Lightweight Heat-Resistant Concrete for Fire Protection of Steel Building Constructions

ABSTRACT

One of the least fireproof building elements are steel bearing structures. For the majority of steels, temperature equal to 500°С is considered to be critical. At this temperature yield point of metal drops to the size of the running voltages invoked by the external loading and own mass of the structure. After reaching of this temperature, deformation of engineering structures and their almost instant destruction is observed. A brief description of fire protection the industrially used for structural steel construction has been presented. It is necessary to note, that at the same time there are no domestically produced materials of the 1st group of fireproofing, that can provide under the fire exposure up to 1100°С a thermal protection of bearing metal structures for 150 minutes [2]. Based on the abovementioned, development of effective fireproof coverings for steel structures of the 1-st fire resistance group with application of raw material resources of the country was applicable goal of the research. Justification of prospects of use of phosphatic сements based lightweight concrete as fireproof materials is given. The development of flame retardant was carried out on the basis of magnesiumammoniumphosphatic binder providing fast curing of composition. Spent periclase-chromite firebrick and ammophos were used as raw material to create a binder. At the first stage of work on the chosen raw material for the establishment of the optimum parity of the components of a phosphatic сement cold curing a number of structures have been investigated. As a function of structures optimization strength and adhesion properties were used. The maximum values of adhesion and compression strength is in the range of percentage composition of ammophos 40-50 wt.%. The general scheme of interaction in NH₄Н₂PO₄– (NH₄)₂НPO₄–MgO–Cr₂O₃–Н₂О have been investigated. It is established that under the interaction of magnesium oxide and ammoniumphosphatic binder mixed magnesiumphosphatic newformings are disengaged, struvite NH₄MgPO₄ 6H₂O is the most important of them. The thermochemical nature of processes is investigated. Developed effective material will solve the problem of fire protection of steel structures.

Keywords: light concrete, fire protection, steel construction structures, thermochemical transformations, phosphatic cements

For citation: Rumynskaya E., Kuzmenkov M. Lightweight Heat-Resistant Concrete for Fire Protection of Steel Building Constructions. Contemporary Issues of Concrete and Reinforced Concrete: Collected Research Papers. Minsk. Institute BelNIIS. Vol. 7. 2015. pp. 111-132.

References: 

1. Pozharnaya bezopasnost stroitelstva [Fire safety of construction]: G.I. Kasperov. Minsk : KII MChS Respubliki Belarus, 2007. 266 p. (rus)
2. Normy pozharnoy bezopasnosti Respubliki Belarus. Ognezashchitnye sredstva dlya stal’nykh konstruktsiy. Obshchie trebovaniya. Metody opredeleniya ognezashchitnoy effektivnosti [Standards of fire safety of Republic of Belarus. Fireproof means for steel structures. General requirements. Methods of determination of fireproof efficiency]. NPB 12 – 2000. Vved. 01.03.2000. Minsk: KII MChS Respubliki Belarus, 2000. 9 p. (rus)
3. Strakhov V., Garashchenko A. Construction materials. 2002. No 6. pp. 2–5. (rus)
4. Filimonov V. P. Fire and explosion safety. 2003. No 4. pp. 49–55. (rus)
5. Ivanova N. M. Construction materials. 1998. No 12. p. 12. (rus)
6. Pat. 2084476 Rossiyskaya Federatsiya. MPK C08L027/18 C08K013/02 C09K021/14 Ognezashchitnaya kompozitsiya dlya gibkikh elementov konstruktsiy [Fireproof composition for flexible elements of designs].A. Ya. Sartan; Yu. P. Bogdanova; V. E. Grushko ; V. I. Pashinin; I.A. Smirnova. Zayavl. 20.07.1997. Opubl. 10.03.1998. (rus)
7. Axel Kalleder, Non-flammable materials by nanotechnology. Proceedings of Conference “Fire Retardant Coatings III”, Axel Kalleder Berlin: Vincentz. pp. 77 – 85.
8. Sudakas L. G. Fosfatnye vyazhushchie sistemy [The phosphatic knitting systems]. Saint Petersburg : RIA «Kvintet», 2008. 260 p. (rus)
9. Yang Q., Zhu B. and Wu X. (2000). Materials and Structures. 2000. Vol. 33. рр. 229–234.
10. Phuong T. The effect of fillers on the properties of inorganic phosphate cement (IPC): master dissertation in partial fulfillment of the requirements for the Degree of Master of Science in Physical Land Resources, Thai lam Phuong, 2004. 106 р.
11. Ding, Zhu, Li, Zongjin (2005). ACI Materials Journal. 2005. рр. 45–46. 
12. Fei Qiao, Wei Lin, C.K. Chau and Zongjin Li. Key Engineering Materials. 2009. Vol. 400 – 402. рр. 115 – 120.
13. Bychek I. V. Tekhnologiya polucheniya fosfatnogo svyazuyushchego i zharostoykikh betonov kholodnogo otverzhdeniya iz khromsoderzhashchikh otkhodov [Tekhnology of receiving phosphatic binding and heat-resistant concrete of a cold setting from the chromecontaining waste]: the abstract of the thesis on competition of an academic degree of Cand.Tech.Sci. Minsk, 2004. 21 p. (rus)
14. Ammofos. Tehnicheskiye usloviya [Ammophos. Specifications] : GOST 18918–85. Vved. RB 17.12.92. Minsk : Belorus. gos. institut standartizacii i sertifikacii, 1992. 32 p. (rus)
15. Izdeliya ogneupornie i visokoogneupornie dlya futerovki vraschayuschihsya pechei. Tehnicheskie usloviya [Products fireresistant and high-fire-resistant for lining of the rotating furnaces. Specifications] : GOST 21436– 2004. Vved. 01.01.06. Minsk : Mejgos. sovet po standartizacii, metrologii i sertifikacii – Belorus. gos. institut standartizacii i sertifikacii, 2006. 15 p. (rus)
16. Vermikulit vspuchenny [Expanded vermiculite] : GOST 12865–67. Vved. 01.07.68. Moscow : Gos. komitet Sov. Min. SSSR po delam stroitelstva, 1968. 5 p. (rus).
17. Smesi rastvornye i rastvory stroitelnye. Tekhnicheskie usloviya [Mixes and mortar. Specifications] : STB 1307–2012. Vved. 01.01.13. Minsk : Gos. komitet po standartizacii RB, 2012. 26 p. (rus)
18. Konstant Z. A., Dindune A. P. Fosfaty dvukhvalentnykh metallov [Phosphates of bivalent metals]. Riga : Zinatne, 1987. 371 p. (rus)

ISSN 2076-6033