2.1. Definitions of Volume in Different States

Whenever you express the volume, you should be very specific that whether you are expressing the volume in the loosen state or bank state, that is natural state or in the compacted state.

Volume can be measured in different states of material. The loosen state refers to the condition when the material has been disturbed and is not compacted, while the bank state refers to its natural, undisturbed condition. It's important to specify which state you are referring to when discussing volume, as it can have significant implications for calculations in earth moving and excavation projects.

Think of a bag of popcorn. When you first pop the corn, it expands and becomes airy and fluffy. This is similar to the 'loosen state'. But if you were to press that popcorn down into a flat bag, it would become denser and more compacted—this would represent the 'bank state'. Knowing which state you're measuring helps determine how much material you really have.

The production here is expressed in loose meter cube per hour, that means you have cut the earth and loosen the material after loosening in it, what is the productivity.

Productivity in earth moving operations is often measured in loose meter cubes per hour. This metric reflects the amount of earth that has been cut, loosened, and is ready to be moved within an hour. To calculate this value, you typically take the blade load (the amount of material the bulldozer can push) and divide it by the total cycle time (the time it takes to complete the push, return, and maneuver).

Imagine a worker loading boxes onto a truck. If he can load 100 boxes in an hour, his productivity is 100 boxes per hour. If you disrupted his flow, taking a moment to reposition or adjust would reduce the number of boxes he loads. Similarly, bulldozers have cycle times affected by several factors that determine how much earth they can move.

It is nothing but your blade load divided by the cycle time. So, how to determine the blade load just now we discussed.

To estimate productivity accurately, you must know both the blade load and the cycle time. Blade load can be assessed from the manufacturer's specifications or prior experience. Cycle time is made up of variable times like the push and return times, and fixed time, which includes maneuvering time. The cycle time is crucial as it indicates how long it takes to push material, return to the starting point, and make necessary adjustments.

Consider an assembly line in a factory. If a worker can only assemble 5 toys in 10 minutes but needs to stop for 2 minutes to fetch more parts, their productivity decreases. If they could assemble 5 toys with no breaks, that would maximize their productivity, similar to how measuring cycle time can help determine the bulldozer's productivity.

You should know that your machine is not going to be operated for the entire 60 minutes in an hour.

In real-world scenarios, a bulldozer will often not be operational for a full hour due to various interruptions—such as waiting for the loading of material or machinery downtime. This translates to a concept called job efficiency or working efficiency, which is the actual productive time the vehicle spends working versus the total time available. This efficiency must be calculated to obtain realistic productivity metrics.

Think of a student studying for an hour. If they spend 45 minutes actively studying and 15 minutes distracted by their phone, their efficiency is only 75%. Understanding and applying this concept in construction work can lead to more accurate project estimates.

The unit cost is nothing but cost per loose meter cube. Say I am going to find it in the loosen state cost per meter cube of earth moved.

To estimate the cost of moving earth in construction projects, you take the total hourly operating cost of the bulldozer and divide it by its productivity in loose meter cubes per hour. This gives a cost per unit of earth moved, which is critical in bidding and project management as it helps determine project feasibility and financial planning.

Think of running a restaurant. If you spend $100 an hour to keep the restaurant open and you serve 20 meals, your cost per meal is$5. Similarly, knowing how much it costs to move a meter cube of earth can help construction managers avoid financial pitfalls.

These production curves will have a relationship between the dozing distance and the production.

Production curves are graphs that illustrate the relationship between dozing distance (how far the bulldozer moves material) and the productivity rates. Manufacturers provide these curves to estimate how efficiently a bulldozer can work under standard conditions. However, real conditions often differ—therefore, correction factors based on site-specific challenges (like slope or soil type) must be applied to adjust the expected productivity from the curves.

Consider a professional athlete's performance. A standard training manual might show expected performance under ideal conditions (good weather, no injuries). However, a real athlete may need to consider injuries, slippery fields, or time constraints. Just as athletes must adapt their practices based on actual conditions, engineers must adjust expected productivity based on real-world factors.

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