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Assessing post-fire recovery is essential to forecast how ecosystems will respond to future warmer conditions and higher fire severity. Such assessments must consider site conditions and the post-fire recovery of trees and shrubs. We used tree-ring data and intrinsic water-use efficiency (WUEi) to quantify the post-fire responses of a tree (Pinus pinea) and a shrub (Juniperus phoenicea) in Mediterranean coastal dunes located in the Doñana protected area, SW Spain. We compared pines and junipers growing in an inter-dune slack with those growing in a nearby dune ridge. We quantified crown damage and bark char in pines impacted by a wildfire. Pines with lower crown damage after the fire showed a higher growth rate one year later. Growth decreased afterwards in the case of fast-growing pines from the slack site, whereas slow-growing dune pines showed increasing growth rates one to three years after the fire. The fire did not change the pines' WUEi, whereas the junipers located in dunes presented the highest WUEi values. Severe crown damage (damage > 60%) impairs long-term growth recovery in P. pinea. Open and heterogeneous landscapes can reduce the wildfire risk in the study Mediterranean area, where slack vs. dune and tree vs. shrub differences should be considered in post-fire management plans. [ABSTRACT FROM AUTHOR]

This experimental investigation reveals the projected benefits of concrete-filled double-skin tubular columns. These columns are made up of an outside steel tube, an interior UPVC pipe, and a sandwich of concrete among these tubes. The effect of the dimension ratio of the outer-to-inner tube, the thickness ratio of the outer tube, and the internal tube material (steel/UPVC) on the ultimate compressive strength of double-skin tubular columns samples filled with concrete are investigated. Finally, the experimental findings were compared to previously published design approaches in AISC (2010), GB50936 (2014), and EC4 (2004). The analysis revealed that GB50936 (2014) produces the best outcomes, followed by AISC (2010) and EC4 (2004). In addition, the samples were tested in elevated temperatures to study their post-fire axial capacity. It was discovered that the type of infilled concrete and interior tube material has no major impact on the performance of samples at elevated temperatures.

Assessing post-fire recovery is essential to forecast how ecosystems will respond to future warmer conditions and higher fire severity. Such assessments must consider site conditions and the post-fire recovery of trees and shrubs. We used tree-ring data and intrinsic water-use efficiency (WUEi) to quantify the post-fire responses of a tree (Pinus pinea) and a shrub (Juniperus phoenicea) in Mediterranean coastal dunes located in the Doñana protected area, SW Spain. We compared pines and junipers growing in an inter-dune slack with those growing in a nearby dune ridge. We quantified crown damage and bark char in pines impacted by a wildfire. Pines with lower crown damage after the fire showed a higher growth rate one year later. Growth decreased afterwards in the case of fast-growing pines from the slack site, whereas slow-growing dune pines showed increasing growth rates one to three years after the fire. The fire did not change the pines’ WUEi, whereas the junipers located in dunes presented the highest WUEi values. Severe crown damage (damage > 60%) impairs long-term growth recovery in P. pinea. Open and heterogeneous landscapes can reduce the wildfire risk in the study Mediterranean area, where slack vs. dune and tree vs. shrub differences should be considered in post-fire management plans.

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• Lightweight and normal weight aggregate reinforced-concrete beams were subjected to ambient and elevated temperatures. • Lightweight aggregate beams demonstrated better seismic performance at high temperatures. • The dissipated energy varied by the concrete type and the heat exposure level. • RC beams incorporating LECA can safely be implemented in structures subjected to seismic loads. • The finite element analysis can accurately simulate the seismic behavior of RC beams after exposure to high temperatures. The stringent demand for designing fire-resistant structures in recent years has triggered a good deal of effort into theoretical and experimental studies. Structures may be exposed to seismic loading after a fire in the course of their lifetime, resulting in the reduction of their integrity. This study examines the seismic performance of damaged light weight aggregate reinforced concrete beams by exposure them to elevated temperatures. Accordingly, a set of 8 light weight and normal weight concrete prisms were cast and tested under quasi-static reversed cyclic loading after exposure to temperatures of 25, 250, 500 and 750 °C. The stress-strain relationship, residual deformations, strength and stiffness degradation, energy dissipation capacity and cracking pattern of light weight beams were compared to those of the normal weight counterparts. The experimental results revealed that the light weight beams, although with lower compressive strength at ambient temperatures, show better seismic performance when exposed to elevated temperatures as compared to their normal weight companions. On this account, the residual deformations of the entire set of beams decreased with increasing the thermal exposure level. However, this was less pronounced in the case of lightweight prisms. In addition, the energy dissipation capacity of normal weight prisms was higher than that of the lightweight beam specimens at ambient temperature. Nonetheless, the dissipated energy in lightweight concrete overtook that of normal weight concrete as the temperature was increased. Moreover, the beams under investigation were numerically modeled in OpenSees through fiber section models in order to verify the obtained experimental results. The fire effect was applied in the compressive strength reduction of the beam specimens based on experimental results, such that each heat-exposure level relatively decreased the compressive strength of prisms. The results confirmed that the numerical responses obtained from material models in OpenSees could provide the characteristics of the beam capacity as well as the strength and stiffness degradation behavior in good accord with the experimental results. [ABSTRACT FROM AUTHOR]