Everything about Wave overtopping experiment bare clay section 1-2 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 101;Wave overtopping experiment bare clay section 1-2;Strength test;Right before the start of a test on a section, the upper 20 cm (including the grass sod) will be removed over a distance of 3.5 m long and 4m wide. This section was located in between 10.5 and 14m downstream of the outflow opening of the overtopping simulator and subjected to regular waves to be used in the calibration of an erosion relation;False;False;True;False;False;False;2022-02-02 14:37:00;2022-02-02 14:37:00;1;4.0;;Other;;;;;;these tests are aimed at measuring the erosion rate of the clay layer underneath a grass sod on the landside slope of a levee, in order to enable the determination of the residual strength of the levee after failure of the grass. The results can be used to test and validate erosion models – both current models and future models.;Little is yet known on the erosion resistance of clay under wave overtopping, and how the results of small scale erosion tests could be used to determine the erosive behaviour of clay subjected to real life loads.;The grass was removed over a section of 4m wide, between 10 and 13.5m from the outflow opening of the wave overtopping simulator over a depth of 20 cm using a crane.;"At the middle section, the test starts with 20 of the largest waves, followed by a stepwise decrease. When choosing the volume to start with, the results obtained for the lower section are decisive. The initial wave volume will be one level higher than the wave volume at which a significant erosion rate occurred (in the order of 5 cm or more for 10 waves). This is to be estimated by Deltares and to be decided with the local test leader. However, if the series of waves at this higher volume in the lower section has not been completed because the test had to be aborted, then a lower initial volume may be chosen. This decision was taken in the field, by the local test leader and the advisor of Deltares. Three examples: 1. Suppose on the lower section no (or only little) erosion occurred during the 10 waves of 1500 l/m, an estimated increase of more than 5 cm during the 10 waves of 2000 l/m, the same during the 10 waves of 2500 l/m and that the test has been aborted after 7 waves of 3000 l/m. Then the test on the middle section will start with waves of 2500 l/m. 2. Suppose on the lower section hardly any erosion occurred during the 10 waves of 1500 l/m, there was a clear increase of the erosion during the 10 waves of 2000 l/m, and the test has been aborted after 3 waves of 2500 l/m. Then the test on the middle section will start with waves of 2000 l/m. 3. Suppose that in total only about 15 cm of erosion has occurred (as measured indicatively at the end of the test of the lower section), without a significant increase at any stage, and the lower section will remain open. Then the test on the middle section will start with waves of 3400 l/m. At every level, 20 waves will be applied, with a maximum 60 second interruption after every 10 waves. In the most extreme case (i.e., a situation like example 3 above), this means first 2 x 10 waves of 3400 l/m, followed by 2 x 10 waves of 3000 l/m, etcetera, and finally 2 x 10 waves of 500 l/m. The total ‘wave time’, including 13 x 60 seconds interruptions, will be about 1.5 hours.";10 Go Pro camera's were used;The camera's produced imaged which could be analaysed using photogrammetry to determine the rate of erosion as a function of the released wave volumes.;;;;;;Erosion relation for wave overtopping on clay;;True;False;False; All DATA concerning Wave overtopping experiment bare clay section 1-2 data_type;data_descripion;date_date;data_find;data_media;data_media_find ;;;https://stowanl-my.sharepoint.com/:f:/g/personal/llhpp_stowa_nl/Ejr1ykRvpXpGn68Jqkp1CEwBEgnYxnRQ16FdIVvNvRxkrw;; All EQUIPMENTS concerning Wave overtopping experiment bare clay section 1-2 No equipment added All SENSORS concerning Wave overtopping experiment bare clay section 1-2 No sensors added