With the thermal disturbance caused by engineering construction and global warming, thaw consolidation has become a primary source of subgrade deformation in permafrost regions. Based on the large-strain consolidation theory described by the updated Lagrangian, we study the thermal stability and the thaw consolidation in an ordinary subgrade at the warm and ice-rich permafrost (WIRP) site of the Beiluhe Qinghai-Tibet Railway (QTR) by establishing a thermo-mechanical coupled model. The research results are as follows: The initial mean annual ground temperature (MAGT) of the site influences the permafrost degradation on the Qinghai-Tibet Plateau due to construction and climate warming, exacerbating the thaw consolidation and creep of the ice-rich permafrost. The settlement rate and subgrade settlement increase with increasing embankment height, ice-rich permafrost layer thickness, and initial MAGT. Railway maintenance methods, such as ballast filling and track lifting, increase the subgrade weight, thus increasing the WIRP subgrade settlement. Furthermore, we predict the thaw consolidation of the DK1136 section of the QTR for the next 50 years. The prediction formulas of the cumulative settlements of the subgrade top and permafrost are established, and various suggestions for maintaining the railway subgrade of the WIRP site are proposed.

由于工程建设和全球变暖引起的热干扰，融化固结已成为多年冻土地区路基变形的主要来源。基于更新的拉格朗日方程描述的大应变固结理论，我们通过以下方法研究了北陆河青藏铁路（QTR）温暖且富含冰的多年冻土（WIRP）站点的普通路基的热稳定性和解冻固结：建立热力耦合模型。研究结果如下：该地点的初始年平均地面温度（MAGT）由于施工和气候变暖影响青藏高原的多年冻土退化，加剧了富冰多年冻土的融化固结和蠕变。随着路堤高度的增加，沉降率和路基沉降量增加，富含冰的多年冻土层厚度和初始MAGT。铁路维护方法（例如压载物填充和轨道提升）增加了路基的重量，从而增加了WIRP路基沉降。此外，我们预计未来50年QTR DK1136部分的融化合并。建立了路基顶部和多年冻土累积沉降的预测公式，并提出了各种维护WIRP工地铁路路基的建议。