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Although having shown great promise for efficient water treatment, rational structural design and engineering of polycrystalline MOF membranes remain rarely investigated so far. In this study, we prepared well‐intergrown MOF‐801 membranes with tailorable structural deficiencies in the framework for application in dye rejection. Of particular note, we found that the addition of formic acid as modulator led to the formation of MOF‐801 membrane with higher missing‐linker number, which was beneficial for increasing water flux with little compromise in dye rejection rate. The MOF‐801 membrane prepared in this work exhibited excellent dye rejection performance (CR rejection rate of 99.50 % and water flux of 31.69 L m−2 h−1 bar−1) as well as excellent long‐term stability. [ABSTRACT FROM AUTHOR]

• Lack of proper inspection led to severe damage due to missing seismic reinforcement. • Problems arise from incomplete understanding of seismic design philosophy in the code. • Proper detailing in confinement reinforcement is crucial for the ductility of RC members. • High axial load levels on vertical members inhibit the required ductility in design. • Soft-story behavior is exacerbated under high axial load levels. Large magnitude February 6, 2023 earthquakes in Türkiye created a devastating effect on the building stock on a vast region. For earthquakes of this magnitude, severe damage and collapses are indispensable to the old building stock with deficiencies certified in previous earthquakes. But unexpectedly, the newly constructed buildings that were designed by recent version of Turkish Building Seismic Code (TBEC 2018) also experienced severe damage. After conducting site investigations on one of the recently constructed and severely damaged RC building, a detailed numerical study was performed to identify the reasons for the observed seismic damage. This study pinpoints the main cause of such damage due to lack of thorough building inspections during construction to ensure the implementation of the seismic reinforcement detailing specified in blueprints for providing required ductility, as revealed by field investigations. Additionally, it identifies potential issues stemming from a lack of full comprehension of the seismic design philosophy within the code. The existing design pushes the limits on the axial load level on slender column elements and fall short in capturing the soft story irregularity. Although there is a soft base story in the investigated building, using structural walls only in one direction with moderately confined boundary zones increased its vulnerability. This example shows that in Türkiye, where seismic activity is very high and quite lethal, seismic design codes should set stricter limits and measures, and building inspection system must be strictly enforced. [ABSTRACT FROM AUTHOR]

Cross-linguistically, personal pronouns are noted as being deficient in relation to some morphosyntactic and phonological properties. Some striking asymmetries have been identified between strong and weak personal pronouns in relation to modification, coordination/conjunction, whether they have a semantic referent, and can encode focus. This study explores the personal pronominal system of Dagbani along Cardinaletti and Starke’s (1994) typology and observed asymmetries. Using insights from published literature on Dagbani pronouns as well as my understanding as a native speaker, I argue that, unlike personal pronouns in Romance/Germanic languages, Dagbani personal pronouns can be modified by quantifiers, can be coordinated, and can occur in conjunction constructions, as well as encode topic and focus as salient semantic discourse properties. Furthermore, the pre/post verbal distinctions among nonemphatic pronominal forms in Dagbani still hold, even as these occur in coordinated and modified constructions, due to structural constraints imposed on them by coordinating conjuctions and quantifiers.

A moderate earthquake with a magnitude Mw of 6.8 occurred in the Sivrice district of Elazığ Province in Eastern Turkey on January 24th, 2020. The mainshock and long-term aftershocks gave rise to considerable structural damage and affected the local society. Remarkable property loss took place due to building damages and collapses. The reasons for the losses and structural damages are investigated by the post-earthquake field observations. The importance of earthquake-resistant design principles and applications outlined in the current and former seismic codes is verified through the field reconnaissance. To this end, the seismic damage observed after the Elazığ-Sivrice Earthquake in the non-structural and structural elements of the RC structures is reported. The conflict between the code requirements and actual conditions of construction practices is also established. The seismic vulnerability of substandard RC buildings is quantified in association with the structural weaknesses and deficiencies observed in the earthquake-affected region. The reasons behind the unexpectedly extensive damage at the local and global level under such a moderate earthquake are based on the vulnerability of substandard buildings resulting from structural deficiencies, poor material qualities, and lack of control mechanism during construction. [ABSTRACT FROM AUTHOR]

Cross-linguistically, personal pronouns are noted as being deficient in relation to some morphosyntactic and phonological properties. Some striking asymmetries have been identified between strong and weak personal pronouns in relation to modification, coordination/conjunction, whether they have a semantic referent, and can encode focus. This study explores the personal pronominal system of Dagbani along Cardinaletti and Starke's (1994) typology and observed asymmetries. Using insights from published literature on Dagbani pronouns as well as my understanding as a native speaker, I argue that, unlike personal pronouns in Romance/Germanic languages, Dagbani personal pronouns can be modified by quantifiers, can be coordinated, and can occur in conjunction constructions, as well as encode topic and focus as salient semantic discourse properties. Furthermore, the pre/post verbal distinctions among nonemphatic pronominal forms in Dagbani still hold, even as these occur in coordinated and modified constructions, due to structural constraints imposed on them by coordinating conjunctions and quantifiers. [ABSTRACT FROM AUTHOR]

Buried concrete rectangular liquid storage tanks are categorized as key elements in lifeline network for fluid storage, especially potable water. A large number of them were built in Iran before 1980, without taking any seismic considerations, which their performance after an earthquake is a matter of concern. Thus, understanding the seismic behavior of these tanks in terms of water tightness, serviceability conditions, damage levels, and downtime days in case of an earthquake is crucial from the perspective of post-earthquake performance. Furthermore, research into the behavior of such rectangular-shaped tanks is complicated mainly because of the soil-tank-water interaction and the presence of expansion joints. Hence in this study, a series of small-scale experimental tests, using 1 g shaking table, were provided to investigate the effect of amplitude and frequency of input excitation on model responses with regard to the water level, the buried depth, and the density of surrounding soil. The results presented the pattern of soil cracks and showed that empty tanks had greater displacements than full ones. In addition, better performance was observed in the tanks embedded deeper and in denser soil. The damping ratios in full-water tanks were obtained more than in empty ones. Finally, within the framework of this study, the experimental results were compared with ACI 350-6 code; the results of hydrodynamic pressure showed acceptable agreement between two methods, except at the resonance frequency. However, some discrepancy was observed in results related to the phase of the dynamic soil force. [ABSTRACT FROM AUTHOR]

Long-term bridge performance data available in the NBI database was used to identify statistical trends between several qualitative and quantitative performance criteria that correlate to higher or lower prevalences of structural deficiency in US bridges. An internet-based resource which compiles and inventories all bridge inspection data for all bridges, nationwide into a single, interfaced LTBP database “Bridge Portal”. The approach is to extract data on bridge material, climate, span length, average daily traffic volume, and ownership for structurally deficient bridges and to compare and correlate the sampled data from the total bridge population nationwide. A method is designed to process this data through several normalization and adjustment filters that correct for sample size and account for structural age, which is the final parameter. The advantage of this approach is that it separates deficiency from basic structural and material assumptions and includes other relevant factors that might not otherwise have been considered or previously explored in such detail. Analysis results and implications of these results to the present and future conditions of the United States’ bridge infrastructure network are presented. [ABSTRACT FROM AUTHOR]

The present study is focused on the experimental investigation and nonlinear finite element simulations of shear deficient and glass fibre reinforced plastic (GFRP) strengthened reinforced concrete beams. Three levels of shear deficiency are considered in the design. Two layers of GFRP fabric are used for strengthening in the shear zone. The behavior of control, shear deficient and GFRP strengthened beams under two-point monotonic loading is studied. Detailed 3D non-linear finite element analyses with perfect bonding as well as with cohesive zone modelling are carried out to simulate the behavior of shear deficient beams. The responses, in terms of load-deflection behavior, failure loads and crack patterns, obtained from numerical simulations are validated with that of the experimental investigations. The validated numerical models are then used for studying the efficacy and effectiveness of various strengthening schemes using epoxy impregnated GFRP fabric where the number of layers, orientation and distribution of fibres are considered as parameters. Based on the parametric studies, the schemes which provide optimum improvement in performance for strengthening of the shear deficient beams are identified. For all three classes of deficient beams, greatest improvement in strength is attained for 45° orientation in single ply, 45°–90° orientation in double ply and 90°–45°–90° orientation in triple ply strengthening schemes. In all GFRP strengthened beams, mode of failure changed from shear to flexural failure and showed great improvement in the ductile behavior. [ABSTRACT FROM AUTHOR]

1992 Erzincan depremi ile başlayan ve günümüze kadar geçen 14 yıllık süre içerisinde yaşamış olduğumuz orta ve büyük ölçekli depremlerde, daha yüksek bina önem katsayıları ile tasarlanmalarına rağmen kamu yapılarının da diğer yapılar gibi hasar gördüğü ve yıkıldığı görülmüştür. Sağlık, eğitim, yönetim ve güvenlik amacıyla kullanılan binaların özellikle tasarım depreminde hasar görmemesi ve deprem sonrasında da hemen kullanılabilir durumda olması gereklidir. Bu çalışmada; son yıllarda deprem dayanımları incelenen 105 kamu yapısında taşıyıcı sistem kusurları incelenmiştir. Karşılaşılan kusurlar örneklenmiştir. Diğer yapılarda pek gözlenmeyen bazı değişik problemlere ait örnekler verilmiştir.

A majority of Iranian residential buildings have RC frame structures which are in-filled with masonry walls. Structural deficiencies of in-filled RC frame structures are focused in this probabilistic seismic assessment. The seismic design of 3, 5 and 8 story RC frame structures are carried out according to the current Iranian seismic code and then 3 dimensional analytical models analyzed based on Incremental Dynamic Analysis (IDA) in OpenSEES. The demand statistics in terms of maximum inter-story drift ratio are obtained for 20 sets of ground motion records and the capacity is determined according to the HAZUS-MH limit states and finally the corresponding fragility curves are developed. The results represent the effect of the story numbers, structural deficiency and masonry infill walls in the seismic vulnerability of this subclass of structures. [ABSTRACT FROM AUTHOR]

• Main reasons for the collapse of a steel structure of a factory were investigated. • Buckling analyses were carried out to prove the field observations. • Progressive collapse mechanism of the structure was determined. • Lateral torsional buckling behavior is vital importance of the steel connections' stability. • Analytical results agreed well with the field investigations. The structural design process has many vital roles in preventing the collapse of structures and should be conducted according to national obligatory standards. However; structural failures or even catastrophic collapses based on improper design, underestimated design loads, unexpected extreme loads, and improper erection are reported worldwide on large-span structures. A steel structure of the factory partially collapsed under expected snow loads in the western part of Turkey was investigated in this study. The possible reasons for the collapse of the system were examined by visual inspections and analytical results. The load-carrying capacities of the main girders and purlins were determined using the buckling analyses of the structural member. The nonlinear geometric analysis of the entire steel structural system was defined to evaluate the vertical load-carrying capacity of the main girder. The progressive collapse mechanism of the system was determined. The obtained results indicate that the snow load is not the main reason for the collapse and mistakes in the project design, constructional defects and inadequate capacity of structural elements are the primary reasons behind the collapse. [ABSTRACT FROM AUTHOR]

The excavation of a large-sized foundation pit for one skyscraper in Shanghai required installation of a 100-m diameter unpropped circular diaphragm wall at the pit center first, followed by installation of a multipropped rectangular diaphragm wall at the periphery. Due to the limited paper length, this study just focuses on the structural behaviors of the inner circular wall and those of the outer rectangular wall will be presented in a companion paper. The circular diaphragm wall exhibited apparent spatial arching effects during excavation and only slight differences were observed in its maximum lateral movements along the circumference. Like braced struts, waler beams mainly carried the load due to soil removal in the proximity. In contrast, the circular diaphragm wall carried the hoop stresses due to soil removal throughout the excavation. The vertical bending stresses in diaphragm wall panels were symmetric about their neutral axes. Although the adopted remedial measure effectively mitigated their potential adverse effects on wall deformations, structural deficiencies (e.g., diaphragm wall panels encountered the existing long driven piles at several locations) resulted in some detrimental effects (e.g., tension stress development in concrete and uneven stress distributions in retaining structures). Throughout the construction, the stress development patterns in concrete corresponded well with those in reinforcing rebars, which indicated that the retaining structures were not overstressed. The comparisons between the design analysis results and the field measurements show that the adopted beam-on-elastic-foundation method can make relatively reasonable estimation on excavation-induced deflections of the unpropped circular retaining wall. [ABSTRACT FROM AUTHOR]