土木工程与管理学报
土木工程與管理學報
토목공정여관이학보
JOURNAL OF HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY·URBAN SCIENCE
2015年
3期
40-43
,共4页
陈学强%彭刚%梁辉%田为
陳學彊%彭剛%樑輝%田為
진학강%팽강%량휘%전위
循环加卸载%动态力学特性%混凝土%抗压强度%应力-应变全曲线
循環加卸載%動態力學特性%混凝土%抗壓彊度%應力-應變全麯線
순배가사재%동태역학특성%혼응토%항압강도%응력-응변전곡선
cyclic loading and unloading%dynamic mechanical properties%concrete%compressive strength%stress-strain curve
进行了不同侧压力(0、80、230、390 kN)、不同应变速率(10-2/s、10-3/s、10-4/s、10-5/s)下,混凝土的轴向循环加卸载压缩试验,研究了循环加卸载下,混凝土在不同应变速率和侧压下的动态力学特性变化规律。结果表明:随着侧压的增加,混凝土抗压强度的率敏感性降低;混凝土的峰值应变随应变速率的增大总体呈现减小的趋势,且随着侧压的增大,峰值应变逐渐增大。随着应变速率的增加,混凝土循环加卸载应力–应变全曲线所经历的循环次数逐渐减小,且全曲线外包络线上升段形状愈来愈“陡”。当应变速率一定时,随着侧应力的增大,峰值应力以前循环次数不断增多,即侧应力延缓了损失,推迟了破坏。
進行瞭不同側壓力(0、80、230、390 kN)、不同應變速率(10-2/s、10-3/s、10-4/s、10-5/s)下,混凝土的軸嚮循環加卸載壓縮試驗,研究瞭循環加卸載下,混凝土在不同應變速率和側壓下的動態力學特性變化規律。結果錶明:隨著側壓的增加,混凝土抗壓彊度的率敏感性降低;混凝土的峰值應變隨應變速率的增大總體呈現減小的趨勢,且隨著側壓的增大,峰值應變逐漸增大。隨著應變速率的增加,混凝土循環加卸載應力–應變全麯線所經歷的循環次數逐漸減小,且全麯線外包絡線上升段形狀愈來愈“陡”。噹應變速率一定時,隨著側應力的增大,峰值應力以前循環次數不斷增多,即側應力延緩瞭損失,推遲瞭破壞。
진행료불동측압력(0、80、230、390 kN)、불동응변속솔(10-2/s、10-3/s、10-4/s、10-5/s)하,혼응토적축향순배가사재압축시험,연구료순배가사재하,혼응토재불동응변속솔화측압하적동태역학특성변화규률。결과표명:수착측압적증가,혼응토항압강도적솔민감성강저;혼응토적봉치응변수응변속솔적증대총체정현감소적추세,차수착측압적증대,봉치응변축점증대。수착응변속솔적증가,혼응토순배가사재응력–응변전곡선소경력적순배차수축점감소,차전곡선외포락선상승단형상유래유“두”。당응변속솔일정시,수착측응력적증대,봉치응력이전순배차수불단증다,즉측응력연완료손실,추지료파배。
The axial compression test under cyclic loading and unloading with side pressure of the concrete is conducted in this paper. The law of dynamic change of mechanical property of the concrete is studied under cyclic loading and unloading with different side pressures and strain rates. The results show that with the increase of confining pressure, the compressive strength of concrete rate sensitivity decreased; the concrete peak strain with strain rate increasing showing an overall decreasing trend and with the increase of confining pressure, peak strain increases gradually. With the increase of strain rate, the cyclic number of cyclic loading and unloading stress-strain curves of concrete decreases gradually, and the curve of the whole curve is getting more and more steep. When the strain rate is constant, with the increase of the lateral stress, the peak stress of the cyclic number is increasing, that is, the side stress has delayed the loss, and has delayed the damage.