岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2013年
7期
1881-1886
,共6页
姜德义%范金洋%陈结%任松%王震%白月明
薑德義%範金洋%陳結%任鬆%王震%白月明
강덕의%범금양%진결%임송%왕진%백월명
盐岩%围压卸荷%扩容损伤%温度效应
鹽巖%圍壓卸荷%擴容損傷%溫度效應
염암%위압사하%확용손상%온도효응
salt rock%unloading confining pressure%dilatancy damage%temperature effect
通过试验模拟盐岩储气库建腔期腔体围岩围压动态降低过程,开展单轴压缩和三轴卸荷扩容试验,并分析温度对盐岩试件卸荷扩容特征的影响。试验结果表明:由于都是应力增加的过程,卸荷试验的扩容特征与常规单轴试验相比,在扩容阶段划分上具有一些共同点,都存在体积压缩段、稳定扩容段和加速扩容段。卸荷试验和单轴试验的压缩极限基本相同。但由于加载方式不同,卸荷试验的稳定扩容段在整体扩容中所占比例更小,扩容速率和扩容幅度也较单轴试验小。在相同的偏应力作用下,卸荷试验产生更大的扩容。温度升高能够促进盐岩的扩容,表现为加速扩容点前移、初始稳定扩容段缩短、加速扩容段变长、扩容速度加快、扩容幅度增大等。
通過試驗模擬鹽巖儲氣庫建腔期腔體圍巖圍壓動態降低過程,開展單軸壓縮和三軸卸荷擴容試驗,併分析溫度對鹽巖試件卸荷擴容特徵的影響。試驗結果錶明:由于都是應力增加的過程,卸荷試驗的擴容特徵與常規單軸試驗相比,在擴容階段劃分上具有一些共同點,都存在體積壓縮段、穩定擴容段和加速擴容段。卸荷試驗和單軸試驗的壓縮極限基本相同。但由于加載方式不同,卸荷試驗的穩定擴容段在整體擴容中所佔比例更小,擴容速率和擴容幅度也較單軸試驗小。在相同的偏應力作用下,卸荷試驗產生更大的擴容。溫度升高能夠促進鹽巖的擴容,錶現為加速擴容點前移、初始穩定擴容段縮短、加速擴容段變長、擴容速度加快、擴容幅度增大等。
통과시험모의염암저기고건강기강체위암위압동태강저과정,개전단축압축화삼축사하확용시험,병분석온도대염암시건사하확용특정적영향。시험결과표명:유우도시응력증가적과정,사하시험적확용특정여상규단축시험상비,재확용계단화분상구유일사공동점,도존재체적압축단、은정확용단화가속확용단。사하시험화단축시험적압축겁한기본상동。단유우가재방식불동,사하시험적은정확용단재정체확용중소점비례경소,확용속솔화확용폭도야교단축시험소。재상동적편응력작용하,사하시험산생경대적확용。온도승고능구촉진염암적확용,표현위가속확용점전이、초시은정확용단축단、가속확용단변장、확용속도가쾌、확용폭도증대등。
The dynamic reduction of confining pressure of salt rock gas storage surrounding rock during construction period is simulated by uniaxial compression tests and triaxial unloading confining pressure tests. The effect of temperature on dilatancy characteristics of salt rock are analyzed by the unloading tests. The results show that all the tests are the process of stress increasing. Furthermore, both unloading confining pressure tests and uniaxial compression tests have similar deformation stages of dilatancy curves. The similar deformation stage includes the volume compressed segment, the stable dilatancy segment and the accelerating dilatancy segment. Those two types of tests also have the similar compressed limit. However, due to the different loading modes, the ratio of stable dilatancy in uniaxial tests is larger than that in unloading confining pressure experiments. The dilatancy rate and the value of dilatancy are smaller in unloading confining pressure tests. The unloading confining pressure tests have greater dilatancy under the same deviatoric stress. Higher temperature can promote the dilatancy of salt rock. That means the increasing of temperature can make the accelerating dilatancy point appear forward, the initial stable dilatancy segment shorter, the accelerating dilatancy segment longer, the dilatancy rate and the value of dilatancy higher.