Investigation of geopolymer-based ultra-high performance concrete slabs against contact explosions
Investigation of geopolymer-based ultra-high performance concrete slabs against contact explosions
复制标题
地质聚合物基超高性能混凝土板抗接触爆炸的研究
DOI：
10.1016/j.conbuildmat.2021.125727
复制
发表时间：
2021-12-28
影响因子：
7.4
通讯作者：
Su, Yu
中科院分区：
文献类型：
--
作者：
Liu, Jian;Peng, Yun;Su, Yu
地质聚合物基超高性能混凝土（G-UHPC）是UHPC的一种新形式，是为满足超高强度、经济高效和环境友好的建筑材料的需求而开发的。本文初步研究了纤维增强G-UHPC板在接触爆炸作用下的局部损伤情况。在 0.4 kg TNT 下，对三块 150 mm 厚的板进行了测试，其中包括一块由钢筋增强普通强度混凝土 (NSC) 制成的对照样本和两块 G-UHPC 板，即普通 G-UHPC 和 1.5% 钢纤维增强 G-UHPC。在 1.0 kg TNT 下，对两块 200 毫米厚的板进行了测试，其中包括一块由钢筋增强 NSC 制成的对照样本和一块 2% 玄武岩纤维增强 G-UHPC 板。与钢筋增强 NSC 相比，普通和 2% 玄武岩纤维增强 G-UHPC 由于其自身的脆性特性，性能较差，而 1.5% 钢纤维增强 G-UHPC 却具有优异的性能。此外，还对钢筋增强 NSC 板和 1.5% 钢纤维增强 GUHPC 板进行了数值研究，通过显式有限元代码 LS-DYNA 再现了接触爆炸引起的局部损伤。利用经过验证的数值模型，进行参数化研究，探讨接触爆炸下板厚和TNT装药重量对1.5%钢纤维增强G-UHPC板局部损伤的影响，并通过支持向量机（SVM）方法对局部损伤进行识别和分类。基于机器学习结果，导出了经验方程，用于快速评估接触爆炸下 1.5% 钢纤维增强 G-UHPC 板的局部损伤水平。
Geopolymer-based ultra-high performance concrete (G-UHPC) is a new form of UHPC, which has been developed to meet the demand for ultra-high strength, cost-effective and eco-friendly construction materials. This paper preliminarily investigated local damage of fibre reinforced G-UHPC slabs subjected to contact explosions. Under 0.4 kg TNT, three 150 mm thick slabs including one control specimen made of steel rebar reinforced normal strength concrete (NSC) and two G-UHPC slabs, i.e. plain G-UHPC and 1.5% steel fibre reinforced G-UHPC, were tested. Under 1.0 kg TNT, two 200 mm thick slabs including one control specimen made of steel rebar reinforced NSC and one 2% basalt fibre reinforced G-UHPC slab were tested. Comparing with steel rebar reinforced NSC, inferior performance of plain and 2% basalt fibre reinforced G-UHPCs was observed owing to their own brittle characteristics, whereas superior performance of 1.5% steel fibre reinforced G-UHPC was achieved. Further, numerical investigations were conducted on the steel rebar reinforced NSC and 1.5% steel fibre reinforced GUHPC slabs to reproduce their local damage induced by contact explosions through the explicit finite element code LS-DYNA. With the validated numerical model, parametric studies were performed to explore the effect of slab thickness and TNT charge weight on the local damage of 1.5% steel fibre reinforced G-UHPC slabs under contact explosions, and then the local damages were identified and classified via the support vector machine (SVM) method. Based on the machine learning results, empirical equations were derived for the fast assessment of local damage levels of 1.5% steel fibre reinforced G-UHPC slabs under contact explosions.