Cement is the mixture of calcareous, siliceous, argillaceous and other substances.
Cement is a hydraulic binder and is defined as a finely ground inorganic material which, when mixed with water, forms a paste which sets and hardens by means of hydration reactions and processes which, after hardening retains it's strength and stability even under water.
Functions of cement:
Popular as building material.
Material with adhesive & cohesive properties.
To bind the fine & coarse aggregate together
To fill voids in between fine & coarse aggregate particle form a compact mass.
Composition of Cement
Lime Calcium Oxide (CaO) = 60 - 65% (63%)
Silica (SiO2) = 20 - 25% (22%)
Aluminum Oxide = 4 - 8% (6%)
Iron Oxide = 2 - 4 % (3%)
Magnesium Oxide = 1 - 3 %
Gypsum 1 to 4%
Types of cement - OPC, PPC, GBFSC ORDINARY PORTLAND CEMENT:
it is a hydraulic cement that hardens in water to form a water-resistant compound. The hydration products act as binder to hold the aggregates together to form concrete.
It is made by finely clinker produced by calcining to incipient fusion a mixture of argillaceous and calcareous materials: Limestone + Shale/Clay + Heat = Clinker +CKD + Exit Gas
OPC is environment friendly as well as economical
Ordinary Portland Cement is available in 3 grades - OPC-53, OPC-43, OPC-33 OPC-43 GRADE
The 43 grade OPC is the most popular general-purpose cement in the country today. The production of 43 grade OPC is nearly 50% of the total production of cement in the country.
Grade 53 means a compression strength of 53 N/ mm2 is attained on its mortar with sand after a curing period of 28 days. Same will apply to grade 43 and 33.OPC cement is used when where High Early Strength is required and for constructing high-rise buildings. It attains early strength and is fast setting, but has increased chances of micro cracking.
Advantages of OPC:
Produces highly durable and sound concrete due to very low percentage of alkalis, chlorides, magnesia and free lime in its composition.
Almost negligible chloride content results in restraining corrosion of concrete structure in hostile environments.
Significant saving in cement consumption while making concrete of grades M15, M20, M25, M35 and pre-cast segments due to high strength....
This book has been written for the Medical/Pharmacy/Nursing/ME/M.TECH/BE/B.Tech students of All University with latest syllabus for ECE, EEE, CSE, IT, Mechanical, Bio Medical, Bio Tech, BCA, MCA and All B.Sc Department Students.
The basic aim of this book is to provide a basic & best knowledge in Concrete Technology.
Concrete Technology Syllabus students of degree, diploma & AMIE courses and a useful reference for these preparing for competitive examinations.
All the concepts are explained in a simple, clear and complete manner to achieve progressive learning.
This book is divided into five chapters. Each chapter is well supported with the necessary illustration practical examples. ..
