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Not all precast concrete structures show performance that can be obtained by experiment. Finite element analysis also plays a vital role in the study of structural performance. In this paper, a steel hysteretic is employed to reproduce the experimental response of a steel strand anchored precast concrete frame joints exposed to reversed cyclic load tests. The ultimate load and ultimate displacement obtained by finite element calculation are not more than 1% different from the experimental values. By employing the proposed model, the hysteretic curve, energy dissipation capacity, stiffness degradation, and displacement ductility of the reactive powder concrete (RPC) interior beam–column joints were analyzed. According to the analysis, in the case of the failure morphology of RPC beam-to-column joints with friction dampers, it is evident that the plastic hinge at the end of beam had shifted outward. In addition, both the energy dissipation capacity and the ultimate bearing capacity of the RPC interior beam–column joints have been improved, the ultimate load of PC2 is 28.8% higher than that of PC1. According to the aforementioned results, the parametric analysis of the RPC interior beam–column joint was performed. Subsequently, by varying the friction coefficient of the friction damper, the stirrup spacing in the panel zone and the different axial compression ratios, the influence of a number of different parameters on the mechanical properties of the joint was obtained.

Diallyl trisulfide (DATS), a sulphur‐containing compound isolated from the medicinal food plant garlic, has been previously reported to attenuate experimental colitis induced by either dextran sodium sulphate (DSS) or 2,4,6‐trinitrobenzenesulfonic acid (TNBS) in mice; however, the underlying mechanism remains to be identified. In this study, we deciphered the key mechanism by which DATS alleviates ulcerative colitis (UC). We showed that oral administration of DATS for 10 consecutive days greatly restrained the infiltration of macrophages and the pathological changes in colonic tissues of mice with DSS‐induced colitis. DATS treatment notably dampened the content of IL‐1β and IL‐18 and suppressed NLRP3 inflammasome activation in colon. Mechanistically, DATS effectively diminished the generation of ROS in macrophages. The suppressive effect of DATS on the activation of NLRP3 inflammasome and downregulation of IL‐18 and IL‐1β levels was blunted by xanthine oxidase. Further studies revealed that DATS inhibited NF‐κB pathway activation by suppressing the expression of Trx‐1, thereby inhibiting NLRP3 inflammasome activation. Trx‐1 overexpression and interference in macrophages promoted and diminished NLRP3 inflammasome activation, respectively. In summary, garlic and its main active ingredient DATS have potentials to prevent and treat UC, and DATS functions by inhibiting NLRP3 inflammasome activation via Trx‐1/ROS pathway. [ABSTRACT FROM AUTHOR]

In this study, we report the results of an experimental investigation conducted under a four-point bending loading in order to evaluate the shear performance of concrete beams reinforced with basalt fiber without web reinforcement. According to the experimental results, it is evident that the final failure morphology of concrete-basalt fiber concrete composite beams and conventional concrete beams was shear failure, whereas the failure morphology of concrete beams reinforced with full basalt fiber was bending failure. Moreover, the results also indicate that the cracking load and ultimate bearing capacity of concrete composite beams reinforced with concrete-basalt fiber are lower than those of conventional concrete beam. This is mainly due to the interface between ordinary post-cast concrete and concrete reinforced with hardened basalt fiber. Due to the superior tensile properties of fiber, composite beams and all basalt fiber concrete beams exhibit a higher degree of ductility than conventional concrete beams. Utilizing the existing calculation theory for concrete beams reinforced with fiber, it was calculated that the cracking load and ultimate load of basalt fiber beams were calculated, and the calculation results were consistent with the experimental results. Based on the results of the evaluation and the theoretical analysis, this study proposes a finite element modeling method for basalt fiber composite beams. The results of the analysis were consistent with the experimental results of all investigated beams. The established model was employed in order to investigate the influence of shear span ratio on the shear performance of basalt fiber beams.

The seismic performance index of prefabricated structures is generally obtained via experimental analysis. However, in experimental research, it is impossible that every influencing factor can be taken into account. Therefore, the finite element analysis method can be used as a supplementary method for experimental research to carry out parametric analysis of joints. Based on this test, a hysteretic model of steel bars is developed on the ABAQUS platform; meanwhile, the model is used to simulate the seismic analysis of the proposed local reinforced joints. The hysteresis curve obtained via simulation exhibits a high degree of coincidence with the experimental results. Based on the validated model, a detailed parameter analysis of prefabricated local reinforced concrete frame joints is carried out. The analysis results illustrate that the axial pressure ratio at the top of the column has a minimal impact on the joint's performance. Decreasing the stirrup ratio within the core region, enlarging the diameter of the PC steel bar, and increasing the concrete strength that is poured in the keyway and the core region can raise the cumulative energy consumption of the joints, thereby reducing the damage degree of other units and improving the maximum bearing capability of the joints. [ABSTRACT FROM AUTHOR]