Load Deflection and Ultimate Strength Properties of Sandwich Lightweight Foamed Concrete Panels

The interaction that exists between two wythes of concrete, inner and outer, goes a long way to establish the structural behavior of the whole components and particularly, lightweight foamed concrete sandwich panel. Precast concrete sandwich panel (PCSP) has become a household name since it has been utilized in the construction of structural shell in some building types. This research investigated the load deflection of six different lightweight foamed concrete panels. The six panels were produced using a foamed concrete mix of the same density and the mechanical properties of the mix were tested. Each panel consists of two withes (facings) made of lightweight foamed concrete and polystyrene was used as the core and the insulation layer. Mild steel wire mesh of 6mm sizes was used as reinforcement in three of the panels while 9mm diameter high yield steel was used in the remaining three panels. The reinforcement in both facing was tied together using shear and bend to an angle of 450.End crushing of the panels was avoided using concrete capping. An axial load test was conducted, the load deflection, mode of failure and crack patterns of the panels was observed. The result also revealed that panels with concrete capping deflect along with their Wythe in the same directions and small deflection was recorded in panels with concrete capping. Cracking modes in panels reinforced with 6mm mild steel were controlled by material failure while those in panels with 9mm high yield steel, cracks was only observed at the lower part of the capping.

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Numerical analysis on seismic behavior of a novel sandwich wall system

E3S Web of Conferences ◽

10.1051/e3sconf/201913604071 ◽

2019 ◽

Vol 136 ◽

pp. 04071

Author(s):

Zhao-yan Tian ◽

Qun Xie

Keyword(s):

Sandwich Panel ◽

Residential Buildings ◽

Steel Wire ◽

National Policy ◽

High Strength ◽

Wire Mesh ◽

Sound Insulation ◽

Foamed Concrete ◽

Sandwich Wall ◽

Wall System

Concrete sandwich panel is a kind of building element with the characteristics of light weight, high strength, suitability for standardized production, meanwhile it has the multi-function of heat preservation and sound insulation which can be used not only as enclosure components, but also as structural components for multi-story residential buildings. A novel sandwich wall system has been presented in this work with an innovative design concept. Compared with traditional steel wire sandwich panel, this sandwich panel wall system has unique features such as prefabricated steel system, core column with spiral stirrup, foamed concrete as insulation layer. This wall system also meets the national policy requirements in energy-saving and has potential application and development prospects. In this paper, Finite element method is used to simulate and analyze the seismic performance of this new sandwich wall panel. The results show that the panel with 3D steel wire has greater stiffness and better earthquake resistance than panel with planar steel wire mesh.

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Precast Lightweight Foamed Concrete Sandwich Panel (PLFP) Tested under Axial Load: Preliminary Results

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.1153 ◽

2011 ◽

Vol 250-253 ◽

pp. 1153-1162 ◽

Cited By ~ 13

Author(s):

Noridah Mohamad ◽

Wahid Omar ◽

Redzuan Abdullah

Keyword(s):

Axial Load ◽

Sandwich Panel ◽

Load Capacity ◽

Slenderness Ratio ◽

Axial Loading ◽

Load Test ◽

Insulation Layer ◽

Percentage Difference ◽

Steel Bars ◽

Foamed Concrete

A study is carried out to develop a Precast Lightweight Foamed Concrete Sandwich Panel, PLFP, as a new and affordable building system. Experimental investigation to study the behaviour of the panel under axial load is undertaken. The panel consists of two lightweight foamed concrete wythes and a polystyrene insulation layer in between the wythes. The concrete panels are reinforced with 9mm diameter high tensile steel bars. The rebars are tied to each other through the insulation layer by shear connectors which are made of 6mm mild steel bars bent to 45º angle. Total number of four specimens was tested with one specimen; PA1 was cast without capping at both ends. It was used as a pilot test. The other three specimens are capped with normal concrete at both ends to avoid end crushing during axial loading. Axial load test was conducted and the results are presented here, which include the ultimate load capacity, crack pattern and failure mode, strain distribution and load-deflection curve of the panels. The experimental ultimate strength achieved recorded lesser percentage difference with the formulae by Pillai and Parthasarathy when compared to formulae in BS8110. It is also observed that the strength of the panels are affected by the compressive strength of the foamed concrete forming the wythes, the presence of concrete capping at panel’s ends and the slenderness ratio, H/t. Specimens with capping at both ends recorded higher ultimate loads with no premature crushing. Failure of panels with slenderness ratio, H/t < 18 were by premature buckling near the supports whereas for panels with higher H/t ratio, slight bending was observed in the middle zone. The results also indicate that a certain degree of compositeness is achieved between the wythes.

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Development of the universal tool for testing of tensile properties of hexagonal steel wire mesh for civil engineering

Metallurgical and Materials Engineering ◽

10.30544/365 ◽

2018 ◽

Vol 24 (2) ◽

pp. 113-122

Author(s):

Ivana Atanasovska ◽

Dejan Momčilović ◽

Milorad Gavrilovski

Keyword(s):

Tensile Properties ◽

Civil Engineering ◽

Steel Wire ◽

Strength Properties ◽

Wire Mesh ◽

Repeated Testing ◽

Element Analysis ◽

Safety Testing ◽

Steel Wire Mesh ◽

Wire Meshes

The developing of the universal tool for testing of tensile properties of hexagonal steel wire mesh for civil engineering is described in this paper. The developed tool allows repeated testing of hexagonal steel wire mesh of different dimensions without tool changes and is generally related with the procedure for the determination of tensile strength properties of different wire meshes. The construction of the tool which is related to the aims of the decreased mass consumption and high operation safety is described in detail. Particular attention is focused on the safety component of the tool which ensuring safety testing by preventing slipping of the wire mesh samples during loading. The paper also presents the Finite Element Analysis performed in order to verify the high safety factor of the developed tool. The contact regions with stress concentration behavior are analyzed by non-linear solvers. The obtained results and conclusion about the possible contributions of the developed universal tool for extensively testing of wire meshes for civil engineering are discussed.

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High Temperature Performance of a prefabricated concrete sandwich panel

E3S Web of Conferences ◽

10.1051/e3sconf/202123303028 ◽

2021 ◽

Vol 233 ◽

pp. 03028

Author(s):

Shouqian Liu ◽

Zhan Song

Keyword(s):

High Temperature ◽

Sandwich Panel ◽

Precast Concrete ◽

Wire Mesh ◽

Steel Bar ◽

Concrete Layer ◽

Core Column ◽

Sandwich Wall ◽

Strength And Stiffness ◽

Sandwich Wall Panel

The innovative sandwich wall panel studied in this paper can be used as the load-bearing member of the structure. In addition to the traditional sandwich panel structure, the new panel system also has the characteristics of spiral stirrups along the section of the core column, 650mm column spacing, foam concrete for insulation layer and self-compacting concrete for outer layer. In addition, in order to improve the overall strength and stiffness of the panel, a unique wire system consisting of two vertical wire mesh connected by a short horizontal steel bar is adopted in the concrete layer. In order to study the mechanical properties of the new panel system at high temperature, ABAQUS simulation was carried out. The simulation results show that the new precast concrete sandwich wall system has good resistance to high temperature and still has good bearing capacity after high temperature.

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Cyclic Behavior of Beam-Column Connections in Precast Structures

Frontiers in Built Environment ◽

10.3389/fbuil.2021.639778 ◽

2021 ◽

Vol 7 ◽

Author(s):

Hilal Meydanli Atalay ◽

Sevket Ozden

Keyword(s):

Mild Steel ◽

Precast Concrete ◽

Spring Steel ◽

Superior Performance ◽

Cyclic Behavior ◽

High Yield ◽

Moment Capacity ◽

Moment Resisting ◽

Post Tensioning ◽

Precast Structures

The performance of precast concrete structures is greatly influenced by the response of beam–to-column connections. In this study, a new moment resisting precast concrete beam-column connection detail with post-tensioning bolts, made out of high yield strength spring steel, has been experimentally investigated as an alternative to the conventional precast moment resisting connections. Precast specimens and an aseismic monolithic reference specimen have been tested under reverse cycling loads. The contribution of the mild steel in the connection region to the flexural moment capacity, and to the initial pre-stressing force on post-tensioning bolt have been the main test variables. The moment capacity, stiffness, energy dissipation capacity and the residual displacement performance of the precast connections have been compared with those of the aseismically detailed monolithic connection. The conducted tests reveal that the connection detail with steel corbel along with the post-tensioning bolt and mild steel has superior performance properties as compared to the companion precast specimens.

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