The Bridge Challenge is a competition that consists in making a model bridge.

Each team of 2 to 4 students from higher education will have to build a bridge in one day (9 hours) according to the criteria detailed below.
To be more efficient on D-Day, it is advisable to think about the structure of the bridge.
A plan will also be requested. The bridges will be evaluated according to several criteria, then, on the following day (Sunday morning) they will be loaded till they collapse.



■ Registration will be open from the 3rd March 2023 using the web site in the tab called “inscription” in French, or “registration” in English on the web page which describes the contest planned for 2021.

■ Registration will be closed when the number of teams has reached the number necessary for the smooth functioning of the contest. If this number is not reached, registration will be closed the 7th April 2023.

■ Each team must send, before the 7th April 2023, the registration fee and a copy of the student cards of each team member to the address or in e-mail (

Bridge Challenge ENISE

58 rue Jean Parot

42100 Saint-Etienne

■ The contest will take place during the weekend of the 29 to 30 April 2023, at Saint Etienne, “Place Jean Jaurès”.


          Registration fee

The registration fee allows you to enter the competition. They will be increased after March 5 deadline. For those who wish to have accommodation, they will be asked for an extra charge*.

Nomber of participants per teambefore March 25 2023 after March 25 2023
4 participants15€*17€**
3 participants20€*22€**
2 participants30€*32€**


* Accommodation on Friday evening and/or Saturday evening adds an extra 25 euros per person per night. Please note that the number of places is limited.
Payment is to be made by cheque to the order of “Bridge Challenge ENISE” or by bank transfer. After completing the registration form, a RIB will be sent to the team leader.



         2023 novelty

As announced in 2020. This year the competition will be divided into two categories: the architecture category and the resistance category.

Only the teams having chosen the resistance category will see their bridge being subjected to loading. The models of the architecture category will not be loaded or destroyed.

The best bridge in the architecture category will receive the architecture prize. The best bridge in the resistance category will be awarded the resistance prize.

Finally, all bridges will be evaluated to award the Engineering Award and the People’s Choice Award.

Translated with (free version)


          Architecture category

The teams having chosen the architecture category will compete with teams in the same category.
They will not be opposed to those who have chosen to compete in the resistance category. The bridges will not be loaded until they break and will not be destroyed during the competition.
Each team will be given an identical pack of different balsa profiles composed of 1 meter-long rods.


Materials (common to both tests):

  • 1 OSB board for the base of the bridge Ep 30 l. 610 l. 2000L’attribut alt de cette image est vide, son nom de fichier est image-7.png.
  • 2 blocks of cellular concrete siporex 200x250x300 (height)
  • 1 block 200x120x100
  • 1 jar of wood glue (160g approx.), 1 tube of super glue (5g), kitchen wire (10m), fishing line 6kg (40m length).
    Balsa wood in the form of 1m long sticks, with different sections (see table).L’attribut alt de cette image est vide, son nom de fichier est image-8.png.

The total weight is 299.46 grams.
Any materials (glue, balsa, thread, nails, screws, etc.) other than those provided are strictly forbidden.



The siporex blocks (200x250x300) will serve as abutments for the bridge, they will have an angle of 30° with respect to the OSB board and will be placed at 1130mm from each other. A pier consisting of a 200x120x100 block (L x W x H) is placed equidistant from the two abutments. As shown in the diagrams below:


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Architecture category:

Teams choosing the architecture category will compete with teams in the same category. They will not be pitted against those who have chosen to compete in the strength category. Bridges will not be loaded to failure and destroyed during the competition.

Resistance category:


The teams that have chosen the balsa strength category will be pitted against each other. At the end of the competition, the bridges will be loaded with weights ranging from 2.5kg to 5kg until they break linearly. The weights will be loaded as follows: 1, then 2, 3… etc,


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The bridge that has resisted the greatest load will be awarded the resistance prize. The structure will be judged broken when one of the stacked weights falls due to structural instability or structural failure. If a bridge does not break after placing all the weights at our disposal, the team will receive the maximum score on the strength evaluation.


  • The span of the bridge shall be 1160 mm, it is forbidden to reduce this span by cutting the medium board. The deck must be laid parallel to the ground. If the condition is not respected, the bridge will be disqualified from the resistance test.
  • It is possible to sand or cut the siporex blocks. However, it is forbidden to reuse the siporex scraps for the realization of the bridge.
  • A surface of 100*1160 mm for the bridges less than 300g on the deck, must remain free in order to carry out the loading.
  • OSB cannot be cut and drilled.
  • The deck medium board may be cut and drilled, but the resulting material may not be used to reinforce the bridge. The deck must have a minimum span length of 1160 mm for all bridges and must be parallel to the ground.
  • The balsa sticks cannot rest on the OSB board under any circumstances.
  • The kitchen wire as well as the fishing wire cannot be used as reinforcement in the deck, they can only be used in the installation of a cable-stayed bridge, subtended bridge, suspension bridge, …
  • Only siporex blocks can be painted.
  • It is permitted but not required to use the central siporex block as a support provided a template can be inserted under the deck.


Each group will produce a poster presenting their bridge (architectural and structural choices as well as plans for the bridge) before the competition date which will be displayed during the competition.

The structure will be judged broken when any of the stacked weights fall due to structural instability or structural failure. If a bridge does not break after placing all the weights at our disposal, the team will get the maximum score on the strength evaluation.

Scoring Rubric:

The bridges will be judged by a jury composed of architects and engineers, according to the following scoring grid:

■ Engineering (40 points)

Feasibility of the bridge in reality10 points
Relevance of the structure (Good use of a beam, …)10 points
Justification of technical choices10 points
Quality / aesthetics of the curve10 points

The architecture (40 points)

Quality of the finish of the model (smudged glue, badly cut wood, …)10 points
Harmony of the structure (Proportion)10 points
Architectural innovation10 points
Aesthetics / curve finish10 points


The winning team members in the different categories will receive an award.

Return of the models

Participants will not be able to collect their models.

Those that are not destroyed will be kept by the organising team and used for the communication of the competition.

Acceptance of the Regulation

Registration for the competition implies acceptance of all the terms of these rules.

The participants commit themselves to participate in the complete realisation of the model on 29 and 30 April 2023.

Intellectual property

Participants agree to accept, without being able to claim any remuneration or reward, the publication of their identity and the presentation of their project for informative, promotional or media purposes, within the framework of the present operation, whatever the method of dissemination of this information (brochures, leaflets, flyers, posters, press articles, internet site, etc.)

Each candidate agrees to give the organiser and its partners the right to use his/her image, name and surname free of charge for the exploitation of photographs, interviews or videos taken during the competition and which could be used by the organiser and its partners to promote this operation (internal and external communication, paper, video, internet etc.).

However, the organiser undertakes not to distribute participants’ contact details to third parties without their consent.

Possible changes

The organiser reserves the right to modify these rules at any time and to make any decisions it deems useful for the application and interpretation of the rules. The organiser may inform the participants and their legal representatives by any means of its choice. The organiser also reserves the right to modify, extend, shorten, suspend or cancel the competition, without prior notice, for any reason whatsoever. In particular, the organiser reserves the right to invalidate and/or cancel all or part of the competition if it appears that fraud or malfunctions have occurred in any form whatsoever in the context of participation in the competition or the determination of the winners. In such a case, it reserves the right not to award the prize(s) to the fraudsters and/or to prosecute the perpetrators of such fraud before the competent courts. Fraud shall result in the immediate disqualification of the perpetrator. The organiser and its partners shall not be held liable for any of the above and participants and their legal representatives shall not be entitled to claim any compensation or indemnity of any kind.

Information technology and civil liberties

Participants are reminded that in order to take part in the competition, they must provide certain personal information about themselves (surname, first name, email, telephone, etc.).

The purpose of collecting this personal information is to ensure the proper functioning of the competition. This information is recorded and saved in a computer file for the time necessary to take into account their participation, to determine the winners and to award the prizes. This information is intended for the organiser. Failure to communicate this data will result in not being able to participate in the competition. It will not be kept beyond the announcement of the results.

In application of law n° 78-17 of 6 January 1978 relating to information technology, files and freedoms, participants have the right to oppose, access, rectify and delete data concerning them. To exercise these rights, participants or their legal representatives must send a letter to the address of the Bridge Challenge ENISE association (see the “About us” page of the website).