Risk assessment associated with negative pressure |
Intrusion potential |
Friedman et al. (2004)Friedman, M. L., Radder, S., Harrison, D., Howie, M., Britton, G., Boyd, H., Wang, R., Gullick, M., LeChevallier, D., Wood, D., & Funk, J. (2004). Verification and control of low pressure transients in distribution systems. Denver: American Water Works Association.
|
C1 |
Number of junctions with pressure < 0 mH2O |
92 |
Friedman et al. (2004)Friedman, M. L., Radder, S., Harrison, D., Howie, M., Britton, G., Boyd, H., Wang, R., Gullick, M., LeChevallier, D., Wood, D., & Funk, J. (2004). Verification and control of low pressure transients in distribution systems. Denver: American Water Works Association. adapted |
C2 |
% of junctions with pres.< 0 mH2O |
97.9% |
Cavitation |
C3 |
Number of junctions with vacuum pressure |
85 |
C4 |
Total time cavitation |
69s |
Severity of cavity index |
Martin (1983)Martin, C. S. (1983). Experimental investigation of column separation with rapid closure of downstream valve. In Proceedings of the 4th International Conference on Pressure Surges. Bath: British Hydromechanics Research Association (BHRA).
|
C5 |
|
9.3 |
S=severity of cavity index; a=celerity; TSC=duration when cavity occurs; L=length |
Surge Damage potential factor (SPDF) |
Jung & Karney (2011)Jung, B., & Karney, B. (2011). Pressure surge analysis of pumping stations for water distribution systems. Journal of Hydraulic Engineering, 137(2), 175-182. adapted. |
C6 |
|
-443.08 |
Hi = pressure < Hmin (allowable pressure) |
Risk assessment associated with positive pressure |
C7 |
|
2.88 |
Hi = pressure > Hmax (allowable pressure) |
Risk assessment associated with negative and positive pressure |
C8 |
|
-440.19 |
Hi > Hmax or <Hmin |
Δ pressure |
Jung & Karney (2006)Jung, B., & Karney, B. (2006). Hydraulic transient guidelines for protecting water distribution systems. Journal of Water Management Modeling, R246-09. adapted |
C9 |
ΔP = Hmax - Hmin |
281 |
Hmax |
C10 |
Minimum Pressure |
-10 |
Hmin |
C11 |
Maximum Pressure |
271 |
Positive and negative transient risk index |
Radulj (2009)Radulj, D. (2009). Assessing the hydraulic transient performance of water and wastewater systems using field and numerical modeling data. (Master’s thesis). University of Toronto, Toronto. adapted |
C12 |
|
99.82 |
C13 |
|
-9.52 |
Risk assessment associated with rapid change of pressure |
Damage index |
Shinozuka & Dong (2005)Shinozuka, M., & Dong, X. (2005). Monitoring and management of water supply systems. In 4th Korea Infrastructure Safety and Technology Corporation (KISTEC) International Seminar on Safety of Infrastructures. Jakarta: KISTEC.
|
C14 |
|
-86.8 |
D = damage index; H2 and H1 = pressure heads at a node at time t1 and t2, respectively |