In order to predict the bearing capacity of steel plate-concrete reinforced composite (SPRC) coupling beams more conveniently. In this paper, it is of great significance to study the bearing capacity prediction model of SPRC coupling beams by machine learning (ML) method. Firstly, the SPRC coupling beam database is established by collecting the existing experimental data. On this basis, six ML algorithms, including extreme learning machine (ELM) algorithm, back propagation neural network (BPNN) algorithm, support vector machine (SVM) algorithm, K-nearest neighbor (KNN) algorithm, random forest (RF) algorithm and extreme gradient boosting (XGBoost) algorithm were used for data regression training. Through the comparative analysis of model performance indicators, it is found that the prediction model based on XGBoost algorithm has the best robustness and generalization ability. Compared with the softened strut-and-tie model (SSTM), it has higher calculation accuracy and stability. A high-precision SPRC coupling beam bearing capacity prediction model based on ML method is proposed. In addition, the sensitivity analysis of the parameters affecting the bearing capacity of SPRC coupling beams is also carried out. The results show that the influence degree of each characteristic parameter on the bearing capacity of SPRC coupling beams is in descending order as follows: steel plate ratio (ρp), coupling beam section height (h), coupling beam section width (b), span-depth ratio (ln/h), stirrup yield strength (fvy), longitudinal reinforcement ratio (ρs), longitudinal reinforcement yield strength (fsy), stirrup ratio (ρt), steel plate yield strength (fpy), concrete compressive strength (fcu).
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |