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

HOW BEAM COLUMN JOINTS RESISTS EARTHQUAKES?

Why Beam-Column Joints are Special In RC buildings, portions of columns that are common to beams at their intersections are called beam-column joints (Figure 1). Since their constituent materials have limited strengths, the joints have limited force carrying capacity. When forces larger than these are applied during earthquakes, joints are severely damaged. Repairing damaged joints … Read more

HOW TO CHECK SUITABILITY OF WATER FOR CONCRETE MIXING?

How to check quality of drinking water

SUITABILITY OF WATER FOR CONCRETE MIXING OBJECTIVE To assess suitability of water for use in concrete mix. Equipment Measuring cylinder Cube moulds Trowel Tamping rod Vibrating table Testing machine Procedure Analyse water for its chemical compositions as per IS 3025-1964 and compare these with permissible limits given in IS: 456-2000. In case water does not … 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

HOW TO PROTECT MASONRY DURING CONSTRUCTION?

Protection of Masonry During Construction It is necessary to protect masonry during construction when the mortar is green or when masonry has not been laterally supported, against damage due to rain, frost, storm, etc. It is also necessary to protect some vulnerable parts of masonry such as jambs, corners and sills and expose masonry, during … 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

HOW TO USE NEEDLE VIBRATOR EFFICIENTLY?

Needle type concrete vibrator

Needle Vibrator These concrete vibrators are also referred to as poker or immersion vibrator. These are extensively used in building industry. A needle vibrator consists of a cylindrical casing made of steel and is vibrated by means of a flexible drive with an outer tube run from an operating machine which can be run by … Read more

HOW TO CALCULATE STRESS DISTRIBUTION OF SOIL? 2:1 METHOD

Fig-1 Approximate Stress Distribution

Stress Distribution in Soil Displacements in soil occur from stresses applied by loading forces. The distribution of stress in soil should be known for realistic estimates of displacements caused by applied loads on the supporting soil. The following methods may be used to estimate the stress distribution of soil for an applied load Q at … Read more