A moving impulse load generated by a heavy cogwheel can be used as a testing excitation for bridges. This novel type of dynamic load acts along the entire driving path, its intensity is adjustable, and it can be very efficient in the case of resonance. Verification tests were performed on a model under laboratory conditions and compared to numerical simulation. The results are extensively discussed.

The purpose of this article is to compare two predictive methods of J integral assessments for center-cracked plates, single-edge cracked plates and double-edge cracked plates produced from X52 and X70 steels, and a longitudinally cracked pipe produced from X70 steel. The two methods examined are: the GSM method and the J_s procedure of the French RCC-MR construction code, designated here as the FC method. The accuracy of J integral predictions by these methods is visualized by comparing the results obtained with the “reference” values calculated by the EPRI method. The main results showed that both methods yielded similar J integral values, although in most cases, the GSM predictions were slightly more conservative than the FC predictions. In comparison with the “reference” values of the J integral, both methods provided conservative results for most crack configurations, although the estimates for cracks of a relative length smaller than 1/8 were not found to be so conservative. The prediction of burst pressures for external longitudinal semielliptical part-through cracks in X70 steel pipe showed that the magnitudes of predicted burst pressures came very close to each other, and were conservative compared to FEM (finite element method) calculations and experimentally determined burst pressures.

Designing the modification of buildings for a new use is a costly and time-consuming process, before which it is often necessary to conduct a preliminary assessment of the feasibility of the intended project. The article discusses the procedure for such a preliminary cost-effective assessment using the example of a historic building with vaulted ceilings. For older historical buildings, archival documents specifying their geometry, construction details and material characteristics are typically not available. For the preliminary design, it is possible to obtain information about the dimensions of the load-bearing elements non-destructively. However, the knowledge of the exact material properties of the masonry exceeds the possibilities of an inexpensive assessment, which must take advantage of the data available in the literature for similar structures. This article presents a methodology and an example of the measurement and assessment of the mechanical response of the Baroque vault to static loading. It shows the process of obtaining data on the geometric shape of the structure by means of geodetic surveying and geometric radar measurements of the thickness of vaults whose upper faces are not accessible. Two models are used to calculate the internal forces in the structure. The first planar model considers a simplified barrel vault strip according to the focused geometry with respect to geometric nonlinearity and without tension, the second model is a linear spatial model of the entire vault. The calculation was performed in ANSYS 17.2, the input parameters of the material are taken from the literature. The calculated stresses in the vault are compared with the values of the design strength of brick masonry, taking into account the characteristic compressive strength of the masonry based on published known data obtained during tests of similar historical materials. The results are then used to decide on the feasibility of the intention to adapt the building for a new use.

The performance of a few localization schemes using measured mode shapes was tested in an experimental case study with respect to the Ultimate Limit State (ULS). The first question to be posed was: Is it possible to indicate and locate damage under laboratory conditions before the ULS is reached? Relatively simple localization criteria were chosen, which do not require extensive FE analysis. A new combination of them, designated here as Combined Localization Criterion (CLI), was proposed that performed well in the presented case. A simple supported beam with the damage progressing in three consecutive stages was used for the experiments. Mode shapes in the range of up to 100 Hz were extracted from the response of the structure to the air stream.