Sunday 29 September 2013

Fundamentals of Shed Design Pt#1

The fundamental tasks for structural design of just about any building structure can be classified as follows:

  1. Dimension & Geometry
  2. Design Actions
  3. Design Action-Effects
  4. Member Design/Specification
  5. Connection Design/Specification
  6. Footing Design/Specification


Generic Connection Details cold-formed Steel Sheds and Canopies

BUILDING INDUSTRY EXAMPLE OF OCCUPATIONAL TASKS

Tracer Receives CAD file of building floor plan and elevations. Copies file and provides with name to match company standards. Deletes irrelevant data, modifies layers as required to meet company/project standards. Inserts drawing sheet, fills in title block and otherwise sets up basis of drawing.

Drafter Receives drawing from tracer, decides additional sections, views and details. Then produces additional drawings as necessary.

Design-Drafter
Receives drawings from drafter then designs dependent systems and prepares additional drawings. Includes structural drawings, mechanical services (HVAC, water supply, sanitary drainage), electrical services (power supply, lighting, communications, data, security).

Technician Designer/Analyst Reviews design-drafters drawings or produces themselves. Uses Design handbooks, manufacturers catalogues, and codes of practice to evaluate the suitability of the drawn design-solutions. For example size air conditioning units and ducting, size water pipes and sanitary drainage pipes, size and locate vents to drainage system. Size power cables, lighting and switching cables, determine number of circuits and design circuit layout. Size simple beams, columns and connections.

Engineering Officer (Design/Analyst) Single air conditioning duct not suitable, and more complex network or ducts proposed, similarly for water pipes and sanitary drainage. Electrical system demands more than normal mains supply can provide, sophisticated control systems and programming required, possibly small substation or emergency power supply. Structural forms less routine, instead of applying routine formulae need to apply routine procedures. Otherwise involved in developing design tools for technician designer/analysts. Designers do not want to be held back by the evaluation of the suitability they want to get on with applying suitable solutions to their design problems.

Engineering Technologist (Designer/Analyst) Principally employed developing design tools for the lower level designers. Typically should not be involved in day to day design projects unless the employing enterprise specialises in high end design projects. There are very few high end design projects; our industrial society already exists, and therefore all our industrial systems have been designed and constructed already. The primary requirement is therefore to APPLY the solutions and improve the solutions, and improve our ability to apply and supply the solutions.

Engineer (Designer/Analyst) Generally should not be required on a building project. However new scientific research may provide economies not previously available and demand the skills of engineers until specialist technicians have been trained and appropriate design tools developed.

Architect (Designer/Analyst) Architects may have designed the original floor plan provided to the tracer in the first instance, but more likely a design-drafter produced the original floor plan. Internal fixtures for the building maybe design by an industrial product designer, but also most likely designed by design-drafters or even drafters.

CONCLUSIONBasically once an architect has developed a suitable building-solution for a particular application, the solution can be applied by design-drafters or drafters to a multitude of similar situations. When it comes to needs, supply is more important than any objections an architect may have about aesthetics and repetition. Besides repetitive buildings tend to acquire individuality, as they evolve with the end-users usage. Fundamentally therefore the vast majority of our technological systems should be within the scope of technicians to design and evaluate. Tracers, Drafters and Design-Drafters should be capable of being trained on the job, and pursuit of self-study. They should be able to use books on engineering graphics, technical drawing, manufacturers catalogues, prescriptive codes of practice and experience gained from drafting other designers design-solutions to develop their own design-solutions for given design problems.

ARCHITECTS / INDUSTRIAL PRODUCT DESIGNERS

Historically industrial product design was developed by architects, applying the principles of design outside the arena of the built environment. Architects have less focus on the detailed quantitative assessment of designs and more focus on the qualitative aspects of design. The architect is equivalent to the engineer, with lower level technologists, building designers and architectural drafters below. Architects normally employ the services of engineering consultancies for detailed quantitative assessment of design-solutions.

ENGINEER (DESIGNER/ANALYST)

Minimum education 4 year Bachelor of Engineering (or equivalent) in the design and enabling sciences. The design problems cannot be solved by APPLYING known solutions, nor by ADAPTING such known solutions, ORIGINAL solutions are required. Evaluation of the design-solutions is beyond the scope of known design-science and additional empirical research and original evaluation models need to be determined. Once the design-science has been developed it can be passed down the line, so that the design-solutions can be APPLIED and ADAPTED by others.

ENGINEERING TECHNOLOGIST (DESIGNER/ANALYST)

Minimum education 3 year Bachelor of Technology (or equivalent) in the design and enabling sciences. They principally ADAPT routine solutions to the circumstances of new projects. Routine design-solutions are unsuitable and the methods of assessment/evaluation need to be adapted to fit the design-solution proposed. Some potential exists for novel and original solutions and empirical research.

ENGINEERING OFFICER (DESIGNER/ANALYST)

Minimum education of 2 year Associate Diploma (or equivalent) in the design and enabling sciences. Like the technician, they APPLY routine solutions to new projects, the solutions however are more complex and flexible, and some potential exists for ADAPTING the solutions to new circumstances.

TECHNICIAN DESIGNER/ANALYST

The lowest level formally educated design/analysts possessing a minimum of a 1 year (full-time equivalent) certificate in design-science or other enabling-sciences. With their knowledge of design-science they are able to develop design-solutions and evaluate suitability of such solutions using routine assessment methods. They can determine form and function, make qualitative assessments, and simple quantitative assessments. They APPLY routine solutions to new projects, and are capable of deciding that such solutions are inappropriate.

DESIGN-DRAFTER

The experience drafter with the ability to conduct dimensional and geometrical design and simple functional design. Is able conduct design where the design-solution is a routine assembly of commonly available components and the principal or initial design requirement is achieving fit. Initial design-solutions may require assessment/evaluation by higher level designer/analysts. (This is likely the highest level attainable without a formal education in design-science)

DRAFTER

In a design organisation the position is principally a trainee position for design-drafters. In other organisations principally concerned with documentation and illustration, drafters are career positions. In a design organisation it is the next step up from tracer. The drafter is responsible for organising the graphical information for a project. The drafter determines drawings, views, sections and details required, and decide on symbolic or pictorial format for the drawings. Given design sketches (at least two complete orthographic views), produces formal drawings to drafting standards, and can generate all additional views, sections that maybe required to clearly communicate the design concept and intent.

JUNIOR/ TRACER/COPY DRAFTER

Primarily a trainee, principal task is to be present in the office and assist where required with all low level tasks in order to get over all experience of what the business of a design office is about. It is the first stepping stone towards becoming a drafter. The individual either traces or manually copies the contents of one drawing sheet onto another drawing sheet. This develops skills in reading drawings, and producing drawings, and also provides foundation knowledge in the area of the product being designed. When using CAD the tracer will copy files, delete layers, rename objects, and otherwise modify the style/format of a copy of an existing drawing to meet current project specific CAD standards.

On Professions

I have little interest in professions. I basically consider that in the main professionals have hijacked the human knowledge base and are holding it to ransom for extortionate fees, via the use of fear uncertainty and doubt (#fud). People don't find out that the professional knows less than they do until they have paid the fee, this is particularly the case when it comes to management consultants.

Humans are supposed to be the most intelligent and adaptable creatures on earth. Yet teachers having told the class this, proceed to treat their pupils like sheep, and turn them into inflexible cogs supposedly required by the machinery of industrial society. It all fits with a mechanistic view of the world. Chop and dice up knowledge and tasks.

The knowledge required to survive in the world of tomorrow cannot be based on that of yesterday. it is not professionals who have continuing professional development imposed upon them that we need. It is individuals who seek to learn, and better understand the future that we are heading towards.
A professional is simply a cog required by some established system. Professionals are highly specialised inferior subspecies of humanity. Aim to be human rather than a professional.

Study Guide: Sample Programme #10

Table 10: Sample Programme
SubjectFull Work Load [hours]            
Art
Philosophy
Language
Mathematics
History
Geography
Science
Astronomy
Geology
Biology
Chemistry
Physics
Technology
Design
70
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
20
Product Technology: Building Construction
20
Management, Business and Office Procedures
20
Legal Framework
20
Total
300

Study Guide: Sample Programme #9

Table 9: Sample Programme 9
SubjectFull Work Load [hours]            
Design
950
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
100
Product Technology: Building Construction
100
Management, Business and Office Procedures
100
Legal Framework
100
Total
1500
{Certificate V programme: 50 weeks at 30 hours/week or 50 hours/week for 30 weeks}

Study Guide: Sample Programme #8

Table 8: Sample Programme 8
SubjectFull Work Load [hours]            
Design
650
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
100
Product Technology: Building Construction
100
Management, Business and Office Procedures
100
Legal Framework
100
Total
1200
{Certificate IV programme: 50 weeks at 24 hours/week or 50 hours/week for 24 weeks}

Study Guide: Sample Programme #7

Table 7: Sample Programme 7
SubjectFull Work Load [hours]           
Design
350
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
100
Product Technology: Building Construction
100
Management, Business and Office Procedures
100
Legal Framework
100
Total
900
{Certificate III programme: 50 weeks at 18 hours/week or 50 hours/week for 18 weeks}

Study Guide: Sample Programme #6

Table 6: Sample Programme 6
SubjectFull Work Load [hours]            
Design
150
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
50
Product Technology: Building Construction
75
Management, Business and Office Procedures
100
Legal Framework
75
Total
600
{Certificate II programme: 50 weeks at 12 hours/week or 50 hours/week for 12 weeks}

Study Guide: Sample Programme #5

Table 5: Sample Programme 5
SubjectFull Work Load [hours]            
Design
100
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
50
Product Technology: Building Construction
50
Management, Business and Office Procedures
100
Legal Framework
50
Total
500
{50 weeks at 10 hours/week or 50 hours/week for 10 weeks}

Study Guide: Sample Programme #4

Table 4: Sample Programme 4
SubjectFull Work Load [hours]            
Design
70
Technical Drawing & Engineering Graphics
150
Process Technology: Manufacturing & Construction           
20
Product Technology: Building Construction
20
Management, Business and Office Procedures
20
Legal Framework
20
Total
300
{Certificate I Programme: 50 weeks at 6 hours/week
or approximately 1 day per week for 50 weeks,
or 30 hours/week for 10 weeks,
or 10 hours/week for 30 weeks.}

Study Guide: Sample Programme #3

Table 3: Sample Programme 3
SubjectFull Work Load [hours]            
Design
10
Technical Drawing & Engineering Graphics
75
Process Technology: Manufacturing & Construction           
10
Product Technology: Building Construction
10
Management, Business and Office Procedures
10
Legal Framework
10
Total
125
{50 weeks at 2.5 hours/week programme}

Study Guide: Sample Programme #2

Table 2: Sample Programme 2
SubjectFull Work Load [hours]            
Design
5
Technical Drawing & Engineering Graphics
25
Process Technology: Manufacturing & Construction           
5
Product Technology: Building Construction
5
Management, Business and Office Procedures
5
Legal Framework
5
Total
50
{1 week programme}

Study Guide: Sample Programme #1

Table 1: Sample Programme 1
SubjectFull Work Load [hours]            
Design
2
Technical Drawing & Engineering Graphics
4
Process Technology: Manufacturing & Construction           
1
Product Technology: Building Construction
1
Management, Business and Office Procedures
1
Legal Framework
1
Total
10
{1 day programme}

Proposed Study Guide

An unofficial guide to learning the technical science behind technical: planning, design and management.

For further information refer to Australian Qualification Framework (AQF) , and for national training packages and required competences across design and engineering occupations refer to http://www.training.com.au . Not sure what is avialable from training.com.au, this site has taken over from  the National Training and Information Service (NTIS). The training packages provided useful details for reference when preparing a report for recognition of prior learning (RPL). Under the AQF it is not necessary to attend a college/institute of Technical and further education (TAFE) or a registered training organisation (RTO) and waste time studying what you already know: simply need to provide evidence of having achieved the required competences, and get an RTO or similar to accept recognition of prior learning prior to issuing the AQF award. For persons with a great deal of on the job learning and training and no formal certification of such learning, RPL enables obtaining the qualifications which may be required to get promotion or a new job. Especially important where businesses have shutdown, and employees now having difficulty getting back into   the same type of work because they don't have the right piece of paper.

Saturday 28 September 2013

Sample vba code

Sample code used in schTechLIB. The code is for transforming the stepped wind loading into a uniform load.

Option Explicit

#Const MyDebugOn = 0

'Determine equivalent UDL for each slope
'for stepped distribution along doubly pitched
'frame when alpha < 10
'eq UDL based on distributing total load on rafter along length

Function equivUDL0(alpha As Double, He As Double, _
                   BldSpan As Double, BldLen As Double, _
                   roofplane As Integer) As Double
                      
  Dim ht As Double
  Dim dwe(5) As Double
  Dim d As Double
  Dim ratio As Double
  Dim udl(5) As Double
  Dim Cp(5) As Double
  Dim loadEdge(5) As Double
  Dim halfwdth As Double
  Dim rafterlen As Double
  Dim sumudl1 As Double, sumudl2 As Double
  Dim i As Integer
  Dim J As Integer
  Dim k As Integer
  
    
  halfwdth = BldSpan / 2
  rafterlen = halfwdth / Cos(ToRadians(alpha))
  ht = He + halfwdth * Tan(ToRadians(alpha))
  k = halfwdth / He
  
  
  '{i=0} 0.5h
  '{i=1}   1h
  '{i=2}   2h
  '{i=3}   3h
  '{i=4}  >3h = bldspan
  '{i=5}  halfwdth
  
  dwe(0) = 0.5 * He
  Cp(0) = Get_Cpe_UD(0, alpha, He, ht, BldSpan, BldLen, dwe(0))
  
  dwe(4) = BldSpan
  Cp(4) = Get_Cpe_UD(0, alpha, He, ht, BldSpan, BldLen, dwe(4))
  
  dwe(5) = halfwdth
  Cp(5) = Get_Cpe_UD(0, alpha, He, ht, BldSpan, BldLen, dwe(5))
  
  For i = 1 To 3
    dwe(i) = i * He
    Cp(i) = Get_Cpe_UD(0, alpha, He, ht, BldSpan, BldLen, dwe(i))
  Next i
  
  J = 0
  k = 0
  For i = 0 To 5
    If dwe(i) < halfwdth Then
       loadEdge(i) = dwe(i) / Cos(ToRadians(alpha))
       If i = 0 Then
         udl(i) = loadEdge(i) * Cp(i)
       Else
         udl(i) = (loadEdge(i) - loadEdge(i - 1)) * Cp(i)
       End If
       J = i
    ElseIf dwe(i) = halfwdth Then
       loadEdge(i) = dwe(i) / Cos(ToRadians(alpha))
       udl(i) = (loadEdge(i) - loadEdge(J)) * Cp(i)
    ElseIf dwe(i) = BldSpan Then
       If k <> 0 Then 'building assumed to greater than 0.5h wide
         loadEdge(i) = (BldSpan - dwe(k)) / Cos(ToRadians(alpha))
         udl(i) = loadEdge(i) * Cp(i)
       Else
         loadEdge(i) = rafterlen
         udl(i) = loadEdge(i) * Cp(i)
       End If
    Else
       If i = J + 1 Then
         loadEdge(i) = (BldSpan - dwe(i)) / Cos(ToRadians(alpha))
         udl(i) = (rafterlen - loadEdge(i)) * Cp(i)
       Else
         loadEdge(i) = (BldSpan - dwe(i)) / Cos(ToRadians(alpha))
         udl(i) = (loadEdge(i - 1) - loadEdge(i)) * Cp(i)
       End If
       k = i
    End If
    'Debug.Print i; dwe(i); cp(i); loadEdge(i); udl(i)
  Next i
  
  'Debug.Print "rafter 1: ..."
  sumudl1 = 0
  For i = 0 To J
    sumudl1 = sumudl1 + udl(i)
    'Debug.Print udl(i)
  Next i
  'Debug.Print udl(5)
  sumudl1 = (sumudl1 + udl(5)) / rafterlen
  
  'Debug.Print "rafter 2: ..."
  sumudl2 = 0
  For i = J + 1 To 3
    sumudl2 = sumudl2 + udl(i)
    'Debug.Print udl(i)
  Next i
  'Debug.Print udl(4)
  sumudl2 = (sumudl2 + udl(4)) / rafterlen
  
  If roofplane = 1 Then
    equivUDL0 = sumudl1
  ElseIf roofplane = 2 Then
    equivUDL0 = sumudl2
  End If

End Function


'-------------
'GABLE ROOF
'-------------
'Determine equivalent UDL for each slope
'for stepped distribution along doubly pitched
'frame when alpha < 10
'eq UDL based on BM due to load on rafter equal to BM for UDL
Function equivUDL0m(alpha As Double, He As Double, _
                   BldSpan As Double, BldLen As Double, _
                   roofplane As Integer, BMBasis As Boolean) As Double
                      
  Dim ht As Double
  Dim dwe(5) As Double
  Dim Cp(5) As Double
  Dim loadEdge(5) As Double
  Dim udl(1 To 5) As Double
  
  Dim ndx(5) As Integer
  
  Dim w(1 To 5) As Double
  Dim a(1 To 5) As Double
  Dim b(1 To 5) As Double
  
  Dim d As Double
  Dim ratio As Double
  
  Dim halfwdth As Double
  Dim L As Double
  Dim sumudl1 As Double, sumudl2 As Double
  
  Dim i As Integer
  Dim J As Integer
  Dim k As Integer
  Dim n As Integer
  
  Dim temp As Double
  Dim udl2 As Double
    
    
  'Debug.Print "eq UDL version  2 ..."
  halfwdth = BldSpan / 2
  'Debug.Print "Half width = "; halfwdth
  
  L = halfwdth / Cos(ToRadians(alpha))
  ht = He + halfwdth * Tan(ToRadians(alpha))
      
  
  For i = 1 To 5
    a(i) = 0
    b(i) = 0
    w(i) = 0
  Next i
  
  '{i=0} 0.5h
  '{i=1}   1h
  '{i=2}   2h
  '{i=3}   3h
  '{i=4}  halfwdth
  '{i=5}  >3h = bldspan
 
  'Determine distance from Windward Edge
  'to far side of load region
  dwe(0) = 0.5 * He
  For i = 1 To 3
    dwe(i) = i * He
  Next i
  dwe(4) = halfwdth
  dwe(5) = BldSpan
  
  
  'Insert halfwdth in position of correct ascending order
  i = 0
  Do While dwe(i) < halfwdth And i <= 3
    i = i + 1
  Loop
  k = i
  
  ndx(5) = 5
  For i = 0 To 4
    If i = k Then
      ndx(i) = 4
    ElseIf i < k Then
      ndx(i) = i
    Else
      ndx(i) = i - 1
    End If
  Next i
  
  'Determine Cp
  'Debug.Print "dwe, cp"
  For i = 0 To 5
    Cp(i) = Get_Cpe_UD(0, alpha, He, ht, BldSpan, BldLen, dwe(ndx(i)))
    'Debug.Print dwe(ndx(i)), cp(i)
  Next i
  
  
  'Determine distance "a" to start of load
  If roofplane = 1 Then
    a(1) = 0
    b(1) = dwe(ndx(0)) / Cos(ToRadians(alpha))
    w(1) = Cp(0)
    
    i = 2
    Do While dwe(ndx(i - 2)) < halfwdth And i <= 5
      a(i) = dwe(ndx(i - 2)) / Cos(ToRadians(alpha))
      b(i) = (dwe(ndx(i - 1)) - dwe(ndx(i - 2))) / Cos(ToRadians(alpha))
      w(i) = Cp(i - 1)
      i = i + 1
    Loop
    n = i - 1
'    Debug.Print "n = "; n
    
'    Debug.Print "a:b:w"
'    For i = 1 To 5
'      Debug.Print i, a(i), b(i), w(i)
'    Next i
  
 
  ElseIf roofplane = 2 Then
 
   
    i = 1
    J = k
    Do
      If halfwdth <= dwe(ndx(J)) And dwe(ndx(J)) <= BldSpan Then
         If i = 1 Then
            a(1) = 0
            b(1) = (halfwdth - (BldSpan - dwe(ndx(J + 1)))) / Cos(ToRadians(alpha))
            w(1) = Cp(J)
         Else
            a(i) = (halfwdth - (BldSpan - dwe(ndx(J)))) / Cos(ToRadians(alpha))
            b(i) = (dwe(ndx(J + 1)) - dwe(ndx(J))) / Cos(ToRadians(alpha))
            w(i) = Cp(J + 1)
         End If
         'Debug.Print i, j
      End If
      i = i + 1
      J = J + 1
    Loop Until i > 5 Or J > 4
    n = i - 1
    'Debug.Print "n = "; n
    
'    Debug.Print "a:b:w"
'    For i = 1 To 5
'      Debug.Print i; a(i); b(i); w(i)
'    Next i
    
  End If
   
  For i = 1 To n
    udl(i) = w(i) * b(i)
    'Debug.Print w(i); b(i); udl(i)
  Next i
 
  sumudl1 = 0
  For i = 1 To n
    sumudl1 = sumudl1 + udl(i)
  Next i

  sumudl1 = sumudl1 / L
  
  If BMBasis Then
   udl2 = eq_udl1(n, w, a, b, L)
   'Debug.Print "eq udl BM basis : ", udl2
   equivUDL0m = udl2
  Else
   equivUDL0m = sumudl1
  End If
  
End Function

Looks like need something which can automatically format, syntax highlight the vba code. Alternatively may have to post the code elsewhere.


Found a syntax highlighter here. Also found this, but didn't like the idea of referencing unknown javascript modules. As far I could tell the first method just generated html code from the source code provided, but I needed to edit slightly to post it here.

Technical Function Library

This is a library of functions for calculations to various Australian structural standards including:


  1. AS1170.2 Wind loading 
  2. AS4100 Steel structures code 
  3. AS4600 Cold-formed steel structures code 
  4. AS1720 Timber structures code 

It also contains a lot of experimental litter. It is an absolute necessity for using all my other spreadsheets. Spreadsheets are useful, but I find vba code more reliable and easier to read when it come to conditional tests, branching, and looping. Spreadsheets are not very reliable when it comes to tabulated calculations nor efficient. In a database management system an equation is defined once for a group of records and then progressively executed on each record. In a spreadsheet the equations have to be defined for each and every record (row) of the spreadsheet and that leads to potential error. It is also easier to expend an array in vba than it is to add extra rows to tables and mesh several tables together. Even if using tables of calculations in a spreadsheet it is easier to call vba functions to achieve greater consistency for each cell calculated, and too hide lots of complex conditional tests behind the scenes. Each different audience and purpose for calculations requires a different presentation, having vba functions provides greater flexibility compared to merely replicating hand written calcs in a worksheet.


Taken from the ExcelCalcs.com website.

Wind Loading

This is an example of wind loading calculations to Australian and New Zealand wind loading code (AS/NZS 1170.2)

schWindAssessment_r02 by Conrad Harrison



This is an MS Excel spreadsheet which can be used to produce similar calculations. Users will need to be familiar with AS/NZS 1170.2 to be able to use it.
Taken from the ExcelCalcs.com website.

The spreadsheet is also dependent on schTechLIB and AS4055. However AS4055 is optional if do not need the equivalent simplified wind classifications for the wind speed and wind pressure as calculated to AS1170.2.

Tuesday 10 September 2013

Fixed!

Seems that CSS code wasn't actually being applied when I tried previously. Edited the code I copy/pasted, and deleted an extra space, then the Apply to Button became active, pressed and applied and immediately fixed. Strange, as I don't believe the width of the header has anything to do with the problem of a large vertical area being made available for a none existent image.

But seems to be fixed. So that was something of a wasted evening.

Stuffed that up!

Edited the header in the layout, to add description. Now lost header altogether. It seems now thinks an image is required in the header. But I don't want an image, especially not one that pushes the blog off screen.

Tried adding and image, and then removing the image hoping it would reset the header. Didn't work. Pressed clear, that didn't seem to work, though not sure what it clears: probably just the current changes. I tried changing to a different template, hoping that would cancel everything and reset, but also didn't work.

I copy/pasted the html edit from this blog, and that for Techstory, and saved to separate html files. Then file compared with UltraEdit and then Beyond Compare.The only real difference is an extra widget in side panel of TechStory, the blog titles, and navigation icon text strings. So idea I had of copy/pasting html code from one to the other, to fix isn't going to help.

Not sure what the html code is doing, but it appears that some where in the system, there is an inappropriate setting for using an image in the header: and by the looks of it, only an image, so no title is displayed.

Checked blogger help system seems several people had similar experience in past 24 hours. The CSS code suggested by someone, doesn't work for me, and I'm not sure what relevance it is to the problem.

The problem appears to be that the editor dialogue box for the header in the layout editor is generating incorrect data settings, and the html nested 'if' statements are consequently executing code for image only display.