- BUILDING STRUCTURES, BUILDINGS AND FACILITIES
- Stress-Strain State Of Reinforced Concrete Beams When Changing The Force Sign
- UDC 624.072.2:699.841
doi: 10.33622/0869-7019.2023.02.44-52
Sofia O. KURNAVINA, kurnavinaso@mgsu.ru
Ilya V. TSATSULIN, ilya.vladimirovich.t@mail.ru
Moscow State University of Civil Engineering (National Research University), Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. In domestic regulatory documents on earthquake-resistant construction, the development of plastic deformations in structures under seismic influence is assumed. Their presence has a significant effect on the stress-strain state and bearing capacity of reinforced concrete elements when changing the force sign. This fact is neglected in the current regulatory documents. The results of experimental research of behavior of reinforced beams when changing the force sign are represented. Seven series of identical samples were tested. The samples of the first series were loaded by two monotonously increasing forces up to destruction. They were considered as reference The samples of the rest series were tested by two semi cycles of loading. In the first semi cycle the specimens were loaded until the specified coefficient of plasticity was reached. Then they were turned over and loaded according to the same scheme with a load of the opposite sign until destruction. The influence of plastic deformations of reinforcement on the stress-strain state of bent reinforced concrete elements under monotonous loading and change of the force sign was studied. Based on the results of the experiment, it was concluded that the strain diagrams along the height of the section can be approximated by a bilinear dependence both under monotonic loading and unloading. The nature of the dependence changes during loading. It is established that the maximum plastic deformations in the first half-cycle of loading significantly affect the stress-strain state, bearing capacity and the mechanism of destruction of beams when changing the sign of force. In this regard, there is a need to limit the maximum plastic deformations in seismic calculations of reinforced concrete structures.
Keywords: alternating effects, plastic deformations, through cracks, stress-strain state, hypothesis of bilinear sections - REFERENCES
1. Ayzenberg Ja. M. Some lessons of earthquake in Armenia on December 7 1988. Stroitel'stvo i arkhitektura. Ekspress-informatsiya. Seriya Seysmostoykoe stroitel'stvo. Moscow, VNIIIS Publ., 1992, iss. 2, pp. 2-7. (In Russ.).
2. Zhunusov Ò. Zh. Zemletryasenie i seysmostoykoe stroitel'stvo [Earthquake and earthquake-resistant construction]. Almaty, LEM Publ., 2008. 76 p. (In Russ.).
3. Kilimnik L. Sh. Structural damage in severe earthquakes. Beton i zhelezobeton, 1979, no. 11, pp. 11-13. (In Russ.).
4. Mkrtychev O. V., Dzhinchvelashvili G. A., Busalova M. S. Modeling of the interaction of the structure with the base when calculating for earthquakes. Vestnik MGSU, 2013, no.12, pp. 34-40. (In Russ.).
5. Mkrtychev O. V., Reshetov A. A. A representative set of earthquake accelerograms for calculating buildings and structures for seismic impacts. Vestnik MGSU, 2017, vol. 12, no. 7(106), pp. 754-760. (In Russ.). doi: 10.22227/1997-0935.2017.7.754-760
6. Abakanov M. S. Malotsiklovaya prochnost' zhelezobetonnykh konstruktsiy karkasnykh zdaniy pri deystvii nagruzok tipa seysmicheskikh [Low-cycle strength of reinforced concrete structures of frame buildings under the action of seismic loads]. Almaty, KazNIISA Publ., 2016. 132 p. (In Russ.).
7. Abakanov M. S. Strength of reinforced concrete constructions under action of low-cycle loads like seismic. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 2013, no. 5, pp. 30-34. (In Russ.).
8. Kabantsev O. V., Useinov E. S., Sharipov Sh. Determination of allw coefficient of permissible damage to earthquake-resistant structures. Vestnik TGASU, 2016, no. 2(55), pp. 117-129. (In Russ.).
9. Zharnitsky V. I., Golda Yu. L., Kurnavina S. O. Damage development process in reinforced concrete frame unader the action if seismic loads. Proceedings of the III All-Russian (II International) Conference on concrete and reinforced concrete "Concrete and reinforced concrete - glance at future". Moscow, MGSU Publ., 2017, vol. 2, pp. 57-67. (In Russ.).
10. Kurnavina S. O., Tsatsulin I. V. The influence of open cracks in compressed area of concrete on behaviour of bending elements of frame buildings under special alternating loads. Journal of Physics: Conference Series: International scientific conference on modelling and methods of structural analysis, MMSA 2019. Moscow, Institute of Physics Publ., 2020, pp. 012037. doi: 10.1088/1742-6596/1425/1/012037
11. Kalkan E., Kunnath S. K. Method of modal combinations for pushover analysis of buildings. 13th World conference on earthquake engineering, Vancuever, B. C. Canada, 2004, paper no. 2713.
12. Sofyan J. A. Seismic evaluation of reinforced concrete frames using pushover analysis. Al-Rafidian Engineering Journal, 2013, vol. 21, no. 3, pp. 28-45.
13. Ayzenberg Ja. M. Spitak earthquake on December 7, 1988. Some lessons and conclusions. Seysmostoykoe stroitel'stvo. Bezopasnost' sooruzheniy, 1999, no. 1, pp. 6-9. (In Russ.).
14. Kabantsev Î. V. Macroseismic effect of earthquake on October 4 1994 on the islands of Iturup, Kunashir, Shikotan. Seysmostoykoe stroitel'stvo. Ekspress-informatsiya. Seriya 14. Stroitel'stvo v osobykh usloviyakh. Moscow, VNIIIS Publ., iss. 4, 1995, pp. 7-11. (In Russ.).
15. Rootman Ju. L, Simbort E. Selection of seismic loads reduction coefficient on a basis of analysis of the plastic resource of the structure. Vestnik grazhdanskikh inzhenerov, 2011, no. 2(27), pp. 78-81. (In Russ.).
16. Eryshev V. À. Method for calculating deformations of reinforced concrete core and slab structures under repeated, alternating and other types of complex loading. Moscow, 1997, Available at: https://search.rsl.ru/ru/record/01000199724 (accessed 02.11.2022). (In Russ.).
17. Karpenko N. I., Eryshev V. À., Mukchamediev Ò. À. Investigation of deformations of reinforced concrete beam elements under alternating loads. Issledovanie zhelezobetonnykh konstruktsiy pri staticheskikh povtornykh i dinamicheskikh vozdeystviyakh [Investigation of reinforced concrete structures under static repeated and dynamic impacts]. Ìoscow, NIIZHB Publ.,1984, pp. 55-72. (In Russ.).
18. Zharnitsky V. I., Kurnavina S. O. Enegry method for determining the direction of cracks in reinforced concrete beams. Izvestiya vysshikh uchebnykh zavedeniy. Tekhnologiya tekstil'noy promyshlennosti, 2018, no. 5, pp. 213-216. (In Russ.).
19. Krylov À. Ñ. Strength of reinforced concrete beams with rigid reinforcement made of high-strength concrete. Moscow, Research Center of Construction Publ., 2019. Available at: https://search.rsl.ru/ru/record/01010169304 (accessed 16.10.2022). (In Russ.).
20. Zharnitsky V. I., Belikov A. A, Kurnavina S. O. Experimental study of resistance of reinforced concrete beams to the shear force. Promyshlennoe i grazhdanskoe stroitel'stvo, 2011, no. 3, pp. 18-20. (In Russ.).
21. Kurnavina S. O., Tsatsulin I. V. Influence of open cracks in the compressed zone of concrete on the bearing capacity of bent reinforced concrete elements. Stroitel'stvo i rekonstruktsiya, 2021, no. 2(94), pp. 28-38. (In Russ.). doi: 10.33979/2073-7416-2021-94-2-28-38 - For citation: Kurnavina S. O., Tsatsulin I. V. Stress-strain State of Reinforced Concrete Beams When Changing the Force Sign. Promyshlennoe i grazhdanskoe stroitel'stvo [Industrial and Civil Engineering], 2023, no. 2, pp. 44-52. (In Russ.). doi: 10.33622/0869-7019.2023.02.44-52
BACK