Impact Tests for IRIS_2010 Benchmark Exercise

2012 ◽  
Vol 7 (5) ◽  
pp. 619-628 ◽  
Author(s):  
Ari Vepsä ◽  
◽  
Arja Saarenheimo ◽  
Francois Tarallo ◽  
Jean-Mathieu Rambach ◽  
...  

IRIS_2010 benchmark was an exercise in OECD/NEA/CSNI framework. This exercise concentrated on improving robustness assessment methodologies for structures impacted by missiles. This article describes experimental tests included in the exercise. These tests consisted of two tests for bending, three for punching and one for combined punching and bending behaviour of reinforced concrete walls under impact loading. The test for combined behaviour was carried out in Meppen, Germany in the 1980’s, while all the other tests were carried out by VTT Technical research centre of Finland during the spring of 2010. In the bending behaviour tests, 0.15 m thick simply supported square concrete walls with span width of 2 m were impacted with soft missiles weighing ∼50 kg and having velocity of ∼110 m/s at the impact moment. The impacts resulted maximum displacements of 29-32 mm at the centre of the wall with the permanent values being 8-9 mm. In the punching behaviour tests, similar walls but with thickness of 0.25 m were impacted with hard missiles weighing ∼47.5 kg and having velocity of ∼135 m/s at the impact moment. The impacts resulted perforation of the wall by the missile with residual velocity of the missile being 34-46 m/s. In addition, the walls suffered severe scabbing on the backside with the scabbed area being 1.00-1.12 m2.

Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6569
Author(s):  
Danilo Nicola Dongiovanni ◽  
Matteo D’Onorio

A Demo-Oriented early NEutron Source (DONES) facility for material irradiation with nuclear is currently being designed. DONES aims to produce neutrons with fusion-relevant spectrum and fluence by means of D–Li stripping reactions occurring between a deuteron beam impacting a stable liquid lithium flowing film implementing the target. Given the hazard constituted by the liquid lithium inventory and the potential risk of reactions with water, air, and concrete eventually resulting in fire events, the Target Test Cell (TTC) is filled with helium and the reinforced concrete walls forming the bio-shield are covered with steel liners. A loss of Li in TTC, due to a large break in the Quench Tank, is postulated, and consequences are deterministically studied. With the TTC liner being water-cooled, the impact of the liner temperature rise following a leakage event is evaluated. Two separate MELCOR code models have been defined for the liquid lithium loop and water-cooled loop and are numerically coupled. The amount of leaked inventory dependent on the implemented safety logic and impact on TTC containment is evaluated. The water pressurization pattern within the liner cooling loop is studied to highlight possible risks of lithium–water/concrete reactions.


Author(s):  
Darrell Lawver ◽  
Darren Tennant ◽  
John Mould ◽  
Howard Levine

Major components of storage facilities and nuclear power plants are designed using reinforced concrete walls. Accidental or intentional impact of these structures by aircraft is a concern. The potential for penetration of these facilities by the aircraft or its components and the subsequent damage to the contents and release of toxic substances is a major concern. This paper focuses on analyzing the impact of jet engines into heavily reinforced concrete walls. These engines are among the stiffest and most massive components of an aircraft and the most likely to seriously damage and penetrate the reinforced concrete. We model both the engine and the reinforced concrete deformations using failure models for reinforced concrete and metals. Unlike many projectile impact problems, the impacting engine cannot be considered to be rigid. A large amount of energy is consumed in the plastic deformation and fracture of the engine components. The reinforced concrete is modeled using hexahedral elements for the concrete and beam elements for the rebar reinforcement. An advanced three invariant viscoplastic softening cap constitutive model describes the ductile and brittle rate-dependent characteristics of concrete. The rebar is modeled using a rate dependent, strain hardening von Mises formulation with failure controlled by fracture energy dissipation. A similar constitutive model is employed for the shell elements used to represent the engine components. These failure models are included in the FLEX large deformation finite element code which uses an explicit, central difference solution procedure with subcycling to solve the equations of motion. Element erosion using different criteria for concrete and metals is used to remove severely distorted and failed elements. Procedures used to mitigate the deleterious and unrealistic effects of hourglass control and viscoplasticity in the softening and failure regimes are discussed. The results from the computations are compared with experimental data generated by impacting a TF-30 engine into a two foot thick concrete wall.


2018 ◽  
Vol 4 (9) ◽  
pp. 2060
Author(s):  
Mohammad Sadegh Barkhordari ◽  
Mohsen Tehranizadeh

According to the 2800 standard, the Iranian code of practice for seismic-resistant design of buildings, the base level refers to the level at which it is assumed that the horizontal movement of the ground is transmitted to the structure. In cases that there are reinforced concrete walls being run by an integrative structure in the underground perimeter, and the surrounding ground is dense and compressed, the base level is considered on the top of the basement wall. In tall structures, due to strong forces and moments at the foot of the structure, examining the location of base level and its movement becomes specially important. The aim of this study was to investigate the impact of changing the properties of the soil around the underground perimeter walls on the base level, taking into account the effects of soil-structure interaction systems. In this regard, the soil-structure system was investigated in two-dimensional models and the location of the base level was identified using shear and drift changes. The results indicated that taking into account the level of the upper stories is possible through performing appropriate walls integrated with the structure even without Compacting the soil around the structure.


2022 ◽  
Vol 12 (1) ◽  
pp. 518
Author(s):  
Bo Pu ◽  
Xiaoming Wang ◽  
Weibing Li ◽  
Jun Feng

Steel plate reinforced concrete (SC) walls can effectively resist projectile impact by preventing the rear concrete fragments flying away, thus attracting much attention in defence technology. This work numerically and analytically investigated the hard projectile perforation of steel plate reinforced concrete walls. Impact resistance theories, including cavity expansion analysis as well as the petaling theory of thin steel plates were used to describe the cratering, tunneling and plugging phases of SC walls perforation. Numerical modeling of SC walls perforation was performed to estimate projectile residual velocity and target destructive form, which were validated against the test results. An analytical model for SC wall perforation was established to describe the penetration resistance featuring five stages, i.e., cratering, tunneling and plugging, petaling with plugging and solely petaling. Analytical model predictions matched numerical results well with respect to projectile deceleration evolution as well as residual velocity. From a structural absorbed energy perspective, the effect of front concrete panel and rear steel plate thickness combinations was also studied and analyzed. Finally, equivalent concrete slab thickness was derived with respect to the ballistic limit of SC walls, which may be helpful in the design of a protective strategy.


Author(s):  
Prof. Subodh Dhoke

During earthquakes, a large number of buildings are destroyed due to the cause of lateral forces and increased load capacity in the structural element, and this is caused by winds, earthquakes and uneven settlement of cargo. The least damage and well-being a healthy level of construction is a necessary requirement for tall buildings. To reduce the impact of damage on all high structures, it may consist of basic insulation techniques and sliding walls, and so on. Buildings are used to increase design performance and limit damage to landslide walls. On tall buildings to prevent earthquake loads, reinforced concrete walls are used as supporting elements. Reinforced concrete structures are mainly implemented in engineering practice in different situations and different applications. Many researchers turn to the effectiveness of sliding walls with boundary conditions based on different types of reinforcement alignment. This document consists of modeling different models for the shear wall housing and the hood system.


2018 ◽  
Vol 34 (3) ◽  
pp. 1267-1288 ◽  
Author(s):  
Ana G. Haro ◽  
Mervyn Kowalsky ◽  
Y. H. Chai ◽  
Gregory W. Lucier

Large inelastic tensile strains and wide horizontal cracks primarily caused by in-plane loading, may lead to local out-of-plane deformations of the end regions of reinforced concrete (RC) walls within a buckled zone that comprises the plastic hinge length. Critical parameters that influence the onset of this failure mode have been studied through past experimental tests on RC prisms subjected to axial loading, which simulates the response of end regions of RC walls under in-plane demands. Missing from those studies is the effect of bidirectional loading protocols and the effect of the longitudinal reinforcement ratio on the hysteretic response. Therefore, 12 RC prisms with 3 longitudinal steel ratios representative of prototype boundary elements of typical special RC walls and piers walls were tested. The experimental results showed that the longitudinal steel content and the in-plane loading demands mainly govern the onset of out-of-plane buckling instability of planar RC walls.


2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Ari Wibowo ◽  
Indradi Wijatmiko ◽  
Christin R. Nainggolan

Precast concrete walls become increasingly utilized due to the rapid needs of inexpensive fabricated house especially as traditional construction cost continues to climb, and also, particularly at damaged area due to natural disasters when the requirement of a lot of fast-constructed and cost-efficient houses are paramount. However, the performance of precast walls under lateral load such as earthquake or strong wind is still not comprehensively understood due to various types of reinforcements and connections. Additionally, the massive and solid wall elements also enlarge the building total weight and hence increase the impact of earthquake significantly. Therefore, the precast polystyrene-reinforced concrete walls which offer light weight and easy installment became the focus of this investigation. The laboratory test on two reinforced concrete wall specimens using EPS (expanded polystyrene) panel and wire mesh reinforcement has been conducted. Quasi-static load in the form of displacement controlled cyclic tests were undertaken until reaching peak load. At each discrete loading step, lateral load-deflection behaviour, crack propagation, and collapse mechanism were measured which then were compared with theoretical analysis. The findings showed that precast polystyrene-reinforced concrete walls gave considerable seismic performance for the low-to-moderate seismic region reaching up to 1% drift at 20% drop of peak load. However, it might not be sufficient for high seismic regions, at which double-panel wall type can be more suitable.


2020 ◽  
Vol 7 (04) ◽  
Author(s):  
A B Priyanshu ◽  
M K Singh ◽  
Mukesh Kumar ◽  
Vipin Kumar ◽  
Sunil Malik ◽  
...  

An experiment was conducted at Horticultural Research Centre, SVP University of Agriculture and Technology, Meerut (UP) during Rabi season of 2018-19 to assess the impact of different INM doses on yield and quality parameters of garlic. A total of ten treatments consisting of combinations of inorganic fertilizers, organic fertilizers and bio-fertilizers like T1- (Control), T2RDF (100:50:50 kg NPK ha-1), T3-RDF + 20 kg sulphur + FYM 20 ton ha-1, T4- RDF + 20 kg sulphur + VC 4 ton ha-1, T5- 75% RDF + 40 kg sulphur + 5 ton FYM ha-1+ PSB 5 kg ha-1, T6-75% RDF + 40 kg sulphur + 2 ton VC + Azotobacter 5 kg ha-1, T7- 75% RDF + 40 kg sulphur + FYM 3 ton + VC 1 ton+ PSB 5 kg + Azotobacter 5kg ha-1, T8- 50% RDF + 40 kg sulphur + FYM 5 ton + VC2 ton + PSB 5 kg ha-1, T9- 50% RDF + 40 kg sulphur + FYM5 ton + VC 2 ton+ Azotobacter 5 kg ha-1and T10- 50% RDF + 40 kg sulphur + FYM 5 ton + VC2 ton + PSB 5 kg + Azotobacter 5 kg ha-1 were used in Randomized Block Design and replicated thrice. Out of these an application of T7 (75% RDF + 40 kg sulphur + FYM3 ton + VC 1 ton ha-1 + PSB 5 kg + Azotobacter 5 kg ha-1) was found to be significantly superior in term of yield and attributing parameters of garlic.


2021 ◽  
pp. 109963622110338
Author(s):  
Yury Solyaev ◽  
Arseniy Babaytsev ◽  
Anastasia Ustenko ◽  
Andrey Ripetskiy ◽  
Alexander Volkov

Mechanical performance of 3d-printed polyamide sandwich beams with different type of the lattice cores is investigated. Four variants of the beams are considered, which differ in the type of connections between the elements in the lattice structure of the core. We consider the pantographic-type lattices formed by the two families of inclined beams placed with small offset and connected by stiff joints (variant 1), by hinges (variant 2) and made without joints (variant 3). The fourth type of the core has the standard plane geometry formed by the intersected beams lying in the same plane (variant 4). Experimental tests were performed for the localized indentation loading according to the three-point bending scheme with small span-to-thickness ratio. From the experiments we found that the plane geometry of variant 4 has the highest rigidity and the highest load bearing capacity in the static tests. However, other three variants of the pantographic-type cores (1–3) demonstrate the better performance under the impact loading. The impact strength of such structures are in 3.5–5 times higher than those one of variant 4 with almost the same mass per unit length. This result is validated by using numerical simulations and explained by the decrease of the stress concentration and the stress state triaxiality and also by the delocalization effects that arise in the pantographic-type cores.


2021 ◽  
Vol 28 (1) ◽  
pp. 42-50
Author(s):  
Nicole M. Glenn ◽  
Lisa Allen Scott ◽  
Teree Hokanson ◽  
Karla Gustafson ◽  
Melissa A. Stoops ◽  
...  

Financial well-being describes when people feel able to meet their financial obligations, feel financially secure and are able to make choices that benefit their quality of life. Financial strain occurs when people are unable to pay their bills, feel stressed about money and experience negative impacts on their quality of life and health. In the face of the global economic repercussions of the COVID-19 pandemic, community-led approaches are required to address the setting-specific needs of residents and reduce the adverse impacts of widespread financial strain. To encourage evidence-informed best practices, a provincial health authority and community-engaged research centre collaborated to conduct a rapid review. We augmented the rapid review with an environmental scan and interviews. Our data focused on Western Canada and was collected prior to the pandemic (May–September 2019). We identified eight categories of community-led strategies to promote financial well-being: systems navigation and access; financial literacy and skills; emergency financial assistance; asset building; events and attractions; employment and educational support; transportation; and housing. We noted significant gaps in the evidence, including methodological limitations of the included studies (e.g. generalisability, small sample size), a lack of reporting on the mechanisms leading to the outcomes and evaluation of long-term impacts, sparse practice-based data on evaluation methods and outcomes, and limited intervention details in the published literature. Critically, few of the included interventions specifically targeted financial strain and/or well-being. We discuss the implications of these gaps in addition to possibilities and priorities for future research and practice. We also consider the results in relation to the COVID-19 pandemic and its economic consequences.


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