Hello, everyone.
This is Enta.
The other day, I heard from the anchor shop, and
They said they wanted to get a more accurate estimate.
As expected, when you transition from a craftsman-based system to an organized one, those kinds of issues tend to arise first.
If you can't provide an accurate estimate, you'll keep getting taken advantage of.
So, I gave him a quick lesson. (To the best of my ability.)
We need to know the daily construction volume and the daily cost.
I'll keep this brief.
(Example)
Rock bolts: 4.1 m each × 100 = 410 m; Drill hole diameter: 65 mm
Scaffolding provided. Skid drilling. Site Conditions II (Cost Estimation)
People: 25,000 yen × 3 people × 25 days
Drill: 600,000 yen/month
Compressor: 100,000 yen/month
Generator: 100,000 yen/month
Vertical Mixer: 50,000 yen/month
Graut Pump: 120,000 yen/month
Fuel: 120,000 yen/month
Paste this into Excel, and
| Artificial | 1,875,000 |
| Drilling Machine | 600,000 |
| Compressor | 100,000 |
| Generator | 100,000 |
| Vertical Mixer | 50,000 |
| Grout Pump | 120,000 |
| Fuel | 120,000 |
| Monthly Total | 2,965,000 |
How many 4.1-meter rock bolts can you install in a day?
For now, here,
Since we'll be doing injections every day, let's say 13 vials.
13 rolls × 4.1 m = 53.3 m/day
The important thing here is,
"We can drill a lot more holes here, so let's go with 20!"
Don't think that.
With a typhoon on the way, heavy rain, and all sorts of weather conditions, there are also various causes for concern.
ThatLossThat's what they say.
You need to calculate the daily average, including that.
Casing is a consumable, and bits wear out as well.
We need to include that in the estimate.
As a rough estimate, try dividing your monthly cost by 25.
2,965,000 yen ÷ 25 days = 118,600 yen per day
This is the daily minimum costwill be.
Divide this amount by the daily work volume.
118,600 yen ÷ 53.3 m/day = 2,226 yen/m
This is the unit price per meterwill be.
2,226 yen × 410 m = 912,660 yen
This is the case for Site Conditions II:
Lowest Prices for Drilling, Assembly, Injection, and Head TreatmentThat's it.
If the daily construction volume falls below the target, the project will run at a loss.will be.
However, this way, there’s no profit. There are no company expenses either.
Furthermore, given that the total length is 410 meters and the work is expected to proceed at a rate of 53.5 meters per day, the drilling and grouting will be completed in 8 days.
Will it take two days to process the head!?
We only work 10 days out of the month.
If you lease all the machinery, the price goes up by about 20 percent.
Except for monthly plans, costs will increase.
So, I'll multiply the total amount by about 1.2.
And then, transportation costs + plant installation costs + other negative factors
Taking all of this into account,
I think the price will rise to around 3,000 to 3,800 yen per meter.
Of course, statutory welfare costs (such as social insurance) and other expenses are separate.
Do a good job and get paid a fair amount.
We can build a good relationship with each other.
There was a time in the past when I, too, tried to make a profit by using subcontractors at low rates.
That was foolish of me. Looking back now, I wish I had just referred them to the general contractor.
I became consumed by my own self-interest. Part of it was that things were really tough, but,
To make sure I never do something like that again,
We decided to refer all cases that we cannot handle in-house.
I truly feel I did something very wrong to that company.
For civil engineering to improve even further,
I still think it's better to share the benefits with each other.
Both sides stand to profit. To make that happen, we need to understand our subcontractors as well.
What we need to know is how much the general contractor paid to win the bid from the government agency.
What were the details (cost estimate) of the winning bid?
Based on that amount, how much should my company charge for the job so that the general contractor can make a profit?
There are various challenges, but,
Please feel free to ask me anything.
I'll do my best to help.
See you later.
