Everything about Levee Challenge 2022 - Team DVW - Use of swelling clay
id;activity_name;activity_type;activity_descriptor;breaching;animal;erosion;temporary;levee_survey;prolonged;start_date;end_date;date_length_day;date_length_hour;date_other;levee_stretch;location_x;location_y;location_z;location_descriptor;location_other;objectif_important;objectif_knowledge;pre_condition;act_des;monitoring_process;monitoring_reasoning;limits;during_activity;post_activity;activity_result;results_conc;knowledge_desc;ref_links;wrk_1;wrk_2;wrk_3;key_info
91;Levee Challenge 2022 - Team DVW - Use of swelling clay;Exercise;The Levee Challenge was a physical challenge in which groups of students and professionals were asked to repair the outer slope of a damaged grass covered levee.;True;False;True;True;False;False;2022-02-09 08:00:00;2022-02-11 17:00:00;3;;The damage had to be repaired within a time frame of 3 hours. Testing happened in the following days.;XI;51.350779;4.221762;;Test section on Dutch Levee. The slope is assumed to be 1:2.5.;;The Levee Challenge was a physical challenge in which groups of students and professionals were asked to repair the outer slope of a damaged grass covered levee. The groups need to take into account the efficiency, innovative and durable solutions for their protection measures. The reparation of the levee needed to be sufficient to withstand a series of wave overtopping generated with a wave overtopping simulator.;The use of swelling clay as a semi-permanent emergency measure.;Lower part of the levee was damaged by heavy traffic. Prior to the tests, 4 spots on the levee were damaged to make repairs. At the upper part of the levee slope, a cliff was dug with a width of ~1.5 m (parallel to levee slope) and a depth of 0.5-1m (deep enough to penetrate the upper clay layer).;After the repairs were done, wave overtopping tests were carried out during a 6 hour period. Within this 6 hour period different storm scenarios were tested, with significant wave heights of 1 or 2 m, and specific discharge ranging from 50 to 200 l/s/m.;;;;"See Report for more information and pictures.
- The vibrating plate was not really useful to condense the clay granules.
- We did not remove the sandbags we placed in the beginning as a temporary threshold to
work against. During the overflow tests, this provoked a water jump that could have been
avoided. Actually, knowing now how the clay core behaves, we believe it was not necessary
at all to place those sandbags. 
- We are not sure it was necessary to use screed nets between the 20 cm thick layers of clay
granules, since the clay core seemed to be very stable.
- We are not sure it was necessary to fix the first piece of geotextile as we did it. Since the
whole construction did not move at all during the overflow tests, it was probably sufficient to
cover the clay core with a first loose piece of geotextile, stabilised with sand bags.
- We finished the clay core up to approx. 10 cm under the ground level of the dike, in order to
fill the upper part later with a layer of soil and to be able to sow after the so called “flooding”
danger was gone. 10 cm seemed to be insufficient, since the clay core swelled some more
during the overflow tests and the upper surface of the clay core reached the ground level of
the dike. We believe it would have been better to finish the clay core approx. 20 or 30 cm
under the ground level of the dike, and to fill up the gap above with sand bags to obtain a flat surface before putting in place the final geotextile fixed with reinforcement nets. The
sandbags could then be replaced after the storm by an appropriate layer of soil.
- The plugs (with roundels) we used were too small. The self-made anchors of bended Ushaped reinforcement steel on the contrary happened to be very efficient.";"No damage. By the end of the test, there was decided to remove the reinforcement nets and
geotextile to see how the bare clay core would resist when exposed to the violent waves. It
did not take long before the clay core started to erodee.";;"The use of clay granules (in bags of 25 kg) is proven to be a very plausible and handy technique to restore the part of the clay layer of an eroded dike, and it allows to finish the restoration of the dike with a layer of soil to be sown once the danger of flooding has passed. It may even be possible to carry out this restoration without the screed nets we used to
reinforce the clay core. Since this technique requires few one-use materials, and it allows the dike restoration to be finished very easily after the storm, it can also be considered as an ecological and sustainable one.";;;False;True;True;


All DATA concerning Levee Challenge 2022 - Team DVW - Use of swelling clay
data_type;data_descripion;date_date;data_find;data_media;data_media_find
Report;Overview of testing and report;2022-09-01;https://stowanl-my.sharepoint.com/:b:/g/personal/llhpp_stowa_nl/EbyBbKIhAepPjbS9BKuJyfcBqU8wrsEa7nHqQxm2Szn5WQ?e=g4PROS;;
media;;;https://stowanl-my.sharepoint.com/:f:/g/personal/llhpp_stowa_nl/EnpM0eICcPhAvYNX7ZLKdJwB5go7YgvpsaRV8c6egJhr-A?e=dVveLb;;


All EQUIPMENTS concerning Levee Challenge 2022 - Team DVW - Use of swelling clay
equip_type;equip_usage
Overtopping generator;Able to simulate overtopping over a dike.


All SENSORS concerning Levee Challenge 2022 - Team DVW - Use of swelling clay
No sensors added