the specific gravity method is as follows: The measuring flask with 1000ml capacity is weighed for the determination of its empty weight denoted by W 1. This can be done with a water-filled container on top of a scale or with a basket suspended in water under a scale (Figure 2). If more than 2 percent water by volume is absorbed by the sample then this method is not appropriate. Units of density are typically expressed in g cm3 or Mg m-3. Dry the sample to a saturated suface dry (SSD) condition. 3. 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. It may be necessary to wipe the larger particles separately. Some lightweight shales (not used in HMA production) can have specific gravities near 1.050, while other aggregate can have specific gravities above 3.000. Aggregate absorption is a useful quality because: It is generally desirable to avoid highly absorptive aggregate in HMA. sb= Bulk Density 4) sieve, by means of a water pycnometer. The specific gravity of soil can be calculated by using the following formula, G = Mass of soil / Mass of equal volume of water, G = Mass of soil / Mass of equal volume of water, Mass of the same volume of water, Ww = (W1 + Ws) W2. 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. Troxler Electronic Laboratories, Inc. Research Triangle Park, NC. Soil's specific surface area (s, m2/g): Depends on shape of soil particle. A change in aggregate mineral or physical properties can result in a change in specific gravity. Your email address will not be published. Certainly, the accuracy of all measurements is important. Quickly blot the sample with a damp towel and record the surface dry mass. W = Total weight of soil Android (Free)https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator Fill the flask with distilled water up to the graduation mark. Here M is total mass and V is total volume. Several important physical properties have been discussed in other labs: texture, structure, color, and consistency. 4. Specific gravities can vary widely depending upon aggregate type. Define and explain the differences among particle density, bulk density, and specific gravity. Repeat this process in ten mL intervals until you reach the 50 mL mark. Figure 8: The basket used for underwater weighing. w. The mass density of water ? Absorption should typically be below 2 percent. The equation used to calculate specific gravity is the weight of a dry sample in air divided by the weight of the sample in air minus the weight of the sample in water (i.e., the weight of water displaced by the sample). Fill around 2/3 of the flask with distilled water. Cool the aggregate to a comfortable handling temperature. S = degree of saturation of the soil These weights are used to calculate specific gravity and the percentage of water absorbed by the sample. Their common symbols are: Pavement Interactive was developed by thePavement Tools Consortium, a partnership between several state DOTs, the FHWA, and the University of Washington, as part of their effort tofurther develop and use computer-based pavement tools. $W = W_s + W_w$. Place the entire sample in a basket (Figure 8) and weigh it underwater (Figure 9). w = Density of Water = 9. The specific gravity of soil is determined using the relation: Where M 1 =mass of empty Pycnometer, M 2 = mass of the Pycnometer with dry soil M 3 = mass of the Pycnometer and soil and water, M 4 = mass of Pycnometer filled with water only. Effective unit weight is the weight of solids in a submerged soil per unit volume. Three different masses are recorded during the test. It is not a complete procedure and should not be used to perform the test. If the sample is actually still wet on the surface then the mass of the SSD sample will be higher than it ought to be, which will cause a lower calculated bulk specific gravity. Between 20o C and 25o C the density of water is essentially 1 g/cm3. Apple (Paid)https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8 As you can see from the screenshot above,Nickzom Calculator The Calculator Encyclopedia solves for the specific gravity of soil particle and presents the formula, workings and steps too. Weight-Volume Relationship from the Phase Diagram of Soil The total pore space consists of the voids between sand, silt, and clay particles and voids between soil aggregates. Take an average of 3 values these values should not vary by more than 2 to 3%. Ws = Weight of solid particles Specific Gravity of Solids The specific gravity of soil particles (G) 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. G = ? Remove the aggregate from the water and dry it until it maintains a constant mass. It is represented as 'Gm'. g/cm3 ), including solids and pore spaces. Describe several examples of soil management practices that increase or decrease soil bulk density. Upon completion of this laboratory exercise students should be able to directly measure bulk density and particle density using the graduated cylinder method for coarse textured, non-aggregated soil samples. $\gamma = \dfrac{W}{V} = \dfrac{W_s + W_w}{V}$, $\gamma = \dfrac{W_s (1 + W_w/W_s)}{V} = \dfrac{W_s}{V}(1 + w)$, Dry Unit Weight (S = w = 0) m = mass of soil The specific gravity of soil may be defined as the ratio of the mass of solids to the mass of an equivalent volume of water at 4C. The difference between Gsa, Gse and Gsb is the volume of aggregate used in the calculations. The standard bulk specific gravity test is: Specific gravity is a measure of a materials density (mass per unit volume) as compared to the density of water at 73.4F (23C). This results in less total pore volume. Therefore, after the wax sets there is no possibility of it draining out and, theoretically, a more accurate volume can be calculated. $\gamma = \dfrac{(G + Se)\gamma_w}{1 + e}$, $\gamma = \dfrac{(G + Gw)\gamma_w}{1 + e}$, $\gamma_{sat} = \dfrac{(G + e)\gamma_w}{1 + e}$, $\gamma ' = \dfrac{(G - 1)\gamma_w}{1 + e}$, $D_r = \dfrac{e_{max} - e}{e_{max} - e_{min}}$, MATHalino - Engineering Mathematics Copyright 2023. This SSD condition allows for internal air voids to be counted as part of the specimen volume and is achieved by soaking the specimen in a water bath for 4 minutes then removing it and quickly blotting it dry with a damp towel. The reference density of water at 4 o C (39 o F) is used as the reference as these are the conditions of maximum density. Lets solve an example; For example, if spherical (r = radius and = density) . Gs = Specific Gravity of Soil Particle = 12 Compact the soil by dropping onto a padded surface like a book, notebook, etc. Place the sampler over the desired sampling location, and then drive it into the soil with the slide hammer at the top of the handle. You can get this app via any of these means: Webhttps://www.nickzom.org/calculator-plus, To get access to theprofessionalversion via web, you need toregisterandsubscribeforNGN 2,000perannumto have utter access to all functionalities. High values can indicate non-durable aggregate. Unit weight, $\gamma = s \gamma_w$, Specific gravity, $s = \dfrac{\gamma}{\gamma_w}$, Physical Properties Now you're ready to calculate density. In this video we discuss in detail about the difference among apparent , bulk & effective specific gravity of aggregate. American Association of State Highway and Transportation Officials (AASHTO). Gs =Unit weight (or density) of soil sample only / Unit weight (or density) or water. W b = Weight of Pycnometer filled with water and soil. Lets solve an example; The bulk specific gravity test measures a HMA sample's weight under three different conditions (Figure 1): Dry (no water in sample). Stop when the cap of the barrel is flush with the soil surface. Slowly add Soil Sample #1 to pre-weighed graduated cylinder to the 10 mL line. Clean the specific gravity bottle well and dry it. $\gamma = \dfrac{W}{V}$, $\gamma = \dfrac{\gamma_w V_w + \gamma_s V_s}{V_v + V_s}$, $\gamma = \dfrac{\gamma_w V_w + G \gamma_w V_s}{V_v + V_s}$, $\gamma = \dfrac{V_w + G V_s}{V_v + V_s}\gamma_w$, $\gamma = \dfrac{S V_v + G V_s}{V_v + V_s}\gamma_w$, $\gamma = \dfrac{S (V_v/V_s) + G (V_s/V_s)}{(V_v/V_s) + (V_s/V_s)}\gamma_w$, Moist unit weight in terms of dry density and moisture content This is because in the normal procedure the water may not be able to penetrate the pores to the center of the aggregate particle during the soaking time. Aggregate specific gravity is needed to determine weight-to-volume relationships and to calculate various volume-related quantities such as voids in mineral aggregate (VMA), and voids filled by asphalt (VFA). Therefore, by definition, water at a temperature of 73.4F (23C) has a specific gravity of 1. Insert a 1.5 cm metal ring, a 6 cm metal core, and then a second 1.5 cm metal ring into the barrel of the core sampler, then reattach the barrel to the handle. V = Volume of the Soil Calculating the Density of Soil when the Specific Gravity of Soil Particle and the Density of Water is Given. For more accurate results it is recommended to conduct tests 3 times on the same soil sample.
