HEC-22 Energy (Third Edition) - Additional Structure Losses

The second of three principle computational steps to computing energy losses through an access hole, according to the HEC-22 (Third Edition) procedure, is the summation of all additional structure losses. Total Additional Structure Losses ( $H_{a}$ ) is the relative step increase in energy grade line from the Initial Access Hole Energy Level ( $E_{a i}$ ) up to the value of the reported Energy Grade Line (In) ( ${E G L}_{a}$ ) at the upstream boundary side of the node.

{E G L}_{a} = E_{a i} + H_{a}

$E_{a i}$ = Initial Access Hole Energy Level. See also: HEC-22 (Third Edition) Entrance Loss.

The Total Additional Structure Losses ( $H_{a}$ ) is the combination of all additional structure losses due to benching, angled inflows, and plunging flows through the structure:

H_{a} = H_{B} + H_{θ} + H_{P}

$H_{B}$ = Additional loss for benching. See also: HEC-22 (Third Edition) Loss for Benching HEC-22 Energy (Third Edition) – Benching.

$H_{θ}$ = Additional loss for angled inflows. See also: HEC-22 (Third Edition) Loss for Angled Inflow.

$H_{P}$ = Additional loss for plunging flows. See also: HEC-22 (Third Edition) Loss for Plunging.