Papers and presentations from IALCCE 2018

Last fall, I attended IALCCE 2018 where together with my colleagues from TU Delft, I organized a Mini Symposium on Load Testing of New and Existing Structures.

For this MS, I submitted 4 papers as coauthor - 3 of these papers are the results of projects with B.Sc. thesis students from USFQ funded by my 2016 Chancellor Grant. During the MS, I presented my work on stop criteria and I also presented about diagnostic load testing of steel bridges on behalf of ADSTREN.

The abstracts of the papers are:
Proposed stop criteria for proof load testing of concrete bridges and verification
Eva Lantsoght, Cor van der Veen, Dick Hordijk
In a proof load test, a load representative of the factored live load is applied to the bridge. Since the applied load is large, stop criteria are important. Stop criteria for shear and flexure are proposed based on existing codes and guidelines, laboratory experiments, and theoretical considerations. This proposal is verified with the results from pilot proof load tests. The result of this comparison is that the stop criteria are never exceeded, or that they are exceeded only in the last load step. The proposed stop criteria are thus not overly conservative for application to field testing. However, information about the available margin of safety is not always available, especially for shear failures, and will need further experimental validation.

Nonlinear finite element analysis of beam experiments for stop criteria
Jose Eduardo Paredes, Eva Lantsoght
Proof load testing is used to assess the structural capacity of existing bridges. Stop criteria, based on measurements taken during proof load tests, determine if a test should be stopped before reaching the target proof load in order to maintain structural integrity. A nonlinear finite element model is proposed to investigate stop criteria. A reinforced concrete beam with plain reinforcement is modeled. The goal is to develop a reliable finite element model with adequate material constitutive models to analyze available stop criteria from existing codes. The beam experiment is verified in terms of strains. Stop criteria from ACI 437.2M-13 and the German guideline are analyzed for the beam model. The presented analysis shows that nonlinear finite element models can be used for the evaluation of stop criteria for proof load testing to limit the required number of laboratory tests.

Development of a stop criterion for load tests based on the critical shear displacement theory
Kevin Benitez, Eva Lantsoght, Yuguang Yang
The capacity of existing bridges is an important aspect regarding the safety of the traveling public.
Proof load testing can be a useful option to evaluate if an existing bridge satisfies the requirements from the code. The stop criteria provided by the Guidelines are generally suitable for flexure only. Therefore, in this paper, shear is considered. When developing a stop criterion for shear for proof load tests on existing bridges, many different approaches could be taken. Here, a stop criterion is developed based on the Critical Shear Displacement Theory. The development of the stop criterion is based on the analysis of the contribution of each of the mechanisms of shear transfer. The criterion is verified with experiments on beams in the laboratory. The consequence of this development is that now a stop criterion for shear with a theoretical basis is provided.

Verification of flexural stop criteria for proof load tests on concrete bridges based on beam experiments
Andres Rodriguez, Eva Lantsoght
When performing proof load tests, irreversible damage may occur. Guidelines for performing the test have been developed, which establish stop criteria to terminate the test before this happens. The stop criteria prescribed in the currently available codes are mainly designed for buildings, but load tests are also performed on bridges. This investigation compares the results from beams tested in the laboratory with stop criteria and analyzes their applicability on reinforced concrete bridges. The stop criteria from ACI 437.2M-13, the German guideline of the DAfStB, and a proposal developed by Werner Vos from TU Delft were evaluated. It was found that the DAfStB concrete strain stop criterion provided the most consistent results. The ACI stop criteria should only be applied if the ACI loading protocol is being followed. The deflection proposal by Vos, seems to be a reliable option, but further investigation needs to be done before it can be applied.

The slides of the presentations are:

Proposed stop criteria for proof load testing of concrete bridges and verification from Eva Lantsoght

Diagnostic load testing of bridges - case studies from Eva Lantsoght

The carbon footprint of academic conference travel

The latest IPCC report on climate change worries me deeply - I can't ignore the alarm bells this international panel of scientists have set off. Generally, I try to be make environmentally friendly choices: I eat plants, I walk my commute, I buy second hand clothes and furniture as much as possible, my kid is in cloth diapers, I recycle as much as possible etc etc. But the elephant in the room for my lifestyle is my traveling. I used to get excited about the opportunity of going to a conference halfway around the world. Now, I worry about the carbon footprint of my trip.

So I ran a poll on Twitter to see if I'm the only one - and I learned we as academics have heard the alarm set off by our fellow scientists. Now let's go one step further and take direct action in our teaching and our profession (how? I am still trying to figure that out!). Here's the poll and its wake:

Two papers on the arched strut

In 2018, I was co-author of two papers on the topic of the arched strut - both were presented by my colleague Dr. Alexander.

The first paper, presented at the conference on Short and Medium Span Bridges in Quebec City, looks at the use of the arched strut for approach slabs of bridges and considers the effect of fatigue. The abstract is as follows:

Strut-and-tie models (STM) are appropriate for analyzing and designing disturbed regions in a reinforced concrete structure. The arched strut is an addition to the STM tool kit. It models the combination of disturbed behavior in one direction with slender behavior in the perpendicular direction. The arched strut is part of the Strip Model, originally developed to model load transfer between a two-way slab and its supporting column.
It is difficult to define the geometry of conventional STM in a slab. One end of the strut is connected to the concentrated load but there is no similar feature to define the position of the other end. The arched strut is a means of addressing this difficulty. The method does not model a failure criterion; rather, it defines an acceptable load path that meets static and material constraints.
This paper summarizes the technique in the context of column-slab connections, develops the modifications needed to model conventional punching of an approach slab under a patch load, and proposes additional modifications to adapt the analysis to fatigue loading.
The principal findings are that, while the analysis for two-way shear given in S6-14 are deficient, the punching strength of a typical approach slab under both static and fatigue loading from a CL-W truck should not be a concern.


The second paper, presented at IABSE Nantes in September 2018, describes the arched strut from a more general perspective and shows how the arched strut can be used as a tool in the strut-and-tie models toolkit. The abstract is as follows:

The arched strut is an addition to the strut-and-tie (STM) tool kit. It models the combination of disturbed behavior in one direction with slender behavior in the perpendicular direction. Common applications for the arched strut are in the design of connections between a reinforced concrete slab and its supporting columns or punching of bridge decks.
The arched strut can be applied to any combination of shear and moment at a column-slab connection. The designer is given clear guidance on anchorage requirements for the flexural reinforcement and the expected ductility of the connection. The method does not model a particular failure criterion; rather, it defines an acceptable load path that meets design objectives.
The paper outlines the basis for the arched strut and presents examples illustrating its use in design.

Two papers from IABMAS 2018

My colleagues and I have published two papers in IABMAS 2018. I was supposed to travel to Melbourne to present these papers, but it was very shortly after my return from my annual research stay in Delft, and my baby girl did not take well to my absence and return, so I was adviced to invest time in restoring our bond. I was warned against not traveling after such a short time again, as it may leave her confused. So I canceled the conference (only second time ever I had to cancel a conference, and I did feel bad about it, but I also felt bad about my baby not being well because of my long absence...).

The two papers we published were part of a Special Session that we organized at the conference (it's a pity I couldn't travel and chair the session I spent so much time preparing on, but such is life...).

The first paper is "Monitoring crack width and strain during proof load testing" and the abstract is:
In a proof load test, the applied load is representative of the factored live load, to demonstrate experimentally that the bridge fulfils the code requirements. Signs of distress must be caught with the instrumentation by defining stop criteria. In the literature, several stop criteria for flexure are available. The German guidelines describe, amongst others, a limiting crack width and strain. However, the background of these limiting values is not clear. Therefore, a theoretical approach based on flexural theory is followed. The theoretically derived values are then compared to experimental results obtained from beam experiments. The result of this research work is a limiting value of crack widths and strains that can be used during proof load testing of concrete bridges. The arbitrary stop criteria that were used in the past can now be replaced by stop criteria that are based on the theory of concrete beams in flexure.

The second paper is "Twenty years monitoring of a high strength concrete cantilever bridge" and the abstract is:
In 1997 the Second Stichtse Bridge, a high strength concrete box girder bridge was built in the Netherlands using the balanced cantilever method. At that time, the long-term behaviour of this material (with a cube compressive strength of 75 MPa) was not known. Therefore, it was proposed to monitor the material behaviour and the deflections of the bridge for ten years, and a few properties have been monitored for twenty years. To evaluate the concrete material properties over time, concrete cubes were cast with the segments, and stored inside the bridge at the section locations. These samples have been tested periodically. Also shrinkage measurements were carried out on a concrete sample stored inside the bridge. The deflections of the bridge superstructure have been measured periodically along both edges of the bridge. Based on the available data, it is found that the concrete compressive and splitting tensile strength, as well as the shrinkage deformations, remain constant. The deflections are stabilizing as well.

Conference dress codes

Do you always wonder about the clothes you should pack for a conference? The fact is, in academia, the dress code for conferences is less defines than in some other fields of work. I already wrote a post in the past about my essential conference clothes, but my view is quite limited by my field.

To get a better understanding of conference dress codes, I ran a poll on Twitter. You can find the wake of this poll below:

Beam experiments to investigate loading protocol and stop criteria for load testing

I recently presented a poster about our research on load testing in Delft at the ACI Spring Convention in Detroit, MI.

Poster presentations are not something I'm quite used to. I've written about my experience presenting a poster for the first time (in 2012), and since presenting that poster, I've only given lectern sessions. Besides that, I've made two posters for the research school of building and construction of the Netherlands, for their book of research projects, way back in 2009 and 2010.

The poster sessions was well attended, and I enjoyed the direction interaction with the audience. As such, I'd vote in favor of adding more poster presentations to the conferences in my field (as long as we can consider them as equal to lectern sessions, instead of considering them as a little "less" valuable).

You can find the poster here (you can scroll through it):

Beam experiments to investigate loading protocol and stop criteria for load testing from Eva Lantsoght

Determination of loading protocol and stop criteria for proof loading with beam tests

At the fib symposium 2017, I presented a paper titled "Determination of loading protocol and stop criteria for proof loading with beam tests". The abstract of the paper is as follows:

Proof loading of existing bridges is an interesting option when insufficient information about a bridge is available. To safely carry out a proof loading test, high loads are placed on the bridge. To avoid permanent damage to the structure, a controlled loading protocol needs to be described, and the measurements need to be closely monitored to identify the onset of distress. The criteria from existing codes and guidelines to evaluate the measurements, called stop criteria, are not universally applicable. To develop recommendations for proof loading of reinforced concrete solid slab bridges, beam experiments were analysed. The beams were heavily instrumented to evaluate the existing stop criteria, and possibly develop new stop criteria. The result of these experiments is the development of a standard loading protocol for the proof loading of reinforced concrete slab bridges. Recommendations for the use of the stop criteria are also formulated. These insights are used to develop a new guideline for the proof loading of reinforced concrete slab bridges in the Netherlands.

Here you can find the slides of the presentation:

Determination of loading protocol and stop criteria for proof loading with beam tests from Eva Lantsoght

Extended Strip Model for slabs subjected to a combination of loads

I recently presented a paper titled "Extended Strip Model for slabs subjected to a combination of loads " at the fib symposium in Maastricht.

The abstract of the paper is:

Reinforced concrete slab bridges are assessed for a combination of loads that include self-weight, superimposed loads, and distributed and concentrated live loads. The shear capacity of reinforced concrete slabs subjected to a combination of loads is thus an important topic for the assessment of existing bridges. Currently, a plastic model exists for the assessment of reinforced concrete solid slabs subjected to a concentrated load: the Extended Strip Model, based on the Strip Model for concentric punching shear. To apply this model to slabs subjected to a combination of loads, the model needs to be adapted based on theoretical principles. The results are then compared with the results from experiments on half-scale slab bridges subjected to a combination of a concentrated load close to the support and a line load. The result of this comparison is that the proposed method is suitable to find a safe estimate of the maximum concentrated load on the slab. The implication of this development is that an improved tool is available to estimate the maximum load of a truck that can be placed on a reinforced concrete bridge, thus improving the current assessment.

Here you can find the slides of the presentation:

Extended Strip Model for slabs subjected to a combination of loads from Eva Lantsoght

PhD Talk for AcademicTransfer: How to select which conference to attend

This post is part of the series PhD Talk for AcademicTransfer: posts written for the Dutch academic career network AcademicTransfer, your go-to resource for all research positions in the Netherlands.

These posts are sponsored by AcademicTransfer, and tailored to those of you interested in pursuing a research position in the Netherlands.

If these posts raise your interest in working as a researcher in the Netherlands, even better - and feel free to fire away any questions you might have on this topic!

When you start your PhD, outline where (at which conferences) you would like to present your work. Don’t wait until you feel “ready” to present something – it is not uncommon for conferences to require abstract submission 1.5 years before the actual conference. Talk to your fellow PhD students to learn where your supervisor usually takes his/her students, and talk with your supervisor about wanting to present your work at conferences as early as possible. Certainly, your plans can change as you move through your PhD, but have an idea of where you would want to present early on, and work towards the realization of that plan.

Ideally, you have been able to discuss travel funding prior to taking your PhD position, but if you are unsure about what to expect, then bring the topic up as soon as possible. The funding of the project you are working on is crucial here: it could allow you to present at a number of conferences each year, or it could limit you to one single conference per year. If your funding does not include a travel budget, look for other options. Many universities and professional associations provide scholarships for students to travel to conferences. You can also consider participating in student competitions, essay contents, and other competitions which can award you with travel funding.

Now that you know that there are many ways to find funding to travel to conferences, and that you should start building your conference wishlist early on, let’s focus on selecting the right conference. There are different types of conferences:

• Meetings of international associations: The largest conferences tend to be the meetings of international associations. These associations can meet annually, or less frequently. A good place to start looking for information would be on the websites of international associations that you are involved with or that are important in your field. If you are not a member of any international association, start looking for the important players in your field. A good starting point would be the associations that publish the journals you read, for those journals that are not owned by large publishing houses. Keep in mind that many international associations offer free or very cheap student memberships. Once you’ve identified the important international associations, look on their websites for information about their events. Many international associations also mention events they cosponsor, so you can be informed about meetings you would not hear about otherwise.
• National meetings: If you want to test the waters before you take your research abroad, and keep your travel costs lower, looking into national meetings is a good starting point. While not all national meetings require you to write a conference paper, presenting your work to a smaller audience and perhaps in your native language may be a more comfortable first step. These national meetings can be organized by national member groups of the international associations that you follow. Another type of events is organized by research groups of universities that study the same topic, giving PhD students an opportunity to share their research with researchers in the same field. Sometimes, young member groups of international organizations or student chapters of international organizations organize events in which you may want to present your research.
• Industry events: There’s a whole array of different industry events that can be particularly interesting towards the end of your PhD trajectory, when you may want to explore opportunities outside academia. Some industry events are gatherings of academics and practitioners in a certain branch of the industry. These events typically have lectern sessions, in which you could present your work. Inquire if there is a possibility, but keep in mind that in some fields these lectures feature senior professors who give a more general overview of the current state of the art. Other industry events are career fairs, and trade shows, which you may want to attend to learn about your opportunities after your graduation, but which do not offer you the ability to present your work.
• Specialized workshops: Workshops on specialized topics can be organized by international associations, or on the initiative of a few senior professors. Whereas these events typically tend to gather a small but focused group of researchers, it is more difficult for you during your PhD to learn about these events. Sometimes, these events are announced on the website of the overbearing international association. The presentations can be by invitation only, but if you are interested in participating and presenting your work, talk to your supervisor and see if he/she can get you a spot in the workshop.

Most information about upcoming conferences can be found online, and the internet (including the websites of the most important international associations) can provide you with a great amount of information. Sign up for newsletters of international associations to stay informed about the events they organize or co-sponsor. Tell your fellow PhD students and supervisor that you are looking for information about interesting conferences; they will forward you calls for abstracts when something interesting for you comes up. Ask your fellow PhD students and supervisor to bring flyers announcing future conferences when they travel to conferences.

Before finishing this topic, I need to give you a word of caution. If you receive an email with an invitation to submit an abstract for a conference, and it looks interesting, make sure you check if the conference is legit. Check their website, and see if the event is endorsed by any international association that you know. Check the organizing committee and scientific committee, and see if there are reputable scientists involved. If you are doubting whether the conference is legit, write one of the members of the scientific committee to ask about the scope of the conference. Some predatory conferences unfortunately just slap some names on a website without asking these scholars for permission. You wouldn’t expect it, but some companies have decided to make easy money with the organization of “academic” conferences: they ask high registration fees, and use no academic rigor in the peer review process (or use no peer review whatsoever) to organize conferences with the sole objective of making some quick money. Red flags for these predatory conferences are: poor English in the email, a promise for fast publication or publication in a journal, or you being invited as plenary speaker or session chair (by someone you don’t know at all). If you are doubting whether a call for abstracts is legit, google the name of the conference with “bogus conference”, “fake conference”, “predatory conference” or “scam conference” added to it to see if others have been fooled by the same organization.

How many conferences do academics attend per year?

I recently ran a poll about the number of conferences academics attend, and the results are in: the vast majority travel to 1 - 4 conferences per year.

I tend to attend a bit more than 4 conferences per year, because there are a number of conferences that I don't like skipping - but my conference travel schedule tends to be packed and exhausting. And as a new mom, it's time to reconsider and evaluate where my priorities lie.

Over the past years, I've attended these conferences:

• ACI Conventions: twice per year, always in North America - and I don't like to skip these because I serve on committees that meet at these conventions.
• TRB Annual meeting: every January, in DC - which I don't like to skip because of the committee meetings
• IABSE - holds symposium once per year and a conference once per year. I attend every now and then.
• IABMAS - holds a conference every other year, which I try to attend every time.
• IALCCE - holds a conference every other year, which I try to attend.
• fib - holds a symposium every year, which I try to attend.
• ESREL - Safety and reliability are not my main research topics, so I've been sending in papers only a few times.
• ICCRRR - these conferences are only every 3 years.
• Euro-C - only once every 4 years, and usually my co-author/colleague goes there
• ASCE Structures Congress - once a year in the USA, but I've only gone once
• Stuctural Faults and Repair - every other year. I've gone once; the other years their dates coincided with IABMAS.

Proof load testing in the Netherlands - overview of current research

At the ACI Spring Convention in Detroit, MI, I gave a presentation in the committee meeting of ACI 437. In this presentation, I gave a quick overview of the research we've been doing in the Netherlands related to load testing.

You can find the slides of this presentation below:

Proof load testing in the Netherlands - overview of current research from Eva Lantsoght

Defining loading criteria for proof loading of existing reinforced concrete bridges

Recently, at the fib symposium 2016 in Cape Town, I presented a paper that I co-authored with a junior colleague, who wrote his first paper. Here is the abstract of the paper:

As the bridge stock in The Netherlands and Europe is ageing, various methods to analyse existing bridges are being studied. Proof loading of bridges is an option to study the capacity when crucial information about the structure is lacking. This information could be related to the material (for example, the effect of alkali-silica reaction on the structural capacity) as well as to the structural system (for example, the effect of restraints at the supports or transverse redistribution capacity). When it is decided to proof load a bridge, the question arises which maximum load should be attained during the experiment to approve the capacity of the bridge, and which criteria, based on the measurements during the test, would indicate that the proof loading needs to be aborted before reaching the maximum desired load (the so-called stop criteria). To define the required loading criteria, a review of the literature has been made, finite element models of existing viaducts have been made, and on these viaducts, proof loading tests have been carried out. These bridges were heavily instrumented, with a goal of learning as much as possible about the structural behaviour during proof loading. As a result of the analysis and experiments, recommendations are given for proof loading of bridges with respect to the required maximum load and the stop criteria.
These recommendations are important, since they form the basis of a guideline for proof loading of existing concrete bridges that is under development in The Netherlands.

Please find below my slides of the presentation:

Defining loading criteria for proof loading from Eva Lantsoght

Shear Capacity of the Ruytenschildt Bridge

I recently presented a paper at the 2016 fib symposium in Cape Town on the shear capacity of the Ruytenschildt Bridge. The abstract of the paper is as follows:

In August 2014, the Ruytenschildt Bridge, a reinforced concrete solid slab bridge (reinforced with plain bars) in the Friesland province in the Netherlands was tested until failure. One of the goals of proof loading and testing this bridge to failure, was to study the failure mode of existing slab bridges. The combination of smaller shear capacities as prescribed by the Eurocode in combination with the heavier live load models, has raised concerns with regard to a number of existing slab bridges in the Netherlands. As the shear capacity of existing bridges is under study, the results of testing an actual slab bridge until failure are used to compare to the results of testing half-scale slab specimens in the laboratory, and the conclusions resulting from those experiments. In this paper, the results of the predictions based on the first order of approximation rating procedure from the Netherlands for shear, the Quick Scan method, as well as based on predictions of the failure mode and the average predicted capacity are compared to the experimental results. The predictions show a possibility of shear failure in the second span of the bridge. The experiment showed that both spans of the bridge failed in flexure. The observed failure mode is important, as some of the results indicate that the solid slab bridges, currently under discussion with regard to their shear capacity, fail in flexure in reality. Flexural failure is considered a ductile failure compared to the brittle failure mode in case of a shear failure.


Please find below the slides of my presentation:

Shear capacity of the ruytenschildt bridge from Eva Lantsoght

Improved formulation for compressive fatigue strength of concrete

I recently traveled to Leipzig, Germany to present a paper at the 4th International Conference on Concrete Repair, Rehabilitation and Retrofitting. The research I presented was the result of the project I worked on during Summer 2014 in Delft, where we had a small research project to come up with an improved formulation for concrete under fatigue for the Dutch National Annex to Eurocode 2-2.

The abstract of the paper is as follows:

Understanding the behavior of concrete in fatigue is essential for understanding the behavior of concrete bridges subjected to repeated loads. The Dutch National Annex to the Eurocode prescribes a different expression for the Wöhler curve for compression fatigue than the Eurocode itself, and does not have a smooth transition for 106 load cycles. A new expression for concrete in compression fatigue is thus necessary. This new expression should be valid, yet not overly conservative, for high strength concrete. Therefore, a database of experiments on (ultra) high strength concrete tested in compressive fatigue is used to validate the new proposal. A proposal for the assessment of the fatigue strength of existing structures is prepared. For design, a simplified method is proposed. An expression for the fatigue strength of concrete under compression, suitable for high strength concrete, is now available, which can replace the previous fatigue expressions used in The Netherlands.

The presentation I gave is shown here:

Improved formulation for compressive fatigue strength of concrete from Eva Lantsoght

PhD Talk for AcademicTransfer: How to prepare for your first conference

This post is part of the series PhD Talk for AcademicTransfer: posts written for the Dutch academic career network AcademicTransfer, your go-to resource for all research positions in the Netherlands.

These posts are sponsored by AcademicTransfer, and tailored to those of you interested in pursuing a research position in the Netherlands.

If these posts raise your interest in working as a researcher in the Netherlands, even better - and feel free to fire away any questions you might have on this topic!

Today's post is about preparing yourself to attend and (I am assuming) to present at your first academic conference. I'm assuming you have written your paper (if you haven't done so yet, check out how I write my conclusions), and your request has been approved - now, all that remains to be done, is to "just" go and attend the conference.

1. Request a travel budget

I think it's inherently wrong that we're so often tacitly assumed to be forking out (part of) the money ourselves to attend conferences. Asking an underpaid PhD student to pay a registration fee of 1000 USD at a conference is so far away from the gist of why we are practicing science and want to exchange our ideas. Most universities do have travel budgets you can apply to. Some of these additional scholarships are more unbiased, in other cases you might just need to write a letter to an Important Person and hope he reads this on a good day and helps you with the expenses. By all means, the system at Delft University of Technology is fair and straightforward: if you have the approval to travel, they take care of all your expenses (including the cost of food while you are away).

2. Book in advance

Many conferences have early-bird registration fees. Avoid additional costs by booking as early as possible (by the same token: apply for travel funding as early as possible). Similarly, your flight ticket and hotel registration may be cheaper when you book in advance - and you avoid the unpleasant situation of not finding spots on the flight or in the hotel of your choice anymore as the date of your conference approaches. Booking early is part of being well-prepared.

3. Study the conference schedule

Now that you know that you are going for sure, it is time to outline your itinerary for the days of the conference. Make sure you read all the information of the conference, and know where and when to register (pro tip: try to register as early as possible to avoid unpleasant surprises, such as a payment that did not go through and your registration that did not get processed).
Read the titles of all presentations to familiarize yourself with the topics, and mark which presentations you want to see. Note that sometimes presentations only are remotely related to the topic of the session, so don't let yourself be guided too much by the topic of the session. Plan to ask questions after the presentations as well.

4. Identify who to talk to

From the conference schedule, identify who is carrying out research related to yours, and make sure you attend these presentations. Try to talk with the presenter after his/her presentation, so you can introduce yourself to him/her. Also identify in the scientific committee if there are senior researchers you would like to talk to - often the members of the scientific committee will attend the conference as well.

5. Plan some downtime

Conferences are exhausting, so it is a good ideas, especially for your first conference, to identify when you could have a little bit of downtime. If your conference schedule is packed with dinners until midnight and sessions that start at 8 am, you will be running on -say- 6 hours of sleep, which for many of us is not enough. Factor in the fact that attending conference presentations is like a scaled-up version of attending lectures, and you know you need your full concentration to benefit from attending the sessions. Often as well, you will be jetlagged and tired from traveling to the conference, so that doesn't help either to keep your attention sharp. Don't neglect self-care when traveling.

6. Pack your clothes

When packing your bag, travel light - just take the clothes you are planning to wear for the days of the conference, a spare shirt in case you spill your coffee, workout clothes if you think you can squeeze in some exercise, and comfortable clothes for your flight. You can find an overview of what I typically take to a conference here. Keep in mind as well that sometimes you might be traveling to a warm destination, but the AC in the conference venue might be turned to arctic. Similarly, you might be heading to Snow Capital in January, and find that the heating is set to boil you alive. The solution: take some layers.

7. Explore the city

Plan in advance when you will have time to see something of the city, and what you are going to visit. Keep in mind that the conference is your main goal, but that the chance that you will return to the city of the conference in the next years might be small. A good strategy is to arrive early: you will have a day to see something of the city, register for the conference, and if your flight gets delayed you only miss out on the touristing part and will not have your attendance at the conference in peril.

8. Go with your presentation ready

You will not have time to make your presentation during the conference. Go well-prepared and have your presentation ready, and practiced. I typically make my presentation 2-3 weeks in advance so that I can send it to my co-authors for approval. I also (still, after all these years!) practice my presentation until I have a good feeling for the time I have available. Keep in mind as well that if, for example, your conference has 4 presentations per hour, you will not speak for 15 minutes. You'll need to calculate the time for getting introduced, sometimes the time for getting the computers up and running, and time for questions. For this case, prepare a presentation of 10-12 minutes. You don't want to be the person taking too much time (especially not before the coffee or lunch breaks, when everybody wants to go eat, drink something or just take a break). Many conferences will ask you to send/upload your presentation in advance. By all means, check in the speaker ready room if your presentation is in the system, and if everything comes on the screen as you intended it to (different versions of powerpoint sometimes move things around - correct that before you are up on the stage to present).
If you feel insecure about presenting your (early) work to some of the top researchers in your field, you can practice power-posing to boost your self-confidence.


9. Travel early

I once almost missed the first day of a conference because my first flight was delayed, I missed my connecting flight and then was put onto the waiting list. I was hoping so hard they'd find a spot for me, and just before the flight took off, I heard my name from the standby list as cleared to board. Since then, I've been traveling with a day of extra time for my long flights. I'd rather stay one night extra in the hotel, than miss the entire first day of a conference because of travel problems.

10. Have everything backed-up

Print out your boarding pass, hotel reservations and conference registration confirmation. Figure out how to get from the airport to the hotel to avoid having to pay for a cab. Print out your slides of the presentation to practice. Put all the emails about the conference, your paper, presentation and all relevant documents on a back-up for when you need them. I am not traveling with a laptop anymore, but use a Surface tablet (the device itself is so glitchy that I wouldn't recommend you getting it, but when it works, it is useful for my teaching and for having access to MS Office and the internet when traveling)

11. Plan you time before and after the conference

I once did the math to see how much time a conference really takes me - from the step of finding a suitable conference to present my work to the point of needing some extra time to recover after a conference.
Keep in mind as well that, after the conference, you don't just simply return to your office, park yourself in front of your computer and get going again. You'll need to file for reimbursement and do all the administration work. You will need to send a few emails to catch up with people you met during the conference. Your overflowing mailbox might take a day to get sorted out. You'll need to catch up in the lab to see how things are going. There'll be people who need to talk to you, mail you or phone you. You'll be tired and busy. Plan accordingly.

Practical Application of Transverse Load Redistribution in Reinforced Concrete Solid Slab Bridges

I recently presented a paper titled "Practical Application of Transverse Load Redistribution in Reinforced Concrete Solid Slab Bridges" at the 9th conference on Short and Medium Span Bridges in Calgary.

The abstract of the paper is the following:

For an initial design or assessment of a reinforced concrete solid slab bridge, spreadsheet-based or hand calculations are typically used. The shear stress is compared to the shear capacity as prescribed by the code. The distributed loads result in a uniform shear stress at the support. Concentrated loads are less straightforward to take into account. It is known that transverse load redistribution occurs in slabs. To explore the topic of transverse load redistribution, experiments on elements subjected to a concentrated load close to the support were carried out. These elements had an increasing width, starting at 0.5 m and increasing with steps of 0.5 m up to 2.5 m, so that the effect of transverse load redistribution could be studied. The threshold effective width resulting from the experiments was then compared to load spreading methods, in order to give recommendations for the practical use with concentrated loads. It was found that the load spreading method as used in French practice is to be preferred. As compared to load spreading methods that were used previously, the French load spreading method results in smaller shear stresses at the support. This result allows for more economic designs and provides a better assessment tool.

The slides of the presentation are given below:

Practical Application of Transverse Load Redistribution in Reinforced Concrete Solid Slab Bridges from Eva Lantsoght

Recommendations for the Shear Assessment of Reinforced Concrete Solid Slab Bridges

At IABMAS 2014 in Shanghai, I presented a paper titled "Recommendations for the Shear Assessment of Reinforced Concrete Solid Slab Bridges".

The abstract of the paper is:

As a result of the heavier live load models and more conservative shear approaches prescribed by the recently implemented Eurocodes, a large number of existing reinforced concrete solid slab bridges in the Netherlands were found to be shear-critical. The beneficial effect of the transverse load redistribution in slabs under concentrated loads is not taken into account. To quantify this effect, a comprehensive number of experiments was carried out. These results are used to formulate recommendations for the assessment practice for the case of solid slab bridges. The recommendations focus on the effective width over which the axle load can be distributed and its lower bound, the beneficial effect of transverse load redistribution and the influence of the yield strength of the reinforcement on the lower bound of the shear capacity. These recommendations are implemented in the “Quick Scan” method, leading to a significant reduction of the shear stresses.

The slides of the presentation are uploaded here as well:

Recommendations for the Shear Assessment of Reinforced Concrete Solid Slab Bridges from Eva Lantsoght

Asking questions at conferences

One of the things that I know I should do, and should do more often, is asking questions during sessions in a conference. Most of the time, I feel a little too intimidated by the presence of other more senior researchers and worry that I might have missed out something, and end up not asking the question (a left-over of the Belgian education system, and a blatant showcase of impostor syndrome in action).

My style of working is mostly based on results, and not on talking. I hate having to toot my own horn. I don't appreciate a working style in which people talk a lot and deliver not much. But my stubbornly-working-away-in-the-background approach is sometimes getting in my own way. I often identify people at conferences with whom I'd love to have a chat - but I don't know how to approach them.

Before getting to the step of approaching people at random, I'm planning to work on my ability to ask questions during sessions - instead of just repeating the question in my head and then decide it might not be a good question. Here are the 3 things I'm going to try:

1. Practice small

The odds are I'm not going to raise my hand in the Big Annual Conference in My Field without hesitating. I'm going to test my ground at smaller events, during presentations at my own university, and at meetings of groups in which I already feel at home. In those situations, I hope to learn that I won't get decapitated when I ask a question, and from that experience, I hope to build up the confidence to move forward and start to raise my hand at larger gatherings.

2. Ask questions after the sessions

This technique is something I'm already practicing: if I have a question that, after deliberation with myself, seems not to be overly ridiculous, then I often keep it for the time after the lecture session, and approach the speaker with my question. It has happened that a speaker has brushed me off, but most of the time, I'm met with enthusiasm and end up chatting with said speaker for a fair amount of time. Admittedly, I much prefer this type of contact with a speaker over asking a question for a full room - but both ways of interacting with speakers are necessary (and when I present, I also enjoy getting questions during the Q&A as well as after the session).

3. Join panel discussions

I need to practice to "sit at the table" as Sheryl Sandberg would say, and as such I will push myself out of my comfort zone and into panel discussions at conferences. I can't use the excuse anymore that I'm just a students and trying to soak up some information - it's time to actually speak up based on everything I've learned over the past years. Again, I'm planning to start small, and try to speak up more at any meeting I attend - instead of just nodding my head or quickly frowning.

What are your experiences? How do you gain the confidence to join the debate at conferences?

Writing an abstract before finishing the research

It's Q&A time!

Recently, I received this mail from a reader:

I'm an early-stage PhD student in humanities, and my question is whether or not it is advisable to write an abstract for a conference before doing much of the research or any of the writing. I did this quite successfully for a graduate student conference, but I'm a bit more apprehensive about doing the same for my first professional conference.

Here's what Auntie Eva has to say on this topic:

I'd say - as goes with so many questions - "It depends".

IMO it depends on a few things:

1. Time schedule

There's a good number of conferences that require you to submit an abstract 2 years before the actual conference. For that situation, you have plenty of time between submitting the abstract and the due date of the paper - so you can plan to do your research in those months.

2. Contents of the abstract

How much of a grasp of the research do you have to make a conclusion to your abstract? Your concluding sentence does not need to be something like "it was found that property Y depends for X% on parameter Z", but you need to tell them if you are going to come up with recommendations, parallels - you need to point in the direction of what will be the result of the research already. So, if you have a schedule and know what you'll be digging into, you can have an idea of what TYPE of results you can promise in the abstract (the precise quantity can come later). Note that I write this from an engineering point of view - it might slightly differ in the humanities, although the general setup of abstracts and papers is the same along disciplines.

3. Tools

Do you have everything in your hands to get started on the research, or do you still need to sharpen your pencil and collect materials to make up your mind about where you will be going with this research? This question ties back to the time schedule part again as well.

With that said, I wrote my first abstract (for a conference for PhD students only, though) when I was less than 2 months in Delft, and the paper within 4 months of starting. It was all very preliminary, but it was a good lesson. By all means, conferences are one of the best places to learn, so if you have the chance, go to as many places as you can!

The Essential Conference Clothes

As I started to travel to conferences, I often found myself faced with the "What should I wear?" dilemma. Being in my mid twenties, I didn't want to give off the impression of being the "lost student" out there without any authority on the topic, nor did I want to dress like someone in their forties - and certainly I didn't want to wrong type of attention you might get as a women in a men's world.

While most advice online on what to wear to conferences and/or as a starting professor seems to focus on being neutral, I'm not too convinced about all the black, navy and grey that is being advised*. It's not because you decided to be a scientist, that you should adhere to society's impression that equates being a scientist to being boring!

Therefore, by all accounts, start from what you like wearing. Are you more comfortable in pants or do you prefer skirts and dresses? What colors do you naturally gravitate towards? I like wearing dresses, if necessary layered over long-sleeved t-shirts. As a result my natural choice would be a dress with a jacket. I prefer clothes with a lot of red and purple, so by no means I'd force myself to wear just navy, grey and black.

If you aren't sure about what style would work for you, borrow some items from a friend, a parent or a sibling. If nobody is willing to send you off with their best clothes to a conference, then go and weed through thrift stores to look for items that you want to try out.

Over time, and after visiting a large number of conferences, I've come up with the following list of essential clothes for conferences:

1. Comfortable shoes

Aerosoles Roler Derby Pump (see more short heel shoes)

An obvious choice - you don't want to be limping around because you can't walk around an entire day on those heels. I swear by a pair of Naturalizer shoes and a pair of Aerosoles that I scored for about 30 bucks at DSW.

2. A white blouse

Alexander Wang Combo Blouse (see more white sleeveless blouses)

A staple in every wardrobe: try to find a blouse that fits well at the shoulders, the arms, the waist and -please- does not bulge at the buttons.

3. A suit

BOSS Black Melange Jacket (see more BOSS Black)

An easy option if you want to test the waters at a conference. Comfortable, and it gives you so many options: you can dress it up and down with accessories, your choice of shirt and you can wear the separates too in different combinations.

4. Good jackets

Banana Republic Metallic Sweater Blazer - New sly stone (see more banana republic jackets)

Whatever you wear, it looks instantly more dressed up if you add a jacket. Take enough time to find a few jackets that fit well and that are versatile, then start combining.

5. Tops

Jane Norman Floral Peplum Top (see more long peplum tops)

At my age, I think it's OK to wear a more casual top combined with a suit or jacket, instead of opting for a blouse. I usually add a flowery top to a suit, to keep everything light and to add a bit of my liking and young age.

6. Conference dinner dress

Essentiel Candle Leaf Printed Silk Dress (see more floral print dresses)

Unless your conference is super-formal, I think that it's acceptable to show a little more of your personal taste in the choice of your conference dinner dress. I typically opt for a printed dress, or an all-red dress - because that is what I like. And often the choice is a dress by Essentiel (a mildly affordable Belgian label).

7. Opaque tights

Wolford Individual 100 Leg Support Tights (see more wolford hosieries)

If you go for dresses or skirts, tights are still a must at conferences. You might opt for bare legs, but I never do so, also because I like how tights flatten bumps and streamline everything.

8. A big purse

Village Convertible Leather Tote Bag, Brown - Cole Haan (see more cole haan purses)

Unless you want to drag the conference bag around the entire time, you need a large purse that can fit the conference program, notes, preparation material and whatever you like to have with you. I use an over-sized dark brown leather bag that I've had for many years, but I like how the leather is weathering.

If you want some inspiration, this post on My Laser Boyfriend has a lot of information, and great looks too.

*I might be biased as I was spent too much time wearing a grey - blue - white uniform during my schooldays.

What are your essential conference clothes? Do you have your favorites already, or are you still searching?