Biochar is an eco-friendly material that is potentially used in earthworks to prevent stability and serviceability problems under extreme scenarios. This study aims to examine the effects of biochar amended on water infiltration and evaporation under extreme climate. A series of numerical analyzes were conducted to observe the response of pore water pressure (PWP) to extreme climate variation with an application of biochar composition. Moreover, an analysis of variance (ANOVA) has been performed to investigate the effect of biochar on soil water holding capacity at a low suction range. According to the result, biochar amended can maintain the fluctuation of PWP due to wetting and drying processes under extreme climate scenarios. This is due to the fact that the finer particles of biochar may clog large soil pores, reducing the water infiltration rate. Moreover, the addition of biochar can increase water retention capacity at low matric suction ranges, which can prevent flooding during extreme wet conditions. Further to this, the addition of biochar to the soil can maintain PWP fluctuation at the near surface area under extreme climate, preventing soil desiccation cracks.

生物炭是一种环保材料，可用于土方工程，以防止极端情况下的稳定性和适用性问题。本研究旨在研究极端气候下修改后的生物炭对水渗透和蒸发的影响。通过应用生物炭组合物进行了一系列数值分析，以观察孔隙水压力（PWP）对极端气候变化的响应。此外，还进行了方差分析（ANOVA）来研究生物炭在低吸力范围内对土壤持水能力的影响。结果表明，修正后的生物炭可以在极端气候条件下维持干湿过程引起的PWP波动。这是因为生物炭的细颗粒可能会堵塞大的土壤孔隙，降低水的渗透率。此外，生物炭的添加可以提高低基质吸力范围内的保水能力，从而可以防止极端潮湿条件下的洪水。此外，在土壤中添加生物炭可以在极端气候下维持近地表区域的 PWP 波动，防止土壤干裂。