3.3. Productivity Calculation

And hope you remember these curves are valid only for these ideal conditions. So, 60 minutes hour but in your project in this problem we found that the machine is working for 50 minutes an hour. So, you are supposed to apply the job efficiency, you have to apply the correction factor accordingly. So, this curve is applicable for power shift mode, automatic usage.

Productivity curves are theoretical models that indicate how much work can be done under ideal conditions. These models assume that machines operate continuously for a full hour (60 minutes). However, in real-life scenarios, machines might not work for the full hour; for example, they might only operate for 50 minutes. When this happens, we need to apply a correction factor to account for the reduced operational time, which will adjust the expected productivity based on actual working conditions.

Imagine driving a car for a road trip. The manufacturer states that the car can travel 60 miles per hour under perfect conditions, but if there’s traffic and you can only drive for 50 minutes, you’d have to reevaluate how far you can actually go in that time. Just like that, if a bulldozer has to work for less than an hour, we need to adjust the productivity expectations accordingly.

But this curve value is applicable for a soil density of 1365 kg per meter cube. So, in our case the soil density is given us 1750 kg per meter cube in bank state that is to be noted the soil the bulldozer is going to do is of density 1750 kg per meter cube in bank state that is to be noted.

The productivity curve assumes a specific soil density of 1365 kg/m³ for calculations. However, if the actual soil density is higher, like 1750 kg/m³ in our example, it means the soil is denser. Denser soil requires more effort for the bulldozer to move, which ultimately impacts the machine's productivity. We need to make adjustments to the expected productivity to reflect this increased difficulty.

Think of scooping ice cream with a spoon. If you're scooping regular ice cream, it's smooth and easy. But if you're trying to scoop very hard, frozen ice cream, it takes much more effort. Similarly, denser soil is tougher to move, so we adjust our productivity expectations downward.

Then other things like operator the curve was drawn for excellent operator skill. So, in our problem the operator skill is average. So, accordingly you have to choose the correction factor and apply. So, your correction factor is going to be less than 1, because it is average is going to reduce your productivity.

The productivity curves are based on the performance of an excellent operator. If the operator's skill is only average, then we need to reduce the expected productivity using a correction factor, which is a value less than 1. This adjusts the ideal estimates to be more realistic based on the operator's ability.

Consider a cooking competition where a master chef can prepare a dish in 30 minutes, but if an average cook takes 45 minutes to do the same, they will not have the same output. Just like that, an average operator may produce less work in the same amount of time.

So, you are going to choose all the appropriate correction factors from the equipment handbook for this particular project condition.

In practice, correcting the productivity involves compiling various correction factors from an equipment handbook. These factors should take into account the conditions of the job site such as soil type, operator skill, and visibility. By multiplying all relevant correction factors, we arrive at a more accurate estimate of productivity under the specific project conditions.

It's like preparing for a test. If you know certain topics are harder for you, you'd spend more time studying them. Similarly, if certain conditions hinder work efficiency, you calculate those and apply more corrections to estimate productivity.

So, after you estimate the productivity you are asked to estimate the unit cost of proposed earthmoving operation per bank meter cube.

The unit cost of production is determined once we have calculated expected productivity. To find this cost per bank meter cube, we divide the total hourly cost of operating the bulldozer by its productivity (measured in bank cubic meters). This gives a sense of how much money is required for every unit of work done, which is critical for project budgeting and contract bidding.

Think about a lemonade stand. If you spend $20 on supplies and sell 100 cups of lemonade, the cost per cup is$0.20. Similarly, to determine how much each unit of earthmoving costs, you need to understand both your expenses and how much work you're able to produce.

Now let us find the product of all the correction factors. So, whatever correction factors we have discussed so far, let me summarize.

To finalize the productivity calculation, we multiply all the individual correction factors that have been previously determined. This comprehensive product gives a single factor that can effectively adjust the ideal productivity curve to reflect the actual conditions of the project, factoring in all the variances including soil type, operator skill, and equipment performance.

Imagine making a fruit smoothie. You might use bananas, strawberries, and yogurt. If you want to know the final flavor, you wouldn't just think about one ingredient but all of them together. Similarly, we consider multiple factors together to adjust productivity accurately.

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