2. Loads

Dead loads (ﺔﺘﻴﻤﻟا لﺎﻤﺣﻷا) are the permanent/static forces acting on a structure. They include the weight of the structure itself and any other permanent fixtures such as roofing, flooring, and walls.

Dead loads are the forces exerted by the weight of all the components that make up a structure. This includes things like beams, columns, floors, roofs, and permanent installations like fixtures and fittings. Because they do not change over time, they are considered static loads. Engineers assess dead loads to ensure that the structure can support its own weight plus any additional permanent components.

Think of dead loads like the weight of a bookshelf filled with books. The bookshelf itself has a certain weight, and the books add to this weight. When you build a shelf, you must ensure that the wall or stand can hold not just the shelf but also the weight of all the books it will hold permanently.

Live loads (ﺔ(cid:5782)ﺤﻟا لﺎﻤﺣﻷا) are dynamic forces that vary with time. They include people, furniture, and any movable objects that can impose a weight on the structure.

Live loads are the loads that change over time. They are not permanent like dead loads. For example, in a residential building, once the furniture is placed, its weight becomes part of the dead load, but people coming and going represent live loads that can fluctuate. Engineers design structures to accommodate expected live load conditions during their lifespan.

Imagine a concert hall where chairs are set up for the audience. When the audience enters, each person adds to the load on the floor, which is a live load. If you design the floor to hold a certain number of people but then a larger audience arrives, the extra weight must be considered to ensure safety.

Wind loads (حﺎ(cid:5716)(cid:5610)ﻟا لﺎﻤﺣأ) are forces exerted on a structure by wind. These vary based on the building's height, shape, and location.

Wind loads act on buildings and structures due to pressure changes created by air movement. These forces can be significant, especially in high-rise buildings or structures located in open areas. Engineers must calculate potential wind loads and design reinforcement systems to ensure structures can withstand these loads without collapsing.

Think of how a kite flies. The stronger the wind, the more force it exerts on the kite, pushing it in different directions. Similarly, buildings face forces from the wind, which can push against walls and roofs, so they need to be designed to handle these pressures just like you should hold tightly to a kite when the wind is strong.

Snow loads (ج(cid:5629)ﻠﺜﻟا لﺎﻤﺣأ) refer to the weight of accumulated snow on a structure, which can be significant in colder regions.

Snow loads are the additional weights that accumulate on roofs and structure surfaces during winter. Depending on the climate and geography, snow can accumulate to considerable depths, adding to the overall load that the structure must support. Engineers must calculate expected snow loads based on local weather data to ensure safety.

Consider the snow piling up on a car's roof during winter. If you don't clear it, the increasing weight can damage the structure or even collapse it if too much builds up. Just like that, engineers consider how much snow a building could collect and design it to support that extra weight.

Earthquake loads (لزﻻﺶﻟا لﺎﻤﺣأ) are dynamic forces that occur during seismic activity, requiring special structural considerations.

Earthquake loads are forces created by the motion of the ground during an earthquake. These loads can be dramatic and highly variable, and they typically act laterally (side to side), impacting the stability of buildings. Engineers must consider the potential for earthquake loads in seismic zones to ensure structures can withstand powerful shaking without collapsing.

Think about how in a car, when you make a sharp turn, your body slides to one side because of the force acting on you. Similarly, during an earthquake, buildings experience shifting forces that act laterally, and engineers need to ensure they can ‘hold on’ against that force to prevent collapse.

Flood loads (تﺎﻧﺎﻁﻔﻟا لﺎﻤﺣأ) are caused by water accumulation that can exert additional pressure on structures.

Flood loads are the forces exerted on structures due to water accumulation during flooding events. This can lead to buoyant forces and additional hydrostatic pressure against walls and foundations. Engineers must design for potential flood scenarios, especially in flood-prone areas, to avoid structural failure during heavy rains or flood events.

Consider how a sponge absorbs water—when it gets too soaked, it becomes heavy. Similar to that sponge, as water accumulates around a building, the weight and pressure increase, which needs to be accounted for in designs to ensure it remains stable and doesn't ‘sink’ or be damaged.

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