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Tensegrities are pin-jointed frameworks consisting of discontinuous compressive struts held within a tensioned cable net. Existing in a state of self-equilibrium, tensegrity structures can be found in vary-ing states of rigidity dependent on the initial pretension existing within the cables. The current state of tensegrity understanding appears comprehensive, and yet, tensegrities appear to be relegated to a class of architectural sculpture, due to the complexity associated with understanding their behaviour. This com-plexity is often attributed to the lack of application for tensegrity structures within the built environment. For this reason, this thesis aims to examine the effect of compressive loading on tensegrities, and how different pretensions, geometries and materials aid in resisting this applied loading. A review was conducted to determine a current understanding of load bearing tensegrity structures. Through conducting this review, it was found that stiffness and load bearing capacity directly correlate with the level of applied pretension. A computer model was developed using Rhinoceros 3D and Grasshopper (in conjunction with K2Engineering analysis software) to confirm this result. Iterative form-finding was utilised to determine resultant geometry (dependant on initial pretensions and applied loads), which was subsequently used to obtain axial loads within each member of the tensegrity.

Carbon nanofibers (CNFs) were directly synthesized on Portland cement particles by chemical vapor deposition. The so-produced cements contained between 2.51–2.71 wt% of CNFs; depending on the production batch. Several mortar mixes containing between 0 and 10 wt% of the modified cement were produced and the electrical properties at various ages and the load sensing capabilities determined. The percolation threshold related to the electrical conductivity was detected and corresponded to the amount of the present CNFs, 0.271, 0.189, 0.135 and 0.108 wt%. The observed threshold depended on the degree of hydration of the Portland cement. The studied mortars showed a strong piezoresistive response to the applied compressive load reaching a 17% change of the electrical resistivity at an applied load of 3.5 MPa and 90% at 26 MPa. This initial study showed that the studied material is potentially suitable for future development of novel fully integrated monitoring systems for concrete structures., Validerad;2019;Nivå 2;2019-04-15 (oliekm)

The results of experimental researches of deformation character of construction as truncated pyramid with additional stiffening plate at compressing loadings are given. Stiffening plate influence on organization of the purposeful construction crush process with the purpose of their energy absorption properties increase is determined., Приведены результаты экспериментальных исследований характера деформирования конструкций в виде усеченной пирамиды с дополнительными ребрами жесткости, расположенными по периметрам ее поперечных сечений, при сжимающих нагрузках. Определено влияние ребер жесткости на организацию целенаправленного процесса смятия конструкций с целью повышения их энергопоглощающих свойств., Приведено результати експериментальних досліджень характеру деформування конструкцій у вигляді усіченої піраміди з додатковими ребрами жорсткості, розташованими по периметрах її поперечних перерізів, при стискальних навантаженнях. Визначено вплив ребер жорсткості на організацію цілеспрямованого процесу зминання конструкцій з метою підвищення їх енергопоглинаючих властивостей.

The scope of the series covers the entire spectrum of solid mechanics. Thus it includes the foundation of mechanics; variational formulations; computational mechanics; statics, kinematics and dynamics of; rigid and elastic bodies; vibrations of solids and structures; dynamical systems and chaos; the theories of elasticity, plasticity and viscoelasticity, composite materials; rods, beams, shells and membranes; structural control and stability; soils, rocks and geomechanics; fracture; tribology; experimental mechanics; biomechanics and machine design., Prepared in cooperation with Univ. of Waterloo, Dept. of Civil Engineering, Waterloo, Ontario, Canada; Univ. College, Dublin, Ireland.