论文标题
加热引起的在滑坡应力水平缓慢至快速剪切期间粘土的加强或削弱
Heating-induced strengthening or weakening of clays during slow to fast shearing at landslide stress levels
论文作者
论文摘要
滑坡剪切区的温度变化可以从摩擦加热中得出，但也可以与地下水流量或与大气相交换。这在季节性和长期气候强迫下的浅滑坡中尤其重要。温度如何控制这些滑坡中的剪切电阻受到限制。我们探索了在滑坡应力水平（50-150 kPa）和缓慢的剪切剪切（0.018-44.5 mm/min）下的两种纯粘土（Ca碳酸盐和高岭土）的响应。我们修改了一个环形装置以允许温度控制（20-50 C）。我们观察到在缓慢的剪切过程中，重要的加热引起的膨润土增强，但在更快的剪切过程中也会减弱并再次加强。与膨润土相比，高岭土的影响通常相反，幅度较低。尽管在天然土壤中需要进行更多的分析，并且在较低的温度范围内，我们认为，粘土的热敏感性不仅在快速和大的粘土中可能很重要，而且在粘土土壤中的缓慢而浅的滑坡中也很重要。但是，应进行逐案研究，以评估热灵敏度如何与大气 - 土壤相互作用的同时过程相结合。
Changes in temperature in landslide shear zones can derive from frictional heating but also groundwater flow or heat exchange with the atmosphere. This is especially relevant in shallow landslides under seasonal and long-term climatic forcing. How temperature controls the shear resistance in these landslides is poorly constrained. We explored the response of two pure clays (Ca-bentonite and kaolin) under landslide stress levels (50-150 kPa) and slow-to-rapid shearing (0.018-44.5 mm/min). We modified a ring-shear device to permit temperature control (20-50 C). We observed important heating-induced strengthening in bentonite during slow shearing, but also weakening and again strengthening during faster shearing. Effects in kaolin were generally of opposite sign and lower magnitude compared to those in bentonite. Although more analyses are warranted in natural soils and in a lower temperature range, we argue that the thermal sensitivity of clays may matter not only in fast and large, but also in slow and shallow landslides in clay soils. However, case-by-case investigations should be performed to evaluate how thermal sensitivity combines with concurrent processes of atmosphere-soil interaction.
