Effect of structural design on traffic-induced building vibrations

Population growth and urbanization results in densified cities, where new buildings are being built closer to existing vibration sources, and new transportation systems are constructed closer to existing buildings. Potential disturbing vibrations are one issue to consider in planning urban environments and densification of cities. Vibrations can be annoying for humans but also for sensitive equipment in, for example, hospitals. In determining the risk for disturbing vibrations, the distance between the source and the receiver, the ground properties, and type and size of the building are governing factors. In the paper, a study is presented aiming at investigating the influence of various parameters of the building’s structural design on vibration levels in the structure caused by ground surface loads, e.g. traffic. Parameters studied are related to the type of construction material (if it would be a light or heavy structure), and to the slab thickness. The study is limited to the structural response at frequencies near the first resonance frequency of the soil. The finite element method is employed for discretizing the building structure that is coupled to a semi-analytical model considering a layered ground

Variation in models for simple dynamic structure–soil–structure interaction problems

To account for dynamic cross-coupling of structures via the soil, a computational model must be accurate enough to provide the correct overall behaviour of the scattered wave field. However, simplicity is also important when a model should be used for design purposes, especially in the early design stages and feasibility studies. The paper addresses the accuracy of simple models in which an array of structures is simplified into blocks placed on the ground surface or embedded within the soil. Comparisons are made between models that account or do not account, in a proper manner, for the inertia and embedment of the structures. Especially, the limitations of simplified models are discussed regarding their capability to quantify the insertion loss accurately

Influence of Plastic Dissipation on Apparent Fracture Energy Determined by a Three-Point Beding Test

A three-point bending test used for determining the fracture energy in modus I for wood perpendicular to the grain is studied, If the height of the specimen is varied, the results show a size effect, The specimens used in testing have been analyzed by finite element calculations with an anisotropic elasto-plastic material model in order to determine the influence of plastic dissipation. Analysis has been performed for three sizes of specimens where the height and length have been varied. The computational results are compared with experimental results

Experimental and numerical determination of the hygroscopic warping of cross-laminated solid wood panels

The moisture-induced warping of three-layered cross-laminated solid wood panels made of Norway spruce was studied. The panels were exposed to different climate conditions at 65% and 100% relative humidity at the two panel faces. The results showed increasing cup deformation with an increasing relative thickness of the outer layers. The annual growth ring orientation was found to have a significant influence on the magnitude of the cup deformation. Measurements and numerical simulations of the moisture distribution within the panel were made in order to provide data for numerical simulations of the warping. A distinctive moisture profile with a conspicuous influence of the adhesive bond lines was found. The coefficient of diffusion of the adhesive bond lines was determined from the measurements and simulations. The mechanical material model used for the warping simulations takes into account elastic strain, moisture-induced swelling, and mechano-sorptive strain. The simulations showed good agreement with the warping test results. The most important material parameters for the cup deformation, which were identified in a parametric study of a panel with vertically oriented annual rings, are the moduli of elasticity and the swelling coefficients in the longitudinal and radial direction. Furthermore, the mechano-sorptive coefficient in radial direction was found to have a significant influence on war

Structural Behaviour of Glass Panels Under Soft-body Impact

Glass is a commonly used material in modern architecture not only for building enclosures but also for glazed barriers preventing building occupants from falling out of balconies or different levels inside buildings. The paper reports some results of an on-going research project involving testing of glass balustrades and infill panels mounted with different fixing methods, such as linear clamps, local clamp fixings, and point fixings through holes in glass. A reduced numerical model for prediction of strength of glass under soft body impact is also presented. In the experimental study toughened and heat-strengthened glass, as well as two interlayer materials of different stiffness, were used

Structural Analysis of Slender Glass Panel Subjected to Static and Impact Loading

Slender glass panels are widely used as storefronts and indoor separating walls in shopping malls and public buildings. To ensure that the design and construction is technically safe for general use and that it meets current and accepted technical standards, in-situ testing is required by the building administrator or authorities. A case study was performed of an indoor glass lantern in a public building made from slender two-side supported glass panels with a complex geometry. It provides structural assessments and results of in-situ experiments including static loading and soft body impact test. Results from numerical simulations of impact loading on the glass panels complementing the experimental results are also presented. The in-situ testing proved that the structural design meets current standards regarding the static loading. The soft body impact test proved the safety of the intact panel and the panel with one ply deliberately broken. The numerical study showed that, for a more complicated geometry, the stress distribution can dramatically change over time and that stress concentrations can develop at certain locations at a late stage in the impact history