scholarly journals Energy Absorption Capacity Of Rat-Trap Bond Masonry Under Base Excitation

2021 ◽  
Vol 23 (11) ◽  
pp. 454-461
Author(s):  
Eshetu Mathewos Juta ◽  
Keyword(s):  
Absorption Capacity ◽  
Brick Masonry ◽  
Seismic Loads ◽  
Masonry Building ◽  
Lateral Loads ◽  
Energy Absorption Capacity ◽  
Code Of Practice ◽  
Building Models ◽  
Bond System ◽  
Heavy Damage

Brick masonry does not exhibit much capacity to resist lateral loads and hence the masonry suffers heavy damage during earthquakes, which impart lateral loads to structures. In the Bhuj earthquake of Jan 26, 2001, that occurred in majority of masonry structures failed because they were built with un-reinforced brick masonry. The EBC code of practice for brick masonry, suggests the use of lintel band and roof band that introduce a rigid box-type behavior which will help the structure to improve its performance against seismic loads. But there are no Codal provisions for use of Rat-Trap bond masonry which has been found to possess good seismic resistance characteristics. Rat-Trap bond system consists of an array of headers and stretchers with bricks laid vertically on the edge to form a cavity within a set of two headers and two stretchers. In this investigation, an attempt has been made to study the behavior of un-reinforced Rat-Trap bond masonry of two categories viz., (i) with roof slab, and (ii) without roof slab. Shock-table tests on one-third scale masonry building models ( with and without roof slabs ) were carried out to study the behavior. The peak accelerations were recorded for each shock. The scaled bricks were obtained by cutting locally available bricks using special tools. The size of the masonry models was 2m x 1m x 1m. The amount of energy imparted during each shock was measured before total collapse both for Rat-Trap bond masonry models with and without roof slabs. The results of the tests revealed that the roof weight plays an important role in the design of Rat-Trap masonry systems subject to seismic loads.

scholarly journals PVC Plastic Tube with Concrete Infill Strengthened with FRP: A State-of-the-art Review

2020 ◽  
Vol 9 (4) ◽  
pp. 196-204
Author(s):  
Nwzad Abduljabar Abdulla
Keyword(s):  
Research Work ◽  
Concrete Columns ◽  
Absorption Capacity ◽  
Fiber Reinforced Polymers ◽  
Structural Members ◽  
Lateral Loads ◽  
Energy Absorption Capacity ◽  
Plastic Tube ◽  
Reinforced Polymers ◽  
Compression Members

The strength and energy absorption capacity of concrete compression members are a significant concern when considering the structural performance under axial and lateral loads. A lot of methods and different techniques have been proposed in the past to improve the behavior of concrete columns under the applied loads. One such technique is the concrete filled-plastic tube (CFPT) strengthened externally with fiber-reinforced polymers (FRP). Such a system can improve the durability of the structural members. A review of the research work on the durability of the new system under axial and flexural loads is presented. Moreover, a comparison and a brief discussion of the reported results are displayed.  

ALUMINUM ALLOY 201.0

Alloy Digest ◽  
1995 ◽  
Vol 44 (7) ◽  
Keyword(s):  
Aluminum Alloy ◽  
High Temperature ◽  
Physical Properties ◽  
High Strength ◽  
Heat Treating ◽  
Absorption Capacity ◽  
Casting Alloy ◽  
Permanent Mold ◽  
Energy Absorption Capacity ◽  
Temperature Performance

Abstract ALUMINUM ALLOY 201.0 is a structural casting alloy available as sand, permanent mold and investment castings. It is used in structural casting members, applications requiring high tensile and yield strengths with moderate elongation, and where high strength and energy-absorption capacity are needed. This datasheet provides information on composition, physical properties, and elasticity as well as creep and fatigue. It also includes information on high temperature performance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: AL-336. Producer or source: Various aluminum companies.

scholarly journals Electrical Performance of Polymer-Insulated Rail Brackets of DC Transit Subjected to Lightning Induced Overvoltage

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1684
Author(s):  
Farah Asyikin Abd Rahman ◽  
Mohd Zainal Abidin Ab Kadir ◽  
Ungku Anisa Ungku Amirulddin ◽  
Miszaina Osman
Keyword(s):  
Performance Comparison ◽  
Absorption Capacity ◽  
Electrical Performance ◽  
Sensitivity Analyses ◽  
Lightning Strike ◽  
Rail Transit ◽  
Energy Absorption Capacity ◽  
Urban Transit ◽  
Residual Voltage ◽  
Reinforced Plastic

The fourth rail transit is an interesting topic to be shared and accessed by the community within that area of expertise. Several ongoing works are currently being conducted especially in the aspects of system technical performances including the rail bracket component and the sensitivity analyses on the various rail designs. Furthermore, the lightning surge study on railway electrification is significant due to the fact that only a handful of publications are available in this regard, especially on the fourth rail transit. For this reason, this paper presents a study on the electrical performance of a fourth rail Direct Current (DC) urban transit affected by an indirect lightning strike. The indirect lightning strike was modelled by means of the Rusck model and the sum of two Heidler functions. The simulations were carried out using the EMTP-RV software which included the performance comparison of polymer-insulated rail brackets, namely the Cast Epoxy (CE), the Cycloaliphatic Epoxy A (CEA), and the Glass Reinforced Plastic (GRP) together with the station arresters when subjected by 30 kA (5/80 µs) and 90 kA (9/200 µs) lightning currents. The results obtained demonstrated that the GRP material has been able to slightly lower its induced overvoltage as compared to other materials, especially for the case of 90 kA (9/200 µs), and thus serves better coordination with the station arresters. This improvement has also reflected on the recorded residual voltage and energy absorption capacity of the arrester, respectively.

Numerical and experimental investigation for enhancing the energy absorption capacity of the novel three-dimensional printed sandwich structures

2021 ◽  
pp. 146442072199749
Author(s):  
H Geramizadeh ◽  
S Dariushi ◽  
S Jedari Salami
Keyword(s):  
Energy Absorption ◽  
Sandwich Structures ◽  
Three Dimensional ◽  
Absorption Capacity ◽  
The Novel ◽  
Energy Absorption Capacity ◽  
Fused Deposition ◽  
Honeycomb Sandwich ◽  
Out Of Plane ◽  
Vertical Walls

The current study focuses on designing the optimal three-dimensional printed sandwich structures. The main goal is to improve the energy absorption capacity of the out-of-plane honeycomb sandwich beam. The novel Beta VI and Alpha VI were designed in order to achieve this aim. In the Beta VI, the connecting curves (splines) were used instead of the four diagonal walls, while the two vertical walls remained unchanged. The Alpha VI is a step forward on the Beta VI, which was promoted by filleting all angles among the vertical walls, created arcs, and face sheets. The two offered sandwich structures have not hitherto been provided in the literature. All models were designed and simulated by the CATIA and ABAQUS, respectively. The three-dimensional printer fabricated the samples by fused deposition modeling technique. The material properties were determined under tensile, compression, and three-point bending tests. The results are carried out by two methods based on experimental tests and finite element analyses that confirmed each other. The achievements provide novel insights into the determination of the adequate number of unit cells and demonstrate the energy absorption capacity of the Beta VI and Alpha VI are 23.7% and 53.9%, respectively, higher than the out-of-plane honeycomb sandwich structures.

scholarly journals Dynamic crushing behavior of closed-cell aluminum foams based on different space-filling unit cells

2021 ◽  
Vol 21 (3) ◽  
Author(s):  
S. Talebi ◽  
R. Hedayati ◽  
M. Sadighi
Keyword(s):  
Surface Area ◽  
Dynamic Behavior ◽  
Energy Absorption ◽  
Peak Stress ◽  
Absorption Capacity ◽  
Unit Cell ◽  
Lattice Structures ◽  
Energy Absorption Capacity ◽  
Closed Cell ◽  
Unit Cells

AbstractClosed-cell metal foams are cellular solids that show unique properties such as high strength to weight ratio, high energy absorption capacity, and low thermal conductivity. Due to being computation and cost effective, modeling the behavior of closed-cell foams using regular unit cells has attracted a lot of attention in this regard. Recent developments in additive manufacturing techniques which have made the production of rationally designed porous structures feasible has also contributed to recent increasing interest in studying the mechanical behavior of regular lattice structures. In this study, five different topologies namely Kelvin, Weaire–Phelan, rhombicuboctahedron, octahedral, and truncated cube are considered for constructing lattice structures. The effects of foam density and impact velocity on the stress–strain curves, first peak stress, and energy absorption capacity are investigated. The results showed that unit cell topology has a very significant effect on the stiffness, first peak stress, failure mode, and energy absorption capacity. Among all the unit cell types, the Kelvin unit cell demonstrated the most similar behavior to experimental test results. The Weaire–Phelan unit cell, while showing promising results in low and medium densities, demonstrated unstable behavior at high impact velocity. The lattice structures with high fractions of vertical walls (truncated cube and rhombicuboctahedron) showed higher stiffness and first peak stress values as compared to lattice structures with high ratio of oblique walls (Weaire–Phelan and Kelvin). However, as for the energy absorption capacity, other factors were important. The lattice structures with high cell wall surface area had higher energy absorption capacities as compared to lattice structures with low surface area. The results of this study are not only beneficial in determining the proper unit cell type in numerical modeling of dynamic behavior of closed-cell foams, but they are also advantageous in studying the dynamic behavior of additively manufactured lattice structures with different topologies.

scholarly journals Static Mechanical Properties of Expanded Polypropylene Crushable Foam

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 249
Author(s):  
Przemysław Rumianek ◽  
Tomasz Dobosz ◽  
Radosław Nowak ◽  
Piotr Dziewit ◽  
Andrzej Aromiński
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Strain Rate ◽  
Energy Absorption ◽  
Experimental Tests ◽  
Absorption Capacity ◽  
Strain Rates ◽  
Foam Density ◽  
Energy Absorption Capacity ◽  
Closed Cell

Closed-cell expanded polypropylene (EPP) foam is commonly used in car bumpers for the purpose of absorbing energy impacts. Characterization of the foam’s mechanical properties at varying strain rates is essential for selecting the proper material used as a protective structure in dynamic loading application. The aim of the study was to investigate the influence of loading strain rate, material density, and microstructure on compressive strength and energy absorption capacity for closed-cell polymeric foams. We performed quasi-static compressive strength tests with strain rates in the range of 0.2 to 25 mm/s, using a hydraulically controlled material testing system (MTS) for different foam densities in the range 20 g/dm3 to 220 g/dm3. The above tests were carried out as numerical simulation using ABAQUS software. The verification of the properties was carried out on the basis of experimental tests and simulations performed using the finite element method. The method of modelling the structure of the tested sample has an impact on the stress values. Experimental tests were performed for various loads and at various initial temperatures of the tested sample. We found that increasing both the strain rate of loading and foam density raised the compressive strength and energy absorption capacity. Increasing the ambient and tested sample temperature caused a decrease in compressive strength and energy absorption capacity. For the same foam density, differences in foam microstructures were causing differences in strength and energy absorption capacity when testing at the same loading strain rate. To sum up, tuning the microstructure of foams could be used to acquire desired global materials properties. Precise material description extends the possibility of using EPP foams in various applications.

Mechanical Response of Porous Copper Manufactured by Lost Carbonate Sintering Process

2007 ◽  
Vol 539-543 ◽  
pp. 1863-1867 ◽  
Author(s):  
X.F. Tao ◽  
Li Ping Zhang ◽  
Y.Y. Zhao
Keyword(s):  
Particle Size ◽  
Flexural Strength ◽  
Relative Density ◽  
Mechanical Response ◽  
Compaction Pressure ◽  
Absorption Capacity ◽  
Energy Absorption Capacity ◽  
Three Point Bending ◽  
Porous Copper ◽  
The Impact

This paper investigated the mechanical response of porous copper manufactured by LCS under three-point bending and Charpy impact conditions. The effects of the compaction pressure and K2CO3 particle size used in producing the porous copper samples and the relative density of the samples were studied. The apparent modulus, flexural strength and energy absorption capacity in three-point bending tests increased exponentially with increasing relative density. The impact strength was not markedly sensitive to relative density and had values within 7 – 9 kJ/m2 for the relative densities in the range 0.17 – 0.31. The amount of energy absorbed by a porous copper sample in the impact test was much higher than that absorbed in the three-point bending test, impling that loading strain rate had a significant effect on the deformation mechanisms. Increasing compaction pressure and increasing K2CO3 particle size resulted in significant increases in the flexural strength and the bending energy absorption capacity, both owing to the reduced sintering defects.

In Situ Lateral Load Testing of a Two-Story Solid Clay Brick Masonry Building

2018 ◽  
Vol 32 (5) ◽  
pp. 04018058 ◽  
Author(s):  
Alper Aldemir ◽  
Baris Binici ◽  
Erdem Canbay ◽  
Ahmet Yakut
Keyword(s):  
Lateral Load ◽  
Brick Masonry ◽  
Masonry Building ◽  
Load Testing ◽  
Clay Brick

scholarly journals Cementitious Composites Reinforced with Polypropylene, Nylon and Polyacrylonitile Fibres

2012 ◽  
Vol 730-732 ◽  
pp. 271-276
Author(s):  
H.R. Pakravan ◽  
M. Jamshidi ◽  
M. Latifi ◽  
F. Pacheco-Torgal
Keyword(s):  
Absorption Capacity ◽  
Cement Matrix ◽  
Cementitious Composites ◽  
Scanning Electron Micrographs ◽  
Energy Absorption Capacity ◽  
Cement Ratio ◽  
Pull Out ◽  
Water To Cement Ratio ◽  
Before And After ◽  
Scanning Electron

This paper compares the adhesion strength between three polymeric fibres (polypropylene (PP), nylon66 (N66) and polyacrylonitrile (PAN)) embedded in a cement paste. The specimens were prepared at a water to cement ratio (w/c) of 0.5 and tested after 7, 14 and 28 curing days. It was found that although the adhesion between the polymeric fibres to the cement matrix is an important factor, the energy absorption capacity or energy dissipation ability of the fibres, plays a more important role in the improvement of the cementitious composites fracture toughness. Scanning electron micrographs were used to characterize the fibres surface before and after the Pull-out tests.

Sign in / Sign up

Export Citation Format

Share Document