水利水电科技进展
水利水電科技進展
수이수전과기진전
ADVANCES IN SCIENCE AND TECHNOLOGY OF WATER RESOURCES
2014年
6期
36-39,44
,共5页
自密实轻骨料混凝土%三点弯曲梁%断裂过程区%裂缝扩展阻力曲线
自密實輕骨料混凝土%三點彎麯樑%斷裂過程區%裂縫擴展阻力麯線
자밀실경골료혼응토%삼점만곡량%단렬과정구%렬봉확전조력곡선
self-compacting lightweight concrete%three-point bending beam%fracture process zone%KR-curves
为研究自密实轻骨料混凝土的断裂特性,引入以起裂断裂韧度为参数的裂缝扩展准则,采用数值方法分析了自密实轻骨料混凝土三点弯曲梁裂缝扩展的全过程,得到了不同缝高比的自密实轻骨料混凝土梁在三点荷载下的荷载裂缝口张开位移曲线,并根据裂缝扩展准则,计算了自密实轻骨料混凝土的断裂过程区长度和裂缝扩展阻力曲线。结果表明:试验和计算的荷载裂缝口张开位移曲线吻合良好,验证了裂缝扩展准则的正确性;试验断裂过程区长度随着裂缝增长先增大,达到完整断裂过程区长度后减小;自密实轻骨料混凝土的裂缝阻力随着裂缝长度增加而不断增大,初始缝高比对裂缝扩展阻力曲线数值和形状的影响并不明显。
為研究自密實輕骨料混凝土的斷裂特性,引入以起裂斷裂韌度為參數的裂縫擴展準則,採用數值方法分析瞭自密實輕骨料混凝土三點彎麯樑裂縫擴展的全過程,得到瞭不同縫高比的自密實輕骨料混凝土樑在三點荷載下的荷載裂縫口張開位移麯線,併根據裂縫擴展準則,計算瞭自密實輕骨料混凝土的斷裂過程區長度和裂縫擴展阻力麯線。結果錶明:試驗和計算的荷載裂縫口張開位移麯線吻閤良好,驗證瞭裂縫擴展準則的正確性;試驗斷裂過程區長度隨著裂縫增長先增大,達到完整斷裂過程區長度後減小;自密實輕骨料混凝土的裂縫阻力隨著裂縫長度增加而不斷增大,初始縫高比對裂縫擴展阻力麯線數值和形狀的影響併不明顯。
위연구자밀실경골료혼응토적단렬특성,인입이기렬단렬인도위삼수적렬봉확전준칙,채용수치방법분석료자밀실경골료혼응토삼점만곡량렬봉확전적전과정,득도료불동봉고비적자밀실경골료혼응토량재삼점하재하적하재렬봉구장개위이곡선,병근거렬봉확전준칙,계산료자밀실경골료혼응토적단렬과정구장도화렬봉확전조력곡선。결과표명:시험화계산적하재렬봉구장개위이곡선문합량호,험증료렬봉확전준칙적정학성;시험단렬과정구장도수착렬봉증장선증대,체도완정단렬과정구장도후감소;자밀실경골료혼응토적렬봉조력수착렬봉장도증가이불단증대,초시봉고비대렬봉확전조력곡선수치화형상적영향병불명현。
In order to study the fracture characteristics of self-compacting lightweight concrete ( SCLC ) , the crack propagation criterion, which uses initial cracking toughness as the main parameter is used to numerically analyze the complete process of crack propagation in SCLC three-point bending beam. The criterion was verified by the reasonable agreement between calculated and experimental load-crack mouth opening displacement. According to the criterion, the length of fracture process zone ( FPZ) and KR-curves of SCLC can be obtained. The results show that FPZ length increases with the crack extension and decreases after the full FPZ length. KR of SCLC specimens increases as the crack length increases and KR-curves of SCLC specimens, with different initial crack length ratio, shows insignificant differences in terms of shape and value.