A miser will pay twice
In a sense that is certain we had been happy to own St. Petersburg Mostotrest one of the primary clients because they handle a day-by-day procedure of bridges. Furthermore, Mr. Y. Petrov, whom had previously been the manager of Mostotrest in those days and dating an asian an expert that is great “patriot” of the Northern Capital bridges, demanded fr om us to make certain to begin with a long-lasting solution dependability associated with the bridges. Besides, he constantly emphasised that individuals reside and operate in St. Petersburg, and for that reason we now have no right to create ugly bridges or even to design simply a standard framework. The vector of development he has designated for Stroyproekt nearly fully complied with your perceptions that are own choices. But, the situation that is real Russian road industry into the 90-es could not expedite the task! Russian construction laws and SNIP norms (that are being currently upd ated) are dated back again to 60-es and 70-es once the engineering ideology ended up being mainly dedicated to materials saving. The economic effectiveness ended up being the fundamental requirements for design evaluation plus some Russian developers still follow through this approach. In comparison to this, we always strived to realize a dependable framework while supplying for logical usage of metal and concrete.
St. Petersburg bridges plainly illustrate the huge difference among these two design approaches. One of the Neva River bridges which is why a reconstruction has been produced by us design, Troitsky and Dvortsovy Bridges withstood about a century without major repairs. Besides, their structural elements mostly remained in reasonable condition and needed just some fix yet not replacement. Quite the opposite, the Lieutenant Schmidt Bridge (or Blagoveshchensky Bridge), which includes been recently reconstructed in accordance with our design, has quite a different sort of fate. After it had been reconstructed in 1936 – 1939 according into the design by Academician G. Peredery the connection could remain about sixty years just. The Volodarsky Bridge integrated 1936 in accordance with G. Peredery design could endure also less without having any repairs: it had been reconstructed in 1986 – 1993.
Within our time, we had been taught to adhere to the example up of G. Peredery, whom as an apologist of constructivism thought the greater rational was the greater beautiful. Besides, this principle ended up being so jealously utilized in the late Soviet period that currently the Peredery’s arches in Volodarsky Bridge of 1936 appearance alot more appealing compared to the current facade for the bridge that is same. But, the practice demonstrates that axioms regarding the connection dependability and durability don’t contradict the wonder concept. In the 60-es – 70-es they relegated the visual aspect of the back ground while pursuing the effectiveness and very nearly ignored connection architectural aspects. During party regarding the company’s 20th anniversary this year we had been extremely pleased to learn fr om certainly one of our visitors that individuals had found an innovative new bridge design approach since any connection created by our business had its individual “face”. In reality, it is not an innovative new but when generally speaking accepted and soon after forgotten approach. When making we have to always remember that the general public do value a artistic look of bridges along with other road works. If you don’t a professional, you would not have the ability to gauge the design that is structural you could constantly notice whether or not the framework is gorgeous or perhaps not. Consequently, we se t up an architectural team within the organization at the very beginning of our expert tasks.
Dispute about composite strengthened concrete
Therefore during our first separate tasks, partially consistent with Mostotrest needs and also to a point in accordance with this individual values we already designed to replace the prevailing approaches. The project that is first we had been assigned to function as the General Designer ended up being a little connection on the Slavyanka River at 676 kilometer of Moscow – St. Petersburg engine road (1995–1996). We now have proposed a design that is new of composite decks for little bridges that included a cast-in-situ slab and versatile studs manufactured from rebar metal. Regrettably, only a few the solutions because of this bridge were realized, nevertheless down the road in 1997–1998 our concept had been implemented for rehabilitation of this connection throughout the Saimaa Canal when you look at the town of Vyborg.
Bridge building in Soviet Russia had been commonly predicated on basic utilization of precast beams for tiny spans. Carriage way slab joints had previously been a point of this type of structure week. Whenever when you look at the last half of this 90-es Stroyproekt ended up being included into connection examination, design and supervision for the Russian Bridges Rehabilitation Program of Overseas Bank for Reconstruction and developing, we’d an opportunity to see with your very own eyes the situation that is terrible bridges had been. Only for some thirty several years of procedure the bridges made from precast beams got entirely away from purchase! And they were the absolute most bridge that is common. Consequently, we started initially to seek out an alternative solution to precast beams that will make sure durability that is structural. At that amount of time in Russia cast-in-situ tangible started to achieve some popularity which it currently had abroad. In specific, this technology ended up being employed for Moscow Ring path construction. Nevertheless, Moscow national along with its capabilities that are financial a very important factor, as well as the sleep of Russia was different things. For Russian contractors cast-in-situ reinforced concrete structures had been uncommon and inconvenient, they needed brand new equipment and work training and so their construction ended up being more costly generally speaking. For a long time our connection builders had used to precast structures that have been prefabricated at plant and erected at destination. We noticed that cast-in-situ reinforced concrete would hardly ever become extensive in Russia and an alternative was found by us which was really obvious as it had recently been mentioned in magazines of N. Streletsky, V. Bystrov, etc.
We began utilizing composite reinforced concrete for little spans
You could not really dream from it through the Soviet times: metal had been a material that is critical for defense industry and its particular usage ended up being strictly restricted. In bridge building, metal had been utilized just for over 60m spans that are long. This limitation ceased to occur just in 90-es so we began trying: first during the Slavyanka River venture and afterwards at Saimaa Canal.
Wanting to abandon precast slabs also to begin using cast-in-situ slabs, we have considered complete jobs as one example. A challenge with studs must be resolved. Soviet studs that are rigid broke slabs (and beams also) making them non-durable. Flexible Nelson studs are widely used today. And also for the connection over Saimaa Canal we was able to implement a fascinating innovation of o. Bakhurin, an expert of Scientific analysis Institute of Concrete and Reinforced Concrete. He proposed a welding that is special for ribbed club welding. Rebars might be welded with this particular device at spot, which was less costly. Unfortuitously, Bakhurin welding device (Gefest) had not been accepted for mass-production and after this contractors need to purchase foreign-made Nelson studs and international welding devices for them. a strength that is high ended up being useful for the Saimaa Canal Bridge along with flexible studs made from reinforcement metal in leave-in-place formwork. This project that is relatively small a kick off point for further professional growth of the business including elaboration of our very very own design techniques. Although we’d made our option, ideological disputes whether composite reinforced concrete ended up being suitable for brief spans continued for a number of years.
Whenever back 1999 Stroyproekt had been developing the style for St. Petersburg Ring path interchange with Primorsky roadway near Gorskaya railway section, we utilized composite structures not merely for the overpass that is main additionally for curved ramps of 60 m radius. It absolutely was an innovation too since curved beams had been regarded as tough to produce. But, our solution had been effectively realised and later it when designing the Ring Road facilities on we have often used. During those times construction associated with Ring path that were anticipated because of the town for way too long had simply started, and we also attempted to result in the Gorskaya interchange recognisable that is architecturally easy. We had been not necessary to take action; it had been our very own initiative. White ?-shaped (or trapezoid) pylons imitating entrance gates made this big structure look light and stylistically complete. This interchange started in 2001 became an expression of the brand new phase regarding the Northern Capital transportation development which had started because of the Ring path construction.