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Summary: Traditional wooden structures are characterized by the presence of a column base that seems to be floated above the foundation stone. This study used pseudo‐static experiments to assess the seismic performance of flat pendulum floating resting columns, focusing on the decay and repair of the wood frame (WF). First, an artificial method was used to simulate fungal decay damage of column‐foot joints, and filling reinforcement was applied to the decayed column‐foot joints, and second, according to the design method in the Sung dynasty architecture, the Ying‐tsaofa‐shih (building standards). This study presents the findings of pseudo‐static tests that were conducted at Yangzhou University. Three 1:3.52 scaled specimen WFs with flat‐pendulum‐floating‐shelf (FPFS)‐typed (Ping‐bai‐fu‐ge) columns, i.e., non‐damaged WF (named after NT), considering the damaged WF (named after DF) and strengthening damaged WF (named after DR) with one‐way straight mortise‐tenon joints (OWSMT) joints were made and subjected to cyclic lateral loads during testing. The properties of the WFs with FPFS columns, such as the failure mode, hysteretic and envelope curves, strength and stiffness deterioration, and energy dissipation, have been studied. Finally, the effects of additional damage and reinforcement measures on the seismic performance of WFs are analyzed and compared with the finite element numerical simulation results. This research shows that damage to the column foot decreases the WF's seismic performance, although filler reinforcement may increase it. The foot and mortise joints are interconnected and interact in the wood frame's seismic stressing mechanism. Foot decay reduces the seismic performance of the foot joint, hence increasing the seismic energy dissipation activity of the mortise joints. [ABSTRACT FROM AUTHOR]

The present paper combined the natural environment excitation technology (NExT) with the eigen system realization algorithm (ERA) to identify the modal parameters of a suspension bridge. Firstly, the critical parameters in NExt–ERA, such as record length, window length, and ranks of the Hankel matrix, and their influence on identification accuracy have been discussed. Subsequently, based on the acceleration series obtained from the Xihoumen Bridge Health Monitoring System, 3015 sets of modal frequencies and modal damping ratios of the Xihoumen Bridge were identified under 7 sets of wind speeds by the NExt–ERA. Finally, the probability distribution and confidence interval of the structural modal damping ratios were analyzed. Besides, the dependence of identified frequencies damping ratios on wind speed was also discussed. The results show that at the same wind speed, the mean value, and variance of the torsional and lateral mode damping ratios are larger than those of the vertical mode, but this difference gradually decreases with the increment of wind speed. The modal damping ratios along three directions under different wind speeds all follow the generalized extreme value distribution, but wind speed affects the tailing properties of probability distribution of the vertical and torsional mode damping ratios. The estimated damping ratios could provide references for structural design and vibration control of similar long-span bridges. [ABSTRACT FROM AUTHOR]

A new method, the notched specimen cracking test (NSCT), is presented to directly measure the thermal stress and critical temperature of asphalt binders at low temperatures. The NSCT contains a notched specimen that contraction deformation is limited by special invar steel fixtures exposed to a continuous cooling temperature field provided by a programable environmental chamber. To simulate the actual thermal contraction state–strain level of asphalt pavement in the laboratory, the geometry of the binder specimen was carefully designed by theoretical computation based on the superposition principle. The preliminary test result shows that NSCT for evaluation of the potential cracking risk of modified or non-modified binders at low temperatures is reliable and easy to operate. The coefficient of variations of thermal stress results is at least 50% smaller than the traditional thermal cracking measurement method. [ABSTRACT FROM AUTHOR]

The particle damper has been widely used as an efficient passive vibration control device in recent years. The highly non-linear characteristic of the energy dissipation mechanism is essential for our increased understanding of non-obstructive particle damper (NOPD). To connect motion modes of the granular system and energy dissipation, we developed a neural network using simulated annealing backpropagation (SA-BP) to predict the loss factor of NOPD in this paper. The simulations based on the verified discrete element method (DEM) model are carried out, and the data is used to train and test the neural network. Based on the prediction of a well-trained neural network using SA-BP, the relationship between the loss factors and the rheology behaviors of the granular system is discussed. This paper effectively combines intelligent algorithms (SA-BP) and particle damping characteristics. The algorithm is expected to be further used as an auxiliary method for the experimental study of the granular system. [ABSTRACT FROM AUTHOR]

The physical property and expansion rate of the modified steel slag were tested. The mineral composition and microstructure of steel slag were analyzed by XRD, XRF and SEM. Three kinds of asphalt mixtures with AC-13C(modified steel slag, original steel slag and limestone) were designed. The road performance of asphalt mixture was evaluated through immersion marshall and high temperature rut tests. The results show that comparing with the control group, the water-immersed expansion rate of the modified steel slag reduces to 1.69%, and the volume expansion rate of the modified steel slag asphalt mixture reduces to 0.4%. After the modification of steel slag by chelating agent, CaC2O4 is generated on the surface and pores of steel slag. The physical property of modified steel slag and the basic road performance of asphalt mixture are improved, which are better than those of limestone asphalt mixture. The modified treatment can eliminate f- CaO in steel slag, and CaC2O4 protective layer can be formed on the surface of the modified steel slag, which can reduce the expansion rate of steel slag and improve the mechanical property. [ABSTRACT FROM AUTHOR]

Objective: Because of the high costs associated with early‐stage laryngeal carcinoma diagnosis and prognosis prediction, this study attempts to find valuable targets to establish a novel predictive model by focusing on the aldehyde dehydrogenase 2 (ALDH2) genotype and other peripheral blood markers. Study Design: Retrospective study. Setting: Tertiary comprehensive hospital. Methods: From January 2011 to January 2021, 362 cases of laryngeal carcinoma were included and divided into 2 groups in this retrospective analysis. Information on medical history, alcohol, and tobacco consumption habits, ALDH2 genotypes, and other peripheral blood markers was collected. Endpoints of the current study included disease‐free survival and overall survival. A nomogram model for overall survival was established and evaluated using receiver operating characteristic (ROC) curves. Results: A total of 236 patients were included in the training cohort, and the other 126 were included in the validation cohort. The median follow‐up of the patients was 9.6 years (interquartile range: 7.5‐12.5 years). Peripheral fibrinogen, hemoglobin, and ALDH2 genotypes were significantly associated with an increase in laryngeal carcinoma mortality rate on Kaplan‐Meier curves. The ROC curve showed that the effectiveness of overall survival prediction by the nomogram model was better than that of traditional clinical staging. Conclusion: A prognostic nomogram of laryngeal carcinoma patients involving ALDH2 and peripheral blood markers and T and N stages was constructed and validated. [ABSTRACT FROM AUTHOR]