Bulletin of the Transilvania University of Brasov. Series I - Engineering Sciences

R Computer Program for The S2 Control Chart

Nicolae Eftimie — 2025-04-09

To monitor the process variability, the s chart is frequently used. However, the center line of this chart is not an unbiased estimator of the process standard deviation. To avoid this problem, the s² chart may be used instead of the s chart because its center line is an unbiased estimator for the process variance. The paper presents the conceiving of a computer program for the s² chart. The program is developed by means of the R language. After presenting the way in which the program was developed, the paper presents the results obtained after running it.

Carbon Fibre Reinforced Polymers Applied in Steel Structures for Improving Fatigue Behaviour - A Short Review

C. Bratu — 2024-04-09

Fatigue is a critical issue in structural engineering, characterized by the sudden and often catastrophic failure of elements subjected to cyclic loading, which can lead to significant material damage and loss of life. Carbon Fibre Reinforced Polymers (CFRP) composites is a promising alternative to traditional reinforcement methods, offering a direct, efficient, and cost-effective means to improve fatigue strength and repair damaged steel members. This paper provides a short literature review on the current advancements in the rehabilitation of steel structures, focusing on the application of CFRP for structural reinforcement. Key topics include the mechanical properties of steel and Fibre-Reinforced Polymer (FRP) composites, the bond characteristics between FRP and steel members, the fatigue performance of aged steel structures, and the current state of design codes and guidelines pertinent to FRP applications. Testing approaches from various research efforts are also examined in order to offer insights into current practices. The review highlights CFRP's economic and practical advantages, such as reduced costs for strengthening aging structures, shortened repair timelines, the ability to extend the lifespan of culturally and historically significant structures, and FRP's suitability for retrofitting steel structures due to its excellent strength-to-weight ratio and resistance to corrosion. The ease of on-site application and the low impact on traffic flow during repairs further enhance its appeal, especially for emergency repairs.

The Insert of a Reduced-Gauge Tunnel in a Crowded Intersection in Iasi

N.I. Galusca — 2025-04-09

In the past two decades, Iasi City had an accelerated pace of development on the number of inhabitants, the number and complexity of some industrial and commercial units, and also on the higher education institutions. Although there has been made several street network modifications and the modernization of some traffic arteries, the explosive growth in the number of vehicles made the urban roads to not face the traffic flows requests.

Determination of Centers of Weight through the Analytical Method and Validation of the Results through the C# Programming Language

R.M. Bleotu — 2025-04-09

This paper focuses on the development and implementation of an analytical method for determining the centers of gravity of complex bodies. Through this process, the aim is to obtain an accurate and efficient solution for determining the center of gravity in a practical and easy-to-achieve way. The paper includes a detailed presentation of the analytical method used, including the algorithms and mathematical formulas involved in determining the center of gravity for various types of complex bodies. It also examines how this method can be implemented in the C# programming language to allow validation of the results obtained from the analytical calculation.