specific columns sewer

Sewage specific columns

In the calculation of sewer lines beyond common columns, several columns appear, they are:

CINI
Initial contribution.
Sometimes an structure receives contribution of a large building. In these cases, you can add this initial contribution in this structure.
If one Flow rule is informed, it will be compared with this.

CFIM
Ends contribution.
Sometimes an structure receives contribution of a large building. In these cases, you can add this initial contribution in this structure.
If one Flow rule is informed, it will be compared with this.

SCINI
Sum of Initial contributions.
This value is given by adding up the cell value of the column CINI

CUTIL
This parameter is used to calculate fictitious extension.
If the pipe is crossing the street for example, there going contribution, just infiltration. In this case, the coefficient should be zero, if a road has sewer system in both sides, the coefficient should be worth 0.5 and if a network has only one extension side of the street, it is worth 1. So use with caution this coefficient. If you do not know what it is, uses 1.

TQ
This parameter that tells if a pipe needs drop pipe to connect to structure.
The need for this is defined in pipe drop rule. If the drop is greater than the maximum defined in this rule, this item will be marked with "Yes", otherwise "No"

EXTFIC
Fictitious length.
This value is used in the calculation of the contribution in motion and is given by:

EXTFIC = EXT * CUTIL

SEXT
Sum of pipes length (EXT).
This value is used in the calculation of the contribution in march.

SEXTFIC
Sum of fictitious pipes extensions (EXTFIC).
This value is used in the calculation of the contribution in march.

QIC
flow flowing in the pipe at the beginning of the project (calculated).
is given by:

QIC = SCINI + SEXT * TINF + SEXTFIC * TI
where:
SCIni: Sum of initial contributions in liters per second
SExt: Sum of lengths of pipe upstream of the passage, in meters
TI: infiltration rate in the pipe, in liters per second per meter

QI
flow value adopted in the beginning of the project that is adopted in the calculation.

is given by:
QI = MAXIMUM (QIC, Qmin)
Where:
QMIN is adopted minimum flow in parameters frame

QFC
calculated flow flowing in the pipe at the end of the project period, expressed in liters per second.
is given by:

QFC = SCINI + SEXT * tinf + SEXTFIC * TF
Where:
SCINI: Sum of initial contributions in liters per second
SEXT: Sum of lengths of pipe upstream of the passage, in meters
TF: infiltration rate in the pipe, in liters per second per meter

QESC
value flow adopted at the end of the project period.

is given by:
QESC = MAXIMUM(QFC, QMIN)
Where QMIN is adopted minimum flow in parameters frame

VI
Flow speed in the init of project period.
is obtained by iterative calculation also calculates LI

VESC
Flow speed in the end of project period.
is obtained by iterative calculation also calculates LAMINA

VC
Critical flow speed at the end of the project period.

Is obtained by:
VC = 6 * (Rh * g) ^ 0.5
where:
Rh is the hydraulic radius
g is the acceleration of gravity

If the final velocity VESC is greater than the critical speed, the maximum water height should be less than 50 %, according to the ABNT 9649, item 5.1.5.1, this value appears in the spreadsheet in red.

LI
water height in the initial project period.
This value is obtained iteratively with equations:

VI = (1/n) * Rh ^ (2/ 3) * INC ^ (1 /2)

Q = VI * Am

LI = h/DN

Rh = A / P

Where:
Rh : hydraulic radius in meters
A : Area actual water depth in the section of pipe in square feet
P : wet perimeter
h: height of the water
Q: Calculated flow

LAMINA
water height flow real sludge inside the pipe at the end of the project period.
This value is obtained iteratively with equations in rational method:

VESC = (1/n) * Rh ^ (2/ 3) * INC ^ (1 /2)

Q = VESC * A

LAMINA = h/DN

Rh = A/P

TTRAT
trative tension, in the beginning of the project period, when the flow rate is lower.

is given by:
TTRAT = GAMA * Rh * INC

This column is controlled by the variable minimum trative tension. If the value shown in this column is less than the minimum value, the cell shows the value red.