Every pathway on Structure Bench presents a pre-built model designed to teach you something about how the platform works. As you work through the pathway, you'll build a clearer picture of what Structure Bench does and doesn't do.
In this 2D Beams and frames pathway, you'll be introduced to the 2D model canvas. You'll become familiar with the basic building blocks of a model, from nodes and members to sections, materials, loads and restraints. We'll solve some simple models and compare the results we get to well-known closed-form solutions you're likely already familiar with: wL2/8, wL/2, . This pathway is a bridge between your understanding of engineering first principles and the 2D editor.
We'll also cover the difference between a flexural (or frame) member and an axial (or truss) member. We'll take a closer look at the various restraint options available, hinges and the different load types you can apply to your models.
When we analyse structures, we rarely apply one set of loads - a more common approach is to apply characteristic loads, specify load factors and combinations and look at the combined influence of multiple load types acting simultaneously. Structure Bench supports this workflow through load combination and envelope features, which we'll also cover.
Of course, building a model is only half the story; extracting and interpreting the results of our analysis is a critical part of the process. So, we'll explore the various internal action diagrams (axial force, shear force and bending moment) as well as reactions and deflected shapes.
In this pathway, we'll work through ten steps. The models from each step can be opened alongside the pathway page, allowing you to investigate the model as you read. If you're a member, you can copy them into one of your own projects and try the changes each step suggests. This is by far the best learning experience - you'll learn way more by poking and prodding the models yourself! By the end of the pathway, you'll be able to:
read a beam or frame model in the editor - its nodes, members, sections, supports and loads - and build and solve one of your own,
read bending moment and shear force diagrams, the deflected shape and the reactions, and probe any point in the structure,
understand the impact of support fixity and hinges,
keep loads in cases, combine them with factors, find the pattern that governs, and read a response envelope,
apply various load types, including point actions and uniform and non-uniform distributed loads,
say what a first order, linear elastic solution assumes.
This pathway assumes that you understand what shear force and bending moment diagrams are and how flexural structures differ from pin-jointed axially loaded structures. Everything else is explained as it comes up.
Here are some resources from EngineeringSkills that you might find helpful before we begin:
A simple beam to start. A 6 m UB 305 x 165 x 40 subject to 20 kN/m, built from scratch, solved and checked against closed-form solutions.
Point loads and the results probe. A 50 kN load and a 30 kN m moment on the same beam. We see the jump in the shear diagram, the step in the moment diagram, and the probe for querying results at any point.
Fixity, releases and hinges. A cantilever, a propped cantilever and a beam with a hinge: what a fixed support, a prop and a hinge each do to the beam's response.
A continuous beam. Two spans over a middle support: the hogging and sagging moments and reactions - and the middle support as a spring.
Load cases, combinations and envelopes. Separated dead (permanent) and live (imposed/variable) loads, the imposed load on one span at a time (pattern loading), load factors, the derived self-weight case, and the envelope that identifies the governing combination at every point.
Non-uniform loading. A sloping rafter under a tapering snow load, a load over part of the span and an axial component along the slope: local against global axes.
A truss. A 24 m Pratt truss: an axial force in each bar, verified using the method of joints and the method of sections.
A portal frame. Columns and rafters as flexural members with sway under wind load.
Combined bending and axial in one model. A two-bay, two-storey frame with X bracing (axially loaded) members in one bay, compared against a frame without bracing.
Limits of a linearly elastic solution. The key assumptions that underpin a linear elastic analysis - what it provides and what it ignores.
OK, let's get into it - press Start with step 1: A simply supported beam below.