Post-liquefaction reconsolidation of sand.

Loosely packed sand that is saturated with water can liquefy during an earthquake, potentially causing significant damage. Once the shaking is over, the excess pore water pressures that developed during the earthquake gradually dissipate, while the surface of the soil settles, in a process called post-liquefaction reconsolidation. When examining reconsolidation, the soil is typically divided in liquefied and solidified parts, which are modelled separately. The aim of this paper is to show that this fragmentation is not necessary. By assuming that the hydraulic conductivity and the one-dimensional stiffness of liquefied sand have real, positive values, the equation of consolidation can be numerically solved throughout a reconsolidating layer. Predictions made in this manner show good agreement with geotechnical centrifuge experiments. It is shown that the variation of one-dimensional stiffness with effective stress and void ratio is the most crucial parameter in accurately capturing reconsolidation.This is the author accepted manuscript. The final version is available from Royal Society Publishing via https://doi.org10.1098/rspa.2015.074

Use of viscous pore fluids in dynamic centrifuge modelling

The scaling laws that arise from dynamic centrifuge modelling contain an inconsistency regarding the scaling of time between dynamic and diffusion events. This problem can be resolved by reducing the permeability of the soil, with the help of high-viscosity pore fluids. Hydroxypropyl methylcellulose is a water-soluble cellulose ether that is widely used to create such fluids. In this paper, the effects that concentration, temperature, ageing and shearing rate have on the viscosity of hydroxypropyl methylcellulose solutions are examined and equations that quantify them are presented. This information is meant to act as a guideline for the preparation of high-viscosity pore fluids for dynamic centrifuge tests. This is the accepted manuscript currently embargoed pending publication. Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Earthquake environmental effects and ESI 2007 of the 6th February 2023 Kahramanmaraş earthquakes along the East Anatolian Fault Zone (Türkiye)

The February 6, 2023 Kahramanmaraş earthquake doublet resulted in a range of devasting impacts on the built and natural environments. Here the macroseimic intensity of the event is assessed using the Environmental Seismic Intensity Scale (ESI 2007), which considers a range of primary and secondary earthquake environmental effects (EEEs) resulting from the causative earthquakes. These features were documented as part of the hybrid Earthquake Engineering Field Investigation Team (EEFIT) mission and by numerous other studies in the aftermath of the earthquakes. The primary fault ruptures along segments of the East Anatolian Fault Zone exceeded 350 km along the Pazarcık segment (the first fault to rupture) with a maximum displacement (Dmax) of ∼8 m, and 150 km with a Dmax ∼7–8 m along the Çardak-Sürgü Fault, which subsequently ruptured later the same day in an event termed the Elbistan or Ekinözü earthquake. In addition, a range of other secondary effects such as landslides and rockfalls, liquefaction and lateral spreading, changes to springs, tsunami and widespread damage were reported over an area \u3e35,000 km2. These data indicate epicentral intensities of XI and X for the Pazarcık and Elbistan earthquakes, respectively, consistent with the intensity inferred from measured offsets along these faults. Whereas site intensities based upon various secondary effects range from VIII – XI. Given the close association in time and space of the two main shock events it is difficult to attribute the wider off-fault secondary features to either event, especially where the faults converge in the north, but there is good correlation with: a) the mapped fault traces and many documented EEEs occur with 10–15 km of the rupture; and b) measured peak ground acceleration (PGA), where ESI 2007 intensities of \u3e X correspond to regions experiencing \u3e0.2 g PGA, and there are a few EEEs where PGA did not exceed 0.05 g. However, both maximum reported moment magnitude intensity (MMI) and Did You Feel It (DYFI) reports are 1–3° lower than the ESI 2007 values derived here, possibly resulting from bias towards urban areas. These data not only highlight the utility of using environmental effects in earthquake intensity studies but also suggest that the Kahramanmaraş earthquakes are unprecedented within the historical record of the region

The real challenges for climate and weather modelling on its way to sustained exascale performance: a case study using ICON (v2.6.6)

The weather and climate model ICON (ICOsahedral Nonhydrostatic) is being used in high-resolution climate simulations, in order to resolve small-scale physical processes. The envisaged performance for this task is 1 simulated year per day for a coupled atmosphere–ocean setup at global 1.2 km resolution. The necessary computing power for such simulations can only be found on exascale supercomputing systems. The main question we try to answer in this article is where to find sustained exascale performance, i.e. which hardware (processor type) is best suited for the weather and climate model ICON, and consequently how this performance can be exploited by the model, i.e. what changes are required in ICON's software design so as to utilize exascale platforms efficiently. To this end, we present an overview of the available hardware technologies and a quantitative analysis of the key performance indicators of the ICON model on several architectures. It becomes clear that parallelization based on the decomposition of the spatial domain has reached the scaling limits, leading us to conclude that the performance of a single node is crucial to achieve both better performance and better energy efficiency. Furthermore, based on the computational intensity of the examined kernels of the model it is shown that architectures with higher memory throughput are better suited than those with high computational peak performance. From a software engineering perspective, a redesign of ICON from a monolithic to a modular approach is required to address the complexity caused by hardware heterogeneity and new programming models to make ICON suitable for running on such machines.</p

Hybrid EEFIT mission to february 2023 Kahramanmaraş earthquake sequence

The southwestern part of Türkiye was hit on 6 February 2023 by an Mw 7.8 (epicentre:Pazarcık) and then an Mw 7.5 earthquake (epicentre: Elbistan). The event was followed by tensof thousands of aftershocks including the Mw 6.3 event on 20 February (epicentre: Uzunbağ).This paper reports on the preliminary findings of the mission organised by the UK’s EarthquakeEngineering Field Investigation Team (EEFIT) to the Kahramanmaraş Earthquake sequence ofFebruary 2023. This mission followed a hybrid model, combining field and remote investigationtechniques, to investigate the characteristics of the earthquake sequence, its impact on buildingsand infrastructure, as well as the efficacy of relief, response and recovery operations. The keymessages include that the building stock is hard to categorise which brings along difficulties withdamage assessment, that the recovery and reconstruction require multi-sectoral engagement ofkey stakeholders, and that the auditing and quality control mechanisms within the constructionindustry need revisiting in the way forward for better disaster resilience in Türkiye

The Türki̇ye earthquake sequence of February 2023: A longitudinal study report by EEFIT

On 6 February 2023 at 4:17 am local time, a large area in southeastern Türkiye and northern Syria was hit by an Mw 7.8 earthquake, which was followed by an Mw 7.5 earthquake at 1:24 pm local time, causing the loss of more than 50,000 lives, some 100,000 injuries and significant damage to buildings and infrastructure, estimated to be in the range of 84.1 billion USD for Türkiye alone. The largest earthquake in Türkiye since the deadly 1939 Erzincan earthquake with however much larger losses, the sequence immediately attracted the attention of the global post-disaster reconnaissance/engineering communities. This included the Earthquake Engineering Field Investigation Team (EEFIT), who, within one week of the event, gathered a team with 30 people from academia and industry in the UK (19), Türkiye (5), New Zealand (1), Hungary (1), Bulgaria (1), Greece (1) and USA (1) with two support members from the UK and the Netherlands, to study the events and their impacts, and also to develop suggestions to reduce the existing vulnerabilities in the future. The team was organised in the form of 6 working groups as shown below, which were (1) strong ground motions and seismotectonics, (2) geotechnics, (3) structures, (4) infrastructure, (5) remote sensing and (6) relief response and recovery

2023 Türki̇ye deprem sekansi deprem mühendi̇sli̇ği̇ saha çalişmalari eki̇bi̇ (EEFIT) Misyonu: Türkçe geni̇şleti̇lmi̇ş özet

Türkiye'nin güneydoğusunda ve kuzey Suriye'de geniş bir alan, 6 Şubat 2023 tarihinde yerel saatle sabaha karşı 04:17'de gerçekleşen 7.8 büyüklüğünde yıkıcı bir depremle sarsıldı, aynı gün içerisinde 13:24’te meydana gelen 7.5 büyüklüğündeki deprem ile yıkımın boyutu ve etki alanı büyük ölçüde arttı. Bu depremler, yalnızca Türkiye'de 84.1 milyar $’ı (≈2.5 trilyon ₺) aşan ekonomik kayba, bina ve altyapı stokunda ciddi hasara, 100,000'den fazla yaralı ve 50,000'den fazla can kaybına neden oldu

A search for new physics in central exclusive production using the missing mass technique with the CMS detector and the CMS-TOTEM precision proton spectrometer

A generic search is presented for the associated production of a Z boson or a photon with an additional unspecified massive particle X, pp → pp + Z/γ + X, in proton-tagged events from proton–proton collisions at √s = 13 TeV, recorded in 2017 with the CMS detector and the CMS-TOTEM precision proton spectrometer. The missing mass spectrum is analysed in the 600–1600 GeV range and a fit is performed to search for possible deviations from the background expectation. No significant excess in data with respect to the background predictions has been observed. odelindependent upper limits on the visible production cross section of pp → pp + Z/γ + X are set