scholarly journals Research on the Mechanism of the Influence of Earthquake-Induced Landslides on the Stress and Deformation Characteristics of Tunnel

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Yufang Zhang ◽  
Hongyu Liu ◽  
Jian Li ◽  
Qidi Huang ◽  
Xianjie Ma ◽  
...  
Keyword(s):  
Shear Failure ◽  
Concrete Strength ◽  
Weak Links ◽  
Tunnel Structure ◽  
Railway Tunnel ◽  
Supporting Structure ◽  
Limit Value ◽  
Seismic Shear ◽  
The Right ◽  
The Impact

The landslide at the entrance of a railway tunnel in the southwestern region is relatively large, especially due to earthquakes and other factors, which are prone to severe disasters and threaten the safety of the tunnel. Through the long-term monitoring test and numerical calculation analysis on-site, the mechanism of the influence of the earthquake-induced landslide on the characteristics of the tunnel’s force and deformation is studied. The research results show that the earthquake caused the landslide thrust to increase. Because of the existence of the supporting structure, the landslide thrust was consumed, and the remaining part resulted in the compression failure of the tunnel. During the seismic monitoring period, the stress loss of the antislide pile anchor cable was 3.73% and the stress of the second lining of the tunnel increased by 25%. Under the condition of extreme seismic, shear failure occurred at the vault, bottom, and waist of the right-line tunnel, and the tensile strength of the right-line tunnel reached 93.8% of the limit value. For the weak links of the tunnel structure, dense reinforcement planting and strengthening of concrete strength should be adopted to enhance the safety of the tunnel structure. While designing the supporting structure, the rock-socketing depth of the antislide piles and the number of antislide piles should be considered a priority. The impact of the antislide pile spacing is relatively small.

scholarly journals Research on the Interaction Mechanism between Landslide and Tunnel Engineering

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Yufang Zhang ◽  
Jian Li ◽  
Hongyu Liu ◽  
Wei Li ◽  
Jiaming Li ◽  
...  
Keyword(s):  
Large Scale ◽  
Shear Failure ◽  
Concrete Strength ◽  
Interaction Mechanism ◽  
Tunnel Structure ◽  
Tunnel Engineering ◽  
Railway Tunnel ◽  
Maximum Deformation ◽  
Limit Value ◽  
The Impact

The landslide at the entrance of a railway tunnel is large scale, and serious diseases are prone to appear under natural disasters, which threaten the safety of the tunnel. According to its characteristics, on-site long-term monitoring experiments and numerical analysis were carried out, and the mechanism of interaction between landslide and tunnel engineering was analyzed. The results show that under the impact of rainfall and earthquake, the original internal stress balance in the landslide body is disturbed, leading to the increase in landslide thrust and damage of the tunnel lining. Simultaneously, the excavation of the tunnel can slack the surrounding rock to increase the landslide thrust and make the landslide be finally formed; this landslide conversely acts on the tunnel, resulting in deformation and destruction of the tunnel. During the monitoring, under the influence of rainfall and earthquake, the stress of the secondary lining was continuously increased by 25%. Tunnel construction caused a maximum deformation of 30 mm in the antislide pile at a distance of 2.12 m, and the slope and the tunnel were also affected. Under extreme conditions such as rainfall and earthquake, shear failure occurred at the vault, bottom, and waist of the right-line tunnel located at the junction of soil and rock; at this time, the tensile strength of the tunnel reached 93.8% of the limit value of concrete, which seriously affected the safety of the tunnel. As for the weakened tunnel structure, measures such as dense planting and strengthening of concrete strength should be adopted to enhance the safety of the tunnel structure.

scholarly journals Effect of CFRP Shear Strengthening on the Flexural Performance of the RC Specimen under Unequal Impact Loading

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yanhui Liu ◽  
Khalil Al-Bukhaiti ◽  
Hussein Abas ◽  
Zhao Shichun
Keyword(s):  
Reinforced Concrete ◽  
Impact Loading ◽  
Shear Failure ◽  
Impact Load ◽  
Concrete Strength ◽  
Impact Behavior ◽  
Parameter Study ◽  
Dynamic Amplification Factor ◽  
Flexural Performance ◽  
The Impact

Strengthening with externally bonded CFRP reinforcement is widely used in structural reinforcement and attractive to stakeholders and engineers because of ease and speed of construction, corrosion resistance, lightweight, high strength, and versatility stiffness which can be oriented according to the need. Numerous research studies were carried out to explore RC beams’ flexural and shear performance when subjected to dynamic impact loading. The results were auspicious in using such a technique of strengthening. Regular square section reinforced concrete frame members strengthened by CFRP material is taken as the research object. However, little attention to the impact behavior of CFRP-shear-strengthened square reinforced concrete (RC) specimens has been paid. The dynamic response of CFRP to reinforced concrete members under unequal cross-impact is discussed. This paper investigates the effectiveness of CFRP strengthening on the square RC specimen in preventing shear failure and evaluation of the flexural performance of the strengthened specimen under the impact load. The drop hammer impact test is firstly conducted on RC specimens with and without CFRP strengthening. The results show that using CFRP to strengthen the RC specimen in shear is very effective at preventing shear failure and leading the specimen’s response to flexural domination. This result is also the motivation for developing a numerical model supported by experimental tests to study the flexural performance of strengthened RC specimens. It is found that the strengthened specimen is prone to exhibit pure bending deformation under the impact load in terms of dynamic amplification factor (DAF) for section moment. Then, an extensive parameter study is carried out to evaluate further the influence of impact velocity, reinforcement ratio, and concrete strength on the flexural performance of the strengthened specimen and CFRP layers. Such a holistic study may provide preliminary research regarding the use of CFRP to strengthen RC specimens in shear under impact loads and will enhance the current state of knowledge in this area; also, the optimal value of the CFRP reinforcement layer was proposed.

Behaviour of flexural plastic hinges under high seismic shear with consideration of concrete strength

2009 ◽  
Vol 36 (11) ◽  
pp. 1711-1721 ◽  
Author(s):  
Abdelsamie Elmenshawi ◽  
Tom Brown ◽  
Robert Loov
Keyword(s):  
Shear Strength ◽  
Shear Failure ◽  
Concrete Strength ◽  
Shear Behaviour ◽  
Experimental Program ◽  
Concrete Element ◽  
Shear Deformations ◽  
Plastic Hinges ◽  
Cyclic Shear ◽  
Seismic Shear

A successful seismic design for a reinforced concrete element is one that can postpone the shear failure until the required ductility and deformation capacity are obtained. After flexural yielding, shear deformations are the main causes for strength and stiffness degradation. An experimental program was carried out to explore the shear behaviour of flexural plastic hinges of elements constructed with different concrete strengths (30–175 MPa) tested under load reversals. The specimen represented a beam–column assembly and was designed to have the inelastic deformation at the beam end only. The research investigated the effect of shear deformations on the hysteretic behaviour and stiffness deterioration, cyclic shear demands, shear resisting mechanisms, and the effect of concrete strength on the hinge shear strength. It was found that the effect of concrete strength on beam shear strength under cyclic loading differs from that under unidirectional loading.

Emotional Reactivity to Visual Content as Revealed by ERP Component Clustering

2015 ◽  
Vol 29 (4) ◽  
pp. 135-146 ◽  
Author(s):  
Miroslaw Wyczesany ◽  
Szczepan J. Grzybowski ◽  
Jan Kaiser
Keyword(s):  
Emotional Reactivity ◽  
Brain Activity ◽  
Affective State ◽  
Occipital Lobe ◽  
Stimulus Onset ◽  
Emotional States ◽  
Neural Basis ◽  
Temporoparietal Junction ◽  
The Right ◽  
The Impact

Abstract. In the study, the neural basis of emotional reactivity was investigated. Reactivity was operationalized as the impact of emotional pictures on the self-reported ongoing affective state. It was used to divide the subjects into high- and low-responders groups. Independent sources of brain activity were identified, localized with the DIPFIT method, and clustered across subjects to analyse the visual evoked potentials to affective pictures. Four of the identified clusters revealed effects of reactivity. The earliest two started about 120 ms from the stimulus onset and were located in the occipital lobe and the right temporoparietal junction. Another two with a latency of 200 ms were found in the orbitofrontal and the right dorsolateral cortices. Additionally, differences in pre-stimulus alpha level over the visual cortex were observed between the groups. The attentional modulation of perceptual processes is proposed as an early source of emotional reactivity, which forms an automatic mechanism of affective control. The role of top-down processes in affective appraisal and, finally, the experience of ongoing emotional states is also discussed.

The Impact of Internal Work Environment on the Retention of Healthcare Providers at Turaif General Hospital

2019 ◽  
Vol 10 (12) ◽  
pp. 1183-1199
Author(s):  
Mohammed Alrouili ◽  
Keyword(s):  
Work Environment ◽  
General Hospital ◽  
Professional Growth ◽  
Healthcare Providers ◽  
Entire Study ◽  
Internal Work ◽  
Research Findings ◽  
Study Population ◽  
The Right ◽  
The Impact

This study attempted to identify the impact of internal work environment on the retention of healthcare providers at Turaif General Hospital in the Kingdom of Saudi Arabia. In particular, the study aimed to identify the dimensions of work circumstances, compensation, and relationship with colleagues, professional growth, and the level of healthcare providers’ retention. In order to achieve the study goals, the researcher used the descriptive analytical approach. The researcher used the questionnaire as the study tool. The study population comprised all the healthcare providers at Turaif General Hospital. Questionnaires were distributed to the entire study sample that consisted of 220 individuals. The number of questionnaires valid for study was 183 questionnaires. The research findings were as follows: the participants’ estimate of the work circumstances dimension was high (3.64), the participants’ estimate of the compensation dimension was moderate (3.32), the participants’ estimate of the relationship with colleagues dimension was high (3.62), the participants’ estimate of the professional growth dimension was weak (2.39), and the participants’ estimate of healthcare providers’ retention level was intermediate (2.75). Accordingly, the researcher’s major recommendations are: the need to create the right atmosphere for personnel in hospitals, the interest of the hospital to provide the appropriate conditions for the staff in terms of the physical and moral aspects for building the work adjustment in the staff, and conducting training courses and educational lectures for personnel in hospitals on how to cope with the work pressures.

The Right to Housing: Challenges Associated with the ‘Waiting List System’ Ekurhuleni Metropolitan Municipality V Various Occupiers, Eden Park Extension 5 2014 3 SA 23 (SCA)

2017 ◽  
Vol 30 (1) ◽  
pp. 112-121
Author(s):  
Shamier Ebrahim
Keyword(s):  
Supreme Court ◽  
Waiting Lists ◽  
The State ◽  
Waiting List ◽  
Allocation Process ◽  
The Supreme Court ◽  
The Right ◽  
The Impact ◽  
Court Of Appeal

The right to adequate housing is a constitutional imperative which is contained in section 26 of the Constitution. The state is tasked with the progressive realisation of this right. The allocation of housing has been plagued with challenges which impact negatively on the allocation process. This note analyses Ekurhuleni Metropolitan Municipality v Various Occupiers, Eden Park Extension 51 which dealt with a situation where one of the main reasons provided by the Supreme Court of Appeal for refusing the eviction order was because the appellants subjected the unlawful occupiers to defective waiting lists and failed to engage with the community regarding the compilation of the lists and the criteria used to identify beneficiaries. This case brings to the fore the importance of a coherent (reasonable) waiting list in eviction proceedings. This note further analyses the impact of the waiting list system in eviction proceedings and makes recommendations regarding what would constitute a coherent (reasonable) waiting list for the purpose of section 26(2) of the Constitution.

Global tolerance and its impact on peace

2019 ◽  
pp. 247-284
Author(s):  
م.د.فاتن محمد رزاق
Keyword(s):  
Islamic Law ◽  
Mutual Recognition ◽  
International Community ◽  
World Peace ◽  
Clash Of Civilizations ◽  
Democracy And Education ◽  
Moral Necessity ◽  
International Identity ◽  
The Right ◽  
The Impact

The concept of tolerance is gaining its importance in the midst of an international society suffering from violence, wars and internal and international crises. It is practiced by extremist and extremist forces and movements acting in the name of religion to exclude the different Muslim and non-Muslim people according to the unethical practices and methodologies of Islamic law and reality. , Cultural, civilization .. that distinguish our world today. The society today is suffering from the ideas of the intellectual and aesthetic views of the different ideologically, ethnically, culturally and religiously in the world of the South. This is what the end-of-history thesis of Fukuyama and the clash of civilizations represented to Huntington. Therefore, it is necessary to confront these extremist and extremist ideas and behaviors. Peace, security and freedom in the international community of justice and equality, needs to be addressed intellectual, cultural, moral and political before they are legal, these treatments are based on dialogue and cooperation and trust and respect and mutual recognition and tolerance so we find the importance of tolerance to The international community is concerned about the need for mechanisms that confront terrorism and violence with an ideology based on respect for the right of diversity, diversity and pluralism. Accordingly, tolerance is a political, cultural and moral necessity based on international legal foundations represented by the United Nations. Through its conferences, declarations and international resolutions issued by it and its specialized agencies, culminating in the Universal Declaration of Tolerance and the International Day of International Peace, and the political foundations represented by democracy and global citizenship that respects all identities and seeks to respect the rights of other identities under the umbrella of international identity Nsanhuahdh respects everyone, a society with a humanitarian goal of a global civil and Ahdlaaaraf borders and the identity of certain Qomahdolh, cultural and educational foundations through plans and programs with educational encourage a spirit of tolerance and world peace. The study was divided into three topics: the first dealt with the concept of tolerance and world peace, and the second topic dealt with the impact of international law and citizenship. In the promotion of world peace "as one of the elements of global tolerance. The last topic included" the role of democracy and education education "in the promotion of world peace and concluded the study by conclusion.

The Right to Information in India Implementation and Impact

2015 ◽  
Vol 2 (1) ◽  
pp. 17
Author(s):  
_______ Naveen ◽  
_____ Priti
Keyword(s):  
Public Life ◽  
Public Authorities ◽  
The Public ◽  
Know How ◽  
The People ◽  
The Government ◽  
Right To Information ◽  
The Right ◽  
The Impact

The Right to Information Act 2005 was passed by the UPA (United Progressive Alliance) Government with a sense of pride. It flaunted the Act as a milestone in India’s democratic journey. It is five years since the RTI was passed; the performance on the implementation frontis far from perfect. Consequently, the impact on the attitude, mindset and behaviour patterns of the public authorities and the people is not as it was expected to be. Most of the people are still not aware of their newly acquired power. Among those who are aware, a major chunk either does not know how to wield it or lacks the guts and gumption to invoke the RTI. A little more stimulation by the Government, NGOs and other enlightened and empowered citizens can augment the benefits of this Act manifold. RTI will help not only in mitigating corruption in public life but also in alleviating poverty- the two monstrous maladies of India.

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