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Showing posts from October, 2019

Batching and mixing involved in concreting

The following are the process of manufacturing good concrete. They are Batching Mixing Transporting Placing Compacting Curing Finishing Batching  Batching involves volume batching in terms 35 litres and weight batching in terms of 50 kg. Automatic batching plants - suitable for ready mix plants. Mixing Mixing involves both hand mixing and machine mixing. Mixers involved are tilting, non tilting and reversing. Transporting concrete Mortar plan Wheel barrow, hand cart Crane, bucket and rope way Truck mixer and dumpers Belt conveyors Chute Skip and hoist Pump and pipe line Helicopter      Concrete production is the process of mixing together the various ingredients water, aggregate, cement and additives to produce concrete. Nowadays concrete production takes place in a large type of industrial facility called concrete plant. In US 70% of the concrete is produced in concrete plants where as in India only 25% is produced in concrete plants. Conc

Shotcrete

Shotcrete Shotcrete is mortar or concrete conveyed through a hose and pneumatically projected at high velocity onto a surface, as a construction technique. Shotcrete undergoes placement and compaction at the same time due to the force with which it is projected from the nozzle. It can be impacted onto any type or shape of surface, including vertical or overhead areas with or without reinforcement. Shotcrete is usually an all inclusive term that can be used for both wet mix and dry mix versions. In the pool construction trade however, the term shotcrete refers to wet mix and 'gunite' refers to dry mix, these two terms are not interchangeable. Types of shotcrete Fibre reinforced shotcrete Unreinforced shotcrete is a brittle material that cracks and displaces when subjected to tensile stresses and strains. Addition of fibres to the shotcrete mixture adds ductility to the material, energy absorption capacity and impact resistance. Composite material is capable of sustainin

Demolition of buildings

Demolition means dismantling, razing, destroying or wrecking any building structure or any part thereof by preplanned and controlled methods.  The three things involved in demolition of a building are   1. Demolition planning   2. Precautionary measures  3. Methods of demolition Demolition planning  Demolition planning includes building appraisal such as survey, structural survey, demolition plan and stability report including calculations. Termination of utilities. Planning for handling hazardous materials.  Prior to carrying out any building demolition, detailed building appraisal by means of surveys and appropriate assessments shall be required. In general, the surveys shall include a building survey and a structural survey with photographs or videos taken for future reference. Based on the findings of these surveys, a demolition plan shall then be prepared.  Building survey  The building survey shall cover the following   1. The constructi

Rigging and accessories for rigging

Rigging  Rigging is the process of material handling, installing or moving or relocation of structural components by lifting or rolling using hoisting tools like block and tackle, wire ropes, tumbuckles, clevis, jacks used with crane s and other lifting equipment.  Rigging plan  Rigging plan is developed every time a heavy load is being lifted.  Basic idea behind a rigging plan is to have control and establish safety precautions. Important planning process that will identify all hazardous situations that might be encountered during lifting. Types of rigging plan  Three major classification of lifting plans are critical lifts, ordinary lifts and pre engineering lifts.  Depending on the type of lift, then the rigging plan will have different concept under evaluation to determine the steps needed to complete a safe rigging and lifting process. Ordinary lifts  Ordinary lifts are the easiest ones to handle. They will normally require a verbal planning process and prelimin