ANALYSIS AND DESIGN OF A STRUCTURE

ANALYSIS AND DESIGN In a broad sense, the analysis and design of a structure consists of two parts: The first part deals with the determination of forces at any point or member of the given structure. The second part deals with the selection analysis and design of a structure suitable sections to resist these forces so that the stresses and defor­mations developed in the structure due to these forces are within permis­sible limits. The first part can be termed as "structural analysis" and the second part as "proportioning" or "dimensioning" of members . Before we can start the analysis, we shall require the entire details of the structure, loading and sectional properties. To proportion a structure, we must first know how it will behave under loading. Therefore, the process of analysis and design of a structure forms an integral part of any design.  In practice, the properties of mem­bers are…

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Forms of structure(beam,trusses arch and frames) in structure analysis

FORMS OF STRUCTURES Any civil engineering structure is conceived keeping in mind its intended use, the materials available, cost and aesthetic considerations. The struc­tural analyst encounters a great variety of structures and these are briefly reviewed here. One of the simplest structures is a, simply supported beam, supported on a pin at one end' and a roller at the other (Fig. 1.1a). Such a beam, it may be recalled from the fundamentals of strength of materials, is quite stable and statically determinate and transmits the external loads to the supports mainly through shear and moment. The other types of beams which are more complicated from the point of view of analysis are those with fixed ends and those that are continuous over supports (Figs. 1.1 b and c). As we shall see later, such beams are statically indeterminate and cannot be solved using equations of static equilibrium alone. For longer…

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SI Units for Structural Engineers

SI Units for Structural Engineers The international system of units SI (System Internationale units) Units for Structural Engineers, com­monly called SI, is being adopted allover the world as a uniform meas­urement system. While the complete transition from customary units to the SI system may take years, the use of SI (System Internationale units) Units for Structural Engineers units in the fields of en­gineering and science is proceeding rather rapidly, and it will soon be­ come necessary for the modern civil engineer to gain experience in using the SI system. Fortunately, the cl1~ngeover from the now common MKS units to SI units is quite simple, unlike the changeover from FPS to MKS units. In this book, SI units have been used throughout, with only mi.nor modifications, to suit the requirements of the engineering world. The basic and derived units for various categories of measurement are discussed in the following sections.  TYPICAL BASIC…

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Advantages and disadvantages of Reinforced cement concrete (R.C.C)

In this article : Learn Plain cement concrete, Reinforced cement concrete, Composite action of steel and concrete, Uses of Reinforced concrete, Advantages of R.C.C. ,Disdvantages of R.C.C. Plain Cement Concrete Plain Cement Concrete is a hardened mass obtained from a mixture of cement, sand, gravel and water in definite proportions. These ingredients are mixed together to form a plastic mass which is poured into desired shape moulds called as forms. This plastic mass hardens on setting and we get plain cement concrete. The hardening of this mixture is caused by a chemical reaction between cement and water. Plain cement concrete has good compressive strength but very little tensile strength, thus limiting its use in construction. Plain concrete is used where good compressive strength and weight are the main requirements and tensile stress are very low. Reinforced Cement Concrete Plain cement concrete has very low tensile strength. To improve the tensile…

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Characteristics of an ideal reinforcing material

Content of this article : Characteristics of an Ideal Reinforcing Material,Steel as Reinforcing Material has high tensile strength and elasticity.,Deformed Bars and Twisted Bars Characteristics of an Ideal Reinforcing Material The characteristics of an ideal reinforcing material are: It should be easily and cheaply available in bulk. It should possess high tensile stress and elasticity. Its thermal coefficient of expansion should be nearly equal to that of concrete to minimise thermal stress. It should have a long and durable life so that it can render service for longer time. It should be free from loose mill scales, loose rust and coat of paints, which reduce the bond. It should be capable of forming perfect bond or grip with concrete so that stresses are transferred from one material to the other.    Steel as Reinforcing Material The steel is commonly used as reinforcing material due to its following qualities. It possesses…

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ADVANTAGES AND DISADVANTAGES OF CONCRETE

ADVANTAGES AND DISADVANTAGES OF CONCRETE Content of this article: Advantages of concrete,Disadvantages of concrete,advantages and disadvantages of concrete,inert material acts as a filler and the binding materials.Rcc Concrete is considered as a chemically combined mass where the inert material acts as a filler and the binding materials act as a binder. The most important binding materials are cement and lime. Inert materials used in concrete are termed as aggregates. Most common aggregates are sand, brick chips, stone chips, gravels, shells etc. The concrete plays a very important role in all branches of civil engineering. Concrete is an inexpensive, quick and durable way to complete many construction projects. However, there are advantages and disadvantages associated with this material. For example, while concrete becomes stronger and more durable with time, it is susceptible to water and freezing temperatures, meaning that water can seep into cracks and cause damage to the concrete. There…

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Properties of concrete in plastic and hardened state

Contents of this article:properties of concrete in plastic state,properties of concrete in hardened state,concrete in setting state,workability,water cement ratio. Properties of Concrete in Plastic State concrete in Plastic State When the concrete is first mixed it is like bread dough . It is soft and can be worked or moulded into different shapes. In this state concrete is called PLASTIC. Concrete is plastic during placing and compaction. The most important properties of plastic concrete are workability and cohesiveness. Properties of Concrete in Hardened State   concrete in Hardened State After concrete has set it begins to gain strength and harden. The properties of hardened concrete are strength and durability. Hardened concrete will have no footprints on it if walked on.     concrete in Setting State   Concrete then begins to stiffen. The stiffening of concrete, when it is no longer soft, is called SETTING. Setting takes place after compaction…

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Equivalent and effective Lengths of Columns

The effective column length can be defined as the length of an equivalent pin-ended column having the same load-carrying capacity as the member under consideration.The smaller the effective length of a particular column,the smaller its danger of lateral buckling and the greater its load carrying capacity. It must be recognized that column ends in practice are neither perfectly fixed nor perfectly hinged. The designer may have to interpolate between the theoretical values given, to obtain a sensible approximation to actual restraint conditions.   Equivalent Lengths of Columns for Various End Conditions S.No. Type Effective Length of member I 1. Effectively held in position and restrained in direction at both ends. 0.67L 2. Effectively held in position at both ends and restrained in direction at one end. 0.85L 3. Effectively held in position at both ends but not restrained in direction L 4. Effectively held in position and restrained in direction…

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Definition and object of Surveying and levelling

Definition and object of Surveying and levelling Learn Surveying, definition of surveying,Definition of levelling, Object of Surveying Definition of Surveying Surveying is the art of determining the relative positions of points on, above or beneath the surface of the earth by means of direct or indirect measurements of distance, direction and elevation. It also includes the art of establishing points by predetermined angular and linear measurements. The application of surveying requires skill as well as the knowledge of mathematics, physics, and to some extent, astronomy. Definition of Levelling Levelling is a branch of surveying the object of which is (i) to find the elevations of points with respect to a given or assumed datum, and (ii) to establish points at a given elevation or at different elevations with respect to a given or assumed datum. The first operation is required to enable the works to be designed while the second…

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FUNCTIONS AND TYPES OF FOUNDATIONS

Learn FUNCTIONS AND TYPES OF FOUNDATIONS,foundation,types of foundation,spread foundation,pile foundation,friction pile,end bearing pile Foundation The lowest part of a structure which transmits the weight of the structure together with live loads, seismic and wind pressure to the ground surface on which the structure rests, ensuring its safe bearing capacity, is called foundation. To increase the stability of the structure, foundations are generally placed below the ground level. Functions of Foundations Following are the main functions of foundations : To transmit and distribute the total load of the struc­ture to a larger area of underlying support. To prevent differential settlement of the structure. To provide stability to the structure. Types of Foundations The following are the main types of foundations : Spread Foundations. The total load of the structure transmitted to the base of the structure is spread over a large area by a spread foundation. The width of the wall…

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