Effects of Tar on CPT and Shear Wave Velocity Correlations for the LA Metro Purple Line (D-Line)
Effects of Tar on CPT and Shear Wave Velocity Correlations for the LA Metro Purple Line (D-Line)
复制标题
焦油对洛杉矶地铁紫线（D 线）CPT 和剪切波速度相关性的影响
DOI：
10.1061/9780784484708.019
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
O’Rourke, Thomas D.
中科院分区：
文献类型：
--
作者：
Chrysovergis, Taki;Lemnitzer, Anne;Star, Lisa M.;Rodriguez, Joseph;Hashash, Youssef;Sathialingam, Namasivayam;Cording, Edward;O’Rourke, Thomas D.
洛杉矶（LA）地铁紫线（D线）延伸项目需要设计和施工深车站开挖和隧道，用于从市中心到洛杉矶西部的轨道交通。西区紫线延伸1施工的2号河段的隧道定线横切天然存在的焦油灌注土壤，已知这会在加州南部以及世界各地的许多其他地方造成具有挑战性的施工条件。比较了两个地质相似但位于焦油土壤内外的监测站。隧道和车站开挖的土壤调查包括地下勘探，包括深层土壤钻孔、圆锥贯入测试（CPT）、地震速度测量、压力计测试和气体测量等。CPT和剪切波速度测试的结果提供了广泛的数据，在焦油土壤独特的南加州和一个机会，以增加我们的理解四相土壤材料和焦油对土壤行为的解释和工程性质的影响。CPT相关性常规（非焦油注入）土壤被认为是不够的焦油土壤在洛杉矶盆地。在焦油土壤中测定的CPT土壤行为类型指数（SBTn）表明存在比实验室测试和现场观察确定的更细粒度的材料。此外，焦油土壤的存在放大了剪切波速度（Vs）和直接Vs地震CPT测量的CPT相关性之间的差异。
The Los Angeles (LA) Metro Purple Line (D-Line) Extension project requires the design and construction of deep station excavations and tunnels for rail transit from downtown to west LA. The tunnel alignment for Reach 2 of the Westside Purple Line Extension 1 construction transects naturally-occurring tar-infused soils, which have been known to cause challenging construction conditions in southern California, as well as many other locations around the world. Two stations in similar geology but located within and outside tar soils were compared. The soil investigations of the tunnels and station excavations consisted of subsurface exploration including deep soil borings, Cone Penetration Testing (CPT), seismic velocity measurements, pressuremeter testing, and gas measurements, among others. The results of CPT and shear-wave velocity testing provide extensive data in tar soils unique to Southern California and an opportunity to increase our understanding of four-phase soil materials and the effects of tar on soil behavior interpretation and engineering properties. CPT correlations for conventional (non-tar-infused) soils were found to be inadequate for tar soils in the Los Angeles basin. The CPT based Soil Behavior Type Index (SBTn) determined in tar soils suggested the presence of much finer-grained material than determined from laboratory testing and field observations. Additionally, the presence of tar soils amplified the difference between CPT correlations for shear wave velocity (Vs) and direct Vsseismic CPT measurements.