Current Issue : April-June Volume : 2023 Issue Number : 2 Articles : 5 Articles
The detailing of a structure is completed in order to carry out proper construction and provide the necessary details needed for ductility and failure prevention through various design parameters and standards. Ductility refers to a reinforced concrete member’s capacity to withstand significant deflection before failing. This property of reinforced concrete is important since it predicts failure and helps to avert overall destruction and failure. This is specifically true in earthquakeprone areas. For structural detailing, many design regulations and detailing guidelines are utilized. Reviewing the nonseismic and seismic details of RCC area elements is the primary purpose of this research article. Discussion on the potential of BIM tools in the structural detailing of area elements is carried out, along with a review of the literature and interviews with structural engineers. For BIM tools, the nonavailability of specific features was highlighted as a barrier to helping with the automation of selecting rebars for RCC area elements. We conclude with an overview and a comprehensive description of several features of seismic and nonseismic RCC area elements. Additionally, emphasis is given to the BIM tool’s recent breakthroughs regarding structural aspects....
Automated vibration-based structural health monitoring (SHM) strategies have been recently proven to be promising in the presence of aging and material deterioration threatening the safety of civil structures. Within such a framework, ensuring high-quality and informative data is a critical aspect that is highly dependent on the deployment of the sensors in the network and on their capability to provide damage-sensitive features to be exploited. This paper presents a novel data-driven approach to the optimal sensor placement devised to identify sensor locations that maximize the information effectiveness for SHM purposes. The optimization of the sensor network is addressed by means of a deep neural network (DNN) equipped with an attention mechanism, a state-of-the-art technique in natural language processing (NLP) that is useful in focusing on a limited number of important components in the information stream. The trained attention mechanism eventually allows for quantifying the relevance of each sensor in terms of the so-called attention scores, thereby enabling to identify the most useful input channels to solve the relevant downstream SHM task. With reference to the damage localization task, framed here as a classification problem handling a set of predefined damage scenarios, the DNN is trained to locate damage on labeled data that had been simulated to emulate the effects of damage under different operational conditions. The capabilities of the proposed method are demonstrated by referring to an eight-story shear building, characterized by damage states possibly located at any story and of unknown severity....
In the ground of the preliminary study of the Taihangshan Mountain Tunnel, it was observed that under water-rich conditions, the long rolling of heavy-haul trains would deteriorate the surrounding rock, thereby causing damage to the bottom structure. Combined with data from long-term field monitoring and discrete element analysis, after clarifying the law of bedrock deterioration, the Fuyingzi Tunnel of Zhangtang Railway in China is taken as the research object of fatigue damage. ANSYS Workbench simulation software was used to compare further and analyze the influence of three characteristic deterioration stages of the surrounding rock on the basement structure damage. Based on the results, when the surrounding rock is intact, the basement structure gradually damages and expands from top to bottom, and the structural minimum fatigue life is approximately 76 years. When the surrounding rock is a partial cavity, the damage to the bottom structure intensifies and develops toward the surrounding rock’s deterioration position. The minimum fatigue life of the structure is 67 years, which decreases by 11.8%. When the surrounding rock is a cavity and connected, the damage of the bottom structure develops downward to a certain extent, which causes the structural damage at the deterioration position of the surrounding rock to develop in the opposite direction, i.e., from bottom to top. The structural minimum fatigue life is 42 years, which is reduced by 44.7% in the better situation....
Three-dimensional finite element model of the wood structure-foundation of the North House’s main hall in Tianshui under ground traffic excitation was established, and the damage of the first-floor longitudinal beam of the wood structure was simulated by the finite element method. The node acceleration response signals on beams were decomposed with a wavelet packet. The wavelet packet energy curvature difference index was proposed to determine the structural damage location. The results show that the wavelet packet energy curvature difference can decide the damage location of the middle part of the first-floor longitudinal beam, and the index value increases with the increase of damage degree. If SNR is 40 db or larger, the damage index can accurately identify the damage of ancient wooden structures. When SNR increases, the damage index will have an increasingly higher sensitivity and certain ability to resist the effect of noise. The function relation between the damage index and the damage degree is obtained to determine the structural damage degree. The study results provide a theoretical basis for the damage diagnosis of the wood structure of ancient buildings along the traffic line....
In this study, models for calculating the cracking load and a peak load of the UHPC-NC structures are established. The effects of UHPC’s high tensile strength, reinforced steel bars in NC, reinforce steel bars in UHPC, and prestress tendons in UHPC on cracking load and peak load are considered. In the cracking load model, UHPC is considered to be elastic and the stress distribution is triangular, the stress of steel bars and prestressing tendons is also calculated according to the plane section assumption and elastic theory. In the peak load module, UHPC is assumed to be partially elastic and partially plastic. The plastic part is represented by a rectangular stress block diagram, and the stress value reduction factor and rectangular stress frame height reduction factor are obtained by trial calculation. Compared with the experimental data of UHPC-NC beams with different types of combinations collected from references, the calculated results have a high matching degree, which is suitable for various types of UHPC-NC, both cracking loads and peak loads....
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