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Nepal is one of the regions in the world that is most vulnerable to earthquakes as it lies at the boundary of the actively converging Indo-Australian plate and Eurasian Plate. Most of the infrastructure in Nepal has been constructed by individuals based on their own needs and budget without consulting engineers, and several studies have shown that...
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... Short Column Effect The effect of short columns is often overlooked in the design and construction of the buildings. The short column effect can either result from partial height infill walls, the addition of an extra connection beam to support a staircase, or from sloping ground as shown in Figure 18. When there is a short column in a structure it attracts more lateral shear forces and needs to be designed accordingly. Some of the observed effects of short columns are shown in Figure 19. 4.1.3 Design and Detailing Problems Another major problem with current design and construction practice in Nepal is detailing of reinforcement in reinforced concrete structures. The quantity and quality of the reinforcement used in these building is often inadequate in terms of achieving the required capacity. Strength hierarchies are often not considered, and appropriate detailing is not employed, resulting in non-ductile behaviour. Some of the common detailing problems are insufficiently large spacing of ties in columns and beams, inadequate anchorage of reinforcement, improper bending of hooks, insufficient reinforcement in the connection regions, not enough cover, and improper splicing of reinforcement. Figure 20 shows some of the detailing ...
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... In the M 7.8 Nepal earthquake in 2015, the shaking intensity (Peak Ground Acceleration: PGA < 0.2g) in Kathmandu was only moderate, but the strong motion recordings of ~ 0.5g spectral acceleration at ~ 5s period (e.g. Pokharel and Goldsworthy 2015) seem to indicate that practically any modern high-rise building (say > 40 stories) would have been vulnerable to collapse in these long period motions. ...
A New Paradigm (data driven and not like the currently model driven) is needed for Reliable Seismic Hazard Assessment RSHA. Neo-Deterministic Seismic Hazard Assessment (NDSHA) integrates earthquake geology, earthquake science, and particularly earthquake physics to finally achieve a New (and needed) Paradigm for Reliable Seismic Hazard Assessment RSHA.Although observations from many recent destructive earthquakes have all confirmed the validity of NDSHA’s approach and application to earthquake hazard forecasting-nonetheless damaging earthquakes still cannot yet be predicted with a precision requirement consistent with issuing a red alert and evacuation order to protect civil populations. However, intermediate-term (time scale) and middle-range (space scale) predictions of main shocks above a pre-assigned threshold may be properly used for the implementation of low-key preventive safety actions, as recommended by UNESCO in 1997. Furthermore, a proper integration of both seismological and geodetic information has been shown to also reliably contribute to a reduction of the geographic extent of alarms and it therefore defines a New Paradigm for TimeDependent Hazard Scenarios: Intermediate-Term (time scale) and Narrow-Range (space scale) Earthquake Prediction.
... In the M 7.8 Nepal earthquake in 2015, the shaking intensity (Peak Ground Acceleration: PGA < 0.2g) in Kathmandu was only moderate, but the strong motion recordings of ~ 0.5g spectral acceleration at ~ 5s period (e.g. Pokharel and Goldsworthy 2015) seem to indicate that practically any modern high-rise building (say > 40 stories) would have been vulnerable to collapse in these long period motions. ...
A New Paradigm (data driven and not like the currently model driven) is needed for Reliable Seismic Hazard Assessment RSHA. Neo-Deterministic Seismic Hazard Assessment (NDSHA) integrates earthquake geology, earthquake science, and particularly earthquake physics to finally achieve a New (and needed) Paradigm for Reliable Seismic Hazard Assessment RSHA.Although observations from many recent destructive earthquakes have all confirmed the validity of NDSHA’s approach and application to earthquake hazard forecasting-nonetheless damaging earthquakes still cannot yet be predicted with a precision requirement consistent with issuing a red alert and evacuation order to protect civil populations. However, intermediate-term (time scale) and middle-range (space scale) predictions of main shocks above a pre-assigned threshold may be properly used for the implementation of low-key preventive safety actions, as recommended by UNESCO in 1997. Furthermore, a proper integration of both seismological and geodetic information has been shown to also reliably contribute to a reduction of the geographic extent of alarms and it therefore defines a New Paradigm for TimeDependent Hazard Scenarios: Intermediate-Term (time scale) and Narrow-Range (space scale) Earthquake Prediction.
... The effect of short columns is often overlooked in the design and construction of the buildings. The short column effect can either result from partial height infill walls, the addition of an extra connection beam to support a staircase, or from sloping ground [5]. Reinforced concrete (RC) members in concrete buildings are typically subjected to a combination of bending, shear and axial. ...
This research is an attempt to understand and model the performance of short columns under different ground levels and storey number. This behaviour includes varying axial forced, shear forces, and bending moments under gravity loads. All the results have been taken for the columns at the ground level when the phenomenon of the short column has appeared. To study the performance of short columns under different ground levels and the number of stories, the 3D finite element by sap2000, and multiple linear regression analysis have been used in this study. The results show that the axial force for all types of short columns (internal, edge, corner) increases as the number of stories in the building increases at the same ground level. The effect of changing the number of floors with the same value of ground level is not significant in shear and moment for all types of columns except for the one-story and two-storey buildings. For more illustration, the moment and shear for a building composed of one story is very high compared to the two-storey building where the value becomes significantly low; then become higher again with a 3-storey building and with more stories.
... Similarly, Bertero and Brokken [14] concluded that the building stiffness increases from 366% to 944% depending upon the variation in the layout of the infill walls. Despite large positive contribution evidences; negative influence instigated by the irregular distribution of infill walls contribute to the structural failures (i.e., soft-storey, short-column mechanisms), observed from several postearthquake field survey performed by Rodrigues et al. [15] and also in the post-earthquake field survey conducted in Nepal after 25th April, 2015, Gorkha earthquake [16][17][18][19]. In addition, Varum [11] also revealed that the infill walls along with the surrounding frames behaves monolithically in resisting the lateral forces but for low to medium magnitude earthquakes. ...
... The maximum increases can be obtained for fully infilled and minimum for soft-storey building case. The increase in stiffness for three storeys building ranges (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) and (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16) times in X and Y directions, respectively. In addition, the increase in stiffness four storeys varies from (6-21) and (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17) times in X and Y directions, respectively. ...
... The maximum increases can be obtained for fully infilled and minimum for soft-storey building case. The increase in stiffness for three storeys building ranges (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) and (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16) times in X and Y directions, respectively. In addition, the increase in stiffness four storeys varies from (6-21) and (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17) times in X and Y directions, respectively. ...
The present study investigates the vulnerability assessment of the prototype revised MRT buildings initially designed and detailed for three storeys bare frame building; later modified through variable number of storeys (three, four and five) and different arrangement of infill walls (bare frame, softstorey, irregular infilled and fully infilled). The application of infill walls increases the fundamental frequencies, stiffness and maximum strength capacity, but reduces the deformation capability than the bare frame building. The vulnerability was also reduced through infill walls, where the probability of exceeding partial-collapse and collapse damage reduced by 80% and 50%, respectively. Furthermore, the increased in storeys (three to five) also increases the failure probability, such that partial-collapse and collapse for fully infilled increases by almost 55% and 80%, respectively. All obtained results and discussions concluded that the structural sections and details assigned for MRT building is not sufficient if considered as bare frame and soft-storey. And increase in number of storeys causes building highly vulnerable although the infill walls were considered.
... T. Pokharel et. al. (7), presented a summary of the reconnaissance survey of a major earthquake of magnitude 7.8 (on 25th of April, 2015) with epicentre in Gorkha District in Nepal, followed by a series of aftershocks including magnitude of 7.3 on the 12th of May 2015.Rajat Srivastava et. al. (8), presented paper to improve the efficiency of real time earthquake risk mitigation methods and its capability of protecting structures, infrastructures and people, to investigate a multistorey RCC building (G +9 Story) for Zone 2, to look at seismic conduct of multistorey RCC building for specific shaking power regarding reactions, to contemplate the impacts of various Seismic zones on execution of multi-story working as far as seismic, to know the connection between various techniques for seismic investigation and their seismic reactions, to accomplish functional learning on basic investigation, seismic examination, outlining and specifying of auxiliary segments utilizing standards of Earthquake Resistant Design.A.C. Ragavan et. ...
Humanitarian crises can exacerbate vulnerabilities if attention is not paid to the specific needs of populations. As this study finds, youth voice has rarely been included in humanitarian discourse, whether through policy development and/or program implementation. However, youth-led activism evidenced in response to the 2016 Ebola and 2020 COVID-19 pandemics challenge this disregard of youth voice. This case study seeks to bridge this gap by investigating data from the youth-organized Earthquake Response Youth Partnership (ERYP), a six-month coalition between four youth-run NGOs and one UN agency in the aftermath of the 2015 Nepal earthquake(s). The methodology is informed through social media content and analyses the interactions of youth activists through this familiar medium. After analysing social media content before, during and after the short-term partnership, I elaborate how their choices inspired continued youth civic participation and social engagement. After conducting a thematic analysis, this study finds that youth led and engage through: : first response, needs assessment, evaluation and education. As the analysis informs, youth-led organizations were quick to mobilize, utilizing existing networks and partnerships. This positioning enabled them to assess youth needs and evaluate youth-centric programming. Thus, they gained influenced over community processes, like education and preparedness. Together, this active approach to initiate, mobilise and connect through virtual platforms not only amplified youth voice, but aligned individual growth on a path towards national development. The key contribution of this study is to emphasize the importance of locally led youth activism through social media during times of crisis. In doing so, the study argues for youth voice to be included in development discourse and humanitarian programming.
“You never change things by fighting the existing reality. To change something, build a new model that makes the existing model obsolete.” — Buckminster Fuller.
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The Neo-Deterministic Seismic Hazard Assessment (NDSHA) method, proposed some twenty years ago, is found to reliably and realistically simulate the wide suite of earthquake ground motions that may impact civil populations as well as their heritage buildings.
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The scenario-based NDSHA modeling technique is developed from comprehensive physical knowledge of: (i) the seismic source process; (ii) the propagation of earthquake waves; and (iii) their combined interactions with site conditions.
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Thus, NDSHA effectively accounts for the tensor nature of earthquake ground motions.
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Observations from recent destructive earthquakes in Italy: (i) Mw 5.9 Emilia 2012; (ii) Central Italy Mw 6.3 L'Aquila 2009; and 2016–2017 Seismic Crisis - Mw 6.1 Amatrice; Mw 5.9 Visso; Mw 6.5 Norcia; Mw 5.7 L'Aquila; and (iii) Mw 7.8 Nepal 2015 - have all confirmed the validity of NDSHA's approach and application.
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Although damaging earthquakes cannot yet be predicted with ultimate precision, intermediate-term (several months) and middle-range (few 100 s km scale) predictions of main shocks above a pre-assigned threshold (based on seismicity “alarms” generated by interpretive algorithms like CN and M8) may be properly used for the implementation of low-key preventive safety actions.
