STRESS-STRAIN STATE OF PREFABRICATED MONOLITHIC BENDING ELEMENT AT GRADUAL INSTALLATION AND LOADING

The stress-strain state of the prefabricated monolithic element depends on its gradual installation and loading. Regulatory documents of the Russian Federation indicate the need to calculate precast-monolithic structures for two stages of construction: before and after the specified monolithic concrete strength acquired. In this case, the stress-strain state that appeared in the prefabricated elements before the specified monolithic concrete strength should be considered.  However, the construction and loading stages at issue and accumulation of stresses and strains are not disclosed in the regulatory documents. In addition, this problem is insufficiently studied.  In this regard, the aim of this paper is to study the pre-loading effect of the prefabricated element on its stress-strain state and the load-bearing capacity.  During the experiments, a pre-loaded prefabricated part is studied. The obtained results are compared with instantaneously loaded test samples. Other parameters of the experimental models are completely identical. In all, 5 samples are tested (step-by-step loading of 3 samples and instantaneous loading of 2 samples).  It is shown that pre-loading of the preloaded prefabricated part significantly affects the stress-strain state of the whole structure and its total load-bearing capacity.  

1. Teplova Zh.S., Vinogradova N.A. Sborno-monolitnye perekrytiya sistemy «MARKO» [Prefabricated monolithic floors of the MARCO system]. Stroitel'stvo unikal'nykh zdanii. 2015. No. 8. Pp. 48–59. (rus)

2. Klyueva N.V., Kolchunov V.I., Rypakov D.A., Bukhtiyarova A.S. Prochnost' i deformativnost' sborno-monolitnykh karkasov zhilykh zdanii ponizhennoi materialoemkosti pri zaproektnykh vozdeistviyakh [Strength and deformability of prefabricated monolithic frames of residential buildings of reduced material consumption for beyond-design impacts]. Promyshlennoe i grazhdanskoe stroitel'stvo. 2015. No. 1. Pp. 5–9. (rus)

3. Povetkin M.S. Napryazhenno-deformirovannoe sostoyanie usilennykh pod nagruzkoi zhelezo-betonnykh izgibaemykh prednapryazhennykh elementov: dis. … kand. tekhn. nauk [Stress-strain state of reinforced concrete bent prestressed elements reinforced under load. PhD Thesis]. Kursk, 2009. 187 p. (rus)

4. Nikonorov R.M. Sovmestnaya soprotivlyaemost', deformativnost' zhelezobetonnykh elementov perekrytiya sborno-monolitnykh karkasov s ploskimi plitami i skrytymi rigelyami: dis. … kand. tekhn. nauk [Joint resistance, deformability of reinforced concrete elements of overlapping precast-monolithic frames with flat plates and hidden crossbars]. Moscow, 2008. 219 p. (rus)

5. Parashchenko N.A., Gorshkov A.S., Vatin N.I. Chastichno-rebristye sborno-monolitnye perekrytiya s yacheistobetonnymi blokami [Partially ribbed precast-monolithic floors with cellular concrete blocks]. Inzhenerno-stroitel'nyi zhurnal. 2011. No. 6. Pp. 50–55. (rus)

6. Chepurnenko A.S. Stress-strain state of three-layered shallow shells under conditions of non-linear creep. Magazine of Civil Engineering. 2017. V. 8 (74). Pp. 156–168.

7. Medvedev V.N., Semenyuk S.D. Prochnost' i deformativnost' balochnykh izgibaemykh elementov s vneshnim listovym armirovaniem [Strength and deformability of bending elements with external steel reinforcement]. Inzhenerno-stroitel'nyi zhurnal. 2016. No. 3(63). Pp. 3–15. (rus)

8. Drakatos I.S., Muttoni A., Beyer K. Internal slab-column connections under monotonic and cyclic im-posed rotations. Engineering Structures. 2016. V. 123. Pp. 501–516.

9. Koyankin A.A., Mitasov V.M. Stress-strain state of precast and cast-in place building. Maga-zine of Civil Engineering. 2017. V. 6 (74). Pp. 175–184.

10. Shalennyi V.T., Papernyk R.B. Povyshenie tekhnologichnosti proektnykh reshenii monolitnykh i sborno-monolitnykh zdanii i sooruzhenii [Improving manufacturability of design solutions for monolithic and precast monolithic buildings]. Promyshlennoe i grazhdanskoe stroitel'stvo. 2010. No. 2. Pp. 19–21. (rus)

11. Shembakov V.A. Sborno-monolitnoe karkasnoe domostroenie. Rukovodstvo k prinyatiyu resheniya [Prefabricated monolithic frame housing construction. Decision making guide]. Chebo-ksary: Cheboksarskaya tipografiya, 2005. 119 p. (rus)

12. Koyankin A.A., Mitasov V.M. Nekotorye rezul'taty naturnykh ispytanii fragmenta karkasnogo zdaniya v sborno-monolitnom ispolnenii [Some results of full-scale tests of frame building in precast-monolithic design]. Beton i zhelezobeton. 2015. No. 5. Pp. 18–20. (rus)

13. Semchenkov A.S., Khavkin A.K., Sokolov B.S. Ispytanie naturnogo fragmenta karkasa «RADIUSS» s primeneniem kruglopustotnykh plit [Testing natural fragment of the RADIUSS framework using round hollow slabs]. Beton i zhelezobeton. 2008. No. 6. Pp. 2–5. (rus)

14. Qian K., Li B. Resilience of flat slab structures in different phases of progressive collapse. ACI Structural Journal. 2016. V. 113. Pp. 537–548.

15. Koyankin A.A. Oblegchennoe sborno-monolitnoe perekrytie [Lightweight prefabricated monolithic ceiling]. Vestnik MGSU. 2017. No. 6 (105). Pp. 636–641. (rus)

16. Koyankin A.A., Mitasov V.M. Ispytaniya sborno-monolitnogo perekrytiya na stroyashchemsya zhilom dome [Tests of precast-monolithic floors on a residential building under construction]. Beton i zhelezobeton. 2016. No. 3. Pp. 20–22 (rus)