saher.gis@gmail.com

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Engr. Faisal Nadeem Saher

PhD Research Scholar, UMP

LESSON OUTCOME

At the end of the class students should be able to:

describe type of drawing and explain civil engineering drawing

discuss the important of engineering drawing to engineers

Identify elements in drawing

Typical Construction Project Life Cycle

PARTIES IN CONSTRUCTION INDUSTRY

CONSTRUCTION INDUSTRY

FINANCIERS

AUTHORITIES

CLIENT/OWNER/DEVELOPER

CONSULTANT

CONTRACTOR

-ENGINEERS - ARCHITECT - QS etc

PROFESSIONALS

• ENGINEERS

- aspire to design structures that are safe and sound which can withstand adverse circumstances and conditions such as soil erosion, earthquakes etc

• ARCHITECT

- committed to creative and imaginative design concepts that are aesthetically pleasing

INTRODUCTION

• Drawing is the effective method to present the proposed design

TYPE OF DRAWING

• SKETCHES/PRELIMINARY DRAWING/CONCEPT DRAWING

• PRESENTATION DRAWING

• WORKING DRAWING: ARCHITECTURAL DRAWING

CIVIL ENGINEERING/STRUCTURAL DRAWING

MECHANICAL & ELECTRICAL DRAWING (M&E)

BUILDING SERVICES DRAWING

ENGINEERING DRAWING

• type of drawing produced by engineer that is technical in nature, used to fully and clearly define requirements for engineered items, and is usually created in accordance with standardized conventions for layout, interpretation, appearance, size, etc

• use by contractor in translating the consultants 2D drawings (design stage) into 3D physical concrete reality

• for material cost and estimating

SUB-DISCIPLINES OF CIVIL ENGINEERING

• CIVIL & STRUCTURAL ENGINEERING

• ELECTRICAL ENGINEERING

• MECHANICAL ENGINEERING

• AND MANY MORE

CIVIL ENGINEERING • INFRASTRUCTURE: - Road Works

- Drainage, Sewerage

- Earthworks, Retaining Wall

- Dam, Reservoir, Water tank, Water retaining structure

• GEOTECHNIC: - Slope Stabilization

- Foundation etc

• SRTUCTURAL WORKS: - Reinforce concrete

- Steel Structure, Timber Structure

- Precast, Pre stressed Concrete, Composite (RC + Steel)

All of the above will have

i. General Arrangement (GA) or layout plan

ii. Sectional, longitudinal section

iii. Details

Example of Drawing: GA

Example of Drawing: Sectional

Example of Drawing: Details

Earthwork drawing need to be prepared before commence work at site

EXAMPLE: ROAD CONSTRUCTION DRAWING

EXAMPLE: SRUCTURAL DRAWING

• Methods to produce goods drawing is very important

• Every drawing produced need to full fill the certain criteria which has been fixed

• This consideration is important to make sure the quality drawings are produced

• Basic understanding: line, code of practice (BS308:PART1:ENGINEERING DRAWING PRINCIPLES. RECOMMENDATION FOR GENERAL PRINCIPLES, BS308 PART 2: RECOMMENDATION FOR DIMENSIONING AND TOLERANCE OF SIZE)

THE NEEDS AND THE IMPORTANT OF ENGINEERING DRAWING

• Why engineer must have the ability to do sketches and understand engineering drawing?

Engineering drawing is the method to store ideas, planning, design proposal etc until it can showed and presented all the related information. Engineer can refer and collect information from this drawing at any time. The drawings also transfer available information to others, to understand and know the proposed design works

During planning stage, engineer will direct contact with aother parties from time to time to show their design and must be in appropriate order. It will be a problem if the engineer cannot communicate bacause of the weakness in producing drawing and sketches, more if the engineer do not know how to read drawing.

The drawing can be produced by using engineering tools

e.g: AutoCAD meanwhile the sketches can be done manually free hand drawn.

MANUAL DRAFTING

• pencil, scale ruler, eraser, 2 triangle set squares (45 and 30-60 deg), set squares, french or flexible curve, protactor, circle and ellipse template, adhesive tape, drawing board, technical pen set, lettering guides, tee square.

Pencil need to keep the lead sharp to produce quality drawing, line with same thickness

Eraser: used soft rubber eraser will not damage the surface of the drawing

Scale ruler- suitable scale ruler in metric or imperial units, flat or triangular in section and tapering towards the ruling edges. 4 scale in flat ruler and 6 scale in triangular ruler

Triangular set squares Small master bow

Units For Malaysian practice, metric units used in the engineering drawing but imperial units seldom used

Metric units

Millimeter (mm)

Centimeter (cm)

Decimeter (dm)

Meter (m)

Kilometer (km)

Imperial units

Inches (in)

Foot/feet (ft)

Yards (yd)

Miles (ml)

Chains (c)

Scales

Scale is the ratio of linear dimension of an element of an object shown in the drawing to the real linear dimension of the same element of an object

1 : 1

Size in drawing: Actual size

SCALES

2 types of scales; Imperial and Metric Scales recommended for used with Metric system

Details- to show all information necessary

1:1 (full size), 1:5 , 1:10

Assembly- to show in detail the construction of buildings 1:20, 1:10, 1:5, 1:25

Ranges- to show basic sizes, system of reference 1:100, 1:50, 1:20

General location- to show position occupied by various spaces in building, general construction and location of principle element

1:200, 1:100, 1:50

Site plan- to locate position of building in relation to setting out point, access, general layout and drainage

1:200, 1:500

Block plan- to identify site and locate outline of building in relation to town plan or other wider contact

1:1000, 1:2000, 1:5000, 1:10000

Scales recommended for used with the imperial system

Arrangement Scale

Full size 1:1

Reduction 1: 1/8, 1:1/4, 1:1/2, 1:3/4

Reduction 1:3/8, 1:3/16, 1:3/32

Enlargement 1:3, 1:16, 1:32, 1:1.5

Use of Scale • Engineering drawing prepared with full size,

enlarge or reduced in size and noted in or near title block

• Designation of a scale consist of the word “scale” followed by indication of its ratio. E.g: Scale 1:1

• Dimension numbers are shown in the drawing correspond to the true size of the object and they are independent of the scale used in creating that drawing

• The word SCALE: NOT TO SCALE in or near title block for example on pictorial drawing.

LETTERING Characters and numbers are important to give notes

and descriptions about the drawing and also specification.

Since the engineering drawing produced by using AutoCAD , thus it should be able to get the correct letter height to suit the paper size. See example below.

Common features of engineering drawings

A variety of line styles are used to graphically represent physical objects. Types of lines

include the following:

VISIBLE - are continuous lines used to depict edges directly visible from a particular angle.

HIDDEN - are short-dashed lines that may be used to represent edges that are not

directly visible.

CENTER - are alternately long- and short-dashed lines that may be used to represent the axes of circular features.

CUTTING PLANE - are thick, medium-dashed lines, or thick alternately long- and double short-dashed that may be used to define sections for section views.

SECTION - are thin lines in a parallel pattern used to indicate surfaces in section views resulting from "cutting." Section lines are commonly referred to as "cross-hatching."

SPEAK UP!

RED, BLUE, BLACK AND MAGENTA LINES??????

VIEWS AND PROJECTIONS

In most cases, a single view is not sufficient to show all necessary features, and several views are used. Types of views include the following:

ORTHOGRAPHIC PROJECTION - show the object as it looks from the front, right, left, top, bottom, or back, and are typically positioned relative to each other according to the rules of either first-angle or third-angle projection.

SECTION - depict what the object would look like if it were cut perfectly along cutting plane lines defined in a particular view, and rotated 90° to directly view the resulting surface(s), which are indicated with section lines. They are used to show features not externally visible, or not clearly visible.

DETAIL - show portions of other views, "magnified" for clarity

AUXILIARY PROJECTION - similar to orthographic projections, however the directions of viewing are other than those for orthographic projections.

ISOMETRIC - show the object from angles in which the scales along each axis of the object are equal. It corresponds to rotation of the object by ± 45° about the vertical axis, followed by rotation of approximately ± 35.264° [= arcsin(tan(30° ))] about the horizontal axis starting from an orthographic projection view

EXAMPLE: ISOMETRIC

EXAMPLE: ORTHOGRAPHIC

• Draw object from two / three perpendicular views

Example: SECTION VIEWS

• If three views are not enough, draw sections needed to completely describe the object.

DIMENSIONING

• A well dimensioned part or structure will communicate the size and location requirements for each feature

• Communications is the fundamental purpose of dimensions

• Designs are dimensioned based on:

i. Basic size and locations of features

ii. Details for construction and for manufacturing

TERMINOLOGY

• Dimension-the numerical value that defines the size, shape, location, surface texture, or geometric characteristic of a feature. Normally, dimension text is 3 mm or 0.125" high, and the space between lines of text is 1.5 mm or 0.0625“

• Basic dimension-a numerical value defining the theoretically exact size, location, profile, or orientation of a feature relative to a coordinate system established by datums. They are identfied on a drawing by enclosing the dimension in a rectangular box. Basic dimensions have no tolerance. They locate the perfect geometry of a part, while the acceptable variation or geometric tolerance is described in a feature control frame

• Reference dimension-a numerical value enclosed in parentheses, providing for information only and not directly used in the fabrication of the part. A reference dimension is a calculated size without a tolerance used to show the intended design size of a part

• Dimension line-a thin, solid line that shows the extent and direction of a dimension. Dimension lines are broken for insertion of the dimension numbers

• Arrows-symbols placed at the ends of dimension lines to show the limits of the dimension, leaders, and cutting plane lines. Arrows are uniform in size and style, regardless of the size of the drawing. Arrows are usually about 3 mm ('/8") long and should be one-third as wide as they are long

• Extension line-a thin, solid line perpendicular to a dimension line, indicating which feature is associated with the dimension

• Visible gap-there should be a visible gap of 1mm ('!l6 ") between the feature's comers and the end of the extension line

• Leader line-a thin, solid line used to indicate the feature with which a dimension, note, or symbol is associated. Leader lines are generally a straight line drawn at an angle that is neither horizontal nor vertical. Leader lines are terminated with an arrow touching the part or detail. On the end opposite the arrow, the leader line will have a short, horizontal shoulder (3 mm or .125" long). Text is extended from this shoulder such that the text height is centered with the shoulder line. Two or more adjacent leaders on a drawing should be drawn parallel to each other

• Diameter symbol – symbol that precedes a numerical value to indicate that the dimensions shows the diameter of a circle ()

• Radius symbol – symbol that precedes a numerical value to indicate that the associated dimensions shows the radius of a circle (R)

DIMENSIONS

Text height and standards used for decimal and millimeter dimensioning

Dimensions used to draw an arrowhead

PLACEMENT

• Dimension placement depends on the space available between extension lines

• When space permits dimension and arrows are placed between the extension lines

• When there is room for numerical value but not the arrows as well, the value is placed between the extension lines and the arrows are placed outside the extension lines

• When there is room for the arrows but not numerical value, the arrows are placed between the extension lines and the value is placed outside the extension lines

• When the space is too small for either arrows and the values both are placed outside the extension lines

LOCATIONS AND ORIENTATION DIMENSIONS

• The unidirectional method of placing text is the current standard practice

LOCATIONS AND ORIENTATION DIMENSIONS

Horizontal text Text on the dimension lines

Text placed between the dimension lines

Dimensions showing the sizes features, height and depth of the part and the diameter of the hole

Size and locations dimensions are used to describe parts for manufacturer

Principles of good dimensioning

• Each feature of an object is dimensioned once and only once. • Dimensions should be selected to suit the function of the object. • Dimensions should be placed in the most descriptive view of the feature

being dimensioned. • Dimensions should specify only the size of a feature. The manufacturing

method should only be specified if it is a mandatory design requirement. • Angles shown on drawings as right angles are assumed to be 90 degrees

unless otherwise specified, and they need not be dimensioned. • Dimensions should be located outside. the boundaries of the object

whenever possible. • Dimension lines should be aligned and grouped where possible to

promote clarity and uniform appearance. • Crossed dimension lines should be avoided whenever possible. When

dimension lines must cross, they should be unbroken. • The space between the first dimension line and the object should be at

least 10 mm • The space between dimension lines should be at least 12 mm.

• There should be a visible gap at least 3mm between the object and the origin of an extension line at .

• Extension lines should extend 3 mm beyond the last dimension line.

• Extension lines should be broken if they cross or are close to arrowheads.

• Leader lines used to dimension circles or arcs should be radial.

• Dimensions should be oriented to be read from the bottom of the drawing.

• Diameters are dimensioned with a numerical value preceded by the diameter symbol.

• Concentric circles should be dimensioned in a longitudinal view whenever possible.

• Radii are dimensioned with a numerical value preceded by the radius symbol.

• When a dimension is given to the center of an arc or radius, a small cross is shown at the center.

• The depth of a blind hole may be specified in a note. The depth is measured from the surface of the object to the deepest point where the hole still measures a full diameter in width.

• Counterbored, spotfaced, or countersunk holes should be specified in a note.

GROUP DIMENSIONS In standard practice, dimensions are grouped on a drawing. Do not use object lines as extension lines for a dimension.

EXTENSION LINE Extension lines should not cross dimension lines, are not broken when crossing object or other extension lines, and are broken when crossing arrows

Guide to draw dimension’s text

Locations and orientation dimensions Fill in the ? Please!!!

CLASS ACTIVITY:WHAT GOES WRONG! PLEASE MAKE IT RIGHT

Layout

Size of drawing paper

A0 and A1 – recommended used in Malaysia and International

Organization and Title Block

Title block should have:

Logo and company name with address

Project title

Name of person who approve, check and draw the drawing

Date: date of 1st drawing was created and issuance of the drawing

Drawing status: preliminary, construction, design, development, for BQ

Notes

Revision table

Standard title block will be used during this course. It will be used for test, assignment and project. Please follow the standard title block accordingly.

Please refer to the attached title block for the example

Layout and presentation of drawing

Logically and neatly arranged to give a balanced layout

Recommended that every drawing sheet shall have a filing margin, title and information panel • Bottom right hand corner of sheet

• Incorporates the job title, subject of drawing, scale, date of drawing, job number, revision suffix, name and adress/ phone no. of architect, M&E engineer, surveyor, QS, C&S engineer

Drawing list Drawing list should be prepared in order to know

the time frame for drawing production and manpower forecast

The standard list of drawing no. with drawing title is prepared in order to have the sequence of number in related to the type of drawing.

Many method can be used. Normally with project managed by project management consultant, the standard requirement to all consultant is spell in PQP

Sketching

The ability to create freehand sketches is an important skill for engineers and designers to acquire

Many design concept and ideas are very difficult to express verbally, so they must express visually

Sketches can be created quickly and used as a powerful aid in communicating technical ideas

Freehand sketching can be learned by lots of practice.

Fundamental of Sketching

1) Proportion

• sketches should be proportional. Square should look like a square and rectangle should look like rectangle

• graph paper is very helpful in sketching proportionally

Steps in Sketching

i. Start by 1st sketching very lightly

ii. Then checking the proportionality of the work

iii. Go back over the line and making corrections if necessary

iv. Then darken in the lines

2) Curves

• Curve shapes are best sketched by first defining points along the curve then lightly sketching the curve between the points. Evaluate the accuracy and smoothness of the curve and make any correction necessary. Then darken in the curve.

3) Circle • Circle can be sketched by sketching perpendicular

centerlines and marking off four point equally spaced from the center point along the centerlines. The distance between the center point and points on the centerlines should be approximately equal to the circle radius

• Draw a second set of perpendicular center line approximately 45 degree to the first. Again mark 4 points approximately equal to the radius of the circle. Sketch a light curve through the 8 points and check the curve accuracy and smoothness. Make any corrections necessary and darken in the circle

4) Ellipse

• An ellipse can be sketched by 1st sketching a perpendicular axis then locating 4 marks on the center lines that are approximately equal to major and minor axis distances. Sketch a light curve, make any correction necessary and darken the elliptical shape.

5) Slot

• To sketch the slot, center line for the 2 end semicircles are located and sketched. 2 additional radius point are added then the overall shape of the slot is lightly sketched. Corrections are made and the final lines are darkened.

EXERCISE

EXERCISE

EXERCISE