# Experimental Study on the Straw Flexible Space Assembly Flood Control System
## 4 Testing of Flood Control System
### Dynamic Water Test Results  
Figure 11 shows the results of the dynamic water test of the straw flood control system under 12 operating conditions. The overall strain pattern is that the greater the water flow force, the greater is the strain on the water baffles. The strain across the center is significantly higher than the strain on the left and right sides. The strains on the left and right sides largely overlap. There are some significant local differences, with the greatest  
Figure 10: Dynamic water test for the flood control system.  
Figure 9: Test data and numerical analysis data of hydrostatic test.  
difference between the middle strain and the left- and right-side strains at three levels of the flow force, and the smallest difference between the middle strain and the left- and right-side strains at one level of the flow force. The line graph shows that as the water flow force continues to increase, the gap between the strain in the middle and the strain on the left and right sides increases. As can be seen from Figure 12, the change in the baffle strain under the dynamic water test is the same for the flood control system with and without straw. The overall pattern of change in the flood control system in the dynamic water test shows that the test strain with the straw baffle is less than that without the straw baffle, indicating that the straw flexible space cushions the impact of the water force in the water baffle test so that the baffle strain is reduced to a certain extent.  
Figure 13 shows the strain distribution diagrams of the three levels of water flow forces under the action of different water levels (300, 450, 600, and 750 mm, respectively). Under the action of the water level forces of 300, 450, and 600 mm, the height of the highlighted part of the strain distribution diagram shows a slight difference from the height of the water level. Owing to the interaction between the water baffles, the height of the highlighted part of the stress distribution diagram is slightly higher than the height of the water level, and the strain value in the middle is higher than the strain values on both sides of the baffle. When the water level reaches 750 mm, the stress distribution in the strain distribution  
Figure 11: Flexible space strain diagram for different water flow forces.  
Figure 12: Flexible spatial water level–strain diagram with and without straw.  
diagram changes somewhat. The stress distribution gradually stratifies from the inside to the outside, and the strain in the middle of the water baffles is greater than that around the water baffles. At different water levels, the lower left and right corners of the water baffles, where the foot of the column is located, have the highest strain values. This indicates that the column is the main stress-bearing structure in the flood control system.  
Figure 14 compares the results of the dynamic water test and the numerical analysis of the water baffles under different operating conditions. The strain values from the dynamic water test and the numerical simulations are the same in terms of the variation pattern at each location in the flood control system. The strain values for each condition of the dynamic water test are slightly less than the strain values from the numerical analysis. As the water flow increases, the line graphs of the dynamic water test and the numerical simulation show an increasingly better fit, and the errors decrease. The error in the data for all conditions is between 5% and 8%.  
Figure 14: Comparison of dynamic water tests and numerical analysis.  
Figure 13: Strain distribution in flood control systems under three levels of water flow forces. (**a**) 300 mm. (**b**) 450 mm. (**c**) 600 mm. (**d**) 750 mm.