Engaging Structural Engineers in the BIM Process

“………….. engineers work under a fairly structured environment, both in term of organisational structure and workflow….”

This is a sentiment that I have heard from architects again and again in Building Information Modelling case studies and presentations. It is basically a nice way of saying the traditional division of tasks in structural engineering offices is preventing the designs of senior engineer staff from being represented in the model at the appropriate time.

Seven or 8 years ago the same comment would have been would have been true about architectural firms. Senior staff weren’t able to interrogate or add to models, which meant that their ideas weren’t represented in the model in the early stages of design. This meant that the whole concept of the MacLeamy Curve was rendered useless. The design process wasn’t being shifted to an earlier phase, all that was happening was that junior staff were spending a lot of early time on projects, injecting their inexperience into the design, before senior staff produced their more thorough design at the same time as usual.

macleamy-curve-2011

It became apparent, even from outside these companies that some senior staff were being ‘cut out’ of their own internal review process.

These days things have changed, the junior and mid-level architects who became involved with Building Information Modelling 10 years ago now hold senior design positions, and unlike almost every other industry, architectural firms actually laid off some senior staff who were unable to ‘digitally contribute’ post-global financial crisis.

Change of any sort is often unwelcome in Engineering offices, any shirt that is not vertical blue strips is often seen as radical and subversive.  BrisBim (Brisbane’s Building Information Modelling Forum) is currently running a Poll at the moment to see ‘who on your project team has the most positive approach to BIM?’ last time I checked Structural Engineer had two votes.

There are definitely some exceptions to this rule, in Australia and overseas several prominent Engineers have become heavily involved in Building Information Modelling, both technically and as lobbyists for BIM legislation.

The industry best practice is for engineering design and analysis models to be fully integrated with building information models using software such as ETABS or Robot Structural Analysis, where preliminary models are exported from the design software to Revit Structure and then imported back at regular intervals.

What is the ‘plan B’ when this is not possible due to financial, technical or organizational culture limitations? Here are some ideas to get engineers to dip their toes in the water and break down the division between modellers and engineers:

  • Export some simple schedules from Revit to Microsoft Access. The Engineer can easily update some framing sizes or preliminary reinforcement rates. These can then be imported back into the model
  • Involve the engineer in designing complex bespoke elements of the building in Rhinoceros and Grasshopper, these elements can be exported to space gas or strand for structural analysis. The principal is the same as using ETABS or Robot Analysis but the scope is limited to several smaller elements within the building. These bespoke elements can be exported to your building model as SAT. files.
  • Involve the Engineer in the Navisworks or Solibri clash detection process. The best person to decide if a beam penetration is advisable is a structural engineer.

CLASH

All these strategies are entirely voluntary, however it is worth noting that when your company signs up to the BIM execution plan you are making a commitment to providing a model that contains additional information to the construction drawings.  In Australia at least this means the Structural Engineer is legally bound to conduct a comprehensive model review at crucial points of the documentation process.  This is the unavoidable minimum requirement for all Engineers on Building Information Modelling projects.

The opinions expressed herein are my own personal opinions and do not represent my employer’s view in any way. Also – Anything that mentions AutoCAD, NAVISWORKS or REVIT or any other Autodesk product is a registered Trademark of Autodesk.

Links

Revit Structure to Robot Analysis

http://www.youtube.com/watch?v=4SXLJB8xKF0

Analysis in Revit Structure using Robot Analysis

http://www.youtube.com/watch?v=NtmU3fHBj24

Revit Structure to Robot Analysis

http://revitstructureblog.wordpress.com/2012/05/20/revit-structure-2013-to-robot-structural-analysis-professional-2013/

BrisBim

http://brisbim.com/

Rhinoceros 3D modelling software to Revit

http://rhinorevit.wordpress.com/

Understanding the MacLeamy Curve

http://www.cita.ie/images/assets/(holzer%202011%20ijarchcomp)%20bims%20seven%20deadly%20sins.pdf

BIM, Structural Engineering and the Digital Divide

Any conversation with a Structural Engineer about Building Information Modelling is an odd experience.  They will either tell you it is the best thing to happen to the industry in years, or that it simply doesn’t happen and doesn’t exist. The answer is either yes or no, black or white. Comments like “we tried it once and it doesn’t work” are not uncommon.

A conversation with an architect would be somewhat different. A lot of architecture firms have a BIM statement which locks them into steady progress, they may not be setting the world alight now but they plan to be in a few years. There are many one person firms doing a great job of documenting houses using 3D models with embedded data. The point is most firms have their toe in the water to some extent. To architects the question of BIM is a graded scale. They see themselves as all involved in some form of BIM, the only difference is the extent of that commitment

This ‘yes or no’ attitude of Structural Engineers is having a polarising effect on the industry. There are a group of large and medium-sized firms who dominate the BIM niche market. They share some of the characteristics listed below

AUTODESK 360

Characteristics of BIM capable Structural Engineering firms

  • A high percentage of government clients or large-scale projects
  • Transition to Revit® occurred pre-global financial crisis
  • The modelling occurs using multiple software platforms (for example Revit®, Tekla Structures and Navisworks®)  that are constantly changing
  • Highly skilled Employees
  • Low level of staff turnover
  • Often multi-disciplinary firms
  • Building modellers are engaged with architects and clients
  • Engineers and Modellers collaborate well
  • Building Modellers are perceived as adding value to projects
  • Fees and wages tend to be higher than average

The rest of the market seems to be headed in an entirely different direction.

Old drafting

Characteristics of Structural Engineering firms with no BIM capacity

  • Software tends to be several years old
  • The software that is used is not used to not used to its maximum capacity
  • Smaller commercial, residential and industrial projects
  • Higher staff turnover
  • Drafting is perceived as unskilled labour and a cost to be minimised
  • Minimal staff training
  • Lower than average fees and wages

While Building Information Modelling firms are no magical paradise, the trend is concerning. Would potential employees who had always worked outside the BIM community be able to get up to speed in less than two years? Would an engineer who had never used ETABS or Robot Analysis with Revit be able to step straight into a new project with minimal training?. The point is that the actual positions are so different, it is increasingly hard to move between the two worlds. There has been a 10 year conversation about legal issues, collaboration and level of detail, to name but a few issues, and it is difficult to enter that conversation and put those issues in context.

As the market slows down we can expect small to medium-sized consulting engineers to invest less in software, training and staff retention. Which leads to a vicious circle, the less you invest in these things, the less capable you are of landing a large project which could lead to increased profits, which could be invested in staff training and software.

Consulting engineering is a service industry. The best way to thrive long-term in such an industry is to provide the highest quality of service possible. Providing a low-cost, basic level of service may lead to short-term profits, but eventually those firms will lose out to the low-cost, basic service offered by offshore firms, who will always win any price war.

All is not lost for the ‘digital have-nots’. Firstly the current level of unemployment in the construction industry has seen many skilled engineers and modelling staff out of work. These people will eventually find employment with the digital ‘have-nots’, seeding their new ideas with their new employers. Secondly Australia must follow The United Kingdom’s and Singapore’s lead and pass Building Information Modelling legislation. Such laws (with a lengthy lead in time) would still deliver most of the pie to the BIM capable firms, but they would also deliver certainty to the industry and create a sense of urgency in the medium-sized firms that are in danger of being frozen out of a lucrative portion of the market.

http://www.out-law.com/en/articles/2012/december/uk-construction-sector-could-be-world-leader-on-building-information-modelling/

http://buildingsmart.org.au/nbi-folder/NationalBIMIniativeReport_6June2012.pdf

http://www.construction-innovation.info/images/pdfs/BIM_Guidelines_Book_191109_lores.pdf

http://www.aigroup.com.au/portal/binary/com.epicentric.contentmanagement.servlet.ContentDeliveryServlet/LIVE_CONTENT/Publications/Reports/2013/ACA%2520outlook%2520report%2520May%25202013%2520FINAL.pdf

http://www.abs.gov.au/ausstats/abs@.nsf/mf/8755.0

The views expressed in this blog are not necessarily those of my employer.