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Pipe Flow Calculator (Hazen-Williams)

Determine water flow rate and velocity in pressurized pipes using the Hazen-Williams empirical equation. Ideal for civil engineers sizing water mains, irrigation lines, or fire-suppression systems.

Pipe Diameter (mm)

Pipe Length (m)

Head Loss (m)

Hazen-Williams Coefficient

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Civil

Flexible Pavement Thickness Calculator

Compute the required flexible pavement structural number using the AASHTO 1993 empirical design method. Used by pavement engineers to size asphalt road sections for a given traffic load, subgrade strength, and reliability level.

Design ESALs (applications)

Reliability Level

Subgrade CBR (%)

Serviceability Loss

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Key differences

	Pipe Flow Calculator (Hazen-Williams)	Flexible Pavement Thickness Calculator
Category	Civil	Civil
Inputs required	4	4
Result	Flow Rate (L/s)	Structural Number Required (SN)
What it does	Determine water flow rate and velocity in pressurized pipes using the Hazen-Williams empirical equation. Ideal for civil engineers sizing water mains, irrigation lines, or fire-suppression systems.	Compute the required flexible pavement structural number using the AASHTO 1993 empirical design method. Used by pavement engineers to size asphalt road sections for a given traffic load, subgrade strength, and reliability level.