Despite its critical location, right on top of the Main Himalayan Thrust, the building stock of Nepal is mainly constituted by highly vulnerable non-engineered unreinforced masonry (URM) buildings. Most of them were realized with traditional construction techniques and locally available materials like field stones and mud mortar. The empirical evidence from historical earthquakes has shown that these buildings have very limited seismic capacity. On the contrary, if adequate retrofitting interventions are implemented, their seismic performance can improve substantially. Unfortunately, the upfront investment required by retrofitting remains an issue since it is considered too high and not associated with an immediate and tangible benefit. This prevents building owners and investors from retrofitting properties as preparedness measure. Starting from these considerations, this work presents an incremental approach for the implementation of retrofitting so that the total investment is spread over time in a gradual and cost-effective way. In details, two government-approved retrofitting approaches for Nepali stone in mud mortar masonry (SMM) buildings are broken down into phases and analysed from an engineering and financial perspective. A probabilistic cost-benefit analysis of each phase is carried out to quantify the return on investment and the payback time of seismic enhancement. Results indicate that retrofitting is a financially advantageous investment since the reduction in future earthquake-induced loss exceeds the upfront cost of the intervention. Additionally, the incremental approach allows more flexibility in implementing effective risk management actions at regional and national scale.

尽管处于关键位置，但在喜马拉雅山主推力的顶部，尼泊尔的建筑群主要由高度脆弱的非工程非钢筋砌筑（URM）建筑物组成。其中大多数是通过传统的建筑技术和当地可用的材料（例如田间石材和泥浆）实现的。历史地震的经验证据表明，这些建筑物的抗震能力非常有限。相反，如果实施适当的改造措施，其抗震性能将大大提高。不幸的是，由于被认为太高并且与直接的和有形的利益无关，因此翻新所需的前期投资仍然是一个问题。这样可以防止建筑物的所有者和投资者将房屋作为防备措施进行改造。从这些考虑出发，这项工作提出了一种用于实施改造的渐进方法，从而使总投资随着时间的流逝以一种渐进的，具有成本效益的方式进行分配。详细而言，将两种政府批准的尼泊尔砂浆砌筑（SMM）建筑中的石材翻新方法分解为多个阶段，并从工程和财务角度进行了分析。进行了每个阶段的概率成本效益分析，以量化抗震加固的投资回报率和投资回收期。结果表明，由于未来地震造成的损失减少超过了干预的前期成本，因此改造是一项财务上有利的投资。此外，