CONSTRUCTION ERRORS DURING CONCRETING AT SITE

Construction errors during concreting at site may occur due to failure to follow specified procedures and good practice or outright carelessness. Most of these errors may not lead to failure or deterioration of concrete, but they may have adverse impact on the structure with time. The construction errors which are likely to occur at site(…)

QUANTITY & RATE ANALYSIS FOR REINFORCED CONCRETE

Today we will see how to prepare rate analysis for Reinforced Concrete (RCC) work. First step to rate analysis is the estimation of labour, materials, equipments and miscellaneous items for particular quantity of reinforced concrete. The second step is to determine the component of structure for which the RCC rate analysis is required, as the(…)

FIRE PROTECTION OF HIGH RISE BUILDINGS

High-rise buildings have unique challenges related to fire protection such as longer egress times and distance, evacuation strategies, fire department accessibility, smoke movement and fire control. The numbers of persons living on high-rise buildings are high compared to low-rise buildings, and only evacuation method in case of fire is the staircase. So, the fire protections(…)

HOW TO CONSTRUCT DURABLE CONCRETE STRUCTURES

Achieving Durability of Concrete Structures: The durable concrete structures are to be conceptualised, specified, designed, contracted, constructed and maintained. To achieve the design life of the structure at reasonable maintenance cost, the following aspects are required to be taken care of: i) The structure should also be designed for environment loads and detailing done. ii)(…)

WHY WE TEST CONCRETE SRTRENGTH AFTER 28 DAYS?

Why do we test concrete compressive strength after 28 days? The table below shows the compressive strength gained by concrete after 1, 3, 7, 14 and 28 days with respect to the grade of concrete we use. Age Strength per cent 1 day 16% 3 days 40% 7 days 65% 14 days 90% 28 days(…)

REBOUND HAMMER TEST ON CONCRETE

The operation of rebound hammer is shown in the fig.1. When the plunger of rebound hammer is pressed against the surface of concrete, a spring controlled mass with a constant energy is made to hit concrete surface to rebound back. The extent of rebound, which is a measure of surface hardness, is measured on a(…)

INSPECTION & TESTING OF WELDS IN STRUCTURAL STEEL

The method of inspection of welds in structural steel should be according to IS:  822 and extent of inspection and testing shall be in accordance with the relevant applicable standard. The inspection of welds during all stages of fabrication and erection should be done for the following objectives.: i) To check the conformity with the(…)

COMPRESSIVE STRENGTH TEST ON CONCRETE CORE

Compressive Strength Test on Drilled Concrete Cores is required to determine the strength of hardened concrete in structure. Following are the specification for drilled concrete cores to be suitable for compressive strength test: Diameter of concrete core: The  diameter of the core specimen  for  the  determination  of compressive strength in load bearing structural  members shall (…)