As we already know that by definition irrigation is an activity in which we provide water to the land or soil. The basic purpose of applying water to the soil is to grow agricultural crops or maintain a landscape. It  is necessary in areas where the natural rainfall is not sufficient to suffice the basic needs of crops. Irrigation is done by various methods, of course we will not consider them in this post but most important of all the structures in irrigation is a canal. 

An irrigation canal is a waterway, often man-made or enhanced, built for the purpose of carrying water from a source such as a lake, river, or stream, to soil used for farming or landscaping.

It can be dug into the ground and then filled with water, or an existing stream can be widened in a process called "canalization," and diverted as appropriate to provide maximum efficiency.

One of the difficulties with irrigation canals is providing a reliable flow of water.

Here are some of the pictures that will help you in understanding what really the irrigation canal is;

What is Irrigation Canal

Irrigation Canal

Construction of Irrigation Canal

The overall objective for the design of bituminous paving mixtures is to determine, within the limits of the project specifications, a cost-effective blend and gradation of aggregates and bitumen that yields a mix having the following properties:
Design of Asphalt Pavement, Bitument Pavement

(a) Sufficient bitumen to ensure a durable pavement;

(b) Sufficient mixture stability to satisfy the demands of traffic without distortion or displacement;

(c) Sufficient voids in the total compacted mixture to allow for a slight amount of bitumen expansion due to temperature increases, without flushing, bleeding and loss of stability;

(d) A maximum void content to limit the permeability of harmful air and moisture into the mixture and the layers below; and

(e) Sufficient workability to permit efficient placement of the mixture without segregation and without sacrificing stability and performance.

Also, for wearing course materials, the mix should

(i) Have sufficient aggregate texture and hardness to provide good skid resistance in bad weather conditions,

(ii) Produce an acceptable level of tyre/road noise, and

(iii) Provide a surface of acceptable ride quality.

Ultimate pavement performance is related to durability, impermeability, strength, stability, stiffness, flexibility, fatigue resistance, and workability.

The goal of mix design is to select a unique design bitumen content that will achieve an appropriate balance among all of the desired properties.

Selection of the aggregate gradation and the grade and amount of bitumen can be accomplished by two general methods: a standard ‘recipe’ approach, or an engineering design approach. 

A beam is a long slender member, a 2d element in structure having relatively longer span than the depth. Beam is designed to carry the bending moment and the shear forces if any. Based on the supports of the beam, Following are some of the classification of the beam.

Classification based on supports

The following are the important types of beams :-
a) Cantilever beam
b) Simply Supported beam
c) Overhanging beam
d) Fixed beams
e) Continuous beams
f) Propped Cantilever beam

Cantilever Beam

A beam which is fixed at one end and free at the other end is known as cantilever beam, Or from statics point of view a beam with fixed support at one end resisting all the vertical, horizontal and bending moment produced as a result of loading of the beam and is free at the other end is cantilever beam. The beam is shown ;-

Cantilever beam with fixed supports 

Simply Supported Beam

As the name suggests a beam which is supported or resting freely on supports at its both ends is known as simply supported beam or from mechanics point of view, a beam with both hinge support resisting horizontal and vertical forces and roller support fixing only one vertical force is known as a simply supported beam as shown ;-

Simply Supported Beam 

Overhanging beam

If the end portion of the beam is extended beyond the support such a beam is known as overhanging beam. Mostly in overhanging beam one support is Hinge support while other is roller support having one end as free like a cantilever. The shape of the beam is shown :-

Overhanging beam 

Fixed Beam

A beam whose both ends are fixed or built-in walls, is known as fixed beam. A fixed beam is also known as built-in or encastred beam.  A fixed beam usually have reinforcement that is going through the beam into the column as shown.

Fixed end beams 

Continuous Beams 

A beam which is provided more than two supports or is continuous over more than two supports is known as continuous beam. Usually in frame structure a continuous beam is used which have both positive and negatives moments you will be able to calculate later on.

Continuous Beams

Propped Cantilever Beam

A propped Cantilever beam is a little modification of the cantilever beam, if the free end of the cantilever beam is place on a roller support than the resultant beam will be propped cantilever beam as shown ;-

Propped Cantilever Beam

A beam transfers the load to the supports that in actual might be a column or a wall which in turn transfers the load to the foundation.

Different Type of Structure / Beam Supports

The supports are actually the conditions in which this load is distributed. The supports that are normally used in a beam are ;-

a) Roller Support
b) Hinge or Pin Support
c) Fixed Support

Roller Support

Roller Support provides only one direction resistive force to the beam. It is like a beam placed on a wall, it has one reaction force.

Hinge or Pin Support

A hinge or a pin support provides two dimensional resistive forces that might be in horizontal and vertical dimensions, thus it have two reaction forces as shown ;-
A practical example of a roller support is a Bridge Abutment in which a beam seat is designed on which the girder lies in such a way that only moment can be produced with no horizontal and vertical displacement is allowed.

Fixed Support

When the support provides resistance to the forces as well as the moment than this support is known as a fixed support. It have 3 reactions as shown ;-

To know more on how to find these reaction supports click the link 

The algebraic sum of the vertical forces at any section of a beam to the right or left of the section is known as shear force. It is briefly written as S.F. 

The algebraic sum of the moments of all the forces acting to the right or left of the section is known as bending moment. It is written as B.M. 

Shear Force and Bending Moment Diagram

The members of rigid frames and beams may be subjected to shear forces and bending moments as well as axial forces under the action of external loads. 
The determination of these internal forces and moments (stress resultants) is necessary for the design of internal forces and moments that may develop in beams and the members of plane frames, under the action of coplanar systems of external forces and couples. 

Beams are structural members designed to support loadings applied perpendicular to their axes.

In general, they are long and straight and have a constant cross-sectional area. The actual design of a beam requires a detailed knowledge of the variation of the internal shear force designated by V and bending moment designated by M acting at each point along the axis of the beam. 

A shear force diagram is one which shows the variation of the shear force along the length of the beam. And a bending moment diagram is one which shows the variation of the bending moment along the length of the beam. 

How the Shear Force and Bending Moment Diagram is Drawn

Shear force and bending Moment Diagram is drawn by the method of Sections, in which a section is cut at various distances from the supports to find the internal shear and bending moment at that section. In such a way along the length of the member the forces are known and are then plotted on a graph as shown in the above graph. 

To know more about how to draw shear force and bending moment proceed to 

Foundation substructures are structural members used to support walls and columns to transmit and distribute their loads to the ground.

“Footing is the lowest part of the structure that distributes the load on a larger area to avoid any shear or axial failures of the structure”

What is foundation?

Design Criteria of Foundations 

For proper transmission of the load the substructures must be designed
To prevent excessive settlement
To prevent rotation
To minimize differential settlement.

In addition, it should be designed in such a way that
The load bearing capacity of the soil is not exceeded.
Adequate safety against sliding and overturning is assured.

Settlement of Foundation

Cumulative floor loads of a building, a bridge, or a retaining wall are supported by the foundation substructure in direct contact with soil. The soil underneath the substructure becomes compressed and deformed during its interaction with the substructure.

This deformation is the settlement that may be
Permanent due to dead loads
May be elastic due to transition live loads.

The amount of settlement depends on
Type of soil,
The load intensity,
The ground water conditions,
The depth of the foundation below ground level.

Differential Settlement 

“If the bearing capacity of the soil is different under the different parts of the foundation of the same structure than differential settlement occurs.”

 Differential settlement will cause uneven settlement that will overstress the supports of the structural systems.

Due to excessive settlement additional bending and tensional moments in excess of the resisting capacity of members will be produced that would lead to excessive cracking and failures.
If all the building undergoes to even settlement, little or no overstressing occurs.
Types of Foundation

The following are the common type of foundations usually used for a building or structure :-

Isolated Spread Footings 

Mostly in a frame structure (having beams and columns) the foundations for a column is isolated or spread footing. These footings are used to carry loads of individual columns. Isolated spread footing may be in any shape like rectangular, square or circular depending upon design requirement.
The footing may be of uniform thickness, stepped, or even have sloped top and reinforced in both directions.

Isolated / Spread Foundation

These are the most economical type of foundation, when columns are spaced at relatively long distance.

Wall Footings or Strip Footing

Mostly when the walls are load bearing, as in the case of flat plate slab when the slab is directly resting on the walls than the load of such walls is transmitted using wall footing or strip footing. It is in limited width and continuous slab strip along the length of the wall.
“The critical section for bending is located at the face of the wall”
Strip or Wall Foundation

“The main reinforcement is placed perpendicular to the wall direction”
Wall footings may have uniform thickness, be stepped, or have sloped top.

Combined Footing 

In case of closely spaced columns it is more economical to combine their footings in such a way that footings of two or more columns are combined in a rectangular or trapezoidal plan.

The combined footing becomes necessary in situations where a wall column has to be placed on a property line that may be common in urban area. Under such conditions, an isolated footing may not be suitable since it would have to be eccentrically loaded. It is more economical to combine the exterior column footings with an interior column footing.
Combined Foundation

Strap Footing or Cantilever Footing 

For eccentric column load at the exterior column (possibly located along the property line) the effect of the bending moment produced is transferred to the interior column footing using a strap beam.
Strap Foundation - Cantilever Foundation

Mat, Raft or Continuous Footing

In case when the soil conditions are poor and a pile foundation is not economical than the load of the columns is transferred to a mesh or a mat supporting all of the columns.
Matt or Raft Foundation

Pile Foundation 

This type of foundation becomes essential when the supporting soil consists of poor layers of material to an extended depth such that an individual or mat foundation is not feasible.

Pile Foundation 

Soil mechanics originated several decades ago under the pressure of necessity. As the practical problems involving soils broadened in scope, the inadequacy of the scientific tools available for coping with them became increasingly apparent.

Efforts to remedy the situation started almost simultaneously in the United States and in Europe, and within short period they produced an impressive array of useful information. 

The initial successes in this field of applied science were so encouraging that a new branch of structural analysis appeared to be in the making. As a consequence, the extent and profundity of the theoretical investigations increased rapidly, and experimental methods were developed to a high degree of refinement. Without the results of these painstaking investigations a rational approach to the problems of earthwork engineering could not have been attempted.

Soil Mechanics in Engineering Practice Third Edition by Karl Terzaghi, Ralph B. Peck 

Unfortunately, the research activities in soil mechanics had one undesirable physchological effect. They diverted the attention of many investigators and teachers from the manifold limitations imposed by nature on the application of mathematics to problems in earthwork engineering. As a consequence, more and more emphasis has been placed on refinements in sampling and testing and on those very few problems that can be solved with accuracy.

Title of the Book

Soil Mechanics in Engineering Practice
Third Edition

Authors of the Book 

Karl Terzaghi, Ralph B. Peck, Gholamreza Mesri

Contents of the Book

Part 1 : Physical Properties of Soil
Chapter 1 Index Properties of Soil
Chapter 2 : Soil Exploration
Chapter 3: Hydraulic and Mechanical Properties of Soil
Part II Theoratical Soil mechanics
Chapter 4: Hydraulics of Soil
Chapter # 5 : Plastic Equilibrium in Soil
Chapter # 6: Settlement and Contact Pressure
Chapter # 7: Ground Improvement
Chapter # 8: Earth Pressure and Stability of Slopes
Chapter # 9 : Foundation
Chapter # 10: Settlement due to Extraneous Causes
Chapter # 11: Dams and Dam Foundations

Download the Book

The Content is for Members Only !!!

This Book is available to download for our free members, you can simply click the button below to signup / login for your free membership and download the book now.

In the near future, energy is converted as a luxury item and water is considered as the most vital item in the world due to reduction of water resources in most areas. In this condition, role of water science researchers is more important than ever.

If a water engineering student is not educated well, he/she will not solve problems of water science in the future. Many engineer students learn all necessary lessons in university but they cannot to answer to the problems or to pass the exams because of forgetfulness or lack of enough exercise.

This book contains one hundred essential problems related to water engineering with a small volume (20 problems about irrigation, 20 about drainage, 20 about water quality, 20 about hydrology and a20 about hydraulics).

Undoubtedly, many problems can be added to the book but the author tried to mention only more important problems and to prevent increasing volume of the book due to help of feature of portability of the book. 

Name of the Book 

Handbook of Water Engineering Problems

Author of the Book

Mohammad Valipour

Download the Book

The Content is for Members Only !!!

This Book is available to download for our free members, you can simply click the button below to signup / login for your free membership and download the book now.

Fluid mechanics is encountered in almost every area of our physical lives. Blood flows through our veins and arteries, a ship moves through water and water flows through rivers, airplanes fly in the air and air flows around wind machines, air is compressed in a compressor and steam expands around turbine blades, a dam holds back water, air is heated and cooled in our homes, and computers require air to cool components. 

All engineering disciplines require some expertise in the area of fluid mechanics. 

Fluid Mechanics 

In this book we will present those elements of fluid mechanics that allow us to solve problems involving relatively simple geometrics such as flow through a pipe and a channel and flow around spheres and cylinders. 

But first, we will begin by making calculations in fluids at rest, the subject of fluid statics. 

The math requirement is primarily calculus but some differential equation theory will be used. The more complicated flows that usually are the result of more complicated geometries will not be presented in this book. 

Title of the Book

Fluid Mechanics

Authors of the Book

Merle Potter, Ph.D.
David C. Wiggert, Ph.D.

Contents of the Book

Chapter # 1: Basic Information
Chapter # 2: Fluid Statics
Chapter # 3: Fluids in Motion
Chapter # 4 : The Integrated Equations
Chapter # 5: Differential Equations
Chapter # 6: Dimensional Analysis and Simlitude
Chapter # 7: Internal Flows
Chapter # 8 : External Flows
Chapter # 9 : Compressible Flow
Chapter # 10: Flow in pipes and Pumps
Appendix A Units and Conversions
Appendix B Vector Relationships
Appendix C Fluid Properties

Download the Book

The Content is for Members Only !!!

This Book is available to download for our free members, you can simply click the button below to signup / login for your free membership and download the book now.

Dutch designer Joris Laarman has designed a pedestrian bridge for Amsterdam that will be 3D printed by robots. The ornate metal structure, which will span a canal in the Dutch city, will be printed in-situ by robotic arms. The location of the bridge will be announced soon and completion is set for 2017.The versatile six-axis robots – which are able to rotate their arms along six different planes of movement – will print a load-bearing structure that will support their own weight as they work.

This will allow them to start on one bank of the canal and work their way across to the other side, printing steel as they go.

"This bridge will show how 3D printing finally enters the world of large-scale, functional objects and sustainable materials while allowing unprecedented freedom of form," said Laarman. "The symbolism of the bridge is a beautiful metaphor to connect the technology of the future with the old city, in a way that brings out the best of both worlds."

The project has been developed by MX3D, a technology startup launched by Joris Laarman Lab to investigate ways of printing large, sophisticated structures.

It builds on technology developed by Laarman that allows industrial robots to "draw" metal structures in the air. This potentially allows far larger structures to be printed than are currently possible, and means the technology can start to move out of the factory and onto the construction site.
What distinguishes our technology from traditional 3D printing methods is that we work according to the 'printing outside the box' principle," said Tim Geurtjens, chief technology officer at MX3D.
"By printing with six-axis industrial robots, we are no longer limited to a square box in which everything happens," Geurtjens added. "Printing a functional, life-size bridge is of course the ideal way to showcase the endless possibilities of this technique."

The project, which is supported by design software company Autodesk and construction company Heijmans, could eventually allow entire buildings to be printed.

"The MX3D platform is a potential game changer," said Maurice Conti, director of strategic innovation at Autodesk. "Breaking free of the traditional limitations of additive manufacturing – small-size prints and poor material performance – this technology opens up possibilities for architectural-scale, relatively low-cost, metal structures that are as complex as the designer’s imagination."

Prior to the development of quantitative structural theories in the mid-18th century and since, builders relied on an intuitive and highly developed sense of structural behavior. The advent of modern mathematical modeling and numerical methods has to a large extent replace this skill with a reliance on computer generated solutions to structural problems.

Professor Hardy Cross aptly expressed his concern regarding this in the following quote 

There is sometimes cause to fear that the scientific technique, the proud servant of the engineering arts, is trying to swallow its master. 

What is structural Analysis?

It is inevitable and unavoidable that designers will utilize continually improving computer software for analyses. However, it is essential that the use of such softwares should only be undertaken by those with the appropriate knowledge and understanding of the mathematical modeling, assumptions and limitations inherent in the programs they use.

Students adopt a variety of strategies to develop their knowledge and understanding of structural behavior e.g. the use of :- 
a) Computer to carry out sensitivity analyses
b) Physical models to demonstrate physical effects such as buckling, bending, the development of tension and compression and deformation characteristics. 
c) The study of worked examples and carrying out analysis using “hand” methods. 

This textbook focuses on the provision of numerous fully detailed and comprehensive worked examples for a wide variety of structural problems. In each chapter a resume of the concepts and principles involved in the method being considered is given and illustrated by several examples. A selection of problems is presented which students should undertake on their own prior to studying the given solutions.

Students are strongly encouraged to attempt to visualize/sketch the defected shape of a loaded structure and predict the type of forces in the member prior to carrying out the analysis.

Title of the Book

Examples in structural analysis

Author of the Book

William M.C. McKenzie

Contents of the Book

1. Structural analysis and design
2. Material and section properties
3. Pin-Jointed frames
4. Beams
5. Rigid Jointed Frames
6. Buckling Instability
7. Direct Stiffness Method
8. Plastic Analysis

Download the Book

The Content is for Members Only !!!

This Book is available to download for our free members, you can simply click the button below to signup / login for your free membership and download the book now.

Danish-Icelandic artist Olafur Eliasson has created a bridge spanning a Copenhagen canal, Denmark which features a series of wire masts based on ships' rigging

the Cirkelbroen (Circle Bridge) by Olafur Eliasson spans the Christianshavn Canal to connect the district's Christiansbro neighbourhood and Appleby's Square on either side of the water.

The 40-metre-long footbridge is made from five interconnected circular platforms.

Each of the irregularly sized circles features a tall mast in reference to the boats that sail Copenhagen's waterways. Over 110 tensioned wires are threaded between the base of the bridge and the tips of five poles.

"Fish cutters were often moored in the harbour right next to each other, and sometimes it seemed as if you could actually walk across the harbour by going from boat to boat."
"While I was working on the bridge, I picked up inspiration from this place and it made me think of fishing boats from my childhood on the island," said Eliasson.

The central platform is articulated to allow the bridge to swing back on itself, creating a nine-metre gap for passing boat traffic while smaller boats such as kayaks can pass below the elevated podiums.

Red LEDs set in the balustrades illuminate the structure at night and are synchronised to turn on and off with the area's street lights. Curving Brazilian Guariuba wood handrails are affixed to the top of a crisscrossing arrangement of red railings.

A new pedestrian and cycle bridge connecting Nine Elms on the South Bank with the historic Pimlico embankment is a key component in the Partnership’s transport development plans.

Transport for London (TfL)’s feasibility study has confirmed the bridge is viable and would be a valuable addition to central London’s transport network. The exact location is yet to be confirmed but the preferred options would land close to the site of the new US Embassy.

In December 2014, Wandsworth Council launched an international competition to design a new bridge between Nine Elms and Pimlico. See the dedicated website for full details.

Once a winning design is revealed in autumn 2015 the Partnership will explore a range of funding options which could include sponsorship.

Ravi Govindia, leader of Wandsworth Council and co-chair of the Nine Elms Vauxhall Partnership, said:

“This competition is calling for architects from across the globe to come forward with exceptional, inspiring designs for a new bridge at the centre of the world’s greatest city. The successful entry will have to win the hearts of Londoners who are tremendously proud of their river and its rich architectural heritage.

“There are considerable challenges and engineering feats to overcome. The design must work alongside the cutting edge architecture emerging on the south bank as well as the elegant frontages on the north.  The landing points on both sides must integrate sensitively with their surroundings and provide a smooth and safe experience for the pedestrian and cyclists who use it.

Architects have unveiled ambitious new designs for a cycle-friendly bridge across the Thames in east London.
London's First Pedestrian and Cycle Bridge

The new crossing, deemed “vital” by backers, would link the rapidly expanding Canary Wharf and Isle of Dogs areas north of the river to Rotherhithe on the south bank.

Designers say the project, which would cost almost £90m to complete, would be “unique in the world” and help reinforce London’s status as a tech hub.

The scheme was first conceived by chairman of reForm Architects Nik Randall, who has lived in Southwark for 28 years and had become exasperated at the lack of river crossings serving the area, and Gary Elliott, of engineering firm Elliott Wood.

“It was initially something that was a self-starting idea,” Mr Randall told the Standard.

KOCHI: Cochin International Airport is the first airport in the world which runs completely on solar power. Since August, the airport has used 46,000 solar panels laid across 45 acres to power all its electricity needs, and sell excess power to the government-run grid.

At night, when the sun doesn’t shine, it pulls some of that power back from the grid, making the airport effectively “carbon neutral.” The solar plant will help CIAL to reduce carbon emissions equal to 1.75 lakh MT for the next 25 years. This is equal to planting 30 lakh trees.

 As per BBC report the airport started with a small pilot project by installing a solar energy plant with 400 panels on its rooftop in 2013. When that experiment succeeded, it decided to go all the way. In
August this year, the airport became totally self sufficient in meeting its energy needs after it installed a 12 megawatt solar plant close to the cargo terminal.

 The installation of the solar plant cost nearly $9.5m (£6.27m) and took around six months to complete. The company is hopeful of recouping the costs in less than six years.

The airport will double its capacity from present 13.1 MW as power usage will be doubled as new international terminal will be functional this January. Also Read: Baripatha: First Village In Odisha To Be Powered Entirely By Solar Energy

Saad Iqbal

{picture#} Hi there, I am Saad Iqbal from Pakistan - Founder of Iamcivilengineer. I am Currently Working in a Consultancy Firm as Junior Engineer and am a Passionate blogger and a Civil Engineer from UET Taxila, Pakistan. {facebook#} {twitter#} {google#} {pinterest#} {youtube#}


{picture#} Hi there, I am Saad Iqbal from Pakistan - Founder of Iamcivilengineer. I am Currently Working in a Consultancy Firm as Junior Engineer and am a Passionate blogger and a Civil Engineer from UET Taxila, Pakistan. {facebook#} {twitter#} {google#} {pinterest#} {youtube#}
Powered by Blogger.
- Going for an Interview? Get Prepared today by 300+ Civil Engineering Interview Questions Read Here