[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(
)
施工期模板支架体系可变材料荷载的调查与统计分析
)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
- 施工期模板支架体系可变材料荷载的调查与统计分析
- 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.
- 为了准确预测施工期间混凝土结构的可变材料荷载(VML), 在立杆中产生与实际VML相同荷载效应的等效均布荷载(EUDL).对混凝土浇筑前后钢筋混凝土结构的VML进行现场调查和统计分析, 得到其统计特征, 并进行随机建模, 推导出其空间相关性, 建立了模板系统的有限元模型.利用机动法分析立杆轴力影响面的特点, 对模板面施加随机荷载, 计算出与实际VML具有相同荷载效应的EUDL.基于一般情况下荷载标准值的取值方法, 得到混凝土浇筑前VML的建议取值.结果表明:在不同施工现场所调研的VML差异较大;随着距离的增加, 随机场零均值荷载的相关系数逐渐减小;VML的推荐值可为模板支架体系的设计和安全控制提供可靠依据.
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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.