Structural Size Influencing Factors and Predictive Model of Cable Smoke Density Based on Multiple Regression Analysis

To quantitatively analyze influence mechanisms of cable structural dimensions on smoke density and establish predictive models, multiple regression analysis was employed. Coupling effects of conductor weight, silicone rubber weight and outer diameter were investigated by stratifying datasets based on a critical diameter threshold of 20 mm. Regression equations were constructed based on historical experimental data, with key variables screening through F-tests (p<0.05) and variance inflation factors (VIF<5). Results indicated that for cables with an outer diameter ≥20 mm, smoke density exhibited a positive correlation with conductor weight (β=0.011) and a negative correlation with silicone rubber weight (β=−0.045). For cables with an outer diameter <20 mm, the interaction between outer diameter and silicone rubber weight was significant (β=−0.37), while for every 1 mm increase in outer diameter, a 5% reduction in silicone rubber content was required to suppress the surge in smoke density. Model validation demonstrated that prediction errors within ±2% (R²>0.97) could provide enterprises with a quantitative design tool for material selection and structural optimization. The study transcends the limitations of traditional qualitative analysis and lays the foundation for intelligent algorithm-driven precision design of cable fire safety performance.