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Structures In Practice By Gautam H. Oza

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By Gautam H. Oza

1st Edition 2018
ISBN : 9789385039348
Binding : Paperback
Pages : 626 + 20 = 646
Size (mm) : 279 × 30 × 203
Weight : 1300 g

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Description

This book is an outcome of extensive experience of the author in a design office as a consulting professional engineer.

The book deals with elements or systems which are significant parts of the “structure” as a whole and some stand-alone structures. Some cogent information or case studies related to the chapter are given as Annexes to the respective chapter.

Also included are several Design Aids and Appendices which the author found immensely useful; hopefully, the design engineer will be at an advantage with these handily available. Whereas most of the discussion in the book is related to RC (Reinforced Concrete) structures, some common and predominantly steel structures have been included viz. portal frames, Vierendeel girders, chimneys and parking structures.

For easy reading, the book is divided into self-contained chapters dealing with each topic. It contains useful tables of data and is profusely illustrated with diagrams and photographs to assist the reader. Fundamental concepts are lucidly presented and derived and empirical formulae given with clarity of underlying assumptions.

Some case histories have been included. One is design of a large span (84.0 m) portal frame. It gives the exact procedure that was followed while designing a large span portal frame, when posed with a peculiar problem during the professional practice. The aim in presenting this “case” is to acquaint the readers to almost all the aspects of such a structure, with emphasis not only on the design but also on execution. Almost all the salient parameters related to the design and execution are included. The second “case” is of another peculiar problem; making an opening for an additional flue duct in an existing 100 m high RC chimney. The salient information for planning and devising the scheme for execution is given. For both these cases, detailed drawings and the specific instruction sheets prepared for proper and fault free execution are included. These are meant for the students with inquisitive minds and the practicing engineers seeking guidance when faced with not so usual problems.

Some worked examples have been given in the book; these are given at the ends of the respective chapters. These should help the engineer in dealing with the problems during practice.

The book comprehensively covers the subject for degree courses (graduate and post-graduate) in engineering of all the Indian Universities and examinations of professional bodies. Written in a simple language, with illustrative references, it will be useful to students to grasp the subject and to the practicing engineers in designing of the structures.

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Valuation of Real Properties By Rangwala

978-93-85039-34-8

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1 : CORBELS – BRACKETS AND SHEAR CONNECTORS
2 : GRID SYSTEMS
3 : PORTAL FRAMES
ANNEX A3 : SHED FOR STORAGE OF LIGNITE – A
CASE STUDY
4 : VIERENDEEL FRAMES
5 : STAIRS AND RAMPS
6 : FOOTINGS – FOUNDATIONS
7 : RETAINING WALLS
8 : TIEBACKS AND ANCHORS
9 : SHEAR WALLS – AN INTRODUCTION
10 : CULVERTS
11 : UNDERGROUND WATER TANKS
(ALSO WATER TREATMENT & SEWAGE TREATMENT
PLANT STRUCTURES AND R.C. PIPES)
12 : OVERHEAD WATER TANKS
ANNEX A12 : PROPERTIES OF SHELLS OF REVOLUTION
13 : SWIMMING POOLS
ANNEX A13 : HYGIENE, SANITATION AND FILTRATION
IN SWIMMING POOLS
14 : SILOS, BUNKERS AND HOPPERS
15 : PARKING SHED STRUCTURES
16 : CHIMNEYS
ANNEX A16 : 4TH OPENING FOR FLUE IN EXISTING RCC
CHIMNEY
17 : MACHINE FOUNDATIONS
18 : PRESTRESSED CONCRETE – AN INTRODUCTION
19 : DELETERIOUS EFFECTS ON CONCRETE
ANNEX A19-1 : CONCRETE FOR HIGH TEMPERATURES
ANNEX A19-2 : DETERIORATION OF CONCRETE
(IN A SWITCHYARD) – A CASE STUDY
DESIGN AIDS
APPENDICES
REFERENCES
INDEX

Details Content

Chapter 1 CORBELS – BRACKETS AND SHEAR CONNECTORS

1-1 General
1-2 Brackets or Corbels
1-2-1 Flexure
1-2-2 Bearing
1-2-3 Diagonal Tension
1-2-4 Splitting
1-2-5 Horizontal Movement
1-3 Detailing of Corbel
1-4 Shear Friction
1-5 American Method of Design
1-6 Anchorage of Tensile Reinforcement
1-7 Shear Connectors
1-8 Example 1-1

Chapter 2 GRID SYSTEMS

2-1 General
2-2 Types of Grids
2-3 Load Distribution in Grid Beams
2-3-1 Grid – Three × Three Panels
2-3-2 Grid – Five × Five Panels
2-4 Rankine-Grashoff Approximate Analysis Method
2-5 Plate Theory Analysis Method
2-6 Flexibility and Stiffness Methods
2-6-1 Flexibility Method
2-6-2 Stiffness Method
2-7 Stiffness Method of Structural Analysis
2-8 Finite Element Method (FEM)
2-9 Conclusion
2-10 Example 2-1

Chapter 3 PORTAL FRAMES

3-1 Introduction
3-2 Portal Frames
3-2-1 Behaviour
3-2-2 Types / Forms of Portal Frames
3-2-3 Design Considerations
3-2-4 Why Select Portal Frame as the Form of Structure?
3-3 Approximate Analysis for Lateral Loads
3-4 Hinges – RC Portal Frames
3-5 Portal Frames in Steel
3-5-1 Analysis of Steel Portal Frames
3-5-2 Rigid Frame Knees (or Haunches)
3-5-3 Summary
3-5-4 Advantages and Disadvantages of Open-Web Portal Frames
3-6 A Case Study
3-7 Photographs
3-8 Examples
3-8-1 Example 3-1
3-8-2 Example 3-2
Annex A3 SHED FOR STORAGE OF LIGNITE – A CASE STUDY
A3-1 General
A3-2 Stockpile Capacities
A3-3 Need for Covering Stockpiles
A3-4 Dimensions, Analysis and Design
A3-4-1Dimensions
A3-4-2Geometry – Inner Dimensions
A3-4-3Design Loads
A3-4-4Analysis
A3-4-5Design
A3-4-6Foundations
A3-4-7Structural Steel Quantities
A3-5 Erection of Portal Frames
A3-6 Additional Features
A3-7 Figures

Chapter 4 VIERENDEEL FRAME / TRUSS / GIRDER

4-1 Introduction
4-2 Choice of Trusses or Rolled Sections
4-2-1 Use of Trusses in Buildings
4-2-2 Types of Trusses
4-2-2-1Fink Truss
4-2-2-2Howe Truss
4-2-2-3Pratt Truss
4-2-2-4Warren Truss
4-2-2-5North Light Truss / Saw-Tooth Truss
4-3 Vierendeel Trusses or Frames
4-4 Analysis
4-5 Connections
4-6 Why a Vierendeel?
4-7 Cases of Vierendeel Application by Author
4-7-1 Photograph 4-1
4-7-2 Photograph 4-2
4-7-3 Photograph 4-3
4-8 Example 4-1

Chapter 5 STAIRS AND RAMPS

5-1 General
5-2 Forms of Stairs
5-2-1 Stair Spanning along the Flight – with Waist Slab
5-2-2 Stair Spanning along the Flight – with Beams at Ends of Flights
5-2-3 Stair with One Stringer Beam
5-2-4 Stair with Two Stringer Beams
5-2-5 Stair with Three Flights and Open Stair Well
5-2-6 Stand Alone Stairs
5-2-7 Stair on RC Pin
5-2-8 Spiral Stair
5-2-9 Trussed Stair
5-2-10 Slabless Tread-Riser Stair
5-2-10-1Stiffness and Carry-over Factors
5-2-11 Helical Stairs
5-3 Ramp for Wheelchair Access
5-4 Cases of Stairs and Ramp by Author
5-4-1 Photograph 5-1
5-4-2 Photograph 5-2
5-4-3 Photograph 5-3
5-4-4 Photographs 5-4 and 5-5
5-5 Example 5-1

Chapter 6 FOOTINGS – FOUNDATIONS

6-1 Foundations
6-1-1 Distribution of Pressure
6-1-2 Bearing Capacity
6-1-3 Settlement
6-1-4 Uplift
6-1-5 Foundation Types
6-1-6 Piers and Caissons
6-2 Footings
6-2-1 Individual Footings
6-2-2 Bearing Capacity – Bearing Pressures and Settlement
6-2-3 Strip Footings
6-2-4 Isolated Spread Footings
6-2-5 Combined Footings
6-2-6 Split Footings
6-3 Raft Foundations
6-3-1 Types of Rafts
6-3-2 Stability and Settlement of Raft Foundations
6-3-3 Design of Rafts
6-3-3-1Rigid Method
6-3-3-2Elastic Plate Method
6-3-3-3Finite Difference Method
6-3-3-4Finite Element Method
6-3-3-5General
6-4 Example 6-1

Chapter 7 RETAINING WALLS

7-1 Introduction
7-2 Forces Acting on Earth Retaining Wall
7-3 Stability Considerations
7-4 Earth Pressures
7-4-1 Earth Pressure Equations of Common Use
7-4-2 Earth Pressure Coefficients
7-4-3 Cohesive Soils
7-4-4 Passive Earth Pressures
7-5 Drainage and Weep Holes
7-6 Hydraulic Pressure
7-7 Selection of Type of the Wall
7-8 Gravity Walls
7-9 Reinforced Concrete Walls
7-9-1 Types of Reinforced Concrete Walls
7-9-2 Pressure on Reinforced Concrete Walls
7-9-3 Stability of Retaining Walls
7-9-4 Base Width
7-9-5 T-Shaped Retaining Walls
7-9-6 Counterfort Type Retaining Walls
7-9-7 Anchored Retaining Walls
7-9-8 Anchorages (or Deadman)
7-10 Example 7-1

Chapter 8 TIEBACKS AND ANCHORS

8-1 Introduction
8-2 Tiebacks
8-3 Anchors with Normal Pressure Grouts
8-4 High Pressure Grouts
8-5 Anchors with High Pressure Grouts
8-5-1 Load Capacity of Anchors
8-6 Tendons
8-6-1 Factor of Safety
8-6-2 Testing
8-7 Creep and Cyclic Loading
8-8 Corrosion Protection
8-9 Uplift

Chapter 9 SHEAR WALLS – AN INTRODUCTION

9-1 General
9-1-1 Advent of High Rise Buildings
9-1-2 High Strength Materials
9-1-3 New Design Concepts
9-1-4 New Structural Systems
9-1-5 Improved Construction Methods
9-2 Wind – Earthquakes – Serviceability
9-2-1 Wind Forces
9-2-2 Earthquake Effects
9-2-3 Wind and Earthquake
9-2-4 Serviceability Criteria
9-3 Buildings with Shear Walls
9-4 Coupled Shear Wall Structures
9-5 Frame – Shear Wall Structures
9-6 Analysis – Continuum Approach
9-7 Analysis for Lateral Loads
9-8 Proportioning of Shear Walls
9-9 Applications

Chapter 10 CULVERTS

10-1 General
10-2 Loading
10-3 Culverts with Slab-Beam Deck
10-4 Effective Width Method
10-5 Slabs Supported on Four Edges – Pigeaud’s Coefficients
10-6 Westergaard’s Method
10-7 Shear Force
10-8 Load Distribution in Beams

10-9 Method of Distribution Coefficients
10-9-1 Longitudinal Moments
10-9-2 Transverse Moments
10-10 Box Culvert
10-10-1 Loads on Box Culvert
10-11 Example 10-1

Chapter 11 UNDERGROUND WATER TANKS (ALSO WATER
TREATMENT & WASTE WATER TREATMENT
PLANT STRUCTURES AND RC PIPES)

11-1 General
11-2 Water Tightness
11-3 Concrete Quality and Curing
11-4 Joint Details and Placement
11-4-1 Construction Joint
11-4-2 Contraction Joint
11-4-3 Expansion Joint
11-4-4 Reinforcing for Shrinkage
11-5 Design Parameters / Design Considerations
11-5-1 Loads
11-5-2 Foundations
11-5-3 Structural Design Parameters
11-6 Design of Circular Tanks
11-6-1 Edge Conditions
11-6-2 Side Walls – Shrinkage and Tension
11-7 Design of Rectangular Tanks
11-7-1 Loads and Analysis of Walls
11-7-2 Loadings and Analysis of Floors and Roofs
11-7-3 Foundations
11-8 Some Underground Water Tanks – Constructed / Actual
11-9 Large Water Reservoirs
11-10 Water Treatment Plant and Waste Water Treatment Plant
11-10-1 Water Treatment Plant
11-10-2 Waste Water Treatment Plant
11-11 Appurtenant Structures
11-11-1 Control Structures
11-11-2 Pumping Stations
11-11-3 Vibrations
11-11-4 Corrosion Protection
11-11-4-1Chlorination
11-11-4-2Coatings
11-12 Reinforced Concrete (R.C.) Pipes
11-12-1 Stresses in Pipe – Own Weight
11-12-2 Stresses in Pipe – Water Inside
11-12-3 Stresses in Pipe – Earth Fill over Haunches
11-12-4 Stresses in Pipe – Uniformly Distributed Load on Top
11-12-5 Stresses in Pipe – Uniform Pressure from Sides
11-12-6 Stresses in Pipe – Varying Pressure from Sides
11-12-7 Stresses in Pipe – Point Load at Crown
11-12-8 Pipes Supported on Quarter Circumference
11-12-9 Stresses in Pipes – Summary
11-12-10 Reinforcement and Pipe Thickness
11-13 Examples
11-13-1 Example 11-1
11-13-2 Example 11-2

Chapter 12 OVERHEAD WATER TANKS

12-1 General
12-2 Components in Overhead Tanks
12-2-1 Container
12-2-2 Supporting Systems
12-2-3 Foundations
12-3 Container
12-4 Circular Tanks
12-4-1 Case 1 – Tank Open at Top and Monolithic / Rigid at Base
12-4-2 Case 2 – Tank Wall Monolithic with Base and Roof

12-4-3 Case 3 – Tank Wall Monolithic with Domical or Conical
Base and Roof
12-4-4 Reissener’s Approximate Method
12-4-5 Flat Bottoms of Circular Tanks
12-5 Behaviour of Container Elements
12-5-1 Membrane Analysis
12-5-1-1 Top Dome
12-5-1-2 Ring Beam AA
12-5-1-3 Tank Wall
12-5-1-4 Ring Beam CC and Conical Shell
12-5-1-5 Bottom Dome and Ring Beam BB
12-5-2 Secondary Analysis
12-5-3 Summary
12-5-4 Author’s Observations
12-6 Rectangular Tanks
12-6-1 Walls
12-6-2 Bottom Slab and Roof
12-7 Supporting Systems for Tanks – Columns
12-7-1 Loads on Columns
12-7-2 Bending Moments in Columns
12-7-3 Axial Forces due to Wind
12-8 Supporting System for Tanks – Columns with Bracings
12-8-1 Analysis of Bracings
12-9 Supporting System for Tanks – Shaft
12-10 Foundations
12-11 Some Overhead Water Tanks – Constructed / Actual
12-12 Architectural Drawings
12-13 Overhead Water Tanks – Some Possible Designs
12-14 Example 12-1
12-14-1 Container Conical Bottom
12-14-1-1Hoop Tension
12-14-1-2Container Bottom – Compression
12-14-2 Ring Beam at Bottom of the Conical Bottom
12-14-3 Calculation of Wind Loads and Estimation of Vertical Loads
12-14-3-1Wind Loads
12-14-3-2Vertical Loads
12-14-4 Calculation of Loads due to Earthquake
12-14-5 Supporting Shaft
12-14-5-1Section Properties of Shaft
12-14-5-2Checking Stresses in the Shaft
12-14-6 Foundation Raft
12-14-6-1Determining the Size
12-14-6-2Raft Analysis

Annex A12 PROPERTIES OF SHELLS OF REVOLUTION

A12-1 General
A12-2 Cylindrical Shell
A12-3 Conical Shell
A12-4 Spherical Dome

Chapter 13 SWIMMING POOLS

13-1 General
13-2 Appurtenant / Ancillary Facilities
13-2-1 Lockers
13-2-2 Showers
13-2-3 Strainers – Skimmers
13-2-4 Automated Pool Cleaners
13-2-5 Water Pumps
13-2-6 Safety Features
13-3 Dimensions
13-4 Other Features
13-5 Walls and Floors
13-6 Diving Platforms
13-7 Architectural and Structural Drawings
13-8 Examples
13-8-1 Example 13-1
13-8-2 Example 13-2

Annex A13 HYGIENE, SANITATION AND FILTRATION IN
SWIMMING POOLS

A13-1 Hygiene – Contaminants and Disease
A13-1-1 Sanitation Methods
A13-1-2 Prevention of Diseases in Swimming Pools
A13-1-3 Disinfection Methods
A13-1-3-1Chlorine and Bromine Methods
A13-1-3-2Copper Ion System
A13-1-3-3 Other Systems
A13-2 Filtration Units / Media
A13-2-1 Sand
A13-2-2 Diatomaceous Earth
A13-2-3 Cartridge Filters
A13-3 Water Pumps and Consecutive Dilution

Chapter 14 SILOS, BUNKERS AND HOPPERS

14-1 Bins – Silos and Bunkers
14-2 Design Parameters – Material Properties
14-3 Loadings
14-3-1 Bin Loads – IS:4995
14-4 Airy’s Theory
14-4-1 Shallow Bins or Bunkers
14-4-2 Deep Bins or Silos
14-5 Janssen’s Theory
14-6 Sloping Bottom – Cylindrical Silos
14-6-1 Ring Beam
14-6-2 Secondary Stresses
14-7 Rectangular Bunkers
14-7-1 Rectangular Bunkers with High Side Walls
14-7-2 Battery of Bunkers with High Side Walls
14-7-3 Battery of Bunkers with Low Side Walls
14-7-4 Rectangular Bunkers with Sloping Bottom
14-8 Discussion – Maximum Pressures, Flow and Safety
14-8-1 Maximum Pressures in Silos
14-8-1-1 Pressure Reducing Devices
14-8-2 Modes of Flow in Bins and Silos of Symmetrical Geometry
14-8-3 Safety
14-9 Minimum Thickness of Bin Walls
14-10 Large Storage in Bulk
14-11 Pyramidal Hopper Bottoms
14-11-1 Pressure Normal to Slab / Plate
14-11-2 Bending Moments and Direct Forces
14-11-3 Horizontal Reinforcement
14-11-4 Transverse Reinforcement
14-11-5 Vertical Reinforcement
14-12 Examples
14-12-1 Example 14
14-12-2 Example 14

Chapter 15 PARKING SHED STRUCTURES

15-1 General
15-2 Parking Sheds
15-2-1 Space Requirement
15-3 Some Parking Sheds – Constructed / Actual
15-4 Parking Sheds – Some Possible Designs
15-5 Parking Structures
15-5-1 Structural Aspects
15-5-2 Automated and Automatic Parking
15-5-3 Modular Car Parking
15-6 Example 15

Chapter 16 CHIMNEYS

16-1 General
16-2 Proportioning
16-2-1 Height
16-2-2 Diameter
16-2-3 Thickness
16-3 Chimney Lining / Liners

16-4 Design Factors
16-5 Wind Loading
16-5-1 Radial Pressure
16-5-2 Lateral Swaying and Ovalling
16-5-2-1 Lateral Swaying
16-5-2-2 Ovalling of Circular Section
16-6 Earthquake Loading
16-6-1 Period
16-6-2 Base Shear
16-6-3 Shear Distribution
16-6-4 Earthquake Bending Moments
16-7 Temperature
16-8 Stresses in Chimney Shell
16-8-1 Due to Self-Weight and Wind
16-8-2 Due to Temperature
16-8-3 Effect of only Temperature
16-8-3-1 Effect of Temperature in Compression Zone
16-8-3-2 Effect of Temperature in Tension Zone
16-8-4 Horizontal Stresses
16-9 Opening in Chimney Shell
16-10 Foundations
16-11 Appurtenant Features
16-12 Steel Chimneys
16-13 Case Study
16-14 Example 16

Annex A16 4TH OPENING FOR FLUE IN EXISTING R.C.C.
CHIMNEY

A16-1 The Scheme
A16-2 Study and Decision
A16-3 Execution Aids
A16-3-1 List of Activities
A16-3-2 Notes for Cutting and Removing Concrete Block (from
Existing RCC Chimney)
A16-3-3 Sequence of Activities for Civil Works
A16-4 Execution
A16-5 Drawings and Photographs

Chapter 17 MACHINE FOUNDATIONS

17-1 Introduction
17-2 Types of Machine Foundations
17-3 General requirements of Machine Foundations
17-3-1 Dimensional Criteria
17-3-2 Permissible Amplitudes
17-3-3 Resonance
17-4 Design Parameters
17-4-1 Geometric Properties of Machine Foundations1
17-5 Physical Properties of Elastic Base – Soil below Foundation
17-6 Expression for Spring Stiffness of Elastic Supports
17-6-1 Soils and Elastic Pads
17-6-2 Steel Springs Couzens’ Table for Weight of Foundations
17-8 Foundations for Impact Type Machines
17-8-1 Types of Foundations
17-8-2 Impact Factor
17-8-3 Fatigue Coefficient
17-8-4 Weights of Anvil and Foundation Block
17-8-5 Foundation as Two-Mass-Vibrator System
17-8-6 Thickness of Foundation Block
17-9 Block Type Machine Foundations
17-10 Single-Mass Spring System
17-10-1 Definitions and Symbols
17-10-2 Equation for Forced Vibrations
17-10-3 Effect of Soil Mass
17-11 Semi-Empirical Design of a Block Foundation as a SingleMass Spring System
17-12 Foundations for Reciprocating Machines
17-13 Foundations for Heavy Rotary Machines

17-14 Frequencies and Permissible Amplitudes (For Reciprocating
and Rotary Machines)
17-15 Foundations for High Speed Rotary Machines
17-15-1 Dynamic Analysis
17-15-2 Resonance, Amplitude and Combined Methods
17-16 Other Machines
17-16-1 Machine Tools
17-16-2 Fans and Blowers
17-16-3 Testing Machine with Pulsator
17-16-4 Looms
17-17 Constructional Aspects / Construction Considerations
17-18 Vibration Isolation
17-18-1 Methods of Isolation
17-18-2 Properties of Isolating Materials
17-18-3 Methods of Laying Spring Absorbers
17-18-4 Vibration Isolators or Anti
Vibration Mountings

Chapter 18 PRESTRESSED CONCRETE – AN INTRODUCTION

18-1 Introduction
18-2 Basic / General Principles
18-2-1 Classification and Types of Prestressed Concrete Structures
18-2-2 Stages of Loadings
18-3 Pre-Tensioning
18-3-1 Sequence of Operations – Pre-Tensioning
18-3-2 Appurtenances – Pre-Tensioning
18-4 Post-Tensioning
18-4-1 Sequence of Operations – Post-Tensioning
18-4-2 Appurtenances – Post-Tensioning
18-5 Pre-Tensioning and Post-Tensioning
18-5-1 Systems of Prestressing
18-5-1-1 Freyssinet System
18-5-1-2 Magnel Blaton System
18-5-1-3 Gifford Udall System
18-5-1-4 Lee McCall System
18-5-1-5 Popular Systems of Prestressing
18-5-1-6 Other Methods of Prestressing
18-5-2 Shapes of Concrete Sections
18-5-3 Merits and Demerits of Pre-Tensioning and Post-Tensioning
18-6 High Strength Materials for Prestressed Concrete
18-7 Bond of Prestressing Tendons
18-7-1 Transfer Bond Stress
18-7-2 Flexural Bond Stress
18-8 Losses in Prestress
18-8-1 Losses due to Friction
18-8-2 Anchorage Loss (or Loss due to Slip at Anchorage)
18-8-3 Loss due to Elastic Shortening of Concrete
18-8-4 Loss due to Creep of Concrete
18-8-5 Loss due to Shrinkage of Concrete
18-8-6 Loss due to Relaxation of Steel
18-8-7 Loss due to Creep in Steel
18-8-8 Total Losses of Prestress
18-9 Special Features / Problems
18-9-1 Fire Resistance
18-9-1-1 Conductivity
18-9-1-2 Strength
18-9-1-3 Sensitivity of High Tensile Steel
18-9-1-4 Low Temperature Effect
18-9-2 Fatigue Strength
18-9-3 Impact Resistance
18-9-4 Corrosion Resistance
18-10 Comparison – Prestressed Concrete and Reinforced Concrete

Chapter 19 DELETERIOUS EFFECTS ON CONCRETE

19-1 General
19-2 Exposure to Soft Water
19-3 Exposure to Sulphates

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