cost/tonne for fabricated steelwork is a common etimating tool. First thing to consider is where are you working? rates will vary widely depending on your location.
A very rough estimate for fabrication in Asia would be
1. cost of steel
2. fabrication and one coat primer = cost of steel
3. overhead and profit = cost of steel
thus if steel cost US$400 per tonne then the fabricated cost would be US1,200 per tonne.
Erection will depend on the size of the crane etc.
mine was just an estimate, if (I don't have recent rates) the steel was US$400 per tonne then you could triple to make fabricated steel US$1,200 per tonne (this excluded erection). You have a figure of US1,000 per tonne not so different - how is that figure broken down?
your best bet is to call a fabricator. In NYC, bridge steel - material, fabrication, delivery, erection, and painting - runs about $2 to $2.50 per pound; $4 to$5 K per ton.
There are several factors to consider, such as - location of the fabricator, shipping, site constraints for erection, complexity of the project, working hours,client requirements (DOT's tend to be more stringent than private owners), union vs. non-union, Buy-America provisions.
You could also look in Means and make the necessary adjustments for location; that should put you in the ball park.
I recently checked fabricated costs here in the southeast U.S. and found $1400 to $1600 per ton on our typical single story jobs. Not sure how much erection would add to that.
Zambo's link gives a breakdown of materials, engineering, fabrication, erection, etc., for buildings. Does anyone know of a similar resource for bridges?
In Australia we use the following rates for order-of-magnitude estimates of mining and minerals processing structures:
Supply AUD 2,500/tonne (~USD 1,821/ton)
Shop Detailing AUD 500/tonne (~USD 364/ton)
Fabrication AUD 3,000/tonne (~USD 2,185/ton)
Transport AUD 150/tonne (~USD 109/ton)
Erection Labour AUD 2,400/tonne (~USD 1,748/ton)
Erection Plant AUD 1,200/tonne (~USD 874/ton)
TOTAL AUD 9,750/tonne (~USD 5,339/ton)
Rates would be somewhat cheaper for city and suburban structures. We pay a premium for labour, plant and transport due to the remote nature of most of our mine sites.
I was an estimator for a northern-midwest steel fabricator 5 years ago. At that time, fabricated and delivered, pre-bid price per ton was $1200 to $1500 per ton for structural. $1500 to $2500 for miscellaneous steel.
Call a local contractor or erector for erection costs.
Notice that I gave you the "pre-bid" price for steel. "After-award" prices for steel are higher. That is a topic for another thread if anyone is interested in discussing "Why are steel prices higher after the bid date?". "After-award" charges or "adds" to the project is one of the many reasons I decided to leave that particular job.
Just checked a recent job - a two story building, about 60,000 sf. Cost of steel was about $2000 fabricated, plus about $1000 for erection. So a total of about $3000 per ton. This is for the south U.S.A.
Cost of steel per ton is about USD 777 and fabrication + erection cost is about USD 266. But this is for industrial applications upto 14 meters height. This may be high for high rise buildings but fabrication and erection costs generally do not cross the supply cost.
If we need not have to go for RT of the welds, the fabrication cost can be a bit lower.
