DSCAPESARCH

Concrete Mix Design Concrete mix design is the method of optimally dosing various components of concrete,such as cement, aggregates, water,and additives, to make concrete less costly and will have specific  workability and homogeneity properties in the fresh state and strength and durability in the hardened state. Purpose of concrete mixes The main objective of the dosage of concrete mixes is to make a concrete that has the following characteristics: 1. Satisfy viability requirements in terms of drop to facilitate placement and consolidation. 2. Meets resistance requirements. 3.  Can be mixed, transported, placed and compacted efficiently. 4. Economical to manufacture. 5. Meets durability requirements to withstand the environment in which the structure is expected to serve Mixing ratio procedure Step 1. Calculate the target average compressive strength for the mixing ratio: The target 28-day average compressive strength according to clause 3.2 of IS 10262. ft = fck + 1.65...

Mosaic or Terrazzo flooring. The terrazzo flooring consists of two layers; the bottom layers of 2 cm cement concrete 1:2:4 or 1:1.5:3 as specified, and the upper layer of 6 mm thick consisting of a mix of marble chips and Cement should be of standard Specifications. The marble chips should be of 3 mm gauge, having maximum size 3 mm and minimum 1.5 mm. The sand should be coarse and well graded, clean and free from dust and dirt, etc.  The stone girit (Shingle or bajri) should be hard and tough (granite stone) 13 mm gauge. It should be clean and free from dust and dirt, etc. 32 mm (1) thick cement concrete (under layer) shall be aid in accordance with the instruction laid down in specification no.7. Dividing strips where required, including any strips in decorative design shall be bedded into the base concrete in case of ground floor. The top of the strips shall be kept at slightly higher level above the finished level of the floor, so that after grinding they are at the correct leve...

EARTH WORK IN EXCAVATION OF FOUNDATION. Earthwork in excavation  in  foundation  trenches or drains not exceeding 1.5m in width and 10sq. m in plan including dressing of sides & ramming of bottom, disposal of surplus  excavated  soil within 50m lead & 1.5m lift. All  excavation  operation shall include  excavation  and getting out the  excavated  matter. Stability of existing structures.   Before starting excavation trial pits should be dug to ascertain the depth and nature of its foundation. Shoring should be used in all cases when the depth of excavation exceeds its distance from the existing structure.  Excavation.   Foundation trenches shall be dug out to the exact width of the foundation concrete and the sides of the trenches shall be left plumb where the nature of soil admits of it. Where the soil is not good and does not permit vertical sides, the sides Fut be sloped back or shored up carefully. No exca...

QUANTITIES OF MATERIALS FOR CONCRETE Quantities of materials for the production of required quantity of concrete of given mix proportions can be calculated by absolute volume method. This method is based on the principle that the volume of fully  compacted concrete is equal to the absolute volume of all the materials of concrete, i.e. cement, sand,  coarse aggregates and water. The formula for calculation of materials for required volume of concrete is given by:- Vc = (W / 1000) + (C / 1000Sc) + (Fa / 1000Sfa) + (Ca / 1000Sca) =  Where, V = Absolute volume of fully compacted fresh concrete W =Mass of water C = Mass of cement Fa = Mass of fine aggregates Ca = Mass of coarse aggregates Sc , Sfa and Sca are the specific gravities of cement, fine aggregates and coarse aggregates respectively. The air content has been ignored in this calculation. This method of calculation for quantities of materials for concrete takes into account the mix proportions from design mix or nom...

How   To Calculate Quantity of Blocks. Volume of wall = L x B x H                           = 6 x 0.152 x 3 = 2.736 cum. Volume of One Block Without Mortar = 0.405 x 0.152 x 0.200 = 0.012312 cum. Volume of One Block With Mortar = 0.430 x 0.152 x 0.225 = 0.014706 cum. No of Blocks =   Volume of Wall / Volume of One Block With Mortar                        = 2.736 / 0.014706 = 186 Nos Blocks Volume of Total Blocks = No's of Blocks X Volume of One Block Without Mortar                                            = 186 x 0.012312...

One Way Slab Vs Two Way Slab | Difference Between One Way Slab and Two Way Slab. One Way Slab. One way slab is supported on two opposite side only thus structural action is only at one direction. Total load is carried in the direction perpendicular to the supporting beam. If a slab is  supported on all the four sides but the ratio of longer span (l) to shorten span (b) is greater than  2, then the slab will be considered as one way slab. Because due to the huge difference in  lengths, load is not transferred to the shorter beams. Main reinforcement is provided in only one  direction for one way slabs. Two Way Slab. Two way slabs are the slabs that are supported on four sides and the ratio of longer span (l) to  shorter span (b) is less than 2. In two way slabs, load will be carried in both the directions. So,  main reinforcement is provided in both direction for two way slabs. Difference Between One Way Slab and Two Way Slab. There are some b...

Types of Cement For engineering purposes, there are many types of cement but in general, ‘Ordinary Portland Cement’ (OPC) which is available in three grades should be used for house construction 33 Grade Ordinary Portland Cement: This ordinary 'Portland' cement is used maximum in the country. It is more suitable cement for masonry and general concrete works where the members are not taken to very high stresses. It is not suitable where ‘Sulphate’ is in the soil or in the ground water. 43 Grade Ordinary Portland Cement: 43 grades of cement are used where high early strength in 1 to 28 days range is required. These days the ‘Structural Engineers’ propose these cements mainly for RCC works where a member takes high tensile stress. 53 Grade Ordinary Portland Cement: 53 grades of cement are used where high early strength in 1 to 28 days range is required. These days ‘Structural Engineers’ propose these cements mainly for RCC works, where a member takes high tensi...

Distribution of  Loads  and its Effect on  Staircase Stair  slabs are usually designed to resist gravity  loads , comprising of dead  loads  and live  loads  as described below:  1) Dead  Load : The components of the dead  load  to be considered are: a) Self-weight of  stair  slab (tread/tread-riser slab/waist slab) b) Self-weight of ... LIVE LOADS:- IS 875 parts II specifies the load to be considered as UDL of intensity 5KN/m2 for public  buildings and 3kN/m2 for residential building where the specified floor do not exceed 2kN/m2 and the staircases are should not liable for overcrowding. DEAD LOADS:- Self-weight of stair slab which includes the waist slab, tread-rise,etc. Self-weight of finishes (0.5 to 1 kN/m?) Types of stairs                                                ...

Crank Length: -   Crank length is provided in Slab Shear stress is maximum at supports in Slab. So, to resist this stress we usually crank the bars at the ends of supports in slab,  Crank bar is bent up at an angle of 45 degree  with the length of 0.42 D  D = Depth of Slab-Top Cover-Bottom cover Crank is a slight bending in bars at the lap so that maintains the clear cover even at the lap position.The rule that is generally practiced is that the slope of crank 1:10 & minimum length of crank 300 mm. Formula of Crank length = (d1+d2+5)*10mm d1 =diameter of smaller bar d2 = diameter of largest bar क्रैंक लंबाई: - स्लैब शीयर में क्रैंक की लंबाई प्रदान की जाती है, स्लैब में समर्थन अधिकतम होता है। इसलिए, इस तनाव का विरोध करने के लिए, हम आमतौर पर स्लैब में समर्थन के सिरों पर सलाखों को क्रैंक करते हैं, क्रैंक बार 45 डिग्री के कोण पर मुड़ा हुआ है 0.42 डी की लंबाई के साथ D = स्लैब-टॉप कवर-बॉटम कवर की गहराई क्रैंक लैप पर सलाखों में हल्का सा झुका होता है ताकि ...

Define reinforced concrete.   Reinforced cement concrete is a composite material is made of concrete and steel reinforcement. The concrete may be assumed to work purely in compression whereas the reinforcement is predominately subjected to tension. For a large range of applications it is sufficient to consider the uni-axial response of either material. Reinforced concrete ,  concrete  in which steel is embedded in such a manner that the two materials act together in resisting forces. The  reinforcing  steel—rods, bars, or mesh—absorbs the tensile, shear, and sometimes the compressive stresses in a  concrete  structure. What is reinforced concrete used  for?  Reinforced concrete  is  used  for construction on a large scale, such as bridges, dams, piers, tall buildings and stadiums. It is most commonly  used  in domestic construction for the footings and foundations of smaller everyday dwellings. There are  four t...

Find Out Weight of Steel Bar.  W =  (D 2  / 162) X L D = Diameter of Steel Bar. (6mm,8mm,10mm,12mm,16mm etc.) L = Length of Steel Bar in Meter. W = Weight of Steel Bar in kg Suppose Dia = 16mm & Length = 1m W= (16X16 / 162) X 1 =  1.58 kg For Example:- 1. Dia = 8mm & Length 2.5m (D 2 /162) X L = (8X8 /162) X 2.5 = 0.987 kg 2. Dia = 10mm & Length 550mm [1m = 1000mm] (D 2 /162) X L = (10X10 /162) X 0.550 = 0.339 kg 3. Dia = 12mm & Length 1.1m  (D 2 /162) X L = (12X12 /162) X 1.1 = 0.977 kg 4. Dia = 25mm & Length 90cm [1m = 100cm] (D 2 /162) X L = (25X25 /162) X 0.90 = 3.47 kg    

C ement Bags Required for 200 Sq.ft Concrete Slab. Concrete Slab area = 200 Sq.ft Assume Depth of Slab = 200 mm                                                = 0.2 m                                                                             = 0.65 ft.  Volume of Slab = 200 X 0.65 = 130 cu.ft  Cement content (as per IS) Min. Cement Content = 320 kg/cu.m  Max. Cement Content = 450 kg/cu.m 1 cu.m = 35.3 cu.ft  128 cu.ft = 130/35.3 = 3.682 cu.m  : Taking 400 kg/cu.m as Cement Content Casually Taken  Total Cement Content  = 400 X 3.682 = 1472.8 kg.  1 Bag Cement Wt. is 50 kg 1472.8 / 50 = 29.456 Bags   Ap...