Simulation of rock moisture and weathering conditions in Gesäuse National Park

The surveys carried out in this thesis aimed to introduce the simulation of rock moisture and weathering conditions on rock walls to the prevailing natural conditions. For this purpose, the influence of the area-specific rain and snow precipitation on the hygrothermal rock conditions in the Gesäuse National Park was investigated. By means of impact rain-specific climatic surveys in the Gsenggraben and with snow modelling carried out in the ESCIMO.spread program, the prevailing natural conditions in the investigation area could be integrated into the WUFI simulation program. WUFI, originally developed for buildings, offers a wealth of operational possibilities that make targeted simulations feasible. The adjustments made primarily led to an increased moisture input into the simulated system, which results in about 70 % of the consideration of the snow influence on the conditions prevailing in the rock. This ratio is also reflected in the simulations carried out in order to detect exposure- and off-road inclination-specific influences in which four orientations north, east, south and west were made at a slope of 70 and 90. Throughout, a recognizable influence of the increasingly occurring impact on pore saturation and the weathering-relevant parameters can be determined. This is consistently surpassed by the snowfall flowing into the simulation. Due to the approximation to the natural conditions in the rock, a higher pore saturation level as well as an increased weathering potential can be detected. For the weathering itself, the ice lens theory could be established as a decisive process, which comes closer to the real processes in the rock than the classic frost change theory.本论文开展的调研工作，旨在将岩壁水分与风化条件的模拟适配于研究区域的实际自然环境。为此，本研究针对格塞国家公园（Gesäuse National Park）区域专属的雨雪降水对岩体湿热环境的影响展开了系统调研。 通过在格斯恩格拉本（Gsenggraben）开展的针对性降雨气候观测，以及借助ESCIMO.spread程序完成的积雪模拟，本研究可将调查区域的实际自然环境参数导入WUFI模拟程序中。WUFI最初为建筑领域研发，具备丰富的运行配置选项，可实现精准的模拟计算。 本次所作的参数调整主要提升了模拟系统中的水分输入量，使积雪对岩体实际环境的影响占比约为70%。该比例同样体现在本次模拟实验中：为探究坡面朝向与倾角的专属影响，研究设置了北、东、南、西四个坡面朝向，分别采用70°与90°的坡面坡度。 全程实验均可观测到，降雨冲击对岩体孔隙饱和度及风化相关参数的影响愈发显著。而模拟中引入的降雪影响，其作用强度始终超过上述降雨冲击的影响。由于本次模拟尽可能贴合岩体的实际自然环境，实验中可观测到更高的孔隙饱和度水平，以及更强的风化潜能。 针对岩体风化过程本身，冰透镜体理论可被认定为关键作用机制，相较于经典冻融变化理论，该理论更贴合岩体内部的真实风化过程。