岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2013年
8期
2255-2263
,共9页
张淼%邹金锋%陈嘉祺%李亮%李振存
張淼%鄒金鋒%陳嘉祺%李亮%李振存
장묘%추금봉%진가기%리량%리진존
浆泡扩张%劈裂注浆%非对称荷载%注浆压力%塑性区半径
漿泡擴張%劈裂註漿%非對稱荷載%註漿壓力%塑性區半徑
장포확장%벽렬주장%비대칭하재%주장압력%소성구반경
slurry bubble expansion%fracturing grouting%asymmetric load%grouting pressure%radius of plastic region
为研究在非对称荷载作用下土体劈裂注浆压力,基于扩孔理论和统一强度准则并考虑非对称荷载的作用,建立基于扩孔理论的劈裂注浆启劈压力分析模型,推导出浆泡周围塑性区土体的应力场、位移场、塑性区半径以及启劈注浆压力的理论解答,并以工程算例进行论证。结果表明,考虑对称荷载作用下的启劈注浆启劈压力较考虑非对称荷载作用下的值要大,对称荷载作用下的分析方法低估了塑性区半径;无论是柱形劈裂还是球形劈裂,当0K ?1时,启劈压力会随着0K 的增大而增大,塑性半径会随着0K 的增大而明显减小;当0K ?1时,启劈压力会随着0K 的增大而减小,而塑性半径的变化是有限的。预先了解土体的初始应力条件对正确的确定劈裂注浆启劈压力至关重要,可为劈裂注浆的设计和施工会提供更加完善的理论依据。
為研究在非對稱荷載作用下土體劈裂註漿壓力,基于擴孔理論和統一彊度準則併攷慮非對稱荷載的作用,建立基于擴孔理論的劈裂註漿啟劈壓力分析模型,推導齣漿泡週圍塑性區土體的應力場、位移場、塑性區半徑以及啟劈註漿壓力的理論解答,併以工程算例進行論證。結果錶明,攷慮對稱荷載作用下的啟劈註漿啟劈壓力較攷慮非對稱荷載作用下的值要大,對稱荷載作用下的分析方法低估瞭塑性區半徑;無論是柱形劈裂還是毬形劈裂,噹0K ?1時,啟劈壓力會隨著0K 的增大而增大,塑性半徑會隨著0K 的增大而明顯減小;噹0K ?1時,啟劈壓力會隨著0K 的增大而減小,而塑性半徑的變化是有限的。預先瞭解土體的初始應力條件對正確的確定劈裂註漿啟劈壓力至關重要,可為劈裂註漿的設計和施工會提供更加完善的理論依據。
위연구재비대칭하재작용하토체벽렬주장압력,기우확공이론화통일강도준칙병고필비대칭하재적작용,건립기우확공이론적벽렬주장계벽압력분석모형,추도출장포주위소성구토체적응력장、위이장、소성구반경이급계벽주장압력적이론해답,병이공정산례진행론증。결과표명,고필대칭하재작용하적계벽주장계벽압력교고필비대칭하재작용하적치요대,대칭하재작용하적분석방법저고료소성구반경;무론시주형벽렬환시구형벽렬,당0K ?1시,계벽압력회수착0K 적증대이증대,소성반경회수착0K 적증대이명현감소;당0K ?1시,계벽압력회수착0K 적증대이감소,이소성반경적변화시유한적。예선료해토체적초시응력조건대정학적학정벽렬주장계벽압력지관중요,가위벽렬주장적설계화시공회제공경가완선적이론의거。
In order to study the soil fracturing grouting pressure under asymmetric loads, based on the cavity expansion theory and unified strength theory and considering the influence of the asymmetric loads, the analytical solutions of stress fields and displacement fields in the plastic regions surrounding slurry bubble, as well as the radius of plastic region and limit expansion pressure are deduced. The solutions are validated through the engineering example. The results show that grouting pressure considering the symmetrical load is larger than that considering the asymmetric loads, which indicates that the radius of plastic region are underestimated in the analysis of grouting under the symmetrical load. For the cylindrical cavity expansion and the spherical cavity expansion, where K0 is less than 1, the starting fracturing pressure increases with the increment of K0; while the radius of plastic region significantly decreases with the increment of K0. Where K0 is greater than 1, the starting fracturing pressure decreases with the increment of K0, but the change of radius of plastic region is limited. Therefore it is important to estimate the initial stress conditions of the soil previously before the critical fracturing pressure. The results will improve theoretical basis for design and construction of fracturing grouting.