Prestressed Concrete - E-Book

Prestressed concrete is a form of concrete used in construction which is "pre-stressed" by being placed under compression prior to supporting any loads beyond its own dead weight. This compression is produced by the tensioning of high-strength "tendons" located within or adjacent to the concrete volume, and is done to improve the performance of the concrete in service. Tendons may consist of single wires, multi-wire strands or threaded bars, and are most commonly made from high-tensile steels, carbon fiber or aramid fiber. The essence of prestressed concrete is that once the initial compression has been applied, the resulting material has the characteristics of high-strength concrete when subject to any subsequent compression forces, and of ductile high-strength steel when subject to tension forces. This can result in improved structural capacity and/or serviceability compared to conventionally reinforced concrete in many situations.

Download Ebooks:

1. Prestressed Concrete Design

2. Prestressed Concrete by Krishna Raju

E-Books Building Materials - Construction

Building materials are those materials which is used for construction purposes. Many naturally occurring substances, such as clay, rocks, sand, and wood, even twigs and leaves, have been used to construct buildings. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The manufacturing of building materials is an established industry in many countries and the use of these materials is typically segmented into specific specialty trades, such as carpentry, insulation, plumbing, and roofing work. They provide the make-up of habitats and structures including homes. Commonly used building materials are : Cement, Sand, Aggregate, Steel, Wood, Tiles, Marble Stone e.t.c.

Building Materials E-Books:

1. Building Material by Duggal

2. Building Material -1 IGNOU

3. Building Material -2 IGNOU

4. Engineering Materials - IGNOU

IRC:SP:84-2014 MANUAL OF SPECIFICATIONS & STANDARDS FOR FOUR LANING OF HIGHWAYS THROUGH PUBLIC PRIVATE PARTNERSHIP

Manual for Specifications & Standards for Four Laning of Highways Through Public Private Partnership (First Revision)

Dounload : IRC SP 84-2014

E-Book : Irrigation and Water Resource Engineering

Water Resource Engineering is a specific kind of civil engineering that involves the design of new systems and equipment that help manage human water resources. Some of the areas Water Resource Engineers touch on are water treatment facilities, underground wells, and natural springs.

View/Download E-books : Water Resource Engineering (IIT Kharagpur) & More books...

BRIDGE ENGINEERING

Definition : A structure built to span and provide passage over a river, chasm, road, or any other physical hurdle. The function required from the bridge and the area where it is constructed decides the design of the bridge.

The first bridges were made by nature — as simple as a log fallen across a stream. The first bridges made by humans were probably spans of wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. Most of these early bridges could not support heavy weights or withstand strong currents. It was these inadequacies which led to the development of better bridges.
The oldest surviving stone bridge in China is the Zhaozhou Bridge, built from 595 to 605 AD during the Sui Dynasty. This bridge is also historically significant as it is the world's oldest open-spandrel stone segmental arch bridge. The first book on bridge engineering was written by Hubert Gautier in 1716. With the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron did not have the tensile strength to support large loads. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel.
Bridges are classified on the basis that how the four forces namely shear, compression, tension, and moment are distributed in the bridge structure.

Download Bridge Engineering e-Books

Introduction to Bridge Engineering

Bridge Engineering - Hand Book

Structural analysis and design of concrete bridges

Bridge Engineering - Major Bridges

Bridge Engineering - Wabash Bridge competition

Civil Engineering Laboratory Manual -E-books

Study material of  Civil Engineering Laboratory Manual (pdf)

Laboratory Manual - Concrete Technology

Laboratory Manual - Fluid Mechanics -I 

Laboratory Manual -  Fluid Mechanics -II

Laboratory Manual - Soil Mechanics

Laboratory Manual - Surveying -I 

Laboratory Manual - Surveying -II 

Transportation Engineering (E-Books)

Introduction to transportation engineering

Overview

Moving/Mobility is a basic human need. From the times immemorial, everyone travels either for food or leisure. A closely associated need is the transport of raw materials to a manufacturing unit or finished goods for consumption. Transportation fulfills these basic needs of humanity. Transportation plays a major role in the development of the human civilization. For instance, one could easily observe the strong correlation between the evolution of human settlement and the proximity of transport facilities. Also, there is a strong correlation between the quality of transport facilities and standard of living, because of which society places a great expectation from transportation facilities. In other words, the solution to transportation problems must be analytically based, economically sound, socially credible, environmentally sensitive, practically acceptable and sustainable. Alternatively, the transportation solution should be safe, rapid, comfortable, convenient, economical, and eco-friendly for both men and material.

E-Books for Transportation Engineering :

Transportation Engineering

Railway Engineering 

Airports Fifth Edition-2010

BUILDING ORIENTATION IN WARM AND DRY CLIMATE

Orientation of building should be done for the climatic zone in which the building is situated. The purpose of orientation is to provide residents a comfortable living space throughout the year even under severe undesirable weather conditions. Here we will discuss about orientation of building for maximum comfort under hot and dry climatic conditions.

Hot and dry climatic zones: Hot and dry climatic zones generally occur at This climatic condition generally occurs at latitude between 15 degrees to 30 degrees on both the hemispheres. Maximum day time summer temperature goes as high as 45 degree centigrade and relative humidity as low up to 20 %. This type of climate is experienced in areas far from sea coasts and do not receive heavy rainfall. Thus, the humidity is very low. So, the buildings in this climatic zone should be orientated based on solar point of view so that the building receives maximum solar radiation during winter season and minimum radiation during summer season.

Desirable features of buildings in hot and dry climatic zones are:

1. Orientation of building: Orientation of building in this climatic zone should be such that non-habitat rooms can be located on outer faces to act as thermal barrier. Longer walls of building should face North & South so that the building gets minimum solar exposure. Preferably the kitchen should be located on leeward side of the building to avoid circulation of hot air and smell from the kitchen.

2. Windows and Openings in Walls: Windows and large openings in walls with heavy shutters should be provided on northern and western faces as light coming from north is always diffused and indirect. Also direction of breeze, which is from west at most of the places, enters from opening on west side. Windows area should be 15 to 20 percent of floor area. Internal courtyard caters for cross ventilation & thermal buffer. Suitable radiation barriers in the form of canopies, Chhajjas, long verandahs etc. should be provided on the West side of the building. Sufficient number of ventilators close to the bottom of slab should be provided for hot air to escape the room.

3. Orientation of Walls: Thickness of wall plays an important role in heat insulation of building. Thicker outer walls are preferred as it behaves as an insulating barrier. Painting of walls from outside also plays an important role. Walls with light and shining paints on outer surface have good reflective quality and do not absorb heat. The surface of walls should be smooth and non-dust catching type.

Walls constructed with hollow blocks / bricks and Cavity Walls can also be provided as they provide very good thermal insulation.

4. Insulation of Roofs: Roofs should be built up with good insulating material having slope in windward direction and which reflects the radiation and does not absorb heat. False ceiling can be used to improve thermal performance of building. Terracing should be provided on the flat roof with mud phuska, lime concrete, foamed concrete or burnt clay block paving over roof slab. Top roof surface should be made reflective by providing whitewashing or any reflective paint.

5. Growing of Vegetation: Large shady trees whose roots do not strain foundation and basement should be planted near external walls to provide shade.

6. Special Building Orientation Requirements: Outdoor sleeping area for summer nights preferably is provided. Desert coolers and fans can be used during summer months. Therefore, proper space to provide coolers should be planned in the building.

GUIDLINES FOR CIVIL SITE ENGINEERS

Following are few general points to remember for civil site engineers to make the construction work easier while maintaining quality of construction:

• Lapping is not allowed for the bars having diameters more than 36 mm.
• Chair spacing maximum spacing is 1.00 m (or) 1 No per 1m2.
• For dowels rod minimum of 12 mm diameter should be used.
• Chairs minimum of 12 mm diameter bars to be used.
• Longitudinal reinforcement not less than 0.8% and more than 6% of gross C/S.
• Minimum bars for square column is 4 No’s and 6 No’s for circular column.
• Main bars in the slabs shall not be less than 8 mm (HYSD) or 10 mm (Plain bars) and the distributors not less than 8 mm and not more than 1/8 of slab thickness.
• Minimum thickness of slab is 125 mm.
• Dimension tolerance for cubes + 2 mm.
• Free fall of concrete is allowed maximum to 1.50m.
• Lap slices not be used for bar larger than 36 mm.
• Water absorption of bricks should not be more than 15 %.
• PH value of the water should not be less than 6.
• Compressive strength of Bricks is 3.5 N / mm2.
• In steel reinforcement binding wire required is 8 kg per MT.
• In soil filling as per IS code, 3 samples should be taken for core cutting test for every 100m2.

Density of Materials:

Material	Density
Bricks	1600 – 1920 kg/m3
Concrete block	1920 kg/ m3
Reinforced concrete	2310 – 2700 kg/ m3

Curing time of RCC Members for different types of cement:

Super Sulphate cement: 7 days

Ordinary Portland cement OPC: 10 days

Minerals & Admixture added cement: 14 days

De-Shuttering time of different RCC Members

RCC Member	De-shuttering time
For columns, walls, vertical form works	16-24 hrs.
Soffit formwork to slabs	3 days (props to be refixed after removal)
Soffit to beams props	7 days (props to refixed after removal)
Beams spanning upto 4.5m	7 days
Beams spanning over 4.5m	14 days
Arches spanning up to 6m	14 days
Arches spanning over 6m	21 days

Cube samples required for different quantity of concrete:

Quantity of Concrete	No. of cubes required
1 – 5 m3	1 No’s
6 - 15 m3	2 No’s
16 – 30 m3	3 No’s
31 – 50 m3	4 No’s
Above 50 m3	4 + 1 No’s of addition of each 50 m3

STAIRS TYPES AND THEIR USES

Types of stairs is broadly based on the shape of the stairs. Straight stairs, Turning stairs and Continuous stairs are broad types of stairs.

A stair is a set of steps leading from one floor of a building to another, typically inside the building. The room or enclosure of the building, in which the stair is located is known as staircase. The opening or space occupied by the stair is known as a stairway.

Types of Stairs – Classification of stairs:

Stairs can be broadly classified into three types:

1. Straight stairs

2. Turning stairs

3. Continuous stairs

1. Straight stairs:

Generally for small houses, available width is very retractable. So, this type of straight stairs are used in such conditions which runs straight between two floors. This stair may consists of either one single flight or more than one flight with a landing.

2. Turning stairs:

Turning stairs are sub classified as:

a) Quarter turn stairs

b) Half turn stairs ( dog legged stairs)

c) Three – quarter turn stairs

d) Bifurcated stairs

a) Quarter turn stairs:

A quarter turn stair is the one which changes its direction either to the right or to the left but where the turn being affected either by introducing a quarter space landing or by providing winders. In these type of stairs the flight of stair turns 90 degrees art landing as it rises to connect two different levels. So it is also called as L-stair. Again these quarter turn stairs are two types.

i. Newel quarter turn stairs:

These type of stairs have clearly visible newel posts at the beginning of flight as well as at the end. At the quarter turn, there may either be quarter space landing or there may be winders.

ii. Geometrical quarter turn stairs:

In geometrical stairs, the stringer as well as the hand rail is continuous without any newel post at the landing area.

b) Half turn stairs:

In case of half turn stairs its direction reversed, or changed for 180^o. Such stairs are quite common. Again these are three types.

i. Dog-legged stairs

Because of its appearance in sectional elevation this name is given. It comes under the category of newel stairs in which newel posts are provided at the beginning and end of each flight.

ii. Open newel half turn stair

In this type of open newel half turn stairs, stair has a space or well between the outer strings. This is the only aspect in which it differs from the doglegged stair.

iii. Geometrical half turn stairs

In case of geometrical half turn stairs the stringers and the hand rails are continuous, without any intervening newel post. These stairs may contains either with half space landing or without landing.

c) Three quarter turn stairs:

The direction of stairs changed three times with its upper flight crossing the bottom one in the case of three quarter turn stairs. These stairs are may either be newel or open newel type. This type stairs are generally used when the vertical distance between two floors is more and as well as length of the stair room is limited.

d) Bifurcated stairs:

Bifurcated stairs are commonly used in public building at their entrance hall. This has a wider flight at the bottom, which bifurcates into two narrower flights, one turning to the left and other to the right, at landing.it may be either of newel type with a newel post or of geometrical type with continuous stringer and hand rails.

3. Continuous stairs:

This type of stairs neither have any landing nor any intermediate newel post. They are geometric in shape. These are may be of following types.

• Circular stairs
• Spiral stairs
• Helical stairs

Circular stairs or spiral stairs are usually made either of R.C.C or metal, and is placed at a location where there are space limitations. Sometimes these are also used as emergency stairs, and are provided at the back side of a building. These are not comfortable because of all the steps are winders and provides discomfort.

 A helical stair looks very fine but its structural design and construction is very complicated. It is made of R.C.C in which a large portion of steel is required to resist bending, shear and torsion.