not only bridges

Why has Spain produced few famous scientists over the last centuries?

Spain has had a complex history that shaped the lack of a solid scientific environment over the past centuries.


First, Spain had a much harder Renaissance than France, England, or the Italian city-states. Spain spent a good portion of the Renaissance period engaged in a religious war to kick the Arabs out and expelling the Jews. Moorish Andalusia is where an important transfer of knowledge occurred. Everything associated with Moors and Ancient philosophy was considered heresy by the Inquisition and this probably made Spanish society more conservative. The Spanish inquisition truly dampened free inquiry and scientific exploration while France, England and the Italian city-states were creating the culture that nurtured most of the later famous scientists.

Then, the strongest resistance to progress and modernisation was probably expressed in the antagonism between the Francophiles and their opponents. Francophiles were accused of all sorts of religious heterodoxy. The 2nd May is a absurd public holiday in Madrid that celebrates the rebellion by the people of Madrid against the occupation by French troops. In reality, the 2nd May was a disaster day beacause of the following counter-revolution and reactionary policies. The people, blaming the policies of the Francophiles for causing the Napoleonic occupation by allying Spain too closely to France, at first welcomed Ferdinand VII. Under his rule, liberal schools and libraries were closed down, the engineering school was closed down, part of the press was suppressed and many editors and many writers were imprisoned. Even the liberal members of the Catholic church became victims of prosecution and the most scientifically educated group -the Jesuits- were expelled from Spain in mid XVIII.

And, last but no less significant, the Spanish civil war and the subsequent ideological conservatism of the dictatorship were a total tragedy for Spanish science. A whole generation of promising scientists was exiled.

A hundred or so common used acronyms in oil and gas engineering

One of the first things that shocked me when I started to work for the oil and gas (O&G) sector is that many acronyms and abbreviations are used. It gave me a hard work for a few weeks to get used to the language. Most of them are three letter acronyms (TLA). The list below is not anywhere near exhaustive or definitive and it is meant for indicative purposes only.

  • AACQ = Actual Annual Contract Quantity
  • AASHTO = American Association of State Highway and Transportation Officials
  • AB =  Anchor Bolt
  • ABB = Activity Based Budgeting
  • ABC = Activity Based Costs
  • ABM = Activity Based Management
  • ACHE = Air-Cooled Heat Exchanger
  • ACI =  American Concrete Institute 
  • AE = Architecture and Engineering
  • AISC = American Institute of Steel Construction 
  • AP = Accounts Payable
  • AR = Accounts Receivable
  • ASCE = American Society of Civil Engineers
  • ASCII = American Standards Code for Information Interchange
  • ASME = American Society of Mechanical Engineers
  • ASTM = American Society for Testing and Materials
  • AVL = Approved Vendor List
  • AWS = American Welding Society 
  • BH = Beam Height
  • BIC = Best In Class
  • BIM = Building Information System
  • BOG = Boil-off Gas
  • BOM = Bill Of Materials
  • BOP = Bottom of Pipe
  • BOQ = Bill Of Quantities
  • BOS = Bottom of Steel (beam)
  • BTU = British Thermal Unit 
  • CEN = Comité Européen de Normalisation
  • CFD = Computational Fluid Dynamics
  • CHF = Critical Heat Flux
  • DIN = Deutsches Institut für Normung (German Institute for Standards)
  • EEMUA = Engineering Equipment & Materials Users’ Association
  • EOR = Enhanced Oil Recovery
  • EPC = Engineering Procurement and Construction
  • ERP = Enterprise Resource Planning
  • FEA = Finite Element Analysis
  • FEED = Front End Engineering and Design
  • FEM = Finite Element Method
  • FHWA = Federal Highway Administration
  • FOB = Free On Board
  • FPSO = Floating Production Storage and Offloading
  • FSRU = Floating Storage and Regasification Unit
  • GAAP = Generally Accepted Accounting Principles
  • GEP = Good Engineering Practice 
  • GL = Ground Level
  • GMROI = Gross Margin Return on Investment
  • GOSP = Gas Oil Separation Plant 
  • GTL = Gas-to-liquids conversion
  • HAZID = Hazard Identification
  • HAZOP = Hazardous Operations
  • HE = Heat Exchanger
  • HGO = Heavy Gas Oil
  • HSE = Health Safety and Environment
  • HSV = Hookup Support Vessel
  • HVAC = Heating Ventilation and Air Conditioning 
  • I/O = Input Output
  • IABSE = International Association for Bridge and Structural Engineering
  • IDC = Interdisciplinary Comment
  • IEEE = Institute of Electrical and Electronics Engineers 
  • IFA = Issued For Approval
  • IFC = Issued For Construction
  • IFD = Issued For Design
  • IFR = Issued For Review
  • IPD = Integrated Project Delivery
  • ISO = International Standards Organization
  • ITB = Instructions To Bidders
  • JIT = Just In Time
  • KPI = Key Performance Indicator
  • LCC = Life-Cycle Cost 
  • LNG = Liquid Natural Gas
  • LPG = Liquid Propane Gas / Liquified Petroleum Gas
  • LPH = Littres per hour
  • LPSV = Low Pressure Safety Valve
  • LVPSV = Low and Vacuum Pressure Safety Valve
  • MAWP = Maximum Allowable Working Pressure
  • MBR - Minimum Bend Radius
  • MOL = Maximum Operating Level
  • MRO = Maintenance, Reparation and Overhaul (también como revamping)
  • MSL = Mean Sea Level
  • MTO = Made To Order
  • MTO = Material Take-Off
  • MTS = Make to Stock
  • NB = "Nota Bene",  Latin phrase for "Special Note" 
  • NDA = Non Disclosure Agreement
  • NDE = Non Destructive Examination
  • NFPA = National Fire Protection Association 
  • NIC = Not In Contract 
  • NPD = Nominal Pipe Diameter
  • NPS = Nominal Pipe Size
  • NPSH =  Net Positive Suction Head
  • NRI = Net Revenue Interest
  • NRV = Non Return Valve
  • NTS = Not To Scale
  • OBE = Operating Basis Earthquake
  • OD = Outside Diameter
  • OEM = Original Equipment Manufacturer
  • P&ID = Process and Instruments Diagram (sometimes as PID)
  • PLEM = Pipeline End Manifold
  • PPA = Project Plan of Activities
  • PSD = Process Shutdown
  • PSS = Platform Safety System
  • PSV =Pressure Safety Valve (Equivalent to PRV or automatic Pressure Relief Valve)
  • PV = Pressure Vessel
  • RFP = Request For Purchase
  • RFQ = Request For Quotation
  • RW = Rainwater
  • SIL = Safety Integrity Level
  • SQ = Site Query
  • SSE = Safe Shutdown Earthquake
  • SSL = Structural Slab Level
  • STIG = Steam Injected Gas Turbine 
  • TCP = Top of Corner Protection
  • TL = Tangent Line
  • TOC = Top of Concrete
  • TOC = Total Owning Cost 
  • TOS = Top of Steel
  • TQ = Technical Query
  • TSD = Technical Support Document 
  • UNO = Unless Noted Otherwise
  • VPSV = Vacuum Pressure Safety Valve
  • WP = Waterproof.
Other useful references:

How can civil engineers improve the sustainability of buildings?

There are some simple tips that can help improve the sustainability of our building solutions.

First of all, go for structures that are durable and avoid premature obsolescence. The most sustainable thing we can do is to provide structures that will be used for decades with simple and affordable maintenance. Replacing structures is expensive, so it is worthwhile finding out if their service life could be extended. Consider the enlargement, demolition and reuse of your structures. Good engineering consulting is to keep others -colleagues or clients- informed about more than the initial costs.

Then, civil engineers need to select the appropriate material which will not produce much harm to the environment, this is, using eco-friendly materials for the building. There’s a thin line between sustainability and locality. Sometimes the first step to sustainability is to choose materials which are locally found and widely used in the location. Consider minimizing the construction waste, noise and pollution on site. Also, try to understand the strengths of the local manpower and the traditional construction knowledge. Bear in mind that one size does not fit all and do your best to avoid the gross errors of the international style modernist movement.


Finally, adopt sustainable practices in your personal life and read about sustainability as much as you can. Craddle to craddle is a good book to start and get inspired. Whether our green proposals are accepted or not, we always have a chance to make a difference leading by example.

Photo: Bilbao Arena Miribilla, ACXT-Idom

Preferred geometry file for FEA: IGES, STEP or SAT?

IGES and STEP are the widely used neutral CAD formats and accepted in nearly all software packages.

IGES or IGS (Initial Graphics Exchange Specification) is the first CAD data exchange standard developed and it is capable of exchanging only geometry and topology information between different CAD systems.

STEP or STP (STandard for the Exchange of Product Data) enables storing, retrieving, sharing and archiving member data (f.ex. profie sections, material properties, etc...) throughout its life-cycle among different databases and STEP has become the industry standard for Data Exchange.

For Finite Element Analysis (FEA), preference for one or the other depends upon several things including:
1) the source CAD that is used to create the neutral format.
2) the target CAD, CAE or FEA package and the use for which the file is intended.
3) the kind and complexity of geometric elements included in the design (e.g., prismatic elements, splines, surfaces, etc.)

In IGES the output is in lines and surfaces while STEP file keeps the assembly hierarchy and output is a mixture of solids,volumes and surfaces. For FEA purposes IGES may be enough as you don't usually need solids/volumes. IGES works ok for importing beams and sometimes works well for plates.
For those that work in the 3D solid modelling world, STEP format may be preferred as it retains the solid geometry and brings the part into the 3D modelling software in solid format. In general STEP is also more robust than IGES for plates and shells imports.

ACIS SAT is very similar to STEP. The kernel of many AutoDesk and Dassault products is partially based on ACIS. For example Abaqus uses ASICS (*.SAT) as it's native kernel so I usually start there and then go to STEP and IGES would be the last choice.

Stupid as it may sound, I generally request more than one format and a screenshot image of what it should look like.

How do I validate FEA results?

First of all, check the numerical consistency of the results:

- Ensure convergence of solution: refine mesh and check if changes in the answer are smaller and smaller.
- As an error estimation look at strain jumps between adjacent elements with results not averaged or smoothed.

Then, compare to other theoretical/numerical results if available. Compare to empirical results if available. For hand-made engineering calculations I recommend MathCAD (or Smath Studio) instead of Excel because the formulas are readeable and with named variables.

Last but not least, compare with systems of increased complexity. For example, if you are analyzing 3D dynamic system with nonlinear material, start with 2D linear static and build confidence in your solutions by adding complexity step by step.