MID-Module-Construction-equipment

Construction Engineering

Construction Engineers lead the construction process and manage the cost, schedule, quality, and safety of a project to deliver facilities that benefit society.

Construction Equipments

Equipment used in construction projects that contribute to economy, quality, safety, speed, and timely completion of a project.

Standard types of equipment

Earth Moving equipment, Construction vehicle, Material Handling Equipment, Construction Equipment.

Classification of Construction Equipments

Earth-moving equipment, Earth-compacting equipment, Hauling equipment, Hoisting equipment, Conveying equipment, Aggregate production equipment, Equipments concrete works, Pile-driving equipment.

Role of construction engineer in construction industry

Managing contract tender processes, preparing and reviewing Bill of Quantities, establishing rapport with stakeholders, completing projects within budget and on time, resolving design issues, inspecting works, conducting safety observations, ensuring efficient use of resources, ensuring work is executed as per plans and specifications.

Advantages of equipments and machineries at construction site

Smoother and faster work, increased brand value, minimal quality defects, increased productivity and reliability, reduced manpower, environment friendly and fuel efficient, require less maintenance.

Disadvantages of equipments and machineries at construction site

Expensive to purchase and operate, require skilled technicians, need an energy source, unemployment of laborers, health hazards, potential for extreme loss, require periodic maintenance and repair.

Difference between standard and special equipment

Standard equipment is commonly used in multiple projects with standard operations, while special equipment is used for special projects with special operations.

Cost of equipment

The total cost of a construction equipment consists of ownership cost and operating cost. Inaccurate estimation of equipment cost can adversely affect the profit margin of the firm.

Initial cost, salvage value, book value, useful life

Initial cost is the total cost of acquiring the asset, salvage value is the estimated market value at the end of its useful life, book value is the value recorded on accounting books, useful life is the expected number of years the asset is useful.

Owning cost of equipment

The total cost associated with owning the equipment, including initial cost, salvage value, interest cost, taxes, insurance cost, and storage cost.

Operating cost of equipment

The cost incurred when the equipment is operated, including repair and maintenance cost, fuel cost, cost of lubricating oil and grease, tire cost, and equipment operator wages.

Depreciation cost

The decrease in value of the equipment over its useful life due to wear and tear and obsolescence.

Methods to calculate Depreciation cost

Straight-line (SL) depreciation method, Declining balance (DB) depreciation method, double-declining balance (DDB), Sum-of-years-digits (SYD) depreciation method, Sinking fund (SF) depreciation method.

Economical Life of Construction Equipment

The period of economic operation for construction equipment, where the owner aims to obtain the lowest possible cost per unit of production.

Sources of Construction Equipment

Contractors can choose to purchase or rent equipment, depending on financial advantages and conditions.

Rent with option to purchase

A rental agreement that allows the renter to purchase the equipment at a later date.

Lowest total cost

The method of equipment selection that provides the lowest overall cost for use.

Advantages of purchasing equipment

The benefits of owning equipment, including cost savings with sufficient use, availability when needed, and better maintenance and care.

Disadvantages of owning equipment

The drawbacks of owning equipment, such as higher costs, potential investment of money or credit, potential use of obsolete equipment, limited flexibility in types of work, and increased production costs.

Factors affecting equipment selection

Economic considerations, company-specific policies, site-specific conditions, equipment-specific factors, client and project-specific requirements, manufacturer preferences, and labor considerations.

Balancing of equipment

Coordinating related equipment to minimize idle time and maximize efficiency in construction operations.

Selection criteria for earthwork equipment

Factors to consider when choosing equipment for earthmoving tasks, including material quantities, available time, job conditions, soil types, and available finance.

Excavators

Heavy construction equipment with a boom, stick, bucket, and cab used for various tasks such as digging, material handling, brush cutting, forestry work, demolition, grading, lifting, mining, river dredging, and pile driving.

Backhoe

A versatile excavating equipment used for excavating below the natural surface, digging trenches, pits, grading works, and precise control of depths.

Shovel

A bucket-equipped machine used for digging, loading earth or fragmented rock, and mineral extraction, typically mounted on crawler tracks.

Dragline

A machine used to excavate soft earth from below ground and deposit or load it into wagons, suitable for bulk excavation in loose soils, marshy land, and areas with water.

Clam shell

A type of excavation equipment that has a bucket resembling a clam shell with a hinged double shell.

Application

The specific uses of a clam shell, such as handling loose materials like crushed stone, sand, gravel, and coal.

Trenching machine

A piece of construction equipment used to dig trenches, with different types including wheel trenchers, chain trenchers, micro trenchers, portable trenchers, and tractor mount trenchers.

Wheel trencher

A type of trenching machine that uses a toothed metal wheel to cut trenches in hard or soft soils.

Chain trencher

A type of trenching machine that cuts trenches with a digging chain or belt driven around a rounded metal frame, used for wider trenches in rural areas.

Micro trencher

A small rockwheel trenching machine designed for work in urban areas, capable of cutting narrower and harder trenches than chain trenchers.

Portable trencher

A lightweight trenching machine used by landscapers and lawn care specialists to install landscape edging and irrigation lines.

Scraper

A large piece of equipment used in mining, construction, and agriculture for earthmoving applications, with types including self-loading scrapers, self-propelled scrapers, towed type scrapers, tandem scrapers, twin engine scrapers, and multi-engine multi-bowl scrapers.

Dozer

A powerful machine used for pushing earth or rocks, typically equipped with a heavy steel blade or plate mounted on the front.

Blades

The different types of blades used on bulldozers, including straight blades, universal blades, S-U combination blades, and cushion dozer blades.

Rippers

The long claw-like device on the back of a bulldozer used for ripping rock or pavement to break it into smaller rubble for easier handling and removal.

Earth compacting equipment

Machines used for light or heavy compacting of soil, including rammers, vibrating plate compactors, and vibro tampers.

Smooth wheeled rollers

Heavy compacting machines used on different types of soils, available in static and vibrating variations.

Static smooth wheeled rollers

These rollers consist of one large steel drum in front and two steel drums on the rear. They have a gross weight of 8-10 tonnes.

Performance of smooth wheeled rollers

It depends on the load per cm width it transfers to the soil and the diameter of the drum. Tandem rollers weigh between 6-8 tonnes.

Vibrating smooth wheeled rollers

These rollers have drums that vibrate using rotating or reciprocating mass. They offer higher compaction levels and can be used for greater depths.

Sheepsfoot roller

This roller is used for compaction of subgrade layers. It has steel drums with projecting lugs and applies pressure up to 14kg/sq cm or more.

Pneumatic Tyred Rollers

These rollers, also known as rubber tyred rollers, are used for compaction of coarse grained soils with some fines.

Grid Rollers

These rollers are used for compaction of weathered rocks and well-graded coarse soils, but are not suitable for clayey soils, silty clays, and unconsolidated soils.

Hauling equipment

Equipment used for transportation of materials.

On-Highway

Road vehicles designed to be used on public roads for hauling materials.

Off-Highway

Road vehicles designed to be used on construction sites and can also be used on public roads, which may or may not comply with highway regulations.

Trucks

Highly mobile vehicles used for transporting construction materials, with capacities ranging from 0.4CUM to 20 CUM and speeds ranging from 10 KMPH to 40 KMPH.

Dump trucks

Heavy-duty trucks with a strongly built body that hinges on the truck chassis. They can dump the load either at the rear end or on one side.

Bottom dump trucks

Similar to semi-trailers, these trucks discharge material from the bottom by opening two longitudinal gates.

Dumpers

Open 4-wheeled vehicles with a load skip in front of the driver. They can be used to dump the load and are diesel powered.

Tippers

Lorries that can discharge material by gravity by raising the front portion. They are best suited for rough works, mining, quarrying, and carrying bulk loads.

Trailers

Unpowered vehicles pulled by powered vehicles, used to transport equipment and defense armaments.

Tractors

Multi-purpose machines used mainly for pulling and pushing other equipment. They can be classified as crawler type tractors and wheel type tractors.

Drilling and Blasting

The controlled use of explosives and other methods to break rock for excavation, commonly practiced in mining, quarrying, and civil engineering.

Drilling

The process of making a hole in hard materials such as rocks and earth.

Drill bits

Cutting tools used to create cylindrical holes during drilling operations.

Forged bits

Drill bits made from a single length of drill steel in various shapes, such as circular, hexagonal, and octagonal.

Detachable bits

Steel bits that can be attached or removed from a drill, easily replaced and resharpened.

Percussion drills

Types of drills that include jackhammers or sinkers, stop hammers, and drifters.

Abrasion drills

Types of drills used for abrasive rock.

Blasthole drills

Types of drills used for blasting holes.

Diamond drills

Types of drills used for drilling in hard materials, such as diamonds.

Shot drills

Types of drills used for shot blasting.

Fusion piercing

A drilling technique used to create holes by melting the material.

Drifter

A heavy duty rock drill used for drifting and tunnelling, mounted on tractors, crawlers, wagons, etc. It is hydraulically or pneumatically operated and can drill holes up to 152mm diameter and 40 meters depth in hard materials, rocks, or concrete structures.

Abrasion Drills

Grind rock into small particles through the abrasive effect of a rotating bit. There are three types:blast-hole drills, shot drills, and diamond drills.

Blast-hole Drills

Rotary drills consisting of a steel pipe drill stem with a roller bit that disintegrates the rock as it rotates over it. Suitable for soft to medium rocks.

Shot Drills

Rotary drills whose bit consists of a roughened surface steel pipe. Can drill holes up to 180m and can be used for rocks of any hardness.

Diamond Drills

Rotary drills whose bit consists of a metal matrix with diamonds that disintegrate the rock while rotating. Suitable for very hard rock, especially in tunnelling. Expensive and special equipment.

Square Pattern

A drilling pattern where drill holes are drilled in rows, one behind the other.

Staggered (or Triangular) Pattern

A drilling pattern where the second row of drill holes is positioned midway between the first row of holes.

Single Row Blasting Pattern

A drilling pattern where the holes are drilled in a single row. Specific explosive consumption is low, but there is a higher risk of fly rock.

Multi Blasting Pattern

A drilling pattern where the holes are drilled in several rows, which can be staggered or square. Blasting can be carried out using wedge cut pattern or diagonal blasting pattern.

Wedge Cut Pattern

A drilling pattern adopted in hard and medium-hard rocks, where the distances from the middle to the ends are fixed.

Diagonal Blasting Pattern

A drilling pattern that reduces secondary blasting. Blast holes can be drilled in a square or staggered pattern, and proper distances must be maintained to avoid cut off.

Blasting

The process of breaking rocks into smaller pieces using explosives.

Detonators

Devices that initiate the explosion of another explosive in a continuous chain. They are used with dynamite and can be fired by fuse or electric sparks.

Explosives

Blasting powder and dynamite are commonly used explosives. Blasting powder is a mixture of charcoal, sulphur, and potassium nitrate or sodium nitrate. Dynamite consists of 25% sandy earth saturated with 75% nitro-glycerine. Dynamite is sold in cartridges and is used for tunnelling and quarrying work.

Fuses

Small ropes of cotton with a core of gunpowder used to ignite explosives. They burn at a rate of about 1 cm/sec and allow the person firing the charge to move to a safe distance before the explosion.

Firing Charge

The common practice of firing multiple holes at once using parallel circuits, series circuits, or a combination of both. Continuity is tested with a galvanometer to avoid misfires.

Blasting Cap

A small sensitive secondary explosive device used to detonate explosives. Safer to use in commercial mining, excavation, and demolition.

Transporting, Storing & Handling of Explosives

Guidelines for safely transporting and storing dynamite and detonators, including keeping them separate, using warning signs on vehicles, and following safety measures to prevent accidents.

Step by Step Procedures of Blasting in Hard Rock

The process of drilling blast holes, charging them with explosive materials, using electric detonators to initiate the primer, and firing the fuse to carry out the blast. Blasting mats may be used to suppress dust and noise and prevent fly rock.

Pile Driving Equipment

Equipment used to lift and drive piles into position, including pile driving rigs, pile driving hammers, and vehicles like wagons, trucks, or trailers.

Pile Hammer

A special pile driving device used to install piles. It can be suspended from a crawler crane, supported on a pile driver frame, or carried on a barge for water construction. The hammer is guided between two parallel steel members called leads.

Pile Driving Hammers

Different types of hammers used in pile driving, including drop hammer, single-acting hammer, double-acting hammer, diesel hammer, and vibratory hammer.

Drop Hammer

A type of pile driving hammer where a heavy ram is lifted and released to drop on the pile. Slow but used when only a small number of piles are driven.

Single-Acting Hammer

A type of pile driving hammer where a heavy ram is lifted by steam or compressed air and dropped by its own weight. Energy is equal to the weight of the ram times the height of fall.

Double-Acting Hammer

A type of pile driving hammer that uses steam or air to raise the striking parts and impart energy during the downstroke. Provides higher frequencies and strikes at a relatively high velocity.

Diesel Hammer

A small, lightweight, and highly mobile pile driving hammer. The ram is raised and fuel is injected, creating an explosion that advances the pile. Used in soft soils, but may require manual lifting if the pile advance is too great.

Vibratory Hammer

A pile driving hammer that uses counter-rotating eccentric weights to vibrate at a high frequency and provide vertical impulses. Reduces driving vibrations, noise, and has a high speed of penetration.

Advantages and Disadvantages of Each Pile Driving Hammer Type

Summarizes the advantages and disadvantages of single-acting hammer, double-acting hammer, diesel hammer, and vibratory hammer in terms of driving heavy piles, driving speed, headroom requirement, and suitability for different soil conditions.

Centrifugal Pump

A type of pump used to transport fluids by converting rotational kinetic energy into hydrodynamic energy. It consists of several parts, including impeller, casing, volute, and shaft.

Impeller

A wheel or rotor with backward curved blades or vanes that is mounted on a shaft and rotates to create fluid flow.

Casing

An air tight chamber that surrounds the impeller in a centrifugal pump.

Suction Pipe

A pipe connected to the inlet of a pump or the center of the impeller, used to draw liquid from a suction tank.

Delivery Pipe

A pipe connected to the outlet of a pump that delivers liquid to the desired location.