Vol. 7 No. 2 (2024)

Open Access

Articles

Article ID: 607

Research on bridge safety early warning method based on strain energy theory and health monitoring data

by Yinghua Li, Xiaoqing Zeng , Yanxing Tang

Insight - Civil Engineering, Vol.7, No.2, 2024; 50 Views, 14 PDF Downloads

Bridges are technology-intensive and heavily invested permanent infrastructure. After completion and opening to traffic, bridge structures are easy to be affected by factors such as traffic load and atmospheric environment. Therefore, it is necessary to do safety warning and evaluation of bridges, especially the abnormal behavior in the early stages of bridge operation. In this research paper, a large-span continuous rigid frame bridge installed with the health monitoring system (HMS), of which a large amount of health monitoring data are collected by the HMS, is used as an example, and then a bridge safety early warning method is proposed when the bridge is during early operating period. First of all, the research finding that the internal stress of the prototype bridge obeys normal distribution through statistical analysis is used; next, we deduce that the strain energy inside the prototype bridge is subject to the Non-central Chi-square distribution combined with the strain energy and statistical theories; in the end, the key probability density distribution function of strain energy and its parameters are derived by using the key stress distribution function of the high performance concrete C50 strength grade used in the prototype bridge. The method recommended in this paper is conducive to the formulation of bridge preventive maintenance strategies.

Open Access

Articles

Article ID: 651

Important properties of central island and median island at roundabouts

by Kerim Hrapović

Insight - Civil Engineering, Vol.7, No.2, 2024; 61 Views, 23 PDF Downloads

The central island and median island are very important elements of a roundabout, which strongly influence the impact on traffic and safety of road users. The central island should be designed in such a way that it is perceived as an obstacle in the approach. At roundabouts with an outside diameter of more than 35.0 m, the central island should prevent the view from the approach road straight ahead to the opposite exit. This can be achieved with various design options such as trees in the central island. The layout of the central island should be customized to suit the particular local conditions. When designing the central island, it is important to factor in the requirements of buses, along with municipal and emergency vehicles. While aesthetics is a consideration, the geometric design of the intersection is a critical aspect in roundabout planning. If sufficient space is available after considering the turning radii of key vehicles, curbs can be used to define boundaries. Alternatively, paved island sections that allow partial or full traversal can be a viable option.

Open Access

Articles

Article ID: 650

Interaction between roadway and sewer/water pipes

by Kerim Hrapović

Insight - Civil Engineering, Vol.7, No.2, 2024; 47 Views, 13 PDF Downloads

Sewage pipes and drinking water pipes as well as all other pipes such as gas, district heating, electricity, internet, telephone, cable TV, etc. in densely populated areas are located in the road space. Over time, the traffic loads as well as the road structure can change. In addition, the materials of the pipelines are subject to ageing processes. The consequences of leaking drinking water and wastewater pipes that lie in the body of the road can have extremely negative effects. Firstly, the wastewater contains harmful substances that must not be allowed to enter the groundwater under any circumstances. Secondly, the leaking drinking water pipes, especially a water pipe burst, cause the soil mechanical changes in the subsoil and the traffic surface pavements and can cause immense damage in the road surface or in the road body itself.