## 1 Introduction  
Rockfall refers to the collapse of rocks on steep cliffs and slopes due to gravity [1, 2, 3]. Human activities have expanded, leading to increased environmental damage and extreme weather events like heavy rainfall. This has caused a rise in the occurrence of natural disasters such as rockfalls [4, 5, 6, 7]. Rockfalls, the most common type of disaster affected by climate, will have a great impact on roads and other infrastructure and result in significant human and economic losses annually [8, 9]. In 2015, a passenger train derailed in Northfield, Vermont, after colliding with rockfall debris, resulting in extensive injuries to passengers [10]. On 5 April 2021, a Hongya rockfall avalanche resulted in the deaths of three individuals [11]. The formation of rockfalls is influenced by regional topography, geomorphology, lithology, vegetation, and geological and meteorological conditions [12; 13; 14]. Predicting and mitigating rockfall risks and conducting risk assessments have become key research areas as rockfall incidents increase [15; 16]. Guizhou Province, located in the mountainous region of southwestern China, is characterized by a delicate geological environment that renders it particularly vulnerable to rockfall disasters [17]. As of the end of 2022, the province is projected to encompass approximately 8472 km of highways, positioning it fourth nationally in terms of highway infrastructure. The occurrence of rockfall events on these vital transportation routes can lead to severe traffic congestion, compromise the structural integrity of roadways, and pose significant threats to public safety and property. In light of the escalating frequency of rockfall incidents and their potentially catastrophic consequences, it is imperative to undertake an urgent and comprehensive assessment of rockfall risks along Guizhou's highways. Immediate action is warranted to devise and implement robust risk mitigation and management strategies, thereby ensuring the safety of travelers and the sustained integrity of the transportation infrastructure. This proactive approach is essential to avert future disasters and safeguard both human lives and economic assets. Rockfall risk assessment can be categorized into two types: regional-scale assessment through rockfall risk maps and small-scale assessment through rockfall disaster simulations to analyze rockfall movement characteristics and assess risks. Both methods utilize modern computer technology and Geographic Information System (GIS) technology [10; 18]. Highway rockfall risk assessment in Guizhou Province is primarily conducted on a large regional scale using a risk mapping approach. The risk mapping methodology includes qualitative and quantitative assessments, with quantitative methods gradually becoming more prevalent as research and technology advance [19; 20]. The most common quantitative methods include the analytic hierarchy process (AHP) assessment system [21], expert experience scoring [22], the comprehensive fuzzy evaluation model [23], the information content method [24], logistic regression [25], the frequency ratio method [26], and machine learning models [27; 28; 29; 30; 31]. The AHP assessment system, expert experience scoring, and comprehensive fuzzy evaluation model are known for their simplicity and ease of implementation. However, the risk evaluation model constructed using these methods may be heavily influenced by human subjectivity [32]. Machine learning models offer high prediction accuracy but require a large amount of data for learning and training, making the modeling process complex and difficult to understand [33] The information content method involves analyzing the interval area of each rockfall hazard impact indicator and the number of rockfall hazards to determine the probability of a rockfall accident occurrence due to each impact indicator [34].