Our aim is to mix the fine aggregate & coarse aggregate in such a ratio so that the final combined aggregate gives the specified or desirable surface index. Follow the below mentioned steps to find the proportion of fine to coarse aggregate. Procedure Calculate the total surface index of fine aggregate (let it be x) … Read more
Objective To determine quantity of silt in fine aggregates in the field Theory There are two types of harmful substances preset in fine aggregates i.e. organic matter produced by decay of vegetable matter and/or clay and silt, which form coating thus preventing a good bond between cement and the aggregates. If present in large quantities, … Read more
Output of a Concrete Mixer The output of a mixer essentially depends upon the capacity of a mixer. In addition, it depends upon the duration of mixing, supply of materials to the mixer and the speed at which charging and discharging operations are carried out. Sometimes the speed of transporting concrete from mixer to the … Read more
Objective Determination of CBR of soil either in undisturbed or Remoulded condition Reference Standards IS: 2720(Part 16)-1973- Methods of test for soils: Laboratory determination of CBR. Equipments / Apparatus Compression machine Proving ring, Dial gauge, Timer Sampling tube Split mould Vernier caliper, Balance Preparation sample The test may be performed (a) On undisturbed soil specimen … Read more
Bricks are extensively used as building material in most of the construction work. The quality of a structure or building is therefore dependent upon the quality of bricks used there in. We cannot test each and every brick to inspect its quality as it is impractical. That is why a sampling method or procedure must … Read more
Bricks which are used in construction works are burnt bricks. They are classified into 4 categories on the basis of its manufacturing and preparation, as given below. First class bricks Second class bricks Third class bricks Fourth class bricks 1. First Class Bricks These bricks are table moulded and of standard shape and they are … Read more
Aim To determine the relative density or density index of cohesionless soil Theory Relative density is also known as density index. It is defined as the ratio of difference between the void ratio of a cohesionless soil (i.e. sand) in the loosest state and any given void ratio to the difference between its void ratios … Read more
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
Objective To determine the workability of freshly mixed concrete by using of Vee – Bee consistometer apparatus. Scope and Significance The workability of fresh concrete is a composite property, which includes the diverse requirements of stability, mobility, compactability, placeability and finishability. There are different methods for measuring the workability. Each of them measures only a … Read more
The following points should be remembered before proportioning a concrete mix a per IS-10262-2009. This method of concrete mix proportioning is applicable only for ordinary and standard concrete grades. The air content in concrete is considered as nil. The proportioning is carried out to achieve specified characteristic compressive strength at specified age, workability of fresh … Read more