ACC block stands for autoclaved cellular concrete block. The ACC block is a valuable addition to the masonry units accessible to masonry contractors. Advantages of cellular concrete block masonry over brick masonry are its lightweight design, minimal mortar use, and faster working speeds Many contractors are unfamiliar with the usage of autoclaved cellular concrete blocks. … Read more
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
Earth Excavation Checklist The following checklist should be used as a guide for better quality control over earth excavation. (1) Prior to the start of excavation operations, take photographs of the construction area, make sure that sufficient cross—sections are taken, and continue to take progress photographs during construction. (2) Review the log of borings to … Read more
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
Portland Pozzolana Cement 1. Pozzolana Pozzolana is a volcanic powder found in Italy near Vesuvius A pozzolanic material is essentially a siliceous or aluminous material which possess no cementitious properties. But it has the property when it combined with lime to produce a stable pozzolana compound it has definite cementitious properties. In the presence of … Read more
PLASTERING The following topics are covered in this post. What is plastering? What are the requirements of good plaster? Different types of mortars for plastering Number of coats of plastering How to preparation of background before plastering? What are the recommended mortars mixes for different situation? What are the defects in plastering? What is plastering? … Read more
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
DEFECTS IN BRICKWORK EFFECTS OF WORKMANSHIP ON MASONRY STRENGTH Masonry has a very long tradition of building by craftsmen, without engineering supervision of the kind applied to reinforced concrete construction. Consequently, it is frequently regarded with some suspicion as a structural material and carries very much higher safety factors than concrete. There is, of course, … Read more
Quality Control in Concrete Construction Quality of concrete construction on site can be accomplished in three distinct stages as follow Quality control before concreting Quality control during concreting Quality control after construction Stage-1 (Quality Control Before Concreting) This stage of quality control consists of two steps. Checking of specification requirements regarding excavation, forms, reinforcement and … Read more
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