Case Studies for Construction /Structural Engineering Industry

Examples of SR&ED eligible activities that may normally be overseen:

1. Experimentation was conducted to develop an understanding for how load transfer influences light diffraction of etched overlapping photographic images in glass.
   
   Glass etching has been used in image presentations for centuries, where increased definition and 3-dimensional appearance can be achieved with greater etching depth. Past examples have been relatively small, simple figures. The conflict is that with increased image size and detail, it involves greater dead loads and etching depths, potentially leading to the tensional forces exceeding the glass limitations, resulting in explosive failure. Increasing glass thickness for improved robustness also increases the loads and influences the light diffraction patterns. The claimant studied how the loads will transfer as the etching depth increases, while attempting to achieve the diffraction patterns and image clarity desired. This is beyond the present state of the industry knowledge. They sought to advance their knowledge of the interactions between light diffraction patterns and load distribution paths for a large glass panel display system having overlapping etched images
2. Experimentation was conducted to develop an understanding of load transfer paths involved in supporting heavy glass display panels on a curved drywall surface. The claimant had to develop a method to transfer the heavy glass loads (4,000 lbs.) to the curved drywall surface (approximate 50’ radius) without shearing the drywall or fasteners popping out. Though incorporating additional fasteners in drywall can better distribute the loads, the claimant was uncertain how the load can be transferred without damaging the drywall when the material limitations have been exceeded. Additionally, traditional cleat mounts cannot be used on a curved wall surface for attachment of large glass panels. Thus, they were uncertain what alternative attachment methods will allow for acceptable load transfer to the drywall without damage. In engineering design, drywall is not considered as a structurally supporting member, but rather only as a wall covering that can support very light loads. The team sought to advance their knowledge of load distribution paths within a drywall covering on a traditional stud wall with a significant curvature, for supporting heavy glass display panels.
3. Investigation was done to develop an understanding of the nature of elevated concrete and steel floor vibration characteristics resulting from occupancy footfall transmitted vibration within, and between floors; and to improve the accuracy of prediction.
   
   Standard prediction techniques were less than 50% accurate in describing the nature of the floor response resulting from footfall vibration. They were limited to predicting responses by a single source of excitation, at a specified location. They couldn’t reliably predict the natural frequency when the floor is irregular or when the frequency of excitation varies. The influence of factors such as harmonics, variable excitation frequencies, and mode of excitation, on different sections of the floor and on connecting floors is not well understood.
   
   Footfall-induced vibrations originating from walking in a corridor or other repetitive activities are transmitted to other areas of the floor and between floors (for example, vibration from an aerobic studio above a diagnostic lab). The magnitude of the vibrations in sensitive areas of the structure must be precisely predicted in order to mitigate vibrations that could exceed equipment design criteria. Stiffness is a critical parameter in vibration prediction. Structural configurations between floors can act as diaphragms, inducing unpredictable stiffness. An understanding of the effect of different structural configurations on stiffness and vibration characteristics, within and between floors, was required. Also, millions of scenarios must be considered in the model to produce an accurate characterization of the floor’s vibration. Analysis of the vast quantity of data had to be performed within a few minutes instead of hours. Knowledge of the parameters and their interaction necessary to nest several algorithms and achieve efficient processing was required.
4. To gain understanding of the nature of the force distribution and light diffusion characteristics of composite interior wall panels, covering large curvilinear wall surface, which provides a translucent, wood veneer appearance. Existing laminated wood veneers used for interior wall cladding have inadequate grain richness (depth and visibility), which quickly deteriorates with time. Solid wood will highlight the true richness of the grains, but cannot transmit light. This posed structural integrity issues which are compounded by the curvilinear nature of the wall to be covered. The rich wood appearance and light transmission can be achieved from a panel made of thin wood film, sandwiched between transparent supports. If the wood film is too thin, stress relief causes severe distortion (waviness) masking the richness of the wood grain, and the sections cannot be joined together without significant scrap. If too thick, it does not allow light transmission. The claimant sought to advance their knowledge of the effect of the nonlinear relationship between wood film thickness, wood characteristics (which vary with species, age and size), and processing parameter variation, on waviness and light transmission. Also, the film had to be supported by transparent material and the load on the support structure had to be limited. The team also sought to gain further insight into the effect of the combination of material characteristics, weight, and curvature on structural integrity and durability.