KUBA is a large civil engineering infrastructure management project that was investigated by Swiss Federal Roads Authority (FEDRO). The project was managed by CADRZ, with the underlying model and algorithms defined by IMC. It has been divided into a number of smaller projects. One of those smaller projects, appointed as KUBA ST, that 3ort inženjering was responsible for, concerned estimation of a bridge capability to be crossed over by a exceptional transport based on the bridge technical characteristics, its code of practice and characteristics of the exceptional transport.
In order for KUBA ST to provide comparative values for the maximum stress levels in relation to the exceptional transport and principal standard travelling loads, the bridge should be modeled as a superstructure, a task done by a civil engineer. The superstructure is broken down into a series of simple beams with characteristic spans, and principal cross-section widths for the passage over the bridges.
An exceptional transport is defined by an articulated truck transporting a particularly heavy load. The exceptional transport is represented by a load model, consisting essentially of a series of vertical concentrated forces.
The KUBA ST program provides comparative values for the maximum stress levels in the main superstructure in relation to the exceptional transport and principal standard travelling loads for the bridges. These comparative values form the basis for the final assessment of the crossing possibility. The determination of the comparative values is based on a simplified basic system, in order to reduce the information concerning the bridge superstructure down to essential data. The comparative values indicate the ratio of the maximum strain and stress levels on the main superstructure in relation to the exceptional transport and respective values according to the selected standard travelling loads. For comparative values up to and including 1.00, the reserves are adequate, as far as the structural safety and strains are concerned.
KUBA ST 4.0 was developed in tight correlation with the other KUBA 4.0 projects, and was heavily relied on a framework specially created for this purpose by CADRZ. Program was written in C# and developed with MS Visual Studio 2005. It was designed as a web service consumed by a windows forms application. During development, software was documented as required by CADRZ using UML (Unified Modeling Language) 2.0. Since this project exceeded capabilities of our permanent staff at that time, a software company from Belgrade was engaged to work on the project with us and under our leadership.