EXPERIMENTAL STUDY OF PLATES FOR PUNCHING UNDER DYNAMIC LOADING

the issues of strength and deformability of reinforced concrete floors during punching remain insufficiently studied at present, despite the available publications in the technical literature. This article presents the results of experimental studies on punching of fragments of conjugation of flat reinforced concrete monolithic slabs with a column under dynamic loading. The purpose of these studies was to obtain experimental data on the stress-strain state of a fragment of a monolithic floor during dynamic punching with varying thickness and class of concrete, to reveal the failure patterns of experimental samples, and to obtain new experimental data. A setup for dynamic testing is described. Comparison of breaking load for specimens tested under dynamic loading with breaking load for specimens tested for static load is presented. The angles of inclination of the punching shear pyramid under static and dynamic loading are indicated.

Impact of Load Retention on Aircraft Engine Parts Under Real Flight Cycle Conditions in Service Life Monitoring

One of the major problems in the development of algorithms for monitoring the life of aircraft gas turbine engines is that the character of loading in real flight cycles is crucially different from the character of the static and dynamic loading during the testing of samples. This paper proposes a method for taking into account the effect of retentions at maximum stresses and cycle temperatures on the low-cycle fatigue (LCF) of the heat-resistant alloys used in engine parts. Regularities in repeated-static loading (RSL) are used in combination with the method of linear accumulation of damage due to the LCF and RSL, with retentions of a variable length. A non-linear equation is derived for the summation of these damages, the solution of which determines the durability (life) of the part while taking into account the retention duration. The theoretical results were verified by using the experimental characteristics of the GS-6K and EI-437B nickel-based alloys, previously reported by other researchers.

Toe Support Pattern as a New Predictive Factor Associated with Falls in Older People with Psychiatric Disorders

Background Maintaining autonomy is one of the principal objectives for seniors and people with psychiatric disorders. Podiatric medical care can help them maintain autonomy. This work aimed to characterize and quantify the support of the toes in a psychiatric population by analyzing the influence of psychotropic medications and toe and foot support parameters on the prevalence of falls. Methods We conducted a cross-sectional descriptive study in 67 participants (31 people with psychiatric disorders and 36 without diagnosed disorders [control population]). Toe support pattern was analyzed with a pressure platform. Variables were measured in static and dynamic loading and related to falls and psychotropic medication use. Results The psychiatric population fell more than the control population and presented less toe-ground contact in static measurements, although it has more foot-ground contact time. Maximum toe pressure during toe-off is also less intensive in the psychiatric population and is related to people who take psychotropic medications. Conclusions Toe support pattern could be used as a predictive factor for falls and to improve stability in these populations.

Development of Smart Sensing Technology Approaches in Structural Health Monitoring of Bridge Structures

In recent years, immense development in Structural Health Monitoring (SHM) of bridges helps address the life span and reliability of bridge structure at contrasting phases of their service life. This article provides a detailed understanding of bridge monitoring, and it focuses on sensors utilized and all kinds of damage detection (strain, displacement, acceleration, and temperature) according to bridge nature (scour, suspender failure, disconnection of bolt and cables, etc.) and environmental degradation under static and dynamic loading. This paper presents information about various methods, approaches, case studies, advanced technologies, real-time experiments, stimulated models, data acquisition, and predictive analysis. Future scope and research also discussed the implementation of SHM in bridges. The main aim of this research is to assist researchers in better understanding the monitoring mechanism in bridges.