Load-Path and Stiffness Degradation of Floor Diaphragms in Reinforced Concrete Buildings Subjected to Lateral Loading - Part I, Experimental Observations.

An experimental investigation into the degradation of load-paths in damaged diaphragms was conducted to provide answers to the New Zealand structural engineering community following concerns that strut-and-tie load-paths could not cross wide cracks that develop around the floor perimeter during earthquake loading demands. A full-scale super-assembly concrete moment frame specimen with a hollow-core flooring system installed was subjected to realistic drift deformations to induce damage in the floor, followed by in-plane shear deformation demands to assess the ability of the diaphragm to transfer load between frames at different floor damage levels. It was found that compression struts could form across much wider cracks in floors than previously anticipated. This was due to contact compressive stresses forming via loose aggregate that lodged within rugged sinusoidal wide floor cracks. Additionally, it was found that diaphragm compression struts can only transfer to the primary lateral load resisting frame through beam plastic hinges acting in minor axis shear following gaps opening between the floor and columns at moderate drift demands. Smooth floor to column interfaces did not provide the same residual rubble aggregate binding compressive load path observed in cracks within the floor. The primary driver of diaphragm shear stiffness degradation was found to be torsional softening of the perimeter beams of the floor. This was caused by simultaneous bi-directional demands applied to longitudinal beam bars and a phenomenon known as the bowstring effect applying large torsional demands through the beam-floor continuity reinforcement. The diaphragm strength and rate of shear stiffness degradation was found to be highly reliant on earthquake directionality. A set of generalised equations was developed to describe the rate of diaphragm shear stiffness degradation with respect to magnitude and directionality of drift demands. Part I of II in this journal series details the full-scale super-assembly experiment conducted on a floor diaphragm at different damage states and the observed behaviour during testing

Ultrahigh ionic exclusion through carbon nanomembranes

The collective “single‐file” motion of water molecules through natural and artificial nanoconduits inspires the development of high‐performance membranes for water separation. However, a material that contains a large number of pores combining rapid water flow with superior ion rejection is still highly desirable. Here, a 1.2 nm thick carbon nanomembrane (CNM) made from cross‐linking of terphenylthiol (TPT) self‐assembled monolayers is reported to possess these properties. Utilizing their extremely high pore density of 1 sub‐nm channel nm−2, TPT CNMs let water molecules rapidly pass, while the translocation of ions, including protons, is efficiently hindered. Their membrane resistance reaches ≈104 Ω cm2 in 1 m Cl− solutions, comparable to lipid bilayers of a cell membrane. Consequently, a single CNM channel yields an ≈108 higher resistance than pores in lipid membrane channels and carbon nanotubes. The ultrahigh ionic exclusion by CNMs is likely dominated by a steric hindrance mechanism, coupled with electrostatic repulsion and entrance effects. The operation of TPT CNM membrane composites in forward osmosis is also demonstrated. These observations highlight the potential of utilizing CNMs for water purification and opens up a simple avenue to creating 2D membranes through molecular self‐assembly for highly selective and fast separations

Comparison of different stomatal conductance algorithms for ozone flux modelling

A multiplicative and a semi-mechanistic, BWB-type [Ball, J.T., Woodrow, I.E., Berry, J.A., 1987. A model predicting stomatalconductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggens, J. (Ed.), Progress in Photosynthesis Research, vol. IV. Martinus Nijhoff, Dordrecht, pp. 221–224.] algorithm for calculating stomatalconductance (gs) at the leaf level have been parameterised for two crop and two tree species to test their use in regional scale ozone deposition modelling. The algorithms were tested against measured, site-specific data for durum wheat, grapevine, beech and birch of different European provenances. A direct comparison of both algorithms showed a similar performance in predicting hourly means and daily time-courses of gs, whereas the multiplicative algorithm outperformed the BWB-type algorithm in modelling seasonal time-courses due to the inclusion of a phenology function. The re-parameterisation of the algorithms for local conditions in order to validate ozone deposition modelling on a European scale reveals the higher input requirements of the BWB-type algorithm as compared to the multiplicative algorithm because of the need of the former to model net photosynthesis (An

Validity and Reliability of Turkish Version of Olerud-Molander Ankle Score in Patients With Malleolar Fracture.

The present study was planned to translate and culturally adapt the Olerud-Molander Ankle Score (OMAS) and assess the validity and reliability of the Turkish translation of the OMAS in patients with surgically treated malleolar fracture. The OMAS was adapted for use in Turkish by first translating it and then back-translating it in accordance with published guidelines. The final Turkish version of the OMAS was administered to 91 patients participating in the present study. The OMAS questionnaire was repeated 7 days later to assess test-retest reliability. Spearman's rank correlation analysis was used for each question's score and the total score, and the intraclass correlation coefficient was calculated for test-retest reliability. The internal consistency of the OMAS-TR was assessed using Cronbach's α. Concurrent validity was evaluated by comparing the OMAS with the Foot and Ankle Outcome Score and global self-rating function (GSRF). The GSRF has 5 options: very good, good, fair, poor, and very poor. These are assessed using a 5-point Likert scale. Before validity analysis, the GSRF score was reduced to 3 groups. In the test-retest reliability assessment, the OMAS showed high correlation (r = 0.882). The intraclass correlation coefficient was 0.942. Cronbach's α was 0.762 and 0.731 at days 1 and 7 (adequate internal consistency). The correlation coefficients versus the 5 subscales of the Foot and Ankle Outcome Score ranged from r = 0.753 to r = 0.809 (p = .000) and versus the GSRF was r = -0.794 (p = .000). According to results of the present study, the Turkish version of the OMAS demonstrated adequate test-retest reliability, excellent internal consistency, and evidence of validity for Turkish-speaking patients treated surgically for ankle fracture

Two years results of supervised physiotherapy and home exercise programmes in patients with arthroscopic assisted mini-open rotator cuff repair

The aim was the presentation of two years results of supervised physiotherapy and home exercise programmes in patients with arthroscopic assisted mini-open rotator cuff repair. Demographic parameters, and data for applied exercise programme after arthroscopic assisted mini-open rotator cuff repair, and preoperative, postoperative 6.th month, and postoperative 2 years data for pain level (VAS, Visual Analog Scale), Range of motion (ROM), quality of life (Short Form-36, SF-36), functional evaluation of upper extremity (Disabilities of arm, shoulder and hand- Turkish, DASH-T) were recorded retrospectively from records of patients. Significant improvements were detected for pain, ROM, DASH-T, SF-36 for both of supervised physiotherapy group (N=17, mean age=59,82±5,44 years), and home exercise group (N=17, mean age=59,52±11,42 years) at postoperative 6.th month and postoperative second year compared to preoperative evaluation. While significant improvements were detected for activity pain, extension and external rotation ROM in favor of home exercise programme group, there were no differences for other evaluation parameters between groups at second year evaluation. Results of both of supervised physiotherapy and home exercise programme after arthroscopic assisted mini-open rotator cuff repair were improved and the postoperative improvements continued after two years from the operation in both of two exercise groups