10+ TECHNICAL REQUIREMENTS ON DURABILITY OF CONCRETE [IS-456]

Durability of concrete

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

4 FUNDAMENTAL FACTORS TO CONSIDER DURING CONCRETE MIX PROPORTIONING

Self compacting concrete

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

FIRE RESISTING PROPERTIES OF COMMON BUILDING MATERIALS

Fire resisting properties of common construction material-min

FIRE RESISTING PROPERTIES OF COMMON BUILDING MTERIALS Fire resisting properties of common building materials such as stone, brick, timber, cast-iron, glass, steel and concrete are mentioned below. 1. STONE The stone is a bad conductor of heat. But it suffers appreciably under the effects of fire. The stone is also liable to disintegrate into small … Read more

4 PRIMARY CEMENT COMPOUNDS & THEIR ROLES

cement compounds

Compounds of Cement About 90-95% of a Portland cement is comprised of the four main cement minerals, which are C3S, C2S, C3A, and C4AF, with the remainder consisting of calcium sulphate, alkali sulphates, unreacted (free) CaO, MgO, and other minor constituents left over from the clinkering and grinding steps. The four cement minerals play very different … Read more

SPLITTING TENSILE STRENGTH TEST OF CONCRETE (IS-516)

Determine Splitting Tensile Strength of Cylindrical Concrete Specimens Objective: This method covers the determination of the splitting tensile strength of cylindrical concrete specimens Reference: IS: 516 – 1959, IS: 1199-1959, SP: 23-1982, IS: 10086-1982 Theory: Age at Test – Tests shall be made at recognized ages of the test specimens, the most usual being 7 … Read more

WHETHER OR NOT TO SELECT CONCRETE FOR CONSTRUCTION?

concrete mix proportions

FACTORS AFFECTING CHOICE OF CONCRETE FOR A STRUCTURE The choice of whether a structure should be built of concrete, steel, masonry, or timber depends on the availability of materials and on a number of value decisions. 1. Economy Frequently, the foremost consideration is the overall cost of the structure. This is, of course, a function … Read more

WHAT ARE THE PROPERTIES OF AIR ENTRAINED CONCRETE?

Air entrained concrete

AIR ENTRAINED CONCRETE A major advance in concrete technology in recent years is the introduction of tiny disconnected air bubbles into concrete called air entrainment. Air entrained concrete results from using either an air-entraining cement or an air-entraining admixture during mixing. Adding entrained air to concrete provides important benefits in both plastic and hardened concrete, … Read more

HOW TO DO FLEXURAL STRENGTH TEST OF CONCRETE?

Flexural Strength Test Arrangement

FLEXURAL STRENGTH TEST OF CONCRETE Objective To determine the Flexural Strength of Concrete, which comes into play when a road slab with inadequate sub-grade support is subjected to wheel loads and / or there are volume changes due to temperature / shrinking. Reference Standards IS: 516-1959 – Methods of tests for strength of concrete Equipment & … Read more

HOW TO MAKE TEST CUBES FROM FRESH CONCRETE?

Self compacting concrete

Making of Test Cubes From Fresh Concrete IS-456 has laid down the acceptance criteria of quality concrete. In all the cases, the 28-days compressive strength shall alone be the criterion for acceptance or rejection of the concrete. 7 days compressive strength of concrete can be carried out in order to get a relatively quicker idea … Read more

VOLUME BATCHING OF CONCRETE – THEORY & EXAMPLE CALCULATION

Concrete MIx

What Is Volume Batching of Concrete? Batching of concrete means measuring different ingredients of concrete (i.e. cement, sand, coarse aggregate and water) before mixing it. When this measurement is done on the basis of volume, we call it Volume Batching. Below are mentioned some of important points to remember before adopting volume batching method in … Read more