Polystyrene foam material used in the construction of the hollow deck

Abstract: Polystyrene foam has a perfect closed cellular structure very low water absorption, low thermal conductivity, high pressure resistance, aging resistance, etc. become industrial and civil buildings ideal insulation material. In this paper, through the introduction of Hotan Bobo Na hydropower project construction of highway bridges in common use polystyrene foam core instead of the traditional mold of successful attempts that the capsule tube compared to traditional air-molding, shaping template, templates with easy-to-wood combination procurement, ease of processing, low cost, simple operation, and other steps to reduce the significant advantage of special suitable for a small number of other hollow road bridge construction. 1 Hydropower Station Project Overview Bo Bona is located on the River Hydropower Station in Hotan Karakash River. Power Station located upstream Wuluwati Water Control Project about 30km, from Hotan city 41km, from Uluwati Dam dam 2.85km. Project by the dam, outlet structures and power diversion system and powerhouse and other major buildings consisting of medium-sized Ⅲ works. Normally, the reservoir 1855.0m, the total capacity of 002.4 million cubic meters, maximum height of 27.0m; shaft weel length of about 12km; power station capacity of 150mw, guaranteed output 35.0mw, annual average generating capacity of 666 million effective kw * h. 2 polystyrene foam replacement bridge plate precast hollow core mold highway bridge located on Bo Bona Station power house tailrace, bridge length 43.32m, load rating Ⅱ grade highway bridge from east to west across the tailrace, connected to Hotan National secondary roads Wuluwati hub. Two for two-span road bridge 13m oblique hollow bridge, precast hollow cross 7 per total 14, hollow size φ390mm. 2.1 polystyrene foam mandrel selected reference road and bridge construction experience, common precast hollow mandrel tube mold air capsules. Air capsule tube mold can be reused, the same applies to sizes, a larger number of prefabricated factory; the price is high, while the number of small prefabricated panels uneconomical; two air capsule tube mold, only a single piece of hollow plate Prefabricated, need to be strong after the construction ends stripping Concrete plug. Slow progress in increasing steps need professionals to operate pneumatic level, floating control, the release time is not easy to grasp the essentials of the hydropower industry in view of the lack of road and bridge construction is relatively less skilled personnel and construction experience. Use air tube mold capsules should not be used there is a big risk. There is also a circular hole hollow tubes made rigid mandrel tube mold than the air capsules intuitive to apply to a small number of precast hollow plate once purchase multiple simultaneous pre-save period without forming a more economical form removal. Due to the remoteness of Hotan Prefecture, to determine the program after the φ390 rigid pvc pipe out in the Xinjiang region, after the required production orders shipped from Shanghai by the manufacturers; because when a small number of manufacturers, when there is a great arrival uncertainty; with highway bridge as the only path to the bird 鲁瓦提 Wada traffic arteries and 波波娜 construction of large transport station, its early opening is significant. To this end, according to the local color steel industry developed clues found produce color steel sandwich manufacturers, selected a more suitable alternative material polystyrene foam. 2.2 precast hollow construction process control highway bridge precast hollow hollow overall size and reserve size are small, so the use of a cylindrical polystyrene foam core mold once laid, panels forming a pouring way. That is, after installation of prefabricated steel reinforcement and the outer mold is completed, temporarily blocked the installation of concrete transverse reinforcement, the first docking with transparent tape to the design length of grind root polystyrene foam cylinder mandrel penetration board, the use of panels Design of Reinforced and erect ribs, accurate installation mandrel positioned firmly reinforced and reinforced, and finally completed the installation of reinforced concrete capping and bulkhead reinforcement template. Casting process should be taken to avoid a focus on cutting excessive vibration or excessive vibration leakage occurs due to leakage of vibration will affect the concrete dense, it will cause excessive vibration floating mandrel or offset. A blocked concrete and pouring a concrete slab forming the body, so without removing the mandrel, compared pvc pipe mandrel also save capped in concrete mold, do not worry about the advantages of mandrel when vibrated rupture. Taking into account the excess weight without removing the mandrel may change deck design load, the choice of 10kg per cubic meter of polystyrene foam, monolithic hollow mandrel weight increase after the increase 15kg, only the weight of the hollow design 1/1000, cloth effect on the deck after both forces can be ignored. 2.3 precast hollow mandrel economic comparison only direct cost comparison, 14 hollow capsules with three sets of air tube mold (including spare one set) is about 12,000 yuan, while the road bridge two precast hollow polystyrene foam used in all materials. Including equipment renovation fees of about 8000 yuan, 4000 yuan cost. 3 polystyrene foam alternative prestressed hollow mandrel traffic bridge deck is 波波娜 Station Entrance Road Bridge, located in the powerhouse tailrace station tail 0 + 137.100m, was the only channel into the power house rhyme 波波娜 Station also key parts of the flood season of flood control Bobo Na Hydropower Station. Traffic load rating of highway bridge Ⅱ, basic intensity Ⅶ degrees, bridge length 30m, 20m single span bridge was prestressed concrete hollow oblique, the slope of 30 degrees. 3.1 polystyrene foam mandrel selected traffic bridge PRECASTING hollow size of 74cm * 69cm, it belongs chamfered rectangular cylinder, the more road bridge precast hollow hollow dimension wider and taller, mandrel panel production relative Simple. Under normal circumstances such a hollow can enter the operation should be adopted setting a template, hollow in the larger number of plates, the advantage is obvious; if the duration of loose, shape template sets can also be used, the cost is not high. But this project is only six traffic bridge deck, all with styling templates expensive, longer duration of use of a single set of core mold, then recycled. Comprehensive comparison, or the use of polystyrene foam mandrel can save more economical material, but also guarantee period. 3.2 polystyrene foam mandrel construction process control using polystyrene foam shaped mandrel, mandrel how to ensure vibration compacting concrete bottom, how to ensure the quality of the bottom of the in-situ concrete technical problems need to be solved. The actual construction, using the first floor pouring, pouring and put mandrel side, while filling the segment construction methods. So that this problem has been solved. First full-length 19.16m setting a polystyrene foam core mold processing is 13, 12 of which 1.5m long, 1.16m long one, front and rear ends of the core mold processed into hollow cylinder with oblique angles. After the steel and external template system security complete, mandrel temporarily in place at one end of the hollow plate final pouring aside 2.0m long range roof bars, including steel mandrel positioning temporarily banding. Have a good lashing from one end of the top plate of steel pouring began pouring the first paragraph of the first floor of concrete, vibrating compaction and ensure the concrete surface to achieve the design thickness, manual removal of more concrete beyond the design elevation. After the vibration staff quit, aside from a position that puts people first mandrel by hand along the steel pan to locate the design position, to be precise after mandrel positioning, then began cutting the portion of the pouring side wall, roof and under paragraph concrete floor. It will be the second paragraph the standard concrete floor first two mandrel is pushed into the top tight first turn a mandrel pouring cycle. When casting to the last period of time, it will be reserved for the bottom section of the mandrel and then into concrete vibration compacting mandrel, and strengthening solid, final lashing roof bars, complete the remaining hollow concrete pouring. To control the speed and placement of concrete decking thickness to ensure the quality of concrete at the bottom of the mandrel, shop materials to meet the edge, the edge vibration requirements. Specifically the following measures taken by artificial feeding wheelbarrow, shovels assisted feeding, artificial iron rake decking manner under strict controls material thickness of no more than 20cm, a shop materials no longer than 50cm; requires quality staff dedicated service stare warehouse, vibrators staff must enter the hollow interior vibration, according to the longitudinal direction along the deck flat φ50 shaft vibrators, vibrators sequential order, to prevent leakage of vibration; the second layer of concrete when pouring, pay attention to both sides of the synchronized uniform cutting, strict control vibration time, non-vibrators pull material and excessive vibration to avoid offset and floating mandrel. For polystyrene foam core mold plate breakage translate within peeling dregs, after pouring through the end to end set aside to clean up mold bottom hole with the wind blowing in a timely manner. 3.3 situ prestressed hollow mandrel economic comparison transportation bridge PRECASTING polystyrene foam used in all material costs, and increased positioning reinforcement and processing fees of about 15,000 yuan, the use of material costs 1cm thickness of wood-based panels, It does not include lumber for purlin of more than 22,000 yuan. Compare mandrel reinforcement, demolition and other costs and the impact on the duration of the polystyrene foam is still very obvious advantages. 4 Conclusion polystyrene foam mandrel tube compared to traditional air capsule molding, shaping template, steel and wood combination template with light weight, easy to purchase, easy processing, low cost, simple operation, reduce the process and other significant advantages, especially for in a smaller number of hollow road bridge construction. Color bridge within Xinxiang Wanda mold factory is prestressed bridge with in-mold foam, Color Room, steel truss room, prestressed bridge with anchor plate, external wall insulation board and other professional production and processing company, has a complete, scientific quality management system. The company's integrity, strength and quality of products recognized by the industry. Welcome friends to visit, guidance and business negotiation. Our research and development with a polystyrene foam core templates bridge solves the problem of precast slab bridge capsule floating in inflatable roof thickness and technical problems, bridge hollow slab of polystyrene foam used in place of inflatable capsule, to ensure the accurate positioning within the mold and structure complete design size. Get the relevant experts and customer recognition and praise. Project: Henan Huai solid two standard high-speed civil, Henan Huai solid high-speed civil three standard, Henan Huai solid four-speed civil standard, Henan Huai solid civil six-speed standard, Henan Huai solid seven-speed civil standard, Henan Province, high-speed civil Deng three standard Henan Xichuan X110 line first precast plant, Xichuan X110 line third precast plant, Jing Hu set a new high-speed standard Pingdiquan mixing station, Beijing set a new high-speed standard Tuchengzi Hu a mixing station, Beijing set a new high-speed Hu 18 sets a standard mixing stations and other companies Sales Manager Zhao Tel: 1,870,373,531,513,937,394 068 Company Address: Xinxiang City store industrial zone company website: ww ww sjxcg com.