摘要
隧道减震层为提升高烈度地震区隧道抗震性能的重要措施,减震层的材料性能是影响隧道减震效果重要因素。为探究一种适合隧道减震层的聚丙烯泡沫混凝土,并对其制备工艺及力学吸能特性进行分析。基于聚丙烯泡沫体积含量指标,采用代石法配制了多种体积含量的聚丙烯泡沫混凝土,通过试验探明了表观密度、抗压强度、弹性模量、泊松比、静动态吸能特性等随聚丙烯泡沫体积含量的变化规律。研究成果表明:(1)当发泡聚丙烯(EPP)体积含量从0增加至28%时,表观密度为2331~1451 kg/m3,抗压强度为54.5~11.2 MPa,抗拉强度为3.6~1.6 MPa,弹性模量为34.0~16.0 GPa,泊松比为0.19~0.28,建立了物理力学性能与EPP体积含量关系表达式;(2)随着EPP体积含量的增加,混凝土静态吸能呈现先增大再减小后增大的趋势,当EPP体积含量为11%时,静态吸能效果最好;(3)随着EPP体积含量的增加,混凝土动态吸能呈现逐渐增大的趋势,当EPP体积含量为28%时,动态冲击吸能效果最好。研究成果可为聚丙烯泡沫混凝土作为减震吸能材料应用提供理论依据。
Tunnel damping layer is an important measure to improve the seismic performance of tunnels in high-intensity earthquake areas.The material performance of damping layer is an important factor affecting the damping effect of tunnels.In order to explore a polypropylene foam concrete suitable for tunnel damping layer,its preparation process and mechanical energy absorption characteristics were analyzed.Based on the volume content index of polypropylene foam,a variety of volume content of polypropylene foam concrete was prepared by substitution stone method.The changes of apparent density,compressive strength,elastic modulus,Poisson′s ratio,static and dynamic energy absorption characteristics with the volume content of polypropylene foam were verified by experiments.The results show that when the volume content of expanded polypropylene(EPP)increases from 0 to 28%,the apparent density is from 2331 kg/m3 to 1451 kg/m3,the compressive strength is from 54.5 MPa to 11.2 MPa,the tensile strength is from 3.6 MPa to 1.6 MPa,the elastic modulus is from 34.0 GPa to 16.0 GPa,and the Poisson′s ratio is from 0.19 to 0.28.The relationship between the physical and mechanical properties and the volume content of EPP is established.With the increase of EPP volume content,the static energy absorption of concrete increases first and then decreases and then increases.When the EPP volume content is 11%,the static energy absorption effect is the best.With the increase of EPP volume content,the dynamic energy absorption of concrete gradually increases.When the EPP volume content is 28%,the dynamic impact energy absorption effect is the best.The research results can provide theoretical basis for the application of polypropylene foam concrete as energy absorption material.
作者
路军富
肖钦文
谭进义
陈龙
LU Junfu;XIAO Qinwen;TAN Jinyi;CHEN Long(State Key Laboratory of Geological Disaster Prevention and Protection of Geological Environment,Chengdu University of Technology,Chengdu 610059,China;Ji′an College,Ji′an 343000,China;China Southwest Geotechnical Investigation and Design Institute Co.,Ltd.,Chengdu 610052,China)
出处
《混凝土》
CAS
北大核心
2024年第2期24-29,共6页
Concrete
基金
国家自然科学基金面上项目(51978088)
SKLGP国家重点实验室自主课题(SKLGP2021Z007)。
关键词
隧道减震层
聚丙烯泡沫混凝土
物理力学性能
吸能特性
tunnel damping layer
polypropylene foam concrete
physical and mechanical properties
energy absorption characteristics
