Category

Fundamentals

The mechanics behind load takedowns: tributary areas, load paths and how forces find the ground.

Fundamentals

Hospital and Imaging Equipment Loads

A hospital floor is a set of very different zones, not one rate. Scanner masses, shielding, vibration criteria, and the loads hanging from the soffit.

Elena Marchetti··11 min
Fundamentals

Library and Archive Storage Loads

Shelved paper is heavier per square metre than almost anything else a building holds. Static stacks, mobile shelving on rails, and why deflection governs.

Sam Rivera··11 min
Fundamentals

Assembly and Crowd Loads Explained

Assembly floors are where people really do reach the code value. Unreduced rates, synchronised movement, barrier horizontal loads, stages and stairs.

Elena Marchetti··10 min
Fundamentals

Construction Loads, Shoring and Reshoring

The heaviest load a slab carries usually arrives before the building is finished. Wet concrete, props, stacked pallets, and how load shares between levels.

Sam Rivera··11 min
Fundamentals

Swimming Pool Loads on a Suspended Slab

Water is 9.81 kPa per metre of depth, permanent and exact. Depth profiles, tank self-weight, balance tanks, and why an empty pool can govern.

Elena Marchetti··10 min
Fundamentals

Earth Pressure Loads on Basement Walls

Earth pressure depends on whether the wall can move, not on what it looks like. At-rest versus active, water as its own case, surcharge, and uplift.

Elena Marchetti··10 min
Fundamentals

Concrete slab self-weight calculation

Slab self-weight is thickness times density. Reinforced concrete is about 25 kN per cubic metre, so a 150 mm slab weighs about 3.75 kN per square metre. Here is how to get it right.

Sam Rivera··4 min
Fundamentals

One-way vs two-way slabs: which tributary model to use

Whether a slab spans one way or two changes how load reaches the beams, and what shape the tributary areas take. Here is how to tell them apart and when the distinction actually changes your numbers.

Sam Rivera··6 min
Fundamentals

Triangular and trapezoidal loads on beams

A two-way slab loads its beams with triangles and trapezoids set out by the 45-degree rule. Here is where the shapes come from, the equivalent UDL, and a worked example.

Sam Rivera··4 min
Fundamentals

The 45-degree rule for tributary area

The 45-degree rule sets tributary boundaries by bisecting the angles between supports. Here is what it is, how it relates to the midline method, and when it applies.

Sam Rivera··4 min
Fundamentals

Tributary width for a beam, explained

A beam's tributary width is half the spacing to the parallel member on each side. Multiply it by the floor load for the uniform load on the beam. Here is the method with numbers.

Sam Rivera··4 min
Fundamentals

What is a load path in a building?

A load path is the continuous route a load follows to the ground. Here is what it means, the gravity and lateral paths, and why continuity and redundancy matter.

Elena Marchetti··4 min
Fundamentals

How to calculate tributary area for a wall

A wall collects a tributary strip, not an area like a column. Here is how to find its tributary width, turn it into a line load, and where the strip method applies.

Sam Rivera··5 min
Fundamentals

Tributary area on an L-shaped floor

The re-entrant corner of an L-shaped floor is where hand tributary sketches drift. Here is why, how clipping to the outline fixes it, and the area-balance check that proves it.

Sam Rivera··5 min
Fundamentals

What is superimposed dead load (SDL)?

Superimposed dead load is the permanent weight added on top of the structure's self weight: finishes, services, ceilings and partitions. Here is what counts and typical values.

Sam Rivera··4 min
Fundamentals

How to calculate a wall line load

A wall's line load is its weight per metre of length: height times thickness times unit weight. Here is the method, typical material weights, and a worked example.

Sam Rivera··4 min
Fundamentals

Tributary area vs influence area

Tributary area is the floor that loads a member; influence area is the larger area whose load affects it. Here is the difference, the K_LL factor, and why it drives live load reduction.

Sam Rivera··4 min
Fundamentals

How loads transfer from a slab to beams

A slab hands its load to the beams that support it, as a uniform strip in one-way action or as triangles and trapezoids in two-way action. Here is how, with the load shapes.

Sam Rivera··5 min
Fundamentals

Area load vs line load vs point load

Loads come in three forms: area loads on slabs, line loads on walls and beams, and point loads at columns. Here is what each means, its units, and how they convert.

Sam Rivera··4 min
Fundamentals

Tributary area: edge column vs corner column

An edge column carries about half a bay; a corner column about a quarter. Here is why, with the geometry, the load ratios, and a worked comparison.

Sam Rivera··5 min
Fundamentals

How to calculate tributary area for a column

A column's tributary area is the floor region nearest to it. Here is the half-bay method, the interior, edge and corner cases, and a worked example.

Sam Rivera··5 min
Fundamentals

Dead load and live load calculator (free)

Need to turn floor build-ups and occupancy into dead and live loads fast? StructLoads is a free tool that computes them and carries them through a full load takedown.

Elena Marchetti··4 min
Fundamentals

Dead load vs live load, explained

Dead load is the permanent weight of the structure; live load is the movable weight it carries. Here is the difference, typical values, and how each is factored.

Elena Marchetti··4 min
Fundamentals

Beam tributary width calculator (free)

Get a beam's tributary width and uniform line load without the sketch. StructLoads is a free tool that computes the strip each beam collects and turns it into a UDL.

Elena Marchetti··4 min

← All posts