Calculation of large-span glulam structures as a soil base-foundation-above-ground structure system

Abstract

The object of research. Long-span glulam arches are widely used as coatings for public and sports buildings. The studies carried out concern double-hinged segmental arches with spans of 60 m and more. Description of the problem. The study of the peculiarities of the work of arches as a system "soil base - foundation - above-ground structure" is associated with the significant influence of uneven deformations of supports on the stress-strain state of the above-ground structure. A change in the stress-strain state in the structure itself, associated with uneven deformations of the foundations, can lead to a significant decrease up to the complete exhaustion of the bearing capacity Main scientific results. This article provides an analysis of the change in the stress-strain state of glulam arches when calculating the system "soil base-foundation-above-ground structure". It is noted that non-uniform deformations of supports have the greatest influence on the stress in the support zones of the structure. The range of critical non-uniform subsidence has been determined, which should be limited when calculating and designing the foundations of large-span arches. It has been confirmed that double-hinged glulam arches work well in conditions of uneven subsidence due to the peculiarities of the design scheme. The results of the studies carried out and the recommendations provided will significantly improve the reliability of large-span structures and require mandatory inclusion in the current practice of calculation and design. In addition, additional requirements for the distance between mine workings for large-span structures should be introduced when performing engineering and geological surveys. This distance should be reduced for a clearer account of the deformability of the foundations for columnar foundations, and the number of workings should be increased. The area of practical use of the research results. The cross-section of the glulam arches is selected taking into account additional deformations of the supports, making it possible to avoid unpredictable damage to the structure during operation. Innovative technological product. Glulam arches, the cross-section of which is determined taking into account additional deformations from uneven subsidence of the supports Scope of application. Glulam arches calculated in this way can be used as covering for public and sports buildings for various purposes.