3. Different Approach for Estimation of Productivity

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.

When estimating productivity, the ideal productivity curve is based on certain conditions. However, real-world conditions may differ—for instance, a machine may operate for only 50 minutes out of an hour instead of a full hour. This necessitates the application of a job efficiency correction factor. Job efficiency is computed based on the actual working time relative to the ideal working time, which impacts the expected productivity.

Think of this like a student preparing for an exam. If the exam is based on a full semester of study but the student only studied for 10 weeks, the student’s performance may be less than what is expected based on the full time of 16 weeks. To adjust for this, the student's effective study time must be considered, just as we must consider job efficiency in our productivity calculations.

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. But the curve, the production value what you have chosen from the curve corresponds to the productivity of 1365 kg loose meter cube.

The productivity curve used is based on a specific soil density, which in this case is 1365 kg/m³. However, the actual project involves soil that has a density of 1750 kg/m³. Since the productivity curves are calibrated against the ideal conditions, a correction factor must be applied to adjust the productivity values in light of the denser soil.

Imagine trying to push a heavy cart with fewer weights compared to one loaded with more weights. The dense soil is like the loaded cart; it requires more effort to push, thus reducing the bulldozer's efficiency. In turn, you would need to account for this extra effort in your productivity calculations.

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 curve assumes that an excellent operator is at the controls, which maximize efficiency. If the actual operator's skill is average, a lower correction factor will be applied to account for decreased performance. This means that instead of achieving the ideal productivity, actual productivity will likely be lower than the curve indicates.

Consider a basketball player shooting hoops. An expert player might make 9 out of 10 shots, while an average player may only make 6 out of 10. If we assume everyone is a superstar, we overestimate performance. Acknowledging skill levels allows more realistic expectation setting, just like adjusting productivity with operator skill.

Similarly, the material type, material type is non-cohesive silty sand, so that will definitely reduce the productivity. So, the correction factor is going to be less than 1.

The type of material being moved affects bulldozer productivity. Non-cohesive silty sand is generally easier to move than other types, but it still requires a correction factor since the performance might differ from the ideal condition assumed in the productivity curve. The productivity will be reduced, and thus the corresponding correction factor will be less than 1.

Imagine hauling different types of liquids. Water flows easily, but oil, which is thicker, takes more effort to move. Just as you need to adjust your methods based on the type of liquid, we adjust our productivity calculations based on the material type when using bulldozers.

visibility is poor in the problem what we have discussed. So, that will reduce your correction factor, the productivity will reduce obviously we are working for 50 minutes an hour, so accordingly the correction factor should be applied.

Poor visibility impacts the operator's ability to perform efficiently, thereby potentially lowering productivity. The visibility condition is less than ideal, which necessitates the application of a correction factor that will reduce the expected productivity.

Consider driving a car in foggy conditions. Your forward visibility is limited, so you drive slower and with greater caution, resulting in a longer travel time. Similarly, poor visibility in bulldozer operations will slow down work and thus affect productivity.

So, accordingly you have to choose the curve supply by the manufacturer. So, corresponding to what is -15% you have to find the correction factor. Obviously, I told you it maybe, so this is 0, the ideal curve is drawn for level terrain, so the grade percentage may go like this.

For projects involving slopes, it’s crucial to adapt the productivity curve to these conditions using correction factors. If a bulldozer operates on a slope, the grade percentage affects its ability to move material. A slope of -15%, for instance, means the machine is working downhill, which is generally easier and could increase productivity, therefore requiring appropriate adjustments.

Think of riding a bicycle downhill versus uphill. It’s much easier to gain speed going downhill. This concept applies to the bulldozer as well: operating on slopes changes the energy required, influencing the revision of expected productivity using correction factors.

Now let us calculate the product of all the correction factors. So, whatever correction factors we have discussed so far, let me summarize. So, one is your visibility correction factor 0.8, operator skill correction factor 0.75,...

After identifying all the relevant correction factors based on various conditions and operator skill, we multiply these correction factors together to arrive at an overall productivity adjustment. This final corrected productivity value is much lower than the ideal value initially derived from the manufacturer’s productivity curve.

Imagine baking a cake but each ingredient (like flour, sugar, eggs) is measured incorrectly. The end product doesn’t turn out as delicious because the adjustments were made poorly. Likewise, correct application of all productivity-related factors is essential to yield realistic productivity estimates.

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

Once productivity is estimated, calculating the unit cost of production comes next. This is calculated by dividing the total hourly cost of operating the bulldozer (ownership and operational costs) by the estimated productivity expressed in bank meter cubes per hour. This final value provides critical insight for budgeting and bidding processes.

Think of budgeting for a party. If you know how many guests are coming (productivity), you divide your total budget (operational cost) by the number of guests to figure out how much you can spend per person. Similarly, you calculate the cost per bank meter cube to manage the project's financial health.

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