PACKING DENSITY OF AGGREGATE
The packing density of aggregate gives an indication of how efficiently aggregate fill a certain volume and for that reason is such an important concept in concrete technology.
Concrete Technology
10+ TECHNICAL REQUIREMENTS ON DURABILITY OF CONCRETE [IS-456]
From High Strength to High Performance Concrete Durability of concrete is now becoming the major concern for engineers as concrete may deteriorate with time in several ways. The most common durability failures in an outdoor climate are due to reinforcement corrosion or frost attack. In special environments concrete may suffer from chemical attack by various … Read more
5 FUNCTIONAL REQUIREMENTS OF FORMWORK FOR CONCRETE STRUCTURE
Essential requirements of formwork are it should be strong enough to take the dead loads, live loads, incidental loads and other loads expected during construction before attaining the strength by the concrete.
4 FUNDAMENTAL FACTORS TO CONSIDER DURING CONCRETE MIX PROPORTIONING
The process of selecting concrete mixture proportions is a process of optimization of several desirable characteristics based on the project requirements. The characteristics to be optimized are economy, strength, durability, and placeability. 1. Economy. The primary reason for systematically determining mixture proportions is economy. The maximum economy can be achieved by minimizing the amount of … Read more
7 FACTORS INFLUENCING REBOUND HAMMER TEST OF CONCRETE
Rebound Hammer Test The Schmidt rebound hammer is principally a surface hardness tester with little apparent theoretical relationship between the strength of concrete and the rebound number of the hammer. However, within limits, empirical correlations have been established between strength properties and the rebound number. Further, scientist has attempted to establish a correlation between the … Read more
6 FOCAL PROPERTIES OF CONCRETE IN FRESH AND HARDENED STATE
Properties of Hardened Concrete 1. Strength: Concrete is strong in compression but relatively weak in tension and bending. It takes a great deal of force to crush concrete, but very little force to pull it apart or cause bending cracks. Compressive strength is determined primarily by the amount of cement used, but is also … Read more
HOW AGGREGATE PROPERTIES AFFECTS CONCRETE PROPERTIES?
INFLUENCE OF AGGREGATE PROPERTIES ON CONCRETE Aggregates influence the properties of concrete/mortar such as water requirement, cohesiveness and workability of the concrete in plastic stage, while they influence strength, density, durability, permeability, surface finish and colour in hardened stage. Aggregates are generally classified into two categories viz. natural and manufactured/processed. Geologically aggregates may be obtained … Read more
AN INTRODUCTION TO CEMENT CONCRETE FOR BEGINNERS
CEMENT AND CONCRETE – ARE THEY THE SAME? Many people think that cement and concrete are the same product – they are not. Cement is a dry powdered chemical that, when mixed with water, slowly reacts to form a new hard, solid compound. On the other hand, concrete is a mixture of cement blended with … Read more
3 MAJOR COMPONENTS OF QUALITY CONTROL OF READY MIX CONCRETE
QUALITY CONTROL OF READY MIX CONCRETE Quality control of ready-mixed concrete may be divided into three components, 1. Forward control, 2. Immediate control and 3. Retrospective control. FORWARD CONTROL: Forward control and consequent corrective action are essential aspects of quality control. Forward control includes the following. • Control of purchased material Quality • Control of … Read more
6 PROPERTIES OF CONCRETE USED BY DESIGNERS
PROPERTIES OF HARDENED CONCRETE The following are the properties of concrete in its hardened state, used by the designer during design process of reinforced concrete structure. 1. Compressive Strength The characteristics strength is defined as the strength of concrete below which not more than 5% of the test results are expected to fall. As per … Read more