引黄济宁工程拉脊山越岭隧洞超深钻孔地应力梯段测试
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摘要
引黄济宁拉脊山越岭隧洞长33 km,最大埋深约1 650 m。洞穿青藏高原高大雄峻的拉脊山山脉。为了掌握越岭隧道的不同埋深段地应力量值和方向,在867 m的超深钻孔内采用水压致裂法自250 m以下每50～60 m分不同深度进行了16段地应力测试。结果表明:在测试深度范围内,最大水平主应力值为24. 37 MPa,最大水平主应力的优势方向为NE23°左右,与现代区域构造应力场特征、水平地应力的回归对比分析和数值模拟分析等结果一致,说明测试成果合理可靠。
The length of the Laji Mountain summit tunnel of the Yellow River to Xining Water Diversion Project is 33 km and the maximum depth is about 1 650 m. The tunnel runs through the Laji Mountains of the Qinghai-Tibet Plateau. In order to understand the magnitude and direction of the in-situ stress at different depths of the tunnel,the 16-segment in-situ stress test was carried out in the 867 m ultra-deep borehole by hydraulic fracturing method starting from 250 m for every 50 ～ 60 m at different depths. The results show that the maximum horizontal principal stress is 24. 37 MPa and the dominant direction of the maximum horizontal principal stress is about NE23°within the test depth range. It is consistent with the characteristics of the recent regional tectonic stress field,the regression analysis and numerical simulation analysis of horizontal ground stress,indicating that the test results are reasonable and reliable.
The length of the Laji Mountain summit tunnel of the Yellow River to Xining Water Diversion Project is 33 km and the maximum depth is about 1 650 m. The tunnel runs through the Laji Mountains of the Qinghai-Tibet Plateau. In order to understand the magnitude and direction of the in-situ stress at different depths of the tunnel,the 16-segment in-situ stress test was carried out in the 867 m ultra-deep borehole by hydraulic fracturing method starting from 250 m for every 50 ～ 60 m at different depths. The results show that the maximum horizontal principal stress is 24. 37 MPa and the dominant direction of the maximum horizontal principal stress is about NE23°within the test depth range. It is consistent with the characteristics of the recent regional tectonic stress field,the regression analysis and numerical simulation analysis of horizontal ground stress,indicating that the test results are reasonable and reliable.
引文
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[3]袁风波,刘建,李蒲健,等.拉西瓦工程河谷区高地应力场反演与形成机理[J].岩土力学,2007,28(04):836-842.
[2]傅金筑.对李家峡水电站地下洞室围岩稳定问题的讨论[J].西北水电,1992(02):36-42.
[3]袁风波,刘建,李蒲健,等.拉西瓦工程河谷区高地应力场反演与形成机理[J].岩土力学,2007,28(04):836-842.