Wang Siqi, Feng Zhongju, Guo Conglin, Wei Jie, Zhao Ruixin
Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang'an University, Xi'an, 710064, China.
School of Highway, Chang'an University, Xi'an, 710064, China.
Sci Rep. 2024 Aug 14;14(1):18844. doi: 10.1038/s41598-024-69893-4.
In China, several expressways have been designed as prefabricated box culverts with hinge connections, which have different structural features from the prefabricated culverts in other countries. The difference would contribute to the culvert-soil interaction of prefabricated box culverts, which could affect the earth pressure on the culvert. Based on the field test and numerical simulation method, a hinged prefabricated box culvert (HPBC) with a span of 4 m and a rise of 4 m was investigated, which was applied to the Xi-Yu expressway in China. The objective of this research was to investigate the vertical earth pressure on the top slab of the HPBC culvert at different backfill heights through the field tests. The FLAC3D software was employed to conduct further analysis of the effects of backfill height, backfill modulus, and foundation modulus on the vertical earth pressure on the top slab of HPBC. The differences between the HPBC and monolithic box culvert (MBC) were also examined. Furthermore, a revised method for calculating the vertical earth pressure on the top slab was put proposed and compared with the AASHTO method for calculating earth pressure on the top of culverts and the values taken from the Chinese culvert design code. The proposed method is capable of improving the accuracy of the earth pressure approach, making it more representative of actual conditions. Subsequently, the sensitivity analysis of backfill height, backfill modulus and foundation modulus to the vertical earth pressure concentration coefficient of the top slab was carried out by using the principle of orthogonal array analysis and the modified calculation method proposed in this paper. The findings of this study offer valuable insights into the determination of culvert top earth pressure of HPBC.
在中国，多条高速公路已设计为采用铰接连接的预制箱涵，其结构特征与其他国家的预制涵管有所不同。这种差异会影响预制箱涵与土壤的相互作用，进而可能影响涵管上的土压力。基于现场试验和数值模拟方法，对一座跨度为4米、矢高为4米的铰接预制箱涵（HPBC）进行了研究，该箱涵应用于中国的西渝高速公路。本研究的目的是通过现场试验，研究不同回填高度下HPBC涵管顶板上的垂直土压力。采用FLAC3D软件进一步分析回填高度、回填模量和地基模量对HPBC顶板垂直土压力的影响。还研究了HPBC与整体式箱涵（MBC）之间的差异。此外，提出了一种计算顶板垂直土压力的修正方法，并与美国公路与运输官员协会（AASHTO）计算涵管顶部土压力的方法以及中国涵管设计规范中的取值进行了比较。所提出的方法能够提高土压力计算方法的准确性，使其更能代表实际情况。随后，利用正交阵列分析原理和本文提出的修正计算方法，对回填高度、回填模量和地基模量对顶板垂直土压力集中系数的敏感性进行了分析。本研究结果为HPBC涵管顶部土压力的确定提供了有价值的见解。
