specific surface of cement unit
Like sand, gravel, anvils, and the dragon egg, concrete powder obeys the law of gravity. For Portland Puzzolana Cement : The residue present in PPC cement should not exceed 5% by the dry weight of cement. The fineness of cement is a measure of the size of particles of cement and is expressed in terms of specific surface area of cement. Concrete Masonry Unit (CMU) Surface Finishes As with shapes, there are a large number of finish options so you can make the utilitarian gray concrete block look much more aesthetically pleasing. Unit Weight . Be sure to meet with your local CMU representative to learn about what types of finishes they offer and at what cost premium. A cement is a binder, a substance used for construction that sets, hardens, and adheres to other materials to bind them together. (φ = 52%) Slurry volume is calculated by considering volume additives. We know that specific gravity of cement or Density of cement is ranging between 3.1-3.16g/cc by this, cement is 3.16 times heavier than water of the same volume. Specific surface is expressed as the total surface area in square meter of all the cement particles in one Kg of cement. the unit weight of a dry material (gdry) divided by the unit weight of water (gwater). The aim is to determine the fineness or surface area per gram of the cement. gcement = 3.15 x 62.4 lb/cu ft = 196.56 lb/cu ft Bulk specific gravity of concrete materials This is a Volumetric Calculation. Thus, the unit of fineness of cement is m²/Kg. After drying the solution with beacons, the surface is moistened with water. Excessive presence of moisture content in cement effects Workability and strength of cement. Conventional cement-sand mortar is mixed on the basis of a ratio of 1 part cement to 3 parts sand with the addition of water at the rate of 0.5 liters per 1 kg of cement. Unit weight (UW) or bulk density is the weight of a given volume of material. The solution is mixed using a mixer or nozzle on the drill. The higher the specific surface is, the finer cement will be. Bulk Density of Aggregate: The approximate value of bulk density for aggregate usually used for normal-weight concrete varies between 1200-1750 Kg/m 3 or 75 to 110 lb/ft 3. PRINCIPLE: The fineness of cement is measured as specific surface. APPARATUS: The specific surface of this type of cement should not be less than 300 m2/kg. Specific surface is expressed as the total surface area in square meters of all the cement particles in one kilogram of cement. Assuming we need 2 m 3 of concrete for M20 Concrete Mix, (Mix Ratio, M20 = 1 : 1.5 : 3) Total Part of the Concrete = 1+1.5+3 = 5.5 Parts. Unit Conversion Reminder: 1 cu.ft bulk cement = 1 sack = 94 lb Specific Gravity of Portland Cement = 3.14 (like number π in math) 1 sack of Portland Cement = 94/(3.14*62.4) = 0.48 net cu.ft. For Cement, Sand and Coarse Aggregate. Concrete powder is a solid block that comes in the 16 regular dye colors. Gs = gdry / gwater or gdry = Gs x gwater To determine the unit weight of a substance like cement, multiply the specific gravity of the cement by the unit weight of water. The specific surface of this type of cement should not be less than 325 m2/kg. The value of constant ‘K’ can be determined by using a standard cement of known specific surface area and measuring the value of ‘T’ for a standard weight of cement which is normally taken as 2.8 gms. While in air permeability method or sedimentation method, the fineness of cement is expressed in terms of the specific surface area of cement. However, since the porosity of most rocks used in concrete is 1 to 2%, the values of all specific gravities are approximately the same; in the range of 2.5 to 2.8. Therefore, Cement Quantity = (Cement Part / Concrete Parts ) * Concrete Volume For the present case the specific surface area of standard cement is given as 3400 cm2/gm & the time ‘T’ is measured as 49 seconds Concrete Ingredients Calculation.