[1] Du Tao, Xie Nan, Jia Songsong,. Investigation and statistical analysis for variable materialloads on formwork system during construction [J]. Journal of Southeast University (English Edition), 2023, 39 (1): 17-25. [doi:10.3969/j.issn.1003-7985.2023.01.003]

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Investigation and statistical analysis for variable materialloads on formwork system during construction()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

39

Issue:

2023 1

Page:

17-25

Research Field:

Civil Engineering

Publishing date:

2023-03-20

Info

Title:

Investigation and statistical analysis for variable materialloads on formwork system during construction

Author(s):

Du Tao¹;  Xie Nan¹;  Jia Songsong²

¹ School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
² Tangshan Jiantou Real Estate Development Co., Ltd., Tangshan 063000, China

Keywords:

formwork system;  variable material loads;  random field;  influence surface;  equivalent uniformly distributed loads

PACS:

TU755.2;TU312

DOI:

10.3969/j.issn.1003-7985.2023.01.003

Abstract:

To accurately predict the variable material loads(VMLs)of concrete structures during construction, the equivalent uniformly distributed loads(EUDLs)are determined. The EUDL with the same load effects as the actual VML is produced on the shore. The VMLs of the reinforced concrete structure prior to and after concrete placement were investigated on-site and statistically analyzed. The statistical characteristics of the VML were obtained. The VML before and after concrete placements was randomly modeled to derive its spatial correlation. The finite element model of the formwork system was established. The characteristics of the influence surface for the shore axial force were analyzed using the maneuver method. Then, a random load was applied on the form surface. The EUDLs with the same load effects as the actual VML were calculated. By taking the standard value of a load, the recommended value of the VML prior to concrete placement is finally proposed. The results show that the VMLs surveyed at different construction sites vary greatly. With the increase in distance, the correlation coefficient of the random field zero-mean load gradually decreases. The recommended value of VMLs can be used to provide a reliable basis for the design and safety control of formwork systems.

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Memo

Memo:

Biographies: Du Tao(1990—), male, Ph.D. candidate; Xie Nan(corresponding author), female, doctor, professor, n_xie@ sina.com.
Foundation item: The National Natural Science Foundation of China(No. 51578050).
Citation: Du Tao, Xie Nan, Jia Songsong. Investigation and statistical analysis for variable material loads on formwork system during construction[J].Journal of Southeast University(English Edition), 2023, 39(1):17-25.DOI:10.3969/j.issn.1003-7985.2023.01.003.

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