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This thesis presents the development and the seismic performance evaluation of steel MRFs with nonlinear replaceable links. Although existing MRFs can provide life safety during a design level earthquake, they are expected to sustain significant damage at the locations of flexural yielding fuses in the beams. The design of the fuse is also interlinked with the design of the beam, often resulting in over-design. These drawbacks can be mitigated by introducing replaceable links at the locations of expected inelastic action. Four full-scale beam-to-column subassemblages with two link types were tested under cyclic loading: i) double channels with bolted web connections, ii) W-sections with bolted end plate connections. The experiments demonstrated that MRFs with replaceable links can provide strength and ductility equivalent to existing MRFs. Finite element models were then developed to capture the observed experimental responses, including local buckling, bolt slipping, and bolt bearing. Finally, preliminary design guidelines were proposed.

This thesis presents the development and the seismic performance evaluation of steel MRFs with nonlinear replaceable links. Although existing MRFs can provide life safety during a design level earthquake, they are expected to sustain significant damage at the locations of flexural yielding fuses in the beams. The design of the fuse is also interlinked with the design of the beam, often resulting in over-design. These drawbacks can be mitigated by introducing replaceable links at the locations of expected inelastic action. Four full-scale beam-to-column subassemblages with two link types were tested under cyclic loading: i) double channels with bolted web connections, ii) W-sections with bolted end plate connections. The experiments demonstrated that MRFs with replaceable links can provide strength and ductility equivalent to existing MRFs. Finite element models were then developed to capture the observed experimental responses, including local buckling, bolt slipping, and bolt bearing. Finally, preliminary design guidelines were proposed.

Blat, or the exchange of favors among friends, played a key role in the Soviet Union. The ability to use connections to gain access to hard-to-find goods or services was practically indispensible in the shortage economy. But blat has also been important in the post-Soviet environment, particularly in business. People with powerful connections have achieved success, while those outside of the business networks have been left behind. Thus, the ability to establish and maintain connections determines who succeeds in Russian business today. I argue that this dynamic significantly disadvantages foreign businesses in Russia because it favors insiders, is difficult for foreigners to understand, and most importantly, leads foreign companies into ethically questionable practices that are unacceptable in international business. Using the case of IKEA’s experiences in the Russian market, I hope to investigate whether this theory can inform our understanding of foreign businesses’ experiences in Russia.

Cold-formed steel structural members are used extensively in building construction, with a common application being wind load bearing steel studs. The studs frame into horizontal steel track members at the top and bottom of the wall assembly, with the stud-to-track connection typically being made with self-drilling screws or welds. The wall studs are designed to carry lateral loads only and must be checked for web crippling at the end reactions. While a design expression currently exists for the single stud-to-track connection, there is no similar design expression for multiple jamb stud members. An experimental investigation was carried out, consisting of 94 jamb stud assembly tests subjected to end-one-flange loading. The stud-to-track connections consisted of single C-section studs located at the end of a track simulating a door opening, and a built-up jamb made up of two studs simulating framing at either a window or door opening. The members were attached to the track with self-drilling screws. The research objective was to determine the failure modes and develop a design expression for these structural assemblies. The scope of the experimental investigation covered the following range of parameters: i) Stud and track depths of 92 mm and 152 mm; ii) Stud and track thickness (0.84 mm, 1.12 mm, 1.52 mm and 1.91 mm); iii) Configuration of jamb studs (back-to-back, toe-to-toe and single); iv) Location of jamb studs in the track (interior and end); v) Screw size (#8, #10 and #12); vi) Screw location (both flanges and single flange). Based on the findings of this investigation, design expressions are proposed to predict the capacity of this connection for two limit states: web crippling of the jamb stud; and, punch-through of the track. The web crippling design expression was taken from the North American Specification for the Design of Cold-Formed Steel Structural Members [AISI 2007a; CSA 2007] with new coefficients developed from the test data of the jamb stud-to-track assemblies. A new design expression is also proposed for the track punch-through failure mode, which differs from the approach currently used in the North American Standard for Cold-Formed Steel Framing – Wall Stud Design [AISI 2007b]. A proposal is also recommended to revise the wording in the North American Standard for Cold-Formed Steel Framing – Wall Stud Design [AISI 2007b] to include provisions for the design of jamb studs based on the results of this research.

The instanton solutions to the Yang-Mills equations have a vast range of practical applications in field theories including gravitation and electro-magnetism. Solutions to Maxwell's equations, for example, are abelian gauge instantons on Minkowski space. Since these discoveries, a generalised theory of instantons has been emerging for manifolds with special holonomy. Beginning with connections and curvature on complex vector bundles, this thesis provides some of the essential background for studying moduli spaces of instantons. Manifolds with exceptional holonomy are special types of seven and eight dimensional manifolds whose holonomy group is contained in G2 and Spin(7), respectively. Focusing on the G2 case, instantons on G2 manifolds are defined to be solutions to an analogue of the four dimensional anti-self-dual equations. These connections are known as Donaldson-Thomas connections and a couple of examples are noted.

Växjö university has together with Södra developed a new green-glued laminated beam, which to be used in a building system. To make a product of the beam it is desired to also develop a building system based on the beam. An important part of such a building system is the connections. The main aim of the thesis was to design a new beam-to-beam connection in for the new green-glued laminated boards. This thesis is about to develop and test a new connection for a beam-to-beam connection in the building system. The requirements set on the connection was that it should be used in an office building with a beam length of 6 m, the connection should be fast to assemble and invisible. The report thoroughly describes the conceptual design, the development and test of the connection. Five different types of connections were designed in the conceptual design phase. One of these connections fulfilled the requirements and was taken to the development and testing phase. Three versions of the connection were tested. The report describes how the green-glued laminated beams with the connections were tested in a testing machine until the failure occurs. The developed connection could fulfil the requirements set on the connection. One version of the connection was even stronger than the green-glued laminated beams.

Cold-formed steel structural members are used extensively in building construction, with a common application being wind load bearing steel studs. The studs frame into horizontal steel track members at the top and bottom of the wall assembly, with the stud-to-track connection typically being made with self-drilling screws or welds. The wall studs are designed to carry lateral loads only and must be checked for web crippling at the end reactions. While a design expression currently exists for the single stud-to-track connection, there is no similar design expression for multiple jamb stud members. An experimental investigation was carried out, consisting of 94 jamb stud assembly tests subjected to end-one-flange loading. The stud-to-track connections consisted of single C-section studs located at the end of a track simulating a door opening, and a built-up jamb made up of two studs simulating framing at either a window or door opening. The members were attached to the track with self-drilling screws. The research objective was to determine the failure modes and develop a design expression for these structural assemblies. The scope of the experimental investigation covered the following range of parameters: i) Stud and track depths of 92 mm and 152 mm; ii) Stud and track thickness (0.84 mm, 1.12 mm, 1.52 mm and 1.91 mm); iii) Configuration of jamb studs (back-to-back, toe-to-toe and single); iv) Location of jamb studs in the track (interior and end); v) Screw size (#8, #10 and #12); vi) Screw location (both flanges and single flange). Based on the findings of this investigation, design expressions are proposed to predict the capacity of this connection for two limit states: web crippling of the jamb stud; and, punch-through of the track. The web crippling design expression was taken from the North American Specification for the Design of Cold-Formed Steel Structural Members [AISI 2007a; CSA 2007] with new coefficients developed from the test data of the jamb stud-to-track assemblies. A new design expression is also proposed for the track punch-through failure mode, which differs from the approach currently used in the North American Standard for Cold-Formed Steel Framing – Wall Stud Design [AISI 2007b]. A proposal is also recommended to revise the wording in the North American Standard for Cold-Formed Steel Framing – Wall Stud Design [AISI 2007b] to include provisions for the design of jamb studs based on the results of this research.

The instanton solutions to the Yang-Mills equations have a vast range of practical applications in field theories including gravitation and electro-magnetism. Solutions to Maxwell's equations, for example, are abelian gauge instantons on Minkowski space. Since these discoveries, a generalised theory of instantons has been emerging for manifolds with special holonomy. Beginning with connections and curvature on complex vector bundles, this thesis provides some of the essential background for studying moduli spaces of instantons. Manifolds with exceptional holonomy are special types of seven and eight dimensional manifolds whose holonomy group is contained in G2 and Spin(7), respectively. Focusing on the G2 case, instantons on G2 manifolds are defined to be solutions to an analogue of the four dimensional anti-self-dual equations. These connections are known as Donaldson-Thomas connections and a couple of examples are noted.

A full-depth precast concrete deck system presents several safety, timeline, and cost benefits to the process of constructing a bridge, however the relevant professional codes do not provide dependable design models due to the limited amount of research conducted on the subject. One area lacking design direction is the development of a shear connection between the full-depth precast deck and a precast concrete girder via a pocket-haunch-connector system. Push-off tests are performed to investigate the effects of various pre- and post-installed shear connectors, haunch height, surface roughness, grouping effects, and grout composition as compared to cast-in-place specimens. The experimental results are presented along with a method for normalizing the variations of results by connection yield strength. This method is used to evaluate each connector type and connection parameter investigated. Ensuring sufficient shear reinforcement within the beam near the shear connector anchorage is found to be a vital aspect of holistic design. A simplified design procedure is outlined, the design connection forcedisplacement behavior is shown, and an example problem is solved. Recommendations for additions and modifications to current code and practice are prescribed.