MASTER'S LIBRARY

Assuming 1- Grade of mortar = 1:6 (cement : sand) 2- Class A brick (19 cm x 9 cm x 9 cm) 3- Volume of brick work = 1.0 m^3, (wall size =1*1*1 =1.0 m^3) 4- Thickness of mortar = 10 mm Step 1 :- Calculation of bricks No. of bricks = (volume of brick work / volume of one brick with mortar) Volume of one brick (without mortar) = .19*.09*.09 = 0.001539 m^3 since thickness of mortar = 10 mm (0.01 m) Volume of brick with mortar = (0.19+0.01) x (0.09+0.1)x (0.09+0.1) = 0.2×0.1×0.1 = 0.002 m^3 Number of brick required in brick work volume = 1.0 m^3 therefore, No.of bricks = 1.0/ (0.002)  =  500 Nos. consider the percentage of waste  as 10 % or 15 % Total no. of bricks = 500 + (10 x 500 )/100=550 Step 2 :- Calculation for quantity of mortar Since we need 500 no of bricks volume occupied by bricks = No of bricks x volume of one brick Volume of bricks = 500 x 0.001539 = 0.7695 m^3 Volume of mortar = Volume of brick work – Volume of Bricks...

TENDERING, ESTIMATING AND QUANTITY SURVEYING – Tendering Methods & procedures: Tendering Methods & procedures: Methods of Contractor Selection: The selection of a contractor to carry out construction works in a project is a very important matter. A wrong choice may lead to an unhappy client / contractor relationship. It also may end up with dissatisfied client and sometimes even with an insolvent contractor. The client’s professional advisers should find a contracting company; That is financially stable / and has a good business record. For which the size of project is neither too small nor too large. That has a reputation for good quality workmanship and efficient organization. There are three principal methods for choosing a contractor: (a) open tendering, (b) selective tendering, (c) nomination. Open Tendering – Initiated by client’s architect/ quantity surveyor advertising in newspapers and/or inviting contractors to apply for tender documents and to tender...

CLEAR COVER TO MAIN REINFORCEMENT: 1.FOOTINGS : 50 mm 2.RAFT FOUNDATION.TOP : 50 mm 3.RAFT FOUNDATION.BOTTOM/SIDES : 75 mm 4.STRAP BEAM : 50 mm 5.GRADE SLAB: 20 mm 6.COLUMN : 40 mm 7.SHEAR WALL : 25 mm 8.BEAMS : 25 mm 9.SLABS : 15 mm 10.FLAT SLAB: 20 mm 11.STAIRCASE : 15 mm 12.RET. WALL : 20/ 25 mm on earth 13.WATER RETAINING STRUCTURES : 20/30 mm

ADMIXTURES A material other than water, aggregates, or cement that is used as an ingredient of concrete or mortar to control setting and early hardening, workability, or to provide additional cementing properties. Why is admixture used? Over decades, attempts have been made to obtain concrete with certain desired characteristics such as high compressive strength, high workability, and high performance and durability parameters to meet the requirement of complexity of modern structures. The properties commonly modified are the heat of hydration, accelerate or retard setting time, workability, water reduction, dispersion and air- entrainment, impermeability and durability factors. Types of Admixtures Chemical admixtures - Accelerators, Retarders, Water-reducing agents, Super plasticizers, Air entraining agents etc. Mineral admixtures - Fly-ash Blast-furnace slag, Silica fume and Rice husk Ash etc. Chemical admixtures 1. Water-reducing admixture / Plastici...

OPC = Ordinary Portland Cement PPC = Pozzolonic Portland cement (FYI : PPC is environment friendly as it consists fly ash in some specific percentages by parts, which is a waste product of burnt coal, usually collected from thermal power plants) OPC (m53) attains strength in a shorter time, while PPC (m43) takes longer. OPC therefore dries more quickly, but produces more heat during chemical reaction during which it gains strength, as compared to PPC. Faster is the drying process, more is the risk of cracking of cement, and therefore it need more care and more amount of water for curing in a lesser time. PPC on the other hand can attain strength equal to OPC, but takes a longer time. For a building slab, PPC is more widely used since it requires less care. The strength depends on design mix (the water cement and aggregate ratio) more than type of cement. so essentially, If you need construction to take place faster and have means for good curing, you may use OPC. But if...