Nonlinear Analysis of the Static Performance of Double-Chamber U-Shaped Assembled Utility Tunnel Under Circumferential Loading
-
摘要: 将上下2个预制槽型构件在施工现场通过张拉预应力筋连接成整体,即形成了预制槽型拼装综合管廊。该管廊具有运输安装便捷、工期短、对环境影响小等特点。基于商用软件ABAQUS,建立了槽型拼装综合管廊模型,通过前期完成的单舱槽型拼装综合管廊环向加载试验,验证了模型的合理性。基于该模型,开展了环向加载模式下(模拟土压和顶部过载)双舱综合管廊受力全过程的非线性分析。研究参数包括:现浇/预制管廊、侧向土压力系数(0.55,0.65,0.75)和预应力筋有效预应力(400,500,600 MPa)。有限元分析表明:与现浇管廊不同,预制管廊的塑性铰首先出现在顶底板跨中,随后出现在顶底板与中壁交界处,最后在侧壁拼缝处出铰而导致结构破坏;预制管廊的承载力和延性均高于相应的现浇管廊(承载力和延性分别高2%和33%);相较于侧向土压力系数为0.55的管廊,侧向土压力系数为0.65和0.75的管廊承载力分别提高了6.4%和11.75%,而延性则降低了2.3%和18.6%;预应力筋有效预应力的大小对管廊承载力和延性的影响均很小。双舱预制槽型拼装综合管廊具有较高的承载力和良好的延性,工程应用前景广阔。Abstract: The upper and lower prefabricated U-shaped components are connected by prestressed tendons at the construction site to form a prefabricated U-shaped assembled utility tunnel. This type of tunnel offers convenient transportation and installation, a short construction period, and minimal environmental impact. A finite element model of the U-shaped assembled utility tunnel was established using the commercial software ABAQUS, and its validity was verified through a circumferential loading test on a single-chamber U-shaped assembled utility tunnel conducted in an earlier study. Based on this model, a nonlinear analysis of the entire loading process of a double-chamber utility tunnel under circumferential loading (simulating earth pressure and top overload) was carried out. The parameters investigated included: utility tunnel type (cast-in-place vs. prefabricated), lateral earth pressure coefficient (0.55, 0.65, and 0.75), and effective prestress of the prestressed tendons (400, 500, and 600 MPa). The finite element analysis showed that, unlike cast-in-place utility tunnels, plastic hinges in prefabricated tunnels first appeared at the mid-span of the top and bottom slabs, then at the junctions between the slabs and the middle wall, and finally at the joints of the side walls, leading to structural failure. The bearing capacity and ductility of prefabricated tunnels were higher than those of cast-in-place tunnels (by 2% and 33%, respectively). Compared to the tunnel with a lateral earth pressure coefficient of 0.55, the bearing capacity of tunnels with coefficients of 0.65 and 0.75 increased by 6.4% and 11.75%, respectively, while ductility decreased by 2.3% and 18.6%. The effective prestress level of the prestressed tendons had little effect on the bearing capacity and ductility of the tunnel. Overall, the double-chamber prefabricated U-shaped assembled utility tunnel has high bearing capacity and good ductility, offering broad prospects for engineering applications.
-
[1] XUE W C,CHEN S Y,SONG Z. Pseudo-static tests on full-scale hybrid precast utility tunnel composed of double-skin sidewalls and cast-in-place bottom slab[J]. Structures,2023,58:105573. [2] XUE W C,CHEN S Y,WANG Q H. Cyclic loading test conducted on the bottom joints of a hybrid precast utility tunnel composed of double-skin sidewalls and a precast bottom slab[J]. Buildings,2024,14(2):341. [3] 薛伟辰,王恒栋,油新华,等. 我国预制拼装综合管廊结构体系发展现状与展望[J]. 施工技术,2018,47(12):6-9. [4] 陈盛扬,胡翔,薛伟辰. 预制槽型拼装混凝土综合管廊整体结构受力性能分析[J]. 特种结构,2021,38(3):28-32. [5] 胡翔. 预制预应力综合管沟结构性能、设计与施工关键技术研究[D]. 上海:同济大学,2007. [6] 胡翔,薛伟辰. 预制预应力综合管廊受力性能试验研究[J]. 土木工程学报,2010,43(5):29-37. [7] 薛伟辰,康明睿. 单舱槽型拼装混凝土综合管廊抗震性能试验研究报告[R]. 上海:同济大学,2015. [8] 薛伟辰,王庆华. 双舱槽型拼装混凝土综合管廊抗震性能试验研究报告[R]. 上海:同济大学,2020. [9] 中华人民共和国住房和城乡建设部. 城市综合管廊工程技术规范:GB/T 50838—2015[S]. 北京:中国计划出版社,2015. [10] 日本土木学会隧道工学委员会. 隧道标准规范(盾构篇)及解说[M]. 朱伟,译. 北京:中国建筑工业出版社,2001. -
点击查看大图
计量
- 文章访问数: 19
- HTML全文浏览量: 6
- PDF下载量: 0
- 被引次数: 0
登录
注册
E-alert
登录
注册
E-alert
下载: