Advantages of PPC in Fresh Concrete Portland pozzolana cement (PPC) has following advantages when concrete is in its fresh state. 1. Workability Portland pozzolana cement has spherical cement particles and they have higher fineness value. Due to the spherical shape concrete move more freely and more fineness of particles allows better filling of the pores. … Read more
Aim To determine volume of concrete per batch, where nominal maximum size of aggregate does not exceed 38 mm. Apparatus Balance – Sensitive to 0.01 kg Tamping bar – Length 38 cm, Weight 1.8 kg Cylindrical mould – Dia = 250 mm, Height = 280 mm, Capacity = 0.01m3 Step by Step Procedure to Calculate … Read more
Concrete flooring is a common type of flooring adopted by many building owners. Concrete flooring can be used in residential, commercial, institutional & public buildings of all types. Before choosing concrete flooring as an option for your building construction, you should know the advantages and disadvantages of it. Advantages of Concrete Flooring 1. Durability A … Read more
While inspecting aggregate for quality control purpose, it is required to describe its physical properties, because physical properties of aggregate have an effect on the property of concrete. The physical properties of aggregate which should be described are given below. Name of parent rock & Group name Particle Shape Surface Texture Let us see how … Read more
Sometime it may happen that, the aggregate available at site is not conforming to the desired grading. In such case two or more aggregates from different sources may be combined to get the required grading. Fineness modulus value can be used as a technical way to blend coarse aggregate with fine aggregate to produce desired … Read more
Sampling of Fresh Concrete To ensure it is representative of the whole truck load, a standard sample consists of scoopfuls taken from different parts of the batch and collected in bucket. Scoopfuls must be taken through the moving stream, as the load is discharged, sampling the whole width and depth (not just the top part). … Read more
Effects of Hot Weather on Concrete Any operation of concreting done at atmospheric temperature above 400C may be put under hot weather concreting. The effect of hot weather may be as follows: Accelerated setting: A higher temperature of fresh concrete results in a more rapid hydration and leads to reduced workability/ accelerated setting. This reduces … Read more
Objective Determination of unit weight or bulk density and void of aggregates. Equipments Name Capacity 1. Balance Sensitive to 0.5% of weight of material 2. Cylindrical metal measure Of 3 litre capacity (for fine aggregate) Of 15 litre capacity (for aggregate upto 40mm) 3. Tamping rod 16 mm dia. and 60 cm long Sample Preparation … Read more
The amount of aggregate sample to be collected is dependent on the maximum nominal size of aggregate. The quantity of aggregate sample should be of such amount, so that the required test can be performed to judge its quality. Sample of aggregate is collected using a sampling scoop. Collect a no of increments (at least … Read more
Sampling is of equal importance to testing and a man collecting samples should use every precaution to obtain samples that will show the true nature and condition of the materials which they represent. Aggregate Sampling from Stockpile Using a front end-loader, dig into the stockpile and set aside small pile of 10 to 15 ton … Read more