摘要
超高性能混凝土(Ultra-high performance concrete,UHPC)是一种具有超高强度、超高韧性、超高抗力和优异耐久性的新型水泥基复合材料。自从加拿大建成第一座超高性能混凝土步行桥之后,超高性能混凝土被广泛应用于桥梁工程中。随着我国大型基础设施领域的拓展和建设水平的提高,超高性能混凝土在超高层建筑、大跨桥梁、海上石油平台、核反应堆安全壳和军事防护工程的应用也越来越广泛。服役于桥梁工程、核电工程和军事工程的UHPC除了承受常规的荷载外,还常遭受撞击、振动、冲击、爆炸和弹体侵彻等动态冲击荷载。目前的研究表明,UHPC材料在动态冲击荷载作用下表现出与在常规静态和准静态作用下显著不同的效应。超高性能混凝土的动力学研究需解决两大难题:(1)高应变率试验条件与装置--动态力学性能的研究与应变率相关,应变率越高,所需要的试验条件越苛刻;(2)动态冲击本构模型--对于实施难度大或经费要求高的试验,数值模拟是非常有益的辅助手段,但强荷载冲击混凝土材料的过程非常剧烈,要考虑的耦合因素也很多,因此准确选用模型成了数值模拟的一大难题。近几年,为了满足UHPC动力学性能试验的要求,研究人员在传统动力学试验设备的基础上发展了适用应变率范围更广,加载方式更全面的新型动力学试验设备。此类新型设备不仅为UHPC的动力学试验提供了更广泛的试验范围,更保证了动力学试验的准确性。在理论研究方面,研究者通过大型试验得到了UHPC的动态本构模型,并结合LS-DYNA软件对冲击、爆炸过程进行了数值模拟。这些数学模型将保证动力学仿真模拟的准确性,具有极大的参考价值。本文从研究动态性能试验设备和UHPC材料动态力学性能两个方面展开综述,动态性能试验设备主要包括液压机、落锤、霍普金森杆、侵彻系统、爆炸系统和其他试验系统六个方面,详细介绍了试验原理和设备的组成,并分析归纳了上述设备在UHPC动力学性能试验中的应用;UHPC动态力学性能包括冲击压缩、冲击拉伸、层裂、侵彻和爆炸五个方面,全面介绍了原材料、配合比、应变率等因素对各性能的影响及动力学性能的变化规律,以期为后期的UHPC动力学性能试验方法及试验结果分析提供参考思路。
Ultra-high performance concrete (UHPC) is a new type of cement matrix composite material with ultra-high strength,ultra-high toughness,ultra-high resistance and excellent durability.Since Canada has built the first ultra-high performance concrete pedestrian bridge,ultra-high performance concrete is increasingly used in bridge engineering.With the development of large-scale infrastructure and the improvement of construction level in China,ultra-high performance concrete will have more and more extensive application prospects in ultra-high-rise buildings,long-span bridges,offshore oil platforms,nuclear reactor containment shells and military protection projects.UHPC,which is used in bridge engineering,nuclear power engineering and military engineering,is often subjected to dynamic impact loads such as impact,vibration,impact,blast and projectile penetration in addition to conventional loads.The current research shows that UHPC materials show significantly different effects from conventional static and quasi-static materials under dynamic impact load. The dynamic research of ultra-high performance concrete needs to solve two major problems:(1) high strain rate test conditions and devi- ces - the research of dynamic mechanical properties is related to strain rate,the higher the strain rate,the more stringent the test conditions required;(2) dynamic impact constitutive model - numerical simulation is a very useful auxiliary means for the implementation of difficult or expensive tests.However,the process of strong load impacting concrete material is very intense,and there are many coupling factors to be considered,so the accurate selection of the model has become a major problem in numerical simulation. In recent years,in order to meet the requirements of UHPC dynamic performance test,researchers have developed a new type of dynamic test equipment with wider strain rate range and more comprehensive loading mode based on traditional dynamic test equipment.This new type of equipment not only provides a wider range of dynamic test for UHPC,but also guarantees the accuracy of dynamic test.In terms of theoretical research,researchers obtained the dynamic constitutive model of UHPC through large-scale experiments,and conducted numerical simulation of the impact and explosion process by combining LS-DYNA software.These mathematical models will guarantee the accuracy of dynamic simulation and have great reference value. This paper studies the dynamic performance test equipment and materials UHPC dynamic mechanical performance were reviewed in two aspects,the dynamic performance test equipment mainly includes hydraulic press,drop hammer,Hopkinson bar,penetration test system,explosion and other test system in six aspects,the system introduces the test principle and equipment composition,analysis,it concludes the equipment in the application of dynamic performance test of UHPC.The dynamic mechanical properties of UHPC include impact compression,impact tensile,laminar fracture,penetration and explosion.The influences of raw materials,mix ratio,strain rate and other factors on various properties and the changing laws of dynamic properties are comprehensively introduced.It is expected that this paper can provide reference ideas for future UHPC dynamic performance test methods and test results analysis.
作者
张文华
刘鹏宇
吕毓静
ZHANG Wenhua;LIU Pengyu;LYU Yujing(Department of Civil Engineering,Nanjing Forestry University,Nanjing 210037;Jiangsu Research Institute of Building Science,Nanjing 210008)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2019年第19期3257-3271,共15页
Materials Reports
基金
国家自然科学基金面上项目(51678309)
江苏省自然科学基金面上项目(BK20161529)
中国博士后基金面上项目(2016M600351)
江苏省博士后基金面上项目(1601028B)
江苏高校优势学科建设工程资助项目(PAPD)~~
作者简介
张文华,南京林业大学土木工程学院,建筑工程系,副教授,硕士生导师。2013年毕业于东南大学,获工学博士学位。现为中国硅酸盐学会固废分会青年委员会委员,RILEM(国际材料与结构研究实验联合会)会员,国际期刊 Construction and Building Materials,Science and Engineering of Composites Materials 审稿人。主要研究方向为超高性能混凝土动态力学行为。zhangwenhua2009@163.com.
