As an engineer, you must be able to classify structures according to their FORM and FUNCTIONS.

Composed of structural members, joined together by structural connections is called STRUCTURAL SYSTEM.

The four basic types of structures are :

1. Trusses2. Cables & Arches

3. Frames4. Surface structures

All structural systems are composed of a number of basic structural elements (i.e. Beams, columns, etc.)

1CE381 Structural Analysis I (Supplementary lecture notes) Prepared by: Asst.Prof.Dr.Rifat Reşatoğlu

1. Planning – How will the building be supported?2. Establishing the loads

3. Designing preliminary structural configuration and layout4. Analyzing structural members

5. Selecting preliminary structural members6. Evaluating the preliminary design

7. Redesigning (if needed) – Repeat the above steps as necessary to achieve a safe and efficient design

8. Designing and detailing the structural components

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STRUCTURAL FORM

IDEALIZED MODEL

LOAD TYPES

MATERIAL SELECTION

PRELIMINARY DESIGN

FINAL DESIGN

CONSTRUCTION PHASE

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Within the structural systems, individual structural elements must work together to carry

and transfer the applied loads to the ground.

Examples of structural elements include:

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The buildings should be designed to meet the requirements of the design standards. (with a clearly defined load path, to transfer the forces to the supporting ground).

Cruise of forces can cause damages in LOAD BEARING SYSTEMS.

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FootingColumn

Girder

Beam

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What is tributary area???

Tributary area is the area of the slab which goes to particular beams.

Slab Joist Girder Column Footing

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Tributary Area - Beams

Beams

Girders

Model

Model 8

Tributary Area – Beam/Column Connection

BeamsGirders

Columns

Footings

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Load Paths

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Problem :

The floor system of a building consists of a 15 cm thick reinforced concrete slab resting on four steel floor beams, which in turn are supported by two steel girders. The cross-sectional areas of the floor beams and the girders are 94.8 cm2 and 337.4 cm2, respectively. Determine the dead loads acting on the beams CG and DH and the girder AD. (Unit weight for concrete is 23.6 kN/m3, and for steel 77 kN/m3)

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110 mm concrete slab

A B

C

7 m5 m

D

E F

The floor system of building consists of a 110 mm thick reinforced concrete slab resting on three steel floor beams, which in turn supported by two steel girders.

Determine the dead load acting on the beam CD and the girder AE ?

Steel Girder (AE & BF) ------- A=20000 mm2Steel floor beam (AB, CD, EF)----- A=11000mm2

(Unit weight for concrete is 24 kN/m3, and for steel 77 kN/m3)

Problem :

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