Design Proposal for Masonry Infill Walls Subject to Seismic Actions

Several factors influence the behaviour of masonry infilled frames, which have been the subject of previous research with moderate success. The new generation of European design standards imposes the need to prevent the brittle collapse of infills and makes the structural engineer accountable for this requirement, yet it fails to provide sufficient information for masonry infill design. The present study aimed to compare experimental results with the provisions of the standard for the computation of the demand and capacity of infilled frames. Three reinforced concrete buildings with different infill solutions were constructed at a 1:1.5 scale. The infill walls were tested until collapse, or severe damage, using the shake table of the National Laboratory for Civil Engineering, Portugal, and their response was measured using accelerometers attached to the walls. The European normative standard provides results close to the experimental ones as far as demand and capacity are concerned. Based on the experiments, two design proposals for infill walls are presented here, one for the definition of the natural frequency of the infills, and another for a reduction factor to account for the presence of openings in the out-of-plane capacity of infills.

Estimation Impact of Capital Development Projects on Adjacent Street and Road Network in Organization of Traffic by Means of Signal Controlled Intersections

The paper discusses problems of assessing the impact of mass attraction centers on the adjacent street and road network in the process of their functioning, expansion or conversion. The choice of criteria for assessing the organization of traffic flow, given in the Russian and foreign literature, has been substantiated, in particular, it is proposed to use v/c ratio for adjacent junction and corresponding level of traffic service (LOS). The main models for estimating capacity of signalized intersections are presented. The procedures of forming a mathematical model for estimating the load factor of signalized intersections is shown. The concepts of lane group capacity, total lost time per cycle, phase coefficients, saturation flow rate, and coefficients taking into account the decrease in the ideal saturation flow rate are explained. A mathematical model for estimating transport demand is presented, which allows to calculate the intensity of traffic flow to and from the center of mass attraction on the basis of the total traffic flow of correspondence, share of visitors in individual transport, average filling of individual transport, and coefficient of daily irregularity upon arrival and departure of visitors on an individual transport. An integrated mathematical model of loaf factor is proposed which includes parameters for estimating transport demand for centers of mass embarrassment and parameters that determine the signalized intersections capacity. The uniqueness of the integrated model is that it simultaneously involves parameters reflecting the demand and capacity of loading intersection. Recommendations are made on assessing the level of traffic service flows and the v/s ratio, based on the data of transport demand and capacity, adjacent to the centers of mass attraction of the road network. The presented method of estimating the LOS based on the capacity of the signalized intersections allows us to estimate the influence degree of mass attraction centers on the adjacent urban road network.

Effects of Shear Tabs and High-Strength Bolts in Seismic Performance of Steel Moment Connections

A shear tab and high-strength bolts are often used to connect a steel H-beam to a column. The design demand and capacity of these elements vary from one standard to the other. To investigate the effect, this study applied a finite element method (FEM) to develop models for two steel moment connections and validated the effectiveness by test data. The connections were characteristic of bolted-web-and-welded-flange details. The FEM models were then used to study the design of shear tabs and high-strength bolts in accordance with the U.S. and Japan standards and compared to the Taiwan practice. The result showed a small difference in the peak loads of the connections. However, the U.S. direct welded flange connection had flange buckling and strength degradation at a relatively smaller drift. The connection had a thinner shear tab and fewer high-strength bolts. The other two connections had very similar design results and loading responses. The increase in shear-tab thickness reduced the stress concentration and fracture potential of the connections. It is, therefore, recommended to design a shear tab with moment capacity greater than the beam web. This will reduce the stress concentration of the base metal surrounding the beam-flange groove welds, increasing the connection ductility.

Assessing readiness for lean thinking in healthcare settings: the case for Oman

PurposeHealthcare provision is costly, and patient expectations are increasing. Lean implemented within healthcare settings is one possible solution for dealing with this issue, with much of the current research in this respect mostly focused on developed countries. The research examines the applicability of lean in the healthcare sector of a developing country, specifically Oman.Design/methodology/approachInterviews were conducted with 32 individuals representing four public sector hospitals, along with two major hospital suppliers and the Ministry of Health. The readiness of lean thinking was assessed against seven criteria. Data were then analyzed thematically.FindingsThe authors found that Oman's healthcare sector is strong on leadership support, understanding value and customer groups, ability to undertake an end-to-end process view and engaging in the required training for lean. Interviewees showed awareness of the challenges, including aligning lean with the strategic agenda of healthcare settings, aligning measurement and reward systems to lean thinking and matching demand and capacity levels. The authors conclude that Oman's healthcare sector is ready for widespread application of lean, and if executed successfully, will generate strong strategic and operational outcomes.Originality/valueThis paper provides evidence of the applicability of lean in a very different context to the one that has been generally reported in the literature. The authors propose that lean thinking can be applied in countries and regions with similar cultural contexts such as the Middle East.