RAM Concept calculates the percentage of load that is balanced by the post-tensioning within design strips. See Viewing balanced load percentages for instructions on accessing this information.

Each design strip segment reports two values:

• xx% DL Balanced
• xx% DL + RLL Balanced

The values reported are valid for the last Calc All (tendon changes after that are not reflected).

The values are calculated based on the total static moment for the span, for the balanced loadings and the dead and live loadings.

For a cantilever span, the effective load is:

w = 2M/L2

where

M	=	moment at first cross section
L	=	clear span

For a regular span (with supports at both ends), the effective load is:

w = 8M/L2

where

M	=	(M1 + M2)/2 - M3
M1	=	moment at first cross section
M2	=	moment at last cross section
M3	=	moment at cross section closest to midway between first and last cross sections
L	=	clear span

The percentage is defined as:

% = -100 Wb/Wl

where

Wb	=	effective load due to balance and transfer balance loadings
Wl	=	effective load due to load combination under consideration

("DL" or "DL + RLL")

There is no possible calculation for design strip segments that are not part of a span. These have an "undefined" balance load percentage.

The balance calculation may have some differences from the calculation available in the tendon plans. The difference are due to:

• diversion of PT effects
• clear span vs total span
• moment taken at first and last sections, not at support centerlines

In the calculations, "DL" is based on the "dead" loading types, and means:

Self Weight + Dead + Dead (transfer) but does NOT include Stressing Dead

In the calculations, "RLL" is based on the new loading types, and means:

Live (reducible) + Live (unreducible) + Live (storage) + Live (parking) + Live (roof) + Live (reducible)(transfer) + Live (unreducible)(transfer) + Live (storage)(transfer) + Live (roof)(transfer)

All of these loadings are reduced per the live load reduction code before addition to the total.