HL-93 Solver is an open-source program created for educational purposes. This program is not intended for commercial use.
Created by
Mohammad Majd, and not affiliated with any employer or organization.
Contact me with any questions, comments, or suggestions to improve this program.
I plan on adding more info to sections below, but here is what I have so far:
Background
The HL-93 is a live load model given in the American Association of State Highway and Transportation (AASHTO) LRFD Bridge Design Specifications.
It's a notional load, which is not intended to represent any particular truck, but is meant to envelope any legal load permitted on highways.
How this program works
The program splits each span of the multi-span structure into 10 members, and develops a global stiffness matrix for the entire structure. Based on that stiffness matrix, the program can calculate deflections, moments, shears, and support reactions.
The program is written in javascript, which provides a helpful math library with operations for matrices. The code is heavily object-oriented, and utilizes classes for nodes, members, degrees-of-freedom, etc.
Program Assumptions
According to AASHTO, axles that do not contribute to extreme force effects are to be neglected. This program does not have a feature
to account for this. Most commercial programs develop influence lines at every analysis point along a structure to determine which axles
contribute to the maximum/minimum force effects.
Future Features (maybe)
- HL-93 Lane Load and pattern loading
- User-defined vehicle
- Right now only 1 constant stiffness value(E * MOI) can be used for the entire structure. A possible future feature would be to allow the user to define different stiffness along the length of the structure.
- Show enveloped results in a table