软土地区的城市交通枢纽、地下铁道、超高层建筑、高速公路与铁路等的建设涉及到大量深基坑、地下隧道、软土路基处理等。这些工程的建设不同程度地改变了工程周边环境场地中土体应力场和渗流场，当应力场、渗流场异常或甚至出现水土流失时可造成土体、土中结构物的局部破坏，并由局部破坏甚至引发大范围连续破坏，有些连续破坏的损失、环境与社会影响甚至可比建筑物、桥梁等的连续破坏更严重，由软弱土体-地下水-土中结构物组成的岩土与地下工程的共同作用及破坏机理有时可能更为复杂。提出了岩土与地下工程的连续破坏问题，拟针以软土富水地层中的大型复杂深基坑工程、地下隧道和软土中复合地基支承路堤为代表的软土工程，开展局部破坏发生、发展及最终发展为连续破坏的全过程中土体-地下水-结构体的复杂相互作用和连续破坏机理研究，提出软土工程的连续破坏性能评价指标体系和评价方法，系统建立重要软土工程的防连续破坏理论和基于防连续破坏的设计方法。

There are more and more deep excavation，underground tunnel, and soft ground improvement projects in or on soft ground to be constructed with the development of metro, high-rise building and skyscraper, highway and railway, underground transportation hub in soft ground area. The construction of these projects inevitably changes the stress field and seepage field of soil and unground water in the surroundings. When the change of stress field and stress field are beyond certain extent, or even accompanied with soil erosion, water and soil loss due to leakage in underground engineering and deep excavation, local failure of underground structure or soil can happen and may finally lead to progressive failure. The progressive failure of deep excavation，underground tunnel, and soft ground improvement projects can caused more severe loss and produce more significant impact on surrounding environment and more extensive social impact than that of a building or a bridge. Since deep excavation，underground tunnel, and embankment supported soft ground improved with piles are composed of soil, underground water and structure, this makes the interaction and failure mechanism of soil-underground water-structures more complicated. Therefore, the progressive failure problem of soft soil engineering of geotechnical engineering and underground engineering is raised. The interaction of soil-water-structure and the progressive mechanism of soft ground engineering such as deep excavation，underground tunnel, and soft ground improvement projects during the whole failure evolution process starting with local failure, then the evolution and propagation of failure, until the end of progressive failure. The quantitative indexes and method to evaluate the possibility of a soft soil engineering being subjected to progressive failure are to be proposed. Finally, the anti-progressive failure theory and corresponding design method of important engineering projects in or on soft soil are to be suggested.