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A civil engineer turned writer, the girl of 22 set off the journey to freelance content creating since 2019. The impact she could make in people's lives acted as the fuel and the journey still continues in high spirits. This young thrashing blood offers 100% conversion guaranteed contents to your business. Throw brickbats or bouquets and of course, your writing requirements to anaswara.r.s.cet@gmail.com
Roads, TRANSPORTATION ENGINEERING

Bitumen for roads – Bitumen Uses, Grades and Types

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Bitumen for roads is an important topic to understand when it comes to road construction. Bitumen is used in road construction because of the wide range of features and advantages it possesses over other pavement construction materials. The significance of bitumen in the construction of roads will be demonstrated in this article. In addition, we shall see bitumen road layers, various bituminous materials, cutback bitumen, bitumen grade, and bitumen properties.

  1. Bitumen for roads – Bituminous binder types
    1. Bitumen vs Tar – Comparison
    2. Tar manufacturing
  2. Desirable properties of bitumen- an important topic in bitumen for roads
  3. Bitumen for roads – Types of Bituminous materials
    1. Cutback bitumen
    2. Bituminous emulsion
  4. Grade of bitumen for roads – Types and Uses
  5. Bitumen road layers

Bitumen for roads – Bituminous binder types

There are two types of bituminous binder for road construction.

  • Bitumen (by distillation of crude oil)
  • Tar (Produced from coal)

So, what are the difference between them?

Bitumen vs Tar – Comparison

The table below shows a comparison between tar and bitumen.

BitumenTar
Petrolium productDistillation of coal or wood
Soluble in carbon disulphide and carbon tetrachlorideSoluble in toluene only
Temperature succeptibility is lowTemperature succeptibility is higher than bitumen
Free carbon content is lessFree carbon content is more
Comparison between tar and bitumen

Now, let’s sneak into the manufacturing of tar, being one of the important bituminous materials

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Tar manufacturing

Bitumen for roads - Construction in progress
Bitumen for roads – Construction in progress

Generally, tar is made by heating coal inside a chemical apparatus. Most tar is produced from coal as a byproduct of coke production, but it can also be produced from petroleum, peat or wood.

The major steps in tar manufacturing are,

  • Coal undergoes carbonation and produces crude tar
  • Crude tar undergoes distillation/ refining and produces a residue
  • The residue blends with distilled oil fraction and produces tar

I am going to tell more about the properties of bitumen now.

Also read: Classification of roads-5 types of roads full details

Desirable properties of bitumen- an important topic in bitumen for roads

Bitumen for roads - Properties
Bitumen for roads – Properties

The desirable properties of bitumen are,

  1. Viscosity of bitumen during mixing and compaction is adequate
  2. Bituminous material should not highly temperature and susceptible
  3. In presence of water the bitumen should not strip off from aggregate
  4. The adhesive property of bitumen binds together all the components without bringing about any positive or negative changes in their properties
  5. Bitumen is insoluble in water and can serve as an effective sealant
  6. Due to versatility property of Bitumen it is relatively easy to use it in many applications because of its thermoplastic property
  7. Bitumen play a vital role in distributing the traffic loads on the pavement to the layers beneath

Bitumen for roads – Types of Bituminous materials

Okay. So, what are the types of bituminous materials that are used in flexible pavement construction? Below is the list for you.

  1. Paving grade material
  2. Modified bituminous binder
  3. Cutback bitumen
  4. Bitumen emulsion

Among the list, cutback bitumen is the major. Let me tell you more details about cutback bitumen.

Cutback bitumen

Cutback bitumen is the bitumen the viscosity of which is reduced by a volatile diluent. It is used in low-temperature mixing.

Three types of cutback bitumen are available

  1. Rapid curing
  2. Medium curing
  3. Slow curing

The diluent while mixing varies with the type of cutback bitumen.

Type of cutback bitumenDiluent
Rapid curingNafthal, gasoline
Medium curingCarosine or diesel oil
Slow curingHigh boiling point gas oil
Type of cutback bitumen and suitable diluent

Bituminous emulsion

bitumen emulsion
Bitumen emulsion

A bitumen emulsion is a liquid product in which a substantial amount of bitumen suspended in a  finely divided condition in an aqueous medium and stabilized by means of one or more suitable material

Three types of bitumen emulsions are available

  1. Rapid setting
  2. Medium setting
  3. Slow setting

Also read: Alignment of road: Factors affecting- obligatory points with figures

Grade of bitumen for roads – Types and Uses

To determine the grade of bitumen, penetration test is conducted. The results are expressed in 1/10 mm. When penetration value is represented as 80/1000, it is called grading of bitumen.

The old method of grading is viscosity test. Two viscosities kinematic and absolute and penetration value by penetration test results are collected. Based on this, bitumen is graded. The tables shows the grade of bitumen and values of viscosity in accordance with penetration.

Grade of bitumenAbsolute viscosityKinematic viscosityPenetration
VG 1080025080- 100
VG 20100030060- 80
VG 30240035050- 70
VG 40320040040- 60
Grade of bitumen and viscosity

Let me tell you the application of each of the grade of bitumen now.

VG- 10- Used in spray application since viscosity is very less

VG- 20- Used in cold area

VG- 30- Commonly used in India

VG- 40- High grade bitumen used in high traffic areas

Okay. So, lets’ learn about the bituminous layers.

Bitumen road layers

Let’s first look into the road layers to understand bitumen road layers.

bitumen road layers
bitumen road layers

The bitumen road layers come in the surface layer shown in the figure above. The figure below shows that. Bituminous mix consists of aggregate and binder. Aggregate consists of coarse aggregate, fine aggregate and filler less than 0.075mm.

Bitumen road layers
Bitumen road layers
  • Bituminous concrete consists of aggregate and bitumen.
  • Thickness of base course depends on grading of aggregate
  • Dense graded aggregates are provided in base course. That is the permeability will be very less
  • Number of voids should be very less
  • Dense bituminous macadam should be given as a binder course

So, the trip is over. Hope the time you spend for reading about the bitumen for road was worth it.

MUST READ: Road margins- 6 types of road margin in highway

Happy learning!

Intelligent transportation system, TRANSPORTATION ENGINEERING

Intelligent transportation system – Components of Intelligent transportation system

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Intelligent transportation system is a hot topic among all civil engineering subjects that has gained popularity and many countries are successfully implementing it. With the rapidly exploding population, ITS has even become a mandatory technique in all countries. Here, we are going to read through the main components of the intelligent transportation system. We will swim through the benefits of intelligent transportation system in the middle, then to uses and challenges of ITS.

  1. What is intelligent transportation system?
  2. Components of intelligent transportation system
  3. Benefits of intelligent transportation system
  4. Uses and challenges of intelligent transportation system
    1. 1. Use of cameras equipped with automatic number plate recognition(ANPR)
      1. Advantages
      2. Challenges
    2. 2. Speed violation recording cameras
      1.  Advantage
      2. Challenges
    3. 3. Cameras for recording violations of passing through red-lights at intersections
      1. Advantages
      2. Challenges
    4. 4. Equipping the transportation system with GPS
      1. Advantages
      2. Challenges
    5. 5. Use of intelligent routing systems for public transportation passengers
      1. Advantages
    6. 6.  Modern informative systems for offenders
      1. Advantages
      2. Challenges

What is intelligent transportation system?

What is Intelligent Transport System is the first step to dive in the topic. They are advanced applications which, aim to provide innovative services relating to different modes of transport and traffic management and enable various users to be better informed and make safer, more coordinated, and ‘smarter’ use of transport networks. In ITS the information and communication technologies are applied in the field of road transport, including infrastructure, vehicles and users, and in traffic management and mobility management, as well as for interfaces with other modes of transport.

Another answer to the question of what is Intelligent transportation system (ITS) is that, it is the application of sensing, analysis, control and communications technologies to ground transportation in order to improve safety, mobility and efficiency. ITS includes a wide range of applications that process and share information to ease congestion, improve traffic management, minimize environmental impact and increase the benefits of transportation to commercial users and the public in general.

Now, let me walk you through the main components of intelligent transportation system.

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Components of intelligent transportation system

Components of intelligent transportation systems

The main components of intelligent transportation system are,

1. Accurate tracking system
GPS enabled vehicles along with smartphone apps will help citizens to track buses and other vehicles.

2. Electronic timetables
Schedules of bus service should be updated in standard format which can be easily read by people and utilised by softwares.

3. Smart model to predict time of arrival
Transportation studies like that be conducted in IIT Madras, funded by Ministry of Urban Development. should be encouraged to obtain a robust algorithm to predict the arrival time of buses, which is what a citizen needs.

4. Standardisation by regulating authority

This is very important among all the components of intelligent transportation system. An authority should be set up which can standardise various components of the public transport and encourage the use of better and smart IT services in transport sector

5.Smart commuting

Latest information on traffic jams, accidents and ways for navigation

6. Mobile technology

App based technology, incentives for young technical entrepreneurs

7. Smart traffic control

Dynamic controls of traffic signals instead of current static control, automated system.

8. Scalability

The ITS should be easily applicable to 2nd tier cities so that problem of congestion doesn’t arise in the first place

9. Improved and better BRT system enacted with public participation

10. Installing CCTVs on traffic routes and in buses.

11. Creation of flyover and overbridges to eliminate need of traffic lights

12. Electronic payment of fare

13 Traveller’s advisory system like the use of advisory radio, SMS services, internet etc

14. Highway Management Systems: Use ramp metering techniques to measure and regulate by knowing the traffic entering or leaving the highway

15. Emergency Management Systems: To manage any unforeseen emergencies

16. Railroad Crossing: Gives signals about approaching rail junctions

17 Wireless communication System

18. Safe driving Support System

This includes,

a) Right turn collision prevention system

b) vehicle detection system
c) Pedestrian detection system

d) voice guidance

e) display warning

18. Electronic toll payment System

19. Computational technologie

20. Inductive loop detection and sensing technology

21.Freeway management.

Cool! Now how are these components of the intelligent transportation system benefiting transportation? Let’s see below.

Benefits of intelligent transportation system

traffic at night - Components of intelligent transportation systems

The main benefits of intelligent transportation are as follows.

  • Develop (and subsequently renew), a secure and effective revenue collection system – this has formed the backbone of the ITS
  • Develop enhanced operations management capabilities to provide reliable services and deal with disruptions
  • Provide communications for staff security
  • Provide improved passenger information
  • Obtain data for planning, resource optimisation and performance monitoring
  • To assist the achievement of the quantity and quality of the service required in the service contract with the province of Florence

• To generate the trip logs, analysis and reporting required by the province of Florence under the service contract

• To manage the daily operations, on both normal and disrupted state

• To manage the driver vehicle handovers and shift-changes

• To provide the platform for real-time and other information to passengers

• To provide the platform for e-ticketing

• To identify vehicle faults and assist rapid response

• To support demand responsive transport and other non-standard mobility services

• To generate and manage data for post-event analysis, including running time analysis, scheduling, resource optimization, and incident investigation

So, I walked you through the important benefits of intelligent transportation system.

Its time to see the results now.

Uses and challenges of intelligent transportation system

Components of intelligent transportation systems

1. Use of cameras equipped with automatic number plate recognition(ANPR)

Equip the intersections with traffic light crossing violations recording system and video surveillance cameras monitoring traffic flow

Advantages

Cameras are capable of fining any number of offending vehicles simultaneously

Challenges

  • Drivers cover the number plate of their cars daily in order to not to be fined
  • Some drivers who repeatedly pass specific passages try to destroy or damage the cameras and their equipment.

2. Speed violation recording cameras

Fixed cameras equipped with radar technology are assembled to identify and record speed violations

 Advantage

Assured of getting fined through being caught on camera, drivers rarely attempt to drive over the speed limit

Challenges

  • After identifying the locations where the cameras are installed, drivers may attempt to increase their speed in the distances between cameras, and this may cause many disturbances in traffic flow.
  • Due to the weakness of technology, identifying motorcycles is not possible in this system

3. Cameras for recording violations of passing through red-lights at intersections

Cameras are assembled at intersections  to record the red light running violations.

Advantages

A decrease in this kind of violation will have a direct effect in reducing car crashes and capital loss.

Challenges

  • In many intersections, due to the low quality of crosswalks and zebra crossings, it is really hard to determine a threshold running from which enables the driver to be known as an offender
  • As in many intersections, turning left or right is not legally forbidden, it is really a hard job to distinguish the vehicles doing so from the violators.

4. Equipping the transportation system with GPS

Position of the buses and the approximate arrival time of buses to stations can be calculated those who are speeding or using unauthorized routes can be identified

Advantages

  • Reduction of dangerous high speed of buses
  • Decreasing of delay time of journey

Challenges

  • Some drivers try to deactivate the GPS before attempting violation. They cover the GPS with aluminum foil to make it disconnected from the center.
  • Due to the need for a GPRS platform for sending the information to the center, using this system in Tehran is very expensive.
  • Due to the low average educational level of drivers and users of public transportation services, the relevant systematic training for using this system will be needed.

5. Use of intelligent routing systems for public transportation passengers

Passenger can receive information about the journey duration and the best manner of navigation after determining the origin and destination and also specifying the desired transportation mode such as metro, taxi, bus or walking

Advantages

 Decrease in delay of journeys and an increase in productivity.

6.  Modern informative systems for offenders

All fine notifications and notices for a technical test will be informed to the offenders via SMS

Advantages

  • Deliver the fine notifications to the offenders, omitting the process of printing and stuffing envelopes with fine notification
  •  Informing all offenders of their violations in an online manner, and creating a cohesive database of the offenders.

Challenges

  • As the telecommunications system and necessary infrastructure have not been completely developed, some problems in sending the SMS to offenders have been occasionally observed.
  •  Informative limitations such as length of words in SMS.

That’s it about ITS.

Continue learning!

MUST READ: Basic of civil engineering; Simple and in-depth guide

Hydrauilics, Irrigation

Furrow Method of Irrigation – Definition, Types and Advantages

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The furrow method of irrigation is a method of laying out water channels in such a way that gravity provides just enough water for suitable plants to grow. It is typically formed through the deliberate placement of ridges and furrows. The furrow method of irrigation is one of the surface irrigation methods. Straight furrows and contour furrows are subdivisions. I will explain the important details about each of them. Also, we will find out the types methods and advantages of furrow irrigation in the blog.

So, without any due let’s look into the basics of the furrow method of irrigation.

  1. What is the Furrow Method of Irrigation?
  2. Furrow spacing for crops
  3. Types of Furrow Method of Irrigation
    1. Straight furrow
    2. Contour furrow
  4. Construction of furrow method of irrigation
  5. Advantages of furrow irrigation

What is the Furrow Method of Irrigation?

In this section, you will get the answer to what is furrow irrigation. The furrow method of irrigation is a method of laying out water channels in such a way that gravity provides just enough water for suitable plants to grow. It is typically formed through the deliberate placement of ridges and furrows.

Furrow Method of Irrigation- One of the Types of Surface Irrigation
Furrow Method of Irrigation- One of the Types of Surface Irrigation
  • The furrow method of irrigation is very much used for row crops like maize, jowar, sugarcane, cotton, tobacco, groundnut, potatoes etc.
  • In this method, only one-half to one-fifth of the surface is wetted, and thus evaporation losses are very much reduced
  • A furrow consists of a narrow ditch between rows of plants.

Let’s dig deep now.

Basically, furrow lengths range from 3m or less for gardens to 500 m for field crops, with 100 to 200 m being the most common. If the furrows are too long, deep percolation losses and soil erosion near the upper end of the field may occur. Furrows are typically provided with slopes that range from 0.2 to 6%. Accordingly, to ensure surface drainage, a minimum furrow grade of 0.05% is required.

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Furrow spacing for crops

Furrow spacing for corn, potatoes, sugarcane, and other row crops is determined by the proper spacing of the plant rows, with one irrigation furrow provided for each row. But in the case of In orchard irrigation, furrow spacing is kept between 1 and 2 metres. If the spacing is kept more, it is essential to check the distribution of moisture after each watering by auger boring.

Generally, It is more effective if the spacing is increased. Accordingly, if the spacing is maintained, it is crucial to auger bore after each watering to assess the moisture distribution. Furrow depths in low-permeability soil can range from 20 to 30 cm. When irrigating root crops, it is critical to have furrows that are deep enough and streams that are small enough that water does not come into contact with the plant. Generally, furrows for row crops like cotton, tobacco, and potatoes are typically 25cm wide and 8 to 10cm deep.

That’s it about the general details of the furrow method of irrigation. Let me show you the types now.

ALSO READ: Check flooding and Border strip methods of irrigation

Types of Furrow Method of Irrigation

Depending upon the alignment, furrows may be of two types.

  1. Straight furrow
  2. Contour furrow

Straight furrow

  • Straight furrows are used where the land slope is nominal.
  • These are aligned more or less along straight lines parallel to each other and along the slope of the land.
  • These are normally adopted where the slopes do not exceed 0.6%.

Contour furrow

  • Contour furrows are practically laid along the contours. Therefore, these are not straight but are curvilinear in the plan.
  • With contour furrows irrigation, the direction of flow is across a sloping field rather than down the slope to reduce water velocity.
  • The furrows are laid out with enough grade to carry the irrigation streams. Head ditches are run across the slope or downhill using drop structures as needed, to feed the individual furrow.
  • The contour furrows method can be successfully used in nearly all irrigable soil.
  • Light soils can be irrigated successfully across sloped up to 5 per cent. Where the soils are stable and will not be cultivated, slopes up to 20 per cent can be irrigated by contour furrowing.

ALSO READ: Rainwater Harvesting Methods: Everything You Need To Know

Stored the details in the brain, right? Let me walk you through the construction method of furrows now.

Construction of furrow method of irrigation

Furrow Irrigation
Furrow Irrigation
  • Furrows are made before planting, at the time of planting or after the plants have grown large enough not to be covered up.
  • The time of furrowing depends upon the crop grown and the method of planting used.
  • Often young plants are irrigated by small furrows until a good root system is developed. Thereafter, the furrow is made larger.
  • The furrows at any stage must be large enough to carry the water needed for irrigation.
  • In most soils, crops are grown on the top of the ridge while in deep sand, it is better to have the seeding near the bottom of the small furrow.
  • An alternate method specially adapted to sandy soils is to transplant vegetables in the furrow, irrigate it once or twice and then establish furrows between the rows after plants have grown larger.
  • Furrows are made with various cultivating tools depending on the type of crop to be grown.
  • Large furrows are normally made with a double mould board plough or lister.
  • A wooden plough with furrower attachment can also be used in place of listers. Disc-drum corrugator furrower is very useful to make small size furrows in sandy soil.

ALSO READ: Concept of green building- 4 comprehensive concepts easy read!

Time to have some positivity. The advantages of the furrow method of irrigation are given in the next section.

Advantages of furrow irrigation

irrigating plants -Furrow method
Irrigating plants

In furrow irrigation, water contacts only 1/5 to ½  of the land surface, reducing pudding and crusting of the soil. Losses due to evaporation are also reduced. Evaporation losses are also reduced. Previously, cultivation is possible in heavy soil and can be adapted to use without erosion on a wide range of natural slopes by carrying furrows across a sloping field rather than down the slope. It is especially beneficial for crops that have been harmed by water contact. Similarly, Labor requirements for land preparation and irrigation are drastically reduced. Moreover, field ditches do not waste any land.

Liked the concept of the furrow method of irrigation? Let me know your thoughts in the comments.

MUST READ GOOGLE 1st RANKING POST: Road margins- 6 types of road margins in highway

Happy learning!

architectural finishes, GFRC

Glass Fibre Reinforced Concrete- Fiberglass reinforced concrete Advantages

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Glass Fibre Reinforced Concrete or GFRC is made up of portland cement, fine aggregate, water, acrylic copolymer, alkali-resistant glass fibre, reinforcement, and additives. Glass fibre-reinforced concrete or GFRC is a type of fibre-reinforced concrete. The glass fibres used in Glass Fibre reinforcement concrete give this distinctive compound its strength. Alkali-resistant fibres serve as the primary tensile load-carrying member, while the polymer and concrete mix holds the fibres together. It assists in the transfer of load from one element to another.

These are mainly used in exterior building façade panels and as architectural precast concrete. Somewhat similar materials are fibre cement siding and cement boards. They consist of high-strength, alkali-resistant glass fibre embedded in a concrete matrix.

In this form, both fibres and matrix retain their physical and chemical identities, while offering a synergistic combination of properties that cannot be achieved with either of the components acting alone.

Let’s get into each of them now.

  1. Glass Fibre Reinforcement Concrete – Ingredients
    1. Cement
    2. Fine Aggregates
    3. Polymers
    4. Water
    5. Glass Fibre
    6. Other Admixtures
  2. Fibre Glass reinforced concrete – Casting Process
    1. Spray-Up
    2. Premix
    3. Hybrid method
  3. Glass Fiber Reinforced Concrete Advantages
    1. Low weight and high strength of Glass Fiber Reinforced Concrete
    2. Freedom of shape of Glass Fiber Reinforced Concrete
    3. 3. Durability
    4. The appearance of Glass Fiber Reinforced Concrete
    5. Environment
  4. Applications of Glass Fibre Reinforced Concrete
  5. Conclusions

Glass Fibre Reinforcement Concrete – Ingredients

The main ingredients used in Glass Fibre Reinforced Concrete are as follows

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Cement

Fine Aggregates

  • The fine aggregates usually should be river sand.
  • The fine aggregates used passed through a 4.75mm sieve and had a specific gravity of 2.68. The fine aggregates belonged to Zone II according to IS 383. 2

Polymers

  • Acrylic polymer is typically preferred over EVA or SBR polymers for GFRC. Acrylic is non-retweetable, so once dry, it will not soften or dissolve, nor will it yellow from exposure to sunlight.
  • The solids content of most acrylic polymers used in GFRC ranges from 46% to over 50%.
  • Typically, the polymer dose is 4%- 7% solids by weight of cementitious material depending on the design.

Water

Ordinary tap water which is safe and potable for drinking and washing was used to produce the concrete

Glass Fibre

  • Glass fibre, also known as fibreglass is made from extremely fine fibres of glass.
  • It is a lightweight, extremely strong and robust material. Glass fibre, the most popular of the synthetics, is chemically inert, hydrophobic, and lightweight.
  • They are manufactured as continuous cylindrical monofilaments that can be cut to specific lengths or cut as films and tapes before being formed into fine fibrils with rectangular cross-sections. Glass fibres that can withstand alkalis are a crucial part of GFRC. When using the spray-up method of casting, your sprayer will automatically cut the fibres and add them to the mixture as you apply it. If you’re casting with a premix or a hybrid method, you’ll have to mix the fibres along with other ingredients.
  • Although fibre content varies, it usually ranges from 3% to 7% of the total cementitious weight. High fibre content increases strength but decreases workability. Unlike most concrete mix design ingredients, fibres in GFRC are not calculated as a percentage of dry cementitious weight. Instead, they are calculated as a percentage of total weight. As a result, calculating fibre load in GFRC mix designs becomes quite complicated. Glass fibre, when used at a rate of at least 0.1 per cent by volume of concrete, reduces plastic shrinkage cracking and subsidence cracking over steel reinforcement.

Other Admixtures

  • Other ingredients to consider include pozzolans (such as silica fume, metakaolin, or VCAS) and superplasticizers.

So, we dug deep into the inside of Glass fibre-reinforced concrete. Next, let me walk you through the advantages of GFRC.

Fibre Glass reinforced concrete – Casting Process

GFRC is typically cast using two methods ie: spray up and premix. Let’s take a quick look at both, as well as a less expensive hybrid option.

Spray-Up

The fluid concrete mixture is sprayed into the forms, similar to shotcrete. The process employs a specialised spray gun to apply the fluid concrete mixture while simultaneously cutting and spraying long glass fibres from a continuous spool. Spray-up produces very strong GFRC due to the high fibre load and long fibre length, but the equipment is very expensive.

Premix

Premix incorporates shorter fibres into the fluid concrete mixture before it is sprayed or poured into moulds. Spray guns for premix do not require a fibre chopper, but they can be very expensive. Premix has less strength than spray-up because the fibres are shorter and distributed more randomly throughout the mix. The cost and strength are comparatively lesser than the spray-up method.

Hybrid method

An inexpensive hopper gun can be used to apply the face coat while a handpicked or poured backer mix is used to create GFRC using a hybrid technique. A thin, fibre-free face (referred to as a mist coat or face coat) is sprayed into the moulds, and the backer mix is then packed in by hand or poured in, much like ordinary concrete. This is the method most concrete countertop manufacturers employ. This is an inexpensive way to get started. However, it is critical to carefully create both the face mix and the backer mix. This is to ensure similar consistency and makeup, as well as to know when to apply the backer coat. While doing so the backer coat can adhere properly to the thin mist coat without tearing it.

This method is comparatively inexpensive when compared to the r two methods. The face and backer mix are applied at different times ensure to have similar make-up of mixes to prevent curling

Glass Fiber Reinforced Concrete Advantages

The main advantages are,

Glass fibre reinforced concrete
Glass fibre reinforced concrete

Low weight and high strength of Glass Fiber Reinforced Concrete

  • Self-weight of structures decreases when Glass Fiber Reinforcement Concrete (GFRC) is used and demands on foundations are reduced.
  • GRC cladding is suitable even for very high-rise buildings and offers good performance under seismic loading.

Freedom of shape of Glass Fiber Reinforced Concrete

  • GRC is easily moldable into a wide range of shapes, including intricate grilles, panels with a double curvature and 3-D objects.
  • The high freedom of shape permits the production of structurally very efficient elements.
  • Easily cast, it can produce items with very fine details and reproduce very complex features and elements of both modern and historic buildings.

3. Durability

  • Basic reinforcement is non-ferrous and the GRC products are not susceptible to corrosion as in traditional reinforced concrete.
  • Low permeability and a very slow rate of carbonation offer protection against the corrosion of steel in adjacent reinforced concrete.
  • GFRC has an inherently high resistance to extreme exposure conditions (freeze/thaw, fire etc.)

The appearance of Glass Fiber Reinforced Concrete

  • An extremely wide range of attractive surface finishes is available.
  • It satisfies the highest requirements for an aesthetic appearance of new structures and is capable of matching the colour and texture of surfaces of existing buildings.
  • Durable and brightly coloured surfaces with enhanced self-cleaning can be achieved in a variety of textures and shapes.

Environment

  • The relatively low weight of GRC products reduces CO2 emissions associated with their transport.
  • There are no Volatile_organic_compounds or other pollutants emitted from the material itself, neither in production nor in use.
  • GRC is fully recyclable into concrete and other applications.
  • In addition, the photocatalytic E-GRC reduces directly and significantly the concentration of pollutants in the surrounding air, leading to a better quality of the environment.
  • This is good especially in congested urban centres and at a minimal additional cost.

Also read: 3 d Printing buildings |Concrete Printing & Contour Crafting Methods Full Guide

Now, how about a quick glance through the applications?

Applications of Glass Fibre Reinforced Concrete

Glass Fiber Reinforced Concrete - Fascia
GFRC Building

Due to its versatility the range of GFRC is growing.

  • All the categories of buildings have been constructed using GFRC
  • Small, simple and unsophisticated items for everyday use are made using GFRC on a large-scale
  • Architects prefer GFRC to fulfil high structural complexity, size of construction elements, and freedom of shape to achieve spectacular appearance, durability and the highest quality
  • Positive environmental performance

That’s it. Time to sum up.

Conclusions

  • GFRC has a large scope of application and research and development is going on
  • It is a very versatile material and the freedom of shape makes it the number one choice by architects
  • Glass fibre reinforced concrete is used from small scale household products to large-scale buildings of structural complexity

So, how is our buddy GFRC? Let me know your thoughts in the comments.

Also read: Shotcrete – An overview| Shotcrete vs Gunite

Happy learning!

BUILDING CONSTRUCTION

Types of Cracks in Building- 14 Building Cracks Types- Causes & Prevention

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Types of cracks in building varies with the type of building and construction. Cracks are always a hint of the stability and strength of the structure. Here we are going to find out the main causes and the remedial measures to tackle each of them.

  1. Main causes of different types of cracks in building
    1. Thermal Movement
      1. Preventive Measures for thermal movement
    2. Chemical Reaction
      1. Preventive Measures for the types of cracks in building
    3. Shrinkage
      1. Preventive Measures
    4. Building cracks types generated due to quantity of Cement
      1. Preventive Measures
    5. Earthquake
      1. Preventive Measures
    6. Vegetation
      1. Preventive Measures for the types of cracks in building
    7. Bad construction practices cause some types of cracks in building
      1. Preventive measures
    8. Corrosion Cracks
      1. Preventive measure
    9. Types of cracks in building due to elastic deformation
    10. Foundation movement and settlement of soil
    11. Permeability of concrete
    12. Poor Workmanship
    13. Lack Of Maintenance
    14. Types of cracks due to structural design

Main causes of different types of cracks in building

There are different types of cracks in building depending on the causes. Let’s jump right into one at a time.

  • Thermal Movement
  • Chemical Reaction
  • Shrinkage
  • Types of cracks generated due to cement quantity
  • Earthquake cracks
  • Vegetation
  • Building crack types due to bad construction practices
  • Corrosion cracks
  • Types of cracks in building due to elastic deformation
  • Foundation movement and settlement of soil
  • Permeability of concrete
  • Poor workmanship
  • Lack of maintenance
  • Type of cracks due to structural design failures

Thermal Movement

  • This is a common cause of cracks in building.
  • Thermal movement is the expansion and contraction with changes in temperature regardless of the structure’s cross-sectional area.

Preventive Measures for thermal movement

Joints need to be built like construction joints, expansion joints, control joints and slip joints.

Chemical Reaction

  • There are chances of chemical reactions to occur because of the materials used to build the concrete or materials.
  • Cracks might develop in concrete periodically as the result of developing expansive reactions between aggregate having active silica and alkalis from cement hydration, admixtures or external sources.

Preventive Measures for the types of cracks in building

If sulphate content in soil is greater than 0.2 percent or in ground water exceed 300 ppm, leverage very dense concrete and either increase richness of mix to 1:1/5:3.

Shrinkage

  • Majority of the building materials expand when they absorb moisture from the atmosphere and shrink when they become dry.
  • In this type of cracks in the building, the main causes of cracks are the excess water. The amount of water needed in the mortar mix causes shrinkage.
  • Shrinkage cracks may also be due to heat of hydration and lack of curing.

Preventive Measures

Use minimum quantity of water for mixing cement concrete or cements mortar according to water to cement ratio .

Building cracks types generated due to quantity of Cement

Building cracks types : Due to cement quantity
Building cracks types : Due to cement quantity

The proportion should be such that the cement in the mix is optimum. Higher the cement, greater the shrinkage/drying.

Preventive Measures

Do not use excessive cement in the mortar mix.

Earthquake

Crack happens because of the rapid shift in lower layer of the earth.

Preventive Measures

Build the foundation of building on firm ground. Tie up the building at base level, door level and roof level with connecting beams.

We covered the first five types of cracks in building. Good to have you here. Let’s move on to the remaining.

Vegetation

  • Due to the expansive action of root growing under the base, fast growing trees may often cause cracks in walls in the area around the walls.
  • Also, due to moisture contained by roots, cracks occur in clay soil.

Also read: Concept of green building- 4 comprehensive concepts easy read!

Preventive Measures for the types of cracks in building

Do not plant trees too close to the house. If they start growing in or near walls, remove any saplings from the trees as quickly as possible.

Bad construction practices cause some types of cracks in building

Building crack types : Bad construction practice
Building crack types : Bad construction practice
  • Owing to indifference, carelessness, greed or incompetence, there is a general lack of good building practices
  • It is certainly vital for the building agency and the owner to ensure high quality material selection and good construction practices for a safe building.

Preventive measures

At the time of construction, careful inspection and use of materials of high quality is required.

Corrosion Cracks

  • The pH level of the concrete under normal conditions is high (above 12.5).
  • The high concrete pH allows for the formation of an inactive layer of ferric oxide around the reinforcement, avoiding corrosion.
  • The reinforced steel has two important causes of corrosion:
  1. Chloride penetration

2. Carbonation.

  • Penetration of chloride decreases the concrete’s pH level as oxygen, chlorides, and moisture both enter the concrete.

Preventive measure

As per IS 456-2000, use acceptable covers. When mixing concrete, use potable water.

Types of cracks in building due to elastic deformation

  • In different sections, unevenly loaded walls experience enormous variations in stress that cause cracks in walls.
  • Different shear stresses in these materials result in cracks at the junction when two building materials like masonry, concrete, steel, etc.
  • with broadly different elastic properties are constructed together under the impact of load.
  • In a building’s structural elements, dead and living loads cause elastic deformation.
  • The amount of deformation depends significantly on the material’s elastic modulus, the loading magnitude and the component dimensions.

Foundation movement and settlement of soil

  • Shear cracks occur in the base due to enormous differential settlement. Structures built on expansive soils that are susceptible to swelling due to changes in soil moisture content are highly susceptible to cracking when absorbing moisture and shrinking when drying.

Permeability of concrete

  • The process of corrosion in concrete begins with the penetration of many aggressive agents and is a significant cause of wall cracks.
  • Essentially, the ability of concrete to withstand weathering action, chemical attack or some other degradation mechanism is dictated.
  • Low permeability is thus the primary factor in concrete resilience.
  • Concrete permeability, water-cement ratio, curing, air voids due to poor compaction, use of admixtures, micro-cracks due to loading, cyclic exposure to thermal variations, and concrete ageing are influenced by several factors.
  • Cement mixture permeability is a feature of the water-cement ratio due to high-quality materials, sufficient proportioning, and good construction practice.
  • Concrete permeability is a direct result of the interconnection and porosity of the cement paste pores.

Poor Workmanship

Building cracks types due to poor workman ship
Construction worker building a structure
  • The lower mixing of building materials such as sand, cement and concrete, creates cracks on walls, slabs, beams, etc.
  • Bad workmanship typically results from a lack of proper oversight, incompetence, neglect, and many others, or a mixture of all of these.

Lack Of Maintenance

  • It is necessary to take good care of your home at all times, and this can be achieved by doing routine maintenance work.
  • This means the foundation of the building remains intact and it also contributes to its lifetime.

Time to meet the last cause. Its the structural design of the structure.

Types of cracks due to structural design

  • Poor or bad structural design and specifications are another striking causes of the cracks in buildings made of majorly concrete.
  • The designer needs to consider all the environmental aspects which include soil investigations, this will enable the designer to come up with a properly robust design of the foundation.

In nutshell, each type of cracks have to be analysed and proper treatment methods and retrofits have to be adopted to restore the structure to last long.

Hope the article could educate you on the types of cracks in building, the main causes and preventive measures. Let me know if you have any doubts in the comments.

Happy learning!

bridges, TRANSPORTATION ENGINEERING

Types of Bridges – Top 7 Bridge Design Types and Principles

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Types of Bridges in civil engineering can range from modest constructions to massive, eye-catching pieces of art – and everything in between. A bridge serves its sole purpose as long as it transports us across a gap. The required passage may be for a road, train, pedestrians, canal, or pipeline. A river, a road, a railway, or a valley may be crossed. Types of bridges are an important classification in civil engineering. In today’s blog, we are going to learn about different types of bridges in detail.

Types of bridges and Bridges design types in civil Engineering

The types of bridges are broadly classified as follows on the basis of form and type of superstructure

  • Arch Bridge
  • Beam bridge
  • Cantilever bridge
  • Suspension bridge
  • Cable-Stayed Bridge
  • Tied-Arch Bridge
  • Truss Bridge

Let’s dig deeper into each of the types now.

Arch Bridge – Types of Bridges

Arch Bridge
Arch Bridge
  • A dead load of a bridge is the weight of the bridge itself, plus the weight of whatever it is carrying (the live load). The forces of load and gravity, which would otherwise send a bridge sliding downhill, are used to hold an arch bridge aloft instead. 
  • An arch bridge works by channelling gravity’s downward force into the structure’s centre — toward a central stone known as the keystone — rather than straight down.
  • Compression is the principle that allows the arch below to support the surface, or deck, above it.
  • Temperature changes can destabilise fixed arch bridges, hence the arch design is occasionally changed with hinges at each base and even the span’s centre.
  • This allows longer arch bridges to adjust to material expansion and contraction when temperatures fluctuate.

Also read: Bridge components explained – Types and functions.

Beam Bridge – Types of bridges

The beam bridge was the first form of bridge ever created due to its simplicity. It is still the most cost-effective to construct. All you need is a crossbeam that spans the gap and is supported at each end by an abutment. A girder bridge is a form of beam bridge that uses steel girders for reinforcement. 

beam bridge
beam bridge
  • Gravity presents a greater issue when creating a bridge since, unlike a building, the majority of the space beneath it is empty.
  • To resist gravity and bear the full load, a beam bridge might be supported merely by two abutments, one at each end.
  • But there’s a catch with beam bridges: the longer a bridge is and the more people, cars, and other objects it carries, the heavier the entire weight becomes.
  • The more abutments on a beam bridge are spaced apart, the less stable the structure becomes. 
  • You may make a long, stable bridge by putting supports in the middle, known as piers or stanchions, and connecting sections between them.
  • The Yolo Causeway in Sacramento, California, is 3.2 miles long, and the Lake Pontchartrain Causeway in Louisiana is 24 miles long.
  • The force of compression drives the weight inward onto piers in the middle of the bridge in beam bridges.
  • Simultaneously, the tension pulling or stretching force pulls the load outward toward the bridge’s abutments on both ends.

Also read: Highway Engineering- Definition, Importance and Construction Details

Cantilever Bridges Types

Cantilever construction is used on some bridges.

  • This design uses a vertically anchored pillar to support a horizontal deck that extends out from one or both sides across the span.
  • Both the above and below are frequently used to support the load.
  • A good example of cantilever construction is a diving board or platform.
cantilever bridge
cantilever bridge

Suspension Bridge Types

Suspension bridges are exactly what they sound like: they’re supported by vertical pillars or pylons that are linked by suspension cables.

Suspension bridge
Suspension bridge
  • Smaller, vertical suspenders are attached to these main cables and use tension to hold the bridge deck up.
  • Tension is the main force that sustains these types of bridges.
  • Despite the fact that the original suspension bridges were composed of simple ropes supporting wooden planks, the suspension technique now allows for vast spans across wide canals.
  • However, because these bridges are only attached to the ground in a few locations, they might shake when heavy traffic passes beneath them.
  • Vibrations can be caused by wind or movement across a bridge.
  • When these reach a specific frequency, resonance occurs, which is the same mechanism that causes the glass to shatter when a trained vocalist hits a high enough note.
  • Bridge crossings can be disrupted and collapsed if vibrations are strong enough. 
  • Torsion, a twisting force commonly generated by external variables such as wind, can also impact these bridges, causing unsafe movement.
  • Travelers can be thrown off a bridge if the surface twists significantly while they are on it.
  • While torsion causes tension in a vertical plane, shear causes stress in a horizontal plane.
  • It occurs when opposing environmental pressures act on a single, fixed component of a bridge, causing it to break like a stick between two hands.

Also read: Cofferdams – Types & Construction methods

Cable-Stayed Bridge

  • A suspension bridge with a cable-stayed bridge connects the crossbeam or bridge deck directly to pillars or towers.
  • There is no main cable, only a slew of vertical suspenders attached to the tower’s summit.
  • Tension is used by these suspenders to keep the bridge deck solid and in place.
Cable Stayed Bridge
Cable Stayed Bridge

Tied-Arch Bridge

  • The qualities of an arch bridge and a suspension bridge are combined in a tied-arch bridge.
  • It supports an arched structure with horizontal force from both sides, similar to a normal arch bridge.
  • Instead of supporting the building from below, the arch rises over the road, with vertical ties descending to provide additional decking support. 
  • Because they resemble a bow from the side, these are sometimes known as bowstring bridges.
  • This bow supports the weight and keeps the bridge stable by combining the tension of its vertical cables with the compression of the arch.
Tied arch bridge
Tied arch bridge

Also read: Golden Gate Bridge: Design and 2 Main Issues

Truss Bridge

  • The load on a truss bridge is distributed across a succession of tiny sections that are joined together.
  • Bridge trusses are typically formed by structural beams for smaller bridges or box girders for bigger bridges, and are joined in a sequence of triangles by welded or riveted joints. 
  • The bridge is held up by tension from vertical steel or timber supports, while compression from diagonal truss supports adds stability by directing the weight toward the centre, similar to an arch.
Truss bridge
Truss bridge

That’s it about the main types of bridges. Each of these has advantages and disadvantages. We need to decide on the type of bridge based on the requirements.

Let me know in the comments if you need any further information.

Happy learning!