Length of Valley Curve & Highest/Lowest Point on Vertical Curves — Complete Guide
Complete guide to valley curve length formulas (comfort + HSD) for both L>S and L
Category: Highway Engineering
Length of Summit Curve — L>S and L<S Cases, Formulas & Solved Examples
Step-by-step derivation of summit curve length formulas for both cases (L>S and L
Length of Summit Curve — L>S and L
Step-by-step derivation of summit curve length formulas for both cases (L>S and L
Valley (Sag) Curve in Highway Design — Types, Comfort Criteria & Night Visibility
Complete guide to valley (sag) curves in highway vertical alignment. Four types, night headlight sight distance criterion, comfort criteria, cubic parabola design, and comparison with summit curves.
Summit Curve in Highway Design — Types, Parabolic Profile & Length Formula
Detailed guide to summit curves in vertical alignment. Covers all 4 types, why IRC uses square parabola, VPC/VPI/VPT positions, deviation angle N, and complete length formulas for SSD and OSD.
IRC Gradient Values for Different Terrains — Ruling, Limiting & Exceptional
Complete IRC gradient table for highway design. Ruling, limiting, and exceptional gradients for plain/rolling, mountainous, and steep terrain with design rules and drainage minimum values.
Vertical Alignment of Highways — Introduction, Gradient & Grade Compensation
Complete guide to vertical alignment in highway engineering. Covers gradient definition, four types (ruling, limiting, exceptional, minimum), effects on traffic, grade compensation formula, and IRC rules.
Transition Curve in Highway Design — Length Calculation, Clothoid & Setting Out
Complete guide to transition curves (clothoid/spiral) in highway engineering — three length criteria, shift formula, tangent distance, setting out methods, and IRC recommendations with solved example.
Extra Widening of Pavement on Horizontal Curves — Mechanical & Psychological Formula
Learn extra widening of pavement on horizontal curves — mechanical widening due to off-tracking (Wm=nℓ²/2R) and psychological widening (Wps=V/9.5√R) with IRC rules and solved examples.
Super Elevation in Highway Design — Formula e+f=V²/127R, Design Steps & Attainment
Complete guide to super elevation (cant/banking) in highway engineering. Formula derivation, IRC maximum values, 4-step design procedure, equilibrium SE, and attainment methods explained.