Hello, everyone.
This is Enta.
Since I usually work on slopes like this one in the mountains, installing rebar, I have to be extra careful when working on construction sites in the city.
As expected, measures to address noise, dust, and other issues are needed...
There's nothing much to do out in the mountains, so I can really get down to work.
As expected, since we can’t start early or work overtime in the city, the construction time is shorter.
That does mean the price will inevitably go up, doesn't it?
So, this is a continuation of the previous post.
Retaining Wall Reinforcement Methods from a Slope Engineer’s Perspective (Part 1)
Retaining Wall Reinforcement Methods from a Slope Engineer’s Perspective (Part 7): Design
Let me make one thing clear from the start.
We are a public works construction company that specializes in the design and construction of public works projects.
We carry out construction in accordance with national design and construction standards.
The same applies to prefectures and municipalities.
For that reason, money is based on that standard.
Since it is paid for with tax dollars, the amount is determined based on fair judgment, soThere are absolutely no rip-offs or anything like that.Please keep that in mind.
The amounts I'm about to mention are based on national standards.
And that unit price plus on-site conditions.
Please keep that in mind when considering the matter.
I should really start with stone masonry reinforcement, but for now, I’ll list the reinforcement costs for L-shaped retaining walls (retaining walls).
Estimated Quantity
Reinforcing Bar Installer, 5 m
Top row: 9 pieces × 5 m = 45 m
Bottom row: 9 pieces × 5 m = 45 m
Drilling for drainage: 5 holes × 4 m = 20 m
Pressure plates: 18
Reinforcement Bar Insertion Drilling Costs
Site Conditions III
15,000 yen per meter
Actual market unit prices (The government-set unit prices do not include drilling depths of 5 meters; the maximum is actually 3 meters.)
Upper and lower levels: 90 m × 15,000 yen = 1,350,000 yen
If we apply time-based restrictions and length-based adjustments to this, the increase would be 1.15 + 0.2 = 1.35.
1,822,500 yen
Material Costs for Rebar Insertion Work (Extremely Confined Spaces)
| Product Name | Quantity | Unit | Unit Price | Amount |
| 0.5-meter rod | 10 | 本 | 2,400 | 24,000 |
| Coupler | 9 | 個 | 2,050 | 18,450 |
| Chip Bit | 1 | 個 | 13,700 | 13,700 |
| Cog Nut | 1 | 個 | 1,800 | 1,800 |
| Round Base | 1 | 枚 | 1,500 | 1,500 |
| Plate | 1 | 枚 | 800 | 800 |
| Pressure-receiving plate | 1 | 枚 | 35,000 | 35,000 |
| Total | 95,250 |
18 locations × 95,250 yen = 1,714,500 yen
Scaffolding Worker
2.0 m high × 10 m long × 60 cm wide
100,000 yen for the complete set (including draining)
Drainage Boring Worker
Retaining Wall Core Drilling Worker
1 location: 10,000 yen × 5 locations = 50,000 yen and up
Manual Drainage Boring Method
Drain Pipe Installation Worker (4 m per pipe)
24,500 yen / (4 m per piece) × 5 locations = 122,500 yen
Machinery Installation and Removal
Set 1: 280,000 yen
Material costs: 29,000 yen per unit × 5 units = 145,000 yen
| Item | Construction Costs | Cost of Materials | Total | Notes |
| Reinforcing Bar Installer (90 m) | 1,822,500 | 1,714,500 | 3,064,500 (34,040 yen/m) | A narrow lot with a rear width of about 50 cm |
| Drainage Boring (20 m) | 122,500+280,000=402,500 | 145,000 | 547,500 (27,375 yen/m) | Possibility of Rising Material Costs (Minimal) |
| Scaffolding Worker | 100,000 | 100,000 | ||
| Transportation Costs for Machinery, etc. | 150,000 and up | 150,000 | 4-metric-ton trucks by region | |
| Miscellaneous Expenses | 100,000 and up | 100,000 | It depends on the region | |
| Statutory Welfare Expenses | 50,000 and up | 50,000 | Typically recorded in the public sector | |
| Total | 4,012,000 | Maximum |
The unit prices for retaining wall reinforcement are as shown above.
These are merely reference values, and there can be significant variations depending on the site.
Anyway, living in such a cramped space is tough, so please bear with me on that one lol
That's damn expensive!!!
You might think that, but when you consider rebuilding the retaining wall...
And in reality, most of the retaining walls are about half this size.
There aren't many retaining walls this long at the moment.
(For a typical single-family home, the average cost is around 1.5 to 2.5 million yen.)
I can't afford to spend that much, but at least something for heavy rain protection!!??
If that sounds like you, just draining the water alone can be very effective!
Next time, we'll talk about the cost of stone retaining walls.
See you later.
