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Bridges are critical links in a transportation network that are susceptible to seismic actions, their vulnerability assessment is essential for seismic risk assessment and mitigation. In order to explore the damage probability of long span prestressed concrete continuous rigid frame bridge in the event of earthquake, this study took the Longxi Jialing River Bridge as an example and presents seismic vulnerability assessment based on the incremental dynamic analysis method. Taking the curvature of the pier's most unfavorable section as the damage index, the seismic vulnerability curve of the pier was established with peak acceleration(PGA) as the independent variable and the probability of the structure exceeding a specific damage state as the dependent variable. Results demonstrate that under the action of a near-field earthquake, when PGA =0.5 g, the failure probabilities of slight damage is 0.02926, the failure probabilities of moderate damage is 0.01823, and the failure probabilities of severe damage is 0.00075. When PGA = 1.0 g, the failure probabilities of slight damage is 0.672 and 0.597 for moderate damage, 0.20109 for severe damage, and 0.00484 for complete damage. Under the action of a far-field earthquake, when PGA = 0.5 g, the failure probability of slight damage is 0.00194, and the failure probability of moderate damage is 0.00101 along the span direction. When PGA = 1.0 g, the failure probability of slight damage is 0.04358, 0.02802 for moderate damage, and 0.00138 for serious damage along the span direction. The complete damage of the bridge hardly occurs. With the increase of intensity of an earthquake, the failure probability of the pier gradually increases. After entering the moderate damage stage, the pier has relatively good ductility. This study provides a good reference for the seismic design of similar bridges. [ABSTRACT FROM AUTHOR]

Simple Summary: Adaptations to environments are crucial for wild animals to survive changing habitats. We study the feeding postures and forest strata use of François' langurs to explore how these langurs behaviorally adapt to limestone forests. We found that these langurs used sitting as the most frequent feeding posture and tended to use the lower and middle forest during feeding, which is likely linked to food resource availability. Our result demonstrates that the spatial distribution of foods in the limestone forest has an important effect on the feeding posture of the François' langurs and their forest layer utilization, highlighting the importance of understanding the effect of ecological factors on the adaptation of the langurs to the unique limestone habitat. The feeding posture of a group of François' langurs in Fusui County, Guangxi, was studied using instantaneous scan sampling from January to December 2016 to explore how the species adapts to karst limestone forests by collecting data on feeding posture, forest strata height, and substrate use. The results showed that leaves were the main food type of the François' langurs, with young leaves accounting for 64.97% ± 19.08% of the food composition, mature leaves accounting for 11.88% ± 12.09%, fruits accounting for 12.96% ± 12.89%, flowers accounting for 4.16% ± 4.06%, and other food types, including stems, petioles, and other unknown parts of the tree, accounting for a total of 6.03% ± 9.09%. The François' langurs had four main postures during feeding, of which sitting and bipedal standing feeding accounted for the largest proportions, at 85.99% ± 5.97% and 12.33% ± 6.08% of the total records, respectively. Quadrupedal standing and suspending were rarely observed and only appeared occasionally during feeding activities at the peak resting period, the two postures together accounting for 1.39% ± 1.59% of the total records. The feeding postures of the langurs had marked seasonal variation, as evidenced by the fact that seated feeding accounted for a significantly higher proportion of the total behavioral records in the rainy season than in the dry season, whereas feeding while standing bipedally was significantly more frequent during the dry season. Correlation analyses showed that feeding posture was correlated with food composition, showing a positive correlation between the proportion of bipedal standing feeding and mature leaf consumption. François' langurs preferred to forage in the lower and middle forest layers, with the lower forest layer accounting for 55.93% ± 16.50% of the total number of recordings and the middle forest layer accounting for 33.63% ± 18.33%. Langurs were less likely to forage on the ground (rocks), accounting for only 6.79% ± 4.78% of the records. The frequency of langurs feeding in the upper part of the forest layer was the lowest at 3.65% ± 2.73%. Additionally, in the dry season, langurs utilized the lower forest layer more but used the middle forest layer less than in the rainy season. This study demonstrates that the spatial distribution of foods in the limestone forest has an important effect on the feeding posture of François' langurs and their forest layer utilization. [ABSTRACT FROM AUTHOR]