Outline • Plan reading – Scale – Terminology
drawing • Structural drawing – Steel – Concrete
Outline • Plan reading – Scale – Terminology
drawing • Structural drawing – Steel – Concrete
Plan Reading include: • Types of scales include: – Engineers’ • Decimal • 10, 50, 20, 40, 30, 60
– Architects’ • 2 scales per edge • Feet-inches • 1, 1/2, 1/2, 1/4, 1/4, 1/8, 1/8, 3/4, 3/4, 3/8, 3/8, 3, 11/2 11/2,, Regu Regula larr, 3/32 3/32,, 3/16
– Metric’
Engineer’s Scale This means 30 gradations in the sale per inch
3 miles 300' 30' 30"
The Engineer's Scale expresses measurements as a ratio, depending on the ratio assigned.
3" 1"
Ac Actual Length
NTS: Not to scale
NTS: Not to scale
Engineer’s Scale 660 feet There are always 10 gradations between units
1"
Ac Actual Length 00
00
00
Given SCALE 1”=300’ …then line that measures 1 actual inch represents 300 feet on drawing
NTS: Not to scale
Engineer’s Scale
325 feet
Given SCALE 1”=300’
Engineer’s Scale
NTS: Not to scale
Don’t confuse 1:30 with 1”=30’ SCALE 1”=30’ Paper Units : Actual Units PU AU
=
1” 30’
=
1”
= 360”
0.0028
Reduction scale in ACAD
Architectural Scale • The scale means how many inches per foot, so a ¾ scale means that ¾ inch equals one foot • Each scale read from “0” closest definition • Each unit represents 12 inches
Architectural Scale Given SCALE 3/4”=1’ This means ¾” = 1”
…this is a reduction scale..
Note this is always divisions of 1 foot. So, since this is sub-divided unit into 24 units. each 2 units is 1 inch.
Architectural Scale Note that the sub-divided unit is divided into 12 units. Therefore, each unit is 1 inches.
It measures approx 14’ -5”
Given SCALE 1/4”=1’ …then line that measures 1 paper inch represents 4 actual feet
In-class Exercise
Plan View (Top View)
Shows the horizontal alignment
Stationing • Given as: – STA + FT (or m)
• Typically: – stations in 100 ft or 100 m
• So the distance from STA 1+55 to 2+33 – – – –
(assuming 100 foot stations) (100-55) + (33) = 78 feet OR 233-155 = 78 feet
1
2
3
Profile View (Front View)
Shows the vertical alignment
Plan and Profile
Slopes • Angles sometimes given as V:H, read as “X on X” slope (RISE:RUN). 1:5 1V 5H
Percent Slopes • Angles sometime given as % slope. A 2% means for every 100 unit horizontal, there is a 2 unit change in the vertical. -2% 2’ 100’ 100’ 2’ +2%
Elevations
A building elevation is typically labeled in relation to the compass direction it faces; the direction from which a person views it.
Elevations
Cross Section Centerlines (CL) indicate center of alignment of structure
link Cross Section of Deck and Hangers Source: Dorman Long (1932) Sydney Harbour Brige. Dorman Long & Co. Ltd., p35, http://sydney-harbour-bridge.bos.nsw.edu.au/engineering- studies/engineering-graphics.php
Section View
In-class Exercise • What if I don’t know the scale or the drawing looks to have copied/zoomed, how could use a scale (ruler) to determine an object? • Task: Make your own scale to measure the distance between DH3-97 and DH-1-97
Approximating scale • Find a dimension on the plan sheet, measure it • Create your conversion based on PU:AU PU AU
3.78” =
76 m
AU (m) =
76 m
PU (in)
3.78 in
76 m So if I measure 3.15” on 3.15 (in) AU (m) = paper…. 3.78 in AU (m) = 63.33
Structural Drawings • Structural drawings include: – – – –
Foundation plans Wall sections and framing details Structural steel framing and details Beam and column drawings and details
• Materials – – – –
Wood Steel Concrete Masonary
Approach • Nearly all of the drawing principles that you have learned apply to structural drawing • AutoCAD has “tools” built-in to help you draw elements faster
Structural Steel • Two things to design/draw – Structure
Beam
• Beams and columns • Size, orientation, shape, length, placement
– Connections • Bolted, welded, or riveted (not really used)
n m u l o C
n m u l o C
Engineering design drawings • Show the overall dimensions of the structure including: – Locations of columns, beams, angles and other shapes – Sizes of structural members – Detail in the form of cross sections, special connections required, and notes
Structural Steel Shapes
•
•
Structural steel is available in many standard shapes Most CAD programs have structural shapes symbol libraries available
Video Link Nominally, depth and mass/unit, so shape is 14” tall 53#/ft
Manual of Steel Construction
Structural Steel Dimensions in feet and inches, no ” symbol
Plan View of One Floor
Shop drawings • Consist of detail drawings of all parts of the entire structure showing exactly how the parts are to be made • These drawings show all dimensions necessary for fabrication, usually calculated to the nearest 1/16”
Piece Marks • A system is used to mark each piece that is separately handled • This mark is called a piece mark and should be shown wherever the member appears on the drawings
Connections • Main members are joined together in the field to build a structure and most joints are welded connections to the main members • Riveting is seldom used as a connection but you may find reference to riveted joints in original plans
Welding • Welding is a common method for connecting steel members of buildings and bridges • The principal methods of welding are: – Gas welding – Arc welding – Resistance welding
Types of Welded Joints •
•
•
•
•
Butt joint Corner joint T-joint Lap joint Edge joint
Types of Basic Welds & Symbols
Complete Welding Symbol
Fillet Welds
The arrow points to the joint where the weld is to be made. If weld symbol is below line, weld is made on leader arrow side. If above, opposite arrow. If both above and below, then both sides of joint.
CAD Welding Templates • Welding templates can simplify drawing welding symbols by hand • They have all the forms needed for drawing the arrow, weld symbols, and supplementary symbols
Simple Beam Connection
In-class Exercise
Has Design Been Constructed?
1. On sheet GW-34, mark locations of welds. 2. Review the WSDOT plans for the bridge. Based on the photos shown here, find as many clues that answer this question
Concrete • Concrete is made by mixing sand, gravel, or other aggregates with Portland cement and water • Concrete is very good in compression, but weak in tension • To solve this, embedded steel reinforcing bars are added to concrete – “Reinforced concrete”
• Prestressed concrete, – steel is pretensioned before the superimposed load is applied
Reinforced Concrete Drawings • Size of and shape of members •
Concrete material pattern shown in section
• Placement of reinforcing steel in section and plan views – Steel reinforcing shown as solid lines or filled circles depending on view or section AR-CONC HATCH pattern in ACAD
SOLID HATCH pattern in ACAD
Reinforced Concrete Drawings
Spiral Column Reinforcing
Jackson School Road O’xing
Jackson School Road O’xing
Bent 2
