# STRUCTURES I

## MODULE UNIT DESCRIPTION

This module involves the analysis of forces and design of structural elements encountered in construction.

## PURPOSE

The module unit is designed to equip the trainee with knowledge skills and attitudes in the analysis of forces of structural elements.

## SPECIAL REQUIREMENTS

The trainee should have a KCSE with knowledge in Mathematics and Physics.

## GENERAL OBJECTIVES

At the end of the module unit, the trainee should be able to:

1. Understand the behavior of structural materials
2. Understand principles of analyzing forces in determinate and in-determinate
3. Appreciate need for analysis in the design of building structural members
4. Generate structural drawings from the structural designs

## MODULE UNIT SUMMARY AND TIME ALLOCATION

 CODE SUM-MODULE UNIT CONTENT TIME(HRS) 21.1.1 Definitions Calculations Hooke’s Law 9 21.1.2 COMPOSITE MATERIALS Descriptions Compatibility Equations Equilibrium Equations Determination of composite materials 7 21.1.3 TEMPERATURE STRESSES AND STRAIN Temperature Stress equation Application of the formula 5 21.1.4 TYPES OF SUPPORRTS AND LOADINGS Simply supported Continuous supports Cantilever Concentrated loads Uniformly distributed loads Varying loads 4 21.1.5 Shear force values Bending moment values Plotting the shear force and bending moment diagrams Point of contra flexure 7 21.1.6 Centroid Radius of Gyration Section Modulus (Z) Moment of Inertia (I) 6 21.1.7 Elements of simple bending General Expression Behavior of forces 5 21.1.8 Types of frames Magnitude and direction Methods 7 21.1.9 General expression of shear Determination of shear stress in beam sections Shear stress distribution diagrams 6 21.1.10 Slenderness ratios of long an short columns Concentric and eccentric loadings in columns Rankine – Gordon formula Critical loads on columns 6 TOTAL 55

## MODULE UNIT: PROPERTIES OF MATERIALS

### Specific Objectives

By the end of the sub-module unit, the trainee should be able to:

1. define terms used in properties of materials
2. calculation of stress and strain
3. state Hooke’s law
4. describe the stress – strain relationship

### Content

• Definitions

-plasticity -elasticity -stress -modulus of elasticity -bulk modulus -yield modulus

• Calculations

-stress -strain

• Stating Hooke’s law
• Describing the stress-strain relationship
• Sketching the stress-strain graph
• Modulus of rigidity
• Working stress and ultimate stress
• Factor of safety

### PRACTICE

#### Specific Objectives

By the end of the sub-module unit, the trainee should be able to:

1. Set the apparatus for stress, strain experiment
2. Carry our experiment for stress and strain
3. Carry out tensile test for ferrous metals
4. Plot the stress strain graph
5. Calculate stress and strain