Extreme rainfall causes the collapse of rammed earth city walls. Understanding the depth of rainwater infiltration and the distribution of internal moisture content is crucial for analyzing the impact of rainfall on the safety and stability of these walls. This study focuses on the rammed earth city wall at the Mall site in Zhengzhou. Based on Richards' equation, the water motion equation of rammed earth wall is deduced and established. The change of moisture content of rammed earth wall and the development of wetting front under rainfall condition are studied. The stability of the rammed earth city wall under rainfall infiltration is analyzed by finite element methods. The results show that the water motion equation can effectively describe the moisture distribution inside the rammed earth city wall during rainfall. As the rainfall continues, the wetting front deepens, and the depth of the saturated zone increases. Just below the wetting front, the moisture content decreases rapidly and eventually returns to its initial value. the water motion equation provides a theoretical basis for analyzing water-related damage in rammed earth walls. Factors such as the initial soil moisture content, rainfall duration, and rainfall intensity significantly influence the distribution of the wetting front and moisture content. The saturation of the upper soil layers reduces the shear strength of the shallow soil, leading to a decrease in the safety factor, which can result in shallow landslides and collapse of the rammed earth wall. The research results can provide theoretical support for the analysis of water infiltration law of rammed earth city walls under rainfall conditions, and provide reference for revealing the instability mechanism of rammed earth city walls induced by rainfall. (c) 2025 Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Rammed earth building has garnered attention from researchers due to its low energy consumption and excellent thermal performance. However, addressing the issue of low seismic performance in rammed earth buildings still lacks effective solutions. This study investigated the influence of embedded steel wire mesh and bamboo reinforcement mesh on the in-plane seismic performance of rammed earth walls through pseudo-static tests. Four half-scale models of rammed earth walls were constructed, each with dimensions of 1900 mm in length, 1200 mm in width, and 250 mm in height. The experimental results were compared in terms of failure mode, hysteresis response, lateral bearing capacity, displacement, ductility, stiffness degradation, damage index, and energy dissipation capability. The peak ground acceleration (PGA) for each specimen was calculated using the N2 method to assess their seismic performance. The results indicated that both steel wire mesh and bamboo reinforcement mesh can significantly enhance the seismic performance of rammed earth walls. Finally, based on the hysteresis curves of the specimens and the strain test results of the steel wire mesh or bamboo reinforcement mesh, this study proposed a hysteretic model and lateral bearing capacity calculation formula for rammed earth walls.

Building with rammed earth has become increasingly popular in recent years because it is highly sustainable and has little environmental impact. More than half of the world's population lives in earthen houses, many of which are located in earthquake-prone areas such as Croatia. However, their seismic performance still needs to be researched, especially considering local construction techniques. One of the first steps in this process is the experimental testing of such walls. Four models of rammed earth walls were constructed using traditional local building techniques and experimentally tested under in-plane cyclic loading to investigate their seismic behaviour. The model walls were built using locally available soil material. The new particle size distribution envelope for determining the suitability of soil material for rammed earth construction was proposed for the first time. The building material was chosen according to the envelope. Moreover, walls were made using two different material compositions-i.e., natural soil from eastern Croatia and man-made soil with the addition of fine gravel. The main objective, the seismic performance of the RE walls, was evaluated in terms of their bearing capacity, behaviour after yielding, failure mode, stiffness degradation, initial elastic stiffness, and energy dissipation capacity.