Wall Panel Specimens Research Articles

Experimental and numerical investigations on the axial compression performance of precast geopolymer concrete sandwich wall panel

This paper investigated a novel precast concrete sandwich panel (PCSP) which made by the geopolymer concrete and enabled by the glass fiber reinforced polymer (GFRP) hexagonal tube connector. Six precast geopolymer concrete sandwich wall panel (PGCSP) specimens were fabricated and tested under axial compression load. The investigating parameters included the connector spacing, panel height, and panel thickness. The failure mode, axial load capacity, load-axial deflection relationship, and load-concrete strain relationship were studied and discussed. Moreover, two-dimensional (2D) finite-element (FE) analysis was conducted to reproduce the test. Parameter analysis was then performed to modify the axial load capacity formula in the Chinese code GB50010-2010. The results indicated that: all specimens exhibited large eccentric compression failure due to the second-order effect, which was caused by concrete crushing and horizontal cracking in the two wythes, respectively; with the decrease of the connector spacing, the crushing area of the specimens would be enlarged, the out-of-plane lateral deformation would be decreased, and the axial load capacity decreased by 17 % and 42 % when the connector spacing changed from 300 mm to 600 mm and 900 mm, respectively; with the decrease of the panel height and the increase of concrete wythes thickness, the axial load capacity of the specimens almost presented a linear increase; the established 2D FE model and the modified formula effectively reflected the axial load capacity of the specimens.

Lateral behavior of wood frame shear wall using PVC wood-plastic composite (WPC) veneer panels

With the growing awareness of environmental protection and green ecology, there has been significant attention on the utilization of new energy-saving and environmentally friendly materials in building structures. This article proposes a novel structure for PVC wood-plastic composite wall panels. The structure comprises Polyvinyl Chloride (PVC) wood-plastic composite materials as the facing panel and SPF (Spruce-Pine-Fir) dimensional lumber as the wall framework, connected using self-tapping screws. In this study, two standard composite wall panel specimens were subjected to testing using both monotonic loading and low-cycle reciprocating loading methods. Finite element models of the composite wall panels were created using ANSYS Workbench software for analysis, investigating the lateral performance of PVC wood-plastic composite wall panels. The analysis results indicate that PVC wood-plastic composite wall panels exhibit favorable shear strength, elastic lateral stiffness, and lateral deformation as shear walls. The shear wall model can be accurately represented in finite element software, with minimal discrepancy between experimental and finite element analysis results. Consequently, the utilization of PVC wood-plastic composite wall panels as shear walls holds promise for future applications in the structural field.

Compressive performance of full-scale GFRP composite sandwich wall panels with wood core

This paper investigated the compressive behaviors of sandwich wall panels consisting of glass fiber-reinforced polymer (GFRP) face sheets and Paulownia wood core experimentally and numerically. Vacuum-assisted resin infusion molding (VARIM) process was used to produce GFRP sandwich wall panel specimens. Four full-scale wall panels with different heights were tested under axial loading to study their failure modes and load-bearing capacities. The results revealed that buckling was the main failure mode of GFRP wall panels under the axial compression and the ultimate load-bearing capacities of specimens were improved the decrease of the height-to-thickness ratio. Experiments showed that decreasing the height-to-thickness ratio from 51.5 to 38.6 can effectively improve the ultimate load-bearing capacities of the wall panels by 124%. The experimental results were compared with finite element analysis (FEA) and analytical results were in good agreement. In addition, an equation was used to predict the load-bearing capacities of the wall panels suitable for the specimens with smaller height-to-thickness ratio.

Method and Experimental Study of Oscillator Frequency Optimization of Distributed Tuned Mass Dampers for Broadband Multimodal Vibration Mitigation of Reinforced Concrete Wall

Distributed tuned mass dampers (dTMD) can effectively mitigate the broadband vibration of a structure. However, when the vibration frequency in question reaches several hundred hertz, traditional optimization methods represented by fixed point theory are difficult to apply due to dense modal density, complex boundary conditions, and vibration inputs. This paper proposes the minimax method based on modal damping to optimize the oscillator’s frequency. Two typical wall panel specimens are tested to evaluate the proposed method. The mode shape of the uncontrolled wall and the vibration mitigation effect of the stacked sandwich-damped TMD under single-point bidirectional excitation is tested. The correlation between the modal damping and the vibration mitigation effect is evaluated. The results show that the RC wall panel has a dense mode when the frequency of interest reaches 300 Hz and above; the distributed stacked sandwich-damped TMDs can effectively mitigate the vibration of the RC wall panel in the frequency range of 200~450 Hz; and that the idea of optimizing the frequency of dTMD based on modal damping is feasible.

Experimental investigation on performance of sandwich wall infill in framed structure

The sandwich wall infill in framed structures is a layered structural system made of thermally insulated core material (EPS layer) with concrete layers on either side reinforced to act monolithically. It is the best replacement for concrete, brick, and hollow block walls because of its low self-weight, few connection joints, and easy and fast installation on site. It also has good thermal and noise insulation properties, a better load-carrying capacity, and was found to be cost-effective. This layered system is resistant to alternate cycles of heat and cold, with less penetration from destructive rays and external forces. For this experimental study, sandwich wall panel specimens (0.75 × 0.75 × 0.1 m) are cast with an external layer of concrete and an Expanded Polystyrene layer as a core, varying its thickness (25 mm, 50 mm, 75 mm), and these layers are bonded together by adequate steel reinforcement. A wall is tested to evaluate its structural performance in the context of ultimate strength capacity, load–deflection profiles, cracking patterns, and failure modalities compared with the conventional wall system. The wall specimen with a minimum core thickness of 25 mm has a maximum load carrying capacity of 504 kN, which attains 98.6% of the ultimate load of a conventional wall specimen, and it also possesses very little deflection of 0.37 mm in the front side of the panel. The maximum strains observed in the concrete layer and reinforced steel bar are 0.0012 and 0.0024, respectively. The current study demonstrates that lightweight sandwich wall panels are a superior replacement for traditional wall systems.

Axial compressive behaviour of cold-formed steel single-stud wall panels with one-sided sheathing and two-sided dissimilar sheathing board configurations: Experimental and analytical study

For practical reasons, it is typical for different types of sheathings (referred to as dissimilar) to be connected at both flanges of the stud (lipped channel-section) in cold-formed steel (CFS) panelized construction (e.g. one side has interior sheathing and the other exterior sheathing). However, limited studies are available on the axial behaviour of CFS studs with different combinations of sheathings present at both-flanges of a stud. This novel experimental study investigates the structural behaviour of nineteen (19) CFS panels with sheathing on one side only and different sheathing on both flanges of the wall panel using combinations of eight (8) different sheathing board types [fibre-cement boards (FCB) (8 mm/10 mm/12 mm thick); calcium silicate boards (12 mm thick); orient strand board (12.5 mm thick); and heavy duty FCB (6 mm/9 mm/12 mm thick)]. Also, first time an attempt is made to study the effect of dissimilar configuration using eight (8) different sheathing board types on axial strength of CFS panels in India. Experimentally tested single stud wall panel specimens consist of; one bare single-stud; eight (8) specimens sheathed with different types of sheathing boards on one flange only; and ten (10) specimens with combinations of different sheathing boards on both-flanges. Average test results are obtained by performing two (02) tests for each specimen. The strength enhancement of a bare single-stud from the sheathing boards has been investigated by testing specimens with a single layer of sheathing at one-flange and combinations of different sheathing boards on both-flanges. The ultimate axial compressive strength, load–deformation behaviour and failure patterns are the parameters compared. A new analytical and semi-analytical design methodologies namely; Rayleigh–Ritz (R-R) method and finite-strip method based on direct strength method (DSM) are adopted for evaluating the axial compressive strength of the CFS wall panels with dissimilar sheathing. Limited studies are available to verify the efficacy of R-R method and DSM to estimate the axial compressive strength of CFS wall panels with dissimilar sheathing on both flanges. Results establish that DSM may be used efficiently rather than the R-R method for axial compressive strength prediction of dissimilar sheathed CFS wall panels. The predicted values show good agreement with the experimental test results, and therefore, demonstrate that the semi-analytical method may be applied efficiently in design.

Experimental test on precast concrete reinforcement connector technology based on strong lapping concept

Experimental test on precast concrete reinforcement connector technology based on strong lapping concept

Seismic Performance Test of Double-Row Reinforced Ceramsite Concrete Composite Wall Panels with Cores

The research objective of this study was the seismic performance of double-row reinforced ceramsite concrete sandwich wall panels. The feasibility of upgrading a new wall panel from a non-load-bearing partition wall to a load-bearing seismic wall was examined by conducting cyclic load tests on five wall panel specimens. The test piece was a sandwich thermal insulation structure that could achieve a good protection distance between the thermal insulation material and the fire source so that the fire prevention problem could be solved. At the same time, the problem of easy fall-off of the insulation system was also solved. The specimens were divided into three groups, including three double-row reinforced ceramsite concrete sandwich wall panels with different dosages of alkali-resistant glass fiber, a double-row reinforced ordinary concrete sandwich wall panel, and a solid concrete ceramic wallboard. The effects of different dosages of alkali-resistant glass fiber, construction forms, and bearing side plate materials on the seismic performance of the sandwich wall panels were investigated separately for the specimens. From the analysis of the specimen results (damage characteristics, hysteresis curves, energy dissipation capacity, bearing capacity, ductility, longitudinal reinforcement strain, and stiffness degradation), it could be seen that among the five types of wallboard, the double-row reinforced ceramsite concrete sandwich wall panel with 0.3% fiber content had the best ductility and energy dissipation capacity. Adding fiber could solve or improve the problem of the low ultimate bearing capacity of ceramsite concrete as the wallboard’s bearing material. Compared with the same size solid ordinary concrete wallboard, the bearing capacity of the double-row reinforced ceramic concrete sandwich panel was slightly reduced. However, the additional seismic performance indexes were relatively superior. Through the analysis of the test results, it was shown that, when considering the thermal performance and seismic capacity, the new wall panel had good prospects for engineering applications.

Thermal, spalling, and mechanical behaviour of various types of cementitious composites exposed to fire: Experimental and numerical analysis

Nowadays, new types of cementitious composites are increasingly being used for the construction of structural members. This poses a problem regarding the structural fire safety design as the thermal behaviour and mechanical properties at high temperatures of these materials are usually not known. The main aim of this paper is to investigate and present the thermal behaviour, propensity to spalling, and residual strength of various types of cementitious composites exposed to fire. Namely, the following materials are investigated: ordinary normal-weight concrete with or without fibres, light-weight aggregate (LWA) concrete with or without fibres, recycled aggregate concrete with or without fibres, LWA concrete with open structure, and two novel cementitious composites – LWA concrete containing crushed textile and foam plastic, and concrete containing mineral wool insulation shreds. Additional aim of this investigation is to resolve whether widely-used simple transport and material models are suitable for numerical simulations of thermal behaviour of unusual cementitious composites. For the purposes of the investigation, experimental program was proposed and executed, and numerical simulations were performed. The experimental program consisted of fire test of wall-panel specimens and cube specimens in a vertical furnace and of measurement of physical and mechanical properties of the investigated materials. The numerical simulations consisted of finite element analysis of temperature evolutions in the wall-panel specimens. The paper summarizes the results and conclusions of the experimental and numerical investigations. Within the paper, compressive strengths and residual compressive strengths of the investigated materials are presented and discussed. Moreover, experimentally measured thermal behaviour is analysed and compared with the thermal behaviour predicted by numerical simulations. In addition to this, spalling behaviour and surface damage of the specimens made of the investigated materials are presented and discussed. The main conclusion of this paper is that widely-used simple heat transport and material models are suitable for numerical simulations of thermal behaviour of various cementitious composites. Additional important conclusion is that concrete containing mineral wool shreds performs very well when subjected to fire.

An energy dissipating hold down device for cold-formed steel structures

A two-phase experimental investigation has been conducted for the development and evaluation of a hold down device that has energy dissipating feature. Focus of the first phase was the development of the device itself, while the second phase concentrated on the investigation of the performance of this device when used in a CFS framed sheathed wall panel that is subjected to reversed cyclic lateral loading. Hold down subassembly test results indicate that the load capacity of the hold downs is mostly limited by the shearing capacity of connection screws. Hold down devices themselves were observed to remain virtually undamaged under tensile loading, indicating a superior mechanical behavior in terms of strength and stiffness. As part of the second phase of the study, cyclic lateral load tests were conducted on seven CFS framed sheathed wall panels in order to study the energy dissipation ability of the proposed hold down device when used in CFS wall systems. Aligned with this focus, the anchor rods used to connect the hold downs to the foundation system in wall panel specimens were altered mainly by reducing the rod diameter within the middle portion over a certain length to provide controlled rod yielding under tensile forces. Controlled yielding of anchor rods was observed to reduce the drift demands imposed on wall panels due to seismic effects, resulting in a minimal damage on wall panels themselves.

KUAT LENTUR PANEL DINDING BETON BUSA DENGAN LAPIS GRC DAN WIREMESH

Lightweight concrete is high in demand as it offers lighter specific gravity which makes the load on the structure smaller. In this research, lightweight concrete was produced by mixing water, cement, sand and foam. Besides aiming to obtain lighter specific gravity, the target of this research was also to design lightweight foam concrete with compressive strength equal to the one of commonly used materials for walls of around 3-5 MPa. However, foam concrete has relatively weaker tensile strength, that it would be inadequate when it has to hold the vertical force of the wall when it is applied as wall panels. This research was conducted to examine the flexural strength of the use of GRC coating and wiremesh for wall panels. Cylinder test was performed using tools with a size of 150 mm in diameter x 300 mm in length to analyze the modulus of elasticity at 28 days old, and three cubical test tools for each variance with a size of 50 mm x 50 mm x 50 were employed to test the tensile strength at 28 days old. A number of wall panel specimens with a thickness of 50 mm, width of 400 mm and length of 800 mm were used to measure the flexural strength. The tests performed in this research resulted in modulus of elasticity of 6856,6 MPa, tensile strength of 0,7 MPa. The flexural strength of wall panels without GRC outer layer and without wiremesh reinforcement was found at 1,5 MPa. Meanwhile, the flexural strength of the wall panel with GRC outer layer without wiremesh reinforcement was found at 4,6 MPa. Finally, the wall panel applied with GRC outer layer and wiremesh reinforcement showed a flexural strength 5,3 MPa.

Experimental Investigation of High Strength Precast Reinforced Concrete Walls used (Vierendeel Truss Form)

This paper presents an experimental investigation to study the behavior of Vierendeel Truss used instead of bearing wall in precast construction. The experimental program contains casting and testing (8) R.C wall panels specimens with opening with right angle corner, the dimension of the opening (300*350*75) mm which it is length, width, and thickness. The dimension of the R.C wall panel specimens was (1000*750*75) mm which they are length, width and thickness, respectively and all the specimens contain cantilever portion (100*60*75) mm length width and thickness respectively. In this study the main variable is the type of concrete and the compressive strength. The wall panel specimens were tested with uniformly distributed load with an eccentricity of (67.5) mm. The specimens were simply supported to represent the supports of the truss. The wall panels were divided into (2) groups, the first group is reactive powder concrete with (4) specimens and the second group is high strength self-compacted concrete with (4) specimens. The failure load, load – deflection curves crack pattern was studied. All the panels were deflected in single curvature in the vertical direction of loading. Opening causes concentrated stress at the corners of opening and initiated the cracks and failure.

Study of shear behavior of grouted vertical joints between precast concrete wall panels under direct shear loading

A precast wall‐type building is constructed by stacking wall panels and slabs. This paper presents a study of the in‐plane shear behavior of vertical grouted joints between precast panels. Thirteen jointed wall panel specimens were tested under direct shear. Based on the results, analytical expressions were developed to predict the shear load versus slip behavior. These can be used in computational models of precast wall type buildings, through modeling of shear springs between the panels. To demonstrate the application, a numerical analysis of an isolated jointed shear wall was performed. The wall was modeled for three cases, (a) monolithic wall, (b) two walls with a gap and (c) two walls with shear links. Based on non‐linear pushover analysis, it was demonstrated that the modeling of jointed walls using shear links reduces the conservatism inherent in a model neglecting the shear transfer across the joint.

Investigation on sheathing effect and failure modes of gypsum sheathed cold-formed steel wall panels subjected to bending

Sheathings and external covering becomes an essential part of the structures, especially when the structure is constructed using cold-formed steel (CFS). Conventionally, the contribution of attached sheathing was ignored in the design of the CFS structural members, but in the recent times, the sheathing effect is being incorporated in the design by American Iron and Steel Institute (AISI) specifications to improve the structural economy. A latest report by AISI titled “Sheathing Braced Design of Wall Studs - RP13-1” covers various sheathing configurations such as non-identical sheathings, single-sided sheathing, and fastener spacings. However, the validation of the AISI report for the flexural loading case is not yet carried out. Hence, a comprehensive investigation has been undertaken in the present work to address the effect of sheathing, associated failure modes, and appropriateness of AISI design specifications, when the sheathed CFS panel is subjected to bending. This paper presents the results of 12 full-scale (2400 mm long) CFS sheathed panels subjected to out-of-plane bending followed by design predictions using the current AISI specifications. Three different CFS studs based on global slenderness values (λe) were investigated with 4 different sheathing configurations. The experimental results indicate that the efficacy of sheathing increases with the increase in global slenderness of CFS studs. In addition, numerical studies of sheathed CFS wall panels based on a simple finite element modeling method suggested by the previous researchers is carried out, and the appropriateness of the model is verified. The design prediction results using the AISI specifications indicates that the effect of sheathing is overestimated, thereby leading to unconservative prediction for most of the sheathed CFS wall panel specimens.

Seismic behavior of reinforced autoclaved aerated concrete wall panels

AbstractVertical reinforced autoclaved aerated concrete (AAC) panel systems are among attractive alternatives for low‐rise buildings. The popularity of AAC panels in building construction is increasing due to their unique material properties, such as being light weight, good insulator, fire resistant combined with having high speed of erection and ease of quality control. However, past experimental evidence on the seismic response of reinforced vertical panels is rather limited with few tests on multi‐panel specimens. To overcome this issue, an experimental program was initiated to test six full‐scale AAC wall panel specimens. In the scope of this study, the in‐plane seismic behavior of AAC vertical load‐bearing wall panels was examined under constant axial load and two‐way cyclic lateral displacement excursions. First, the effect of axial loads on lateral behavior of reinforced AAC walls was investigated. For this purpose, four specimens composed of two and four AAC panels with and without axial loads were tested. Then, the effect of window opening was examined by conducting two more tests. The results of the experiments clearly indicated that the axial loads had a positive effect on the load carrying capacity. The window openings reduced the lateral strength and caused localization of the damage. The ultimate drift of the tested panels was found to be around 1%. The ability of estimating the measured moment versus curvature response of the tested specimens were examined for different adjacent panel assemblages. Finally, the code‐proposed equations to determine the lateral load capacity of AAC walls were critically reviewed in light of the experimental results.

Strength and behaviour of bamboo reinforced concrete wall panels under two way in-plane action

An experimental investigation has been carried out on the use of an environmentally sustainable material, bamboo, in the construction of precast concrete structural wall panels. The strength and behaviour of three prototype bamboo reinforced concrete wall panel specimens under two-way in-plane action was studied. The specimens with varying aspect ratio and thinness ratio were tested to fail under a uniformly distributed in-plane load applied at an eccentricity of t/6. The aspect ratio of the specimens considered includes 1.667, 1.818 and 2 and the thinness ratio includes 12.5, 13.75 and 15. The influence of aspect ratio and thinness ratio of bamboo reinforced concrete wall panels, on its strength and behaviour was discussed. Varnished and sand blasted bamboo splints of 20 mm width and thickness varying from 8 to 15 mm were used as reinforcement in concrete. Based on the study, an empirical equation was developed considering the geometrical parameters of bamboo reinforced concrete wall panels for predicting its ultimate strength under two way in-plane action.

Utilization of Polystyrene Waste for Wall Panel to Produce Green Construction Materials

The wall structure separating floor areas significantly contribute the weight of the building that put it into a greater risk to earthquake event. The use of lighter wall materials is more desirable to reduce the potential risk of damage due to earthquake treat. This development of polystyrene wall panel is an effort to achieve two objectives, namely development light wall material and promoting green construction materials by utilizing polystyrene waste. The paper present the study on the development of polystyrene waste wall panel by pre-compacted method. In this research, the shredded polystyrene was blended with cement Portland and water at various certain proportion. When the mixed already properly blended, it was poured into the steel mold of 30x80cm. The mixed within the mold was subjected to compaction stress for up to 2MPa that reduce the thickness of the mixed into about 1cm. The polystyrene panel was kept in the humid zone for curing for about 28 days. They were 12 wall panel specimens made for this purpose. Result of test show that at the same compaction stress, higher cement content produces stronger polystyrene concrete. The average compressive strength of specimens with 250kg/m3 and 300kg/m3 cement content are 4.9MPa and 5.3 MPa, respectively, and for flexural strength are 2.4MPa and 3.3MPa, respectively. The result show that the compressive strength of concrete matrix and flexural strength panel are significantly high. However, under repeated loading of about 10% of maximum load, the panels experience decrease in stiffness in each load cycles suggesting the low tensile capacity of the concrete matrix. These results indicate the potential use of polystyrene wall panel for construction materials purposes with further attention on improvement the tensile characteristic of the concrete matrix.

Behaviour of non-loadbearing tabique wall subjected to fire – Experimental and numerical analysis

Tabique construction is one of the most used traditional building techniques and it can be found almost everywhere in Portugal with special incidence in the northeast region. Tabique construction elements can be described as a timber structure filled on both sides with an earth-based render. Tabique elements can be found in ancient buildings, from simple construction as rural dwellings to more urban sophisticated ones. This paper presents a study of the behaviour of tabique walls, concerning its fire resistance. Therefore, an experimental analysis was performed using tabique wall panel specimens. Such wall panels were made in pine wood with an earth-based render finishing. In order to assess the thickness effect of the earth-based render on the fire resistance of the wall, three specimens with different render thicknesses of 15mm, 10mm and 5mm were tested in a fire-resistance furnace according to the ISO 834 [1] standard fire curve. Fire resistance is a measure of the ability of a building element to resist a fire, usually the time for which the element can meet appropriate criteria during exposure to a standard fire resistance test. By this way it is possible to increase the safety of people and property. Two performance criteria were verified which are the integrity and the insulation. In addition, a numerical model was also developed in order to assess the tabique wall behaviour under fire conditions, which was validated using the obtained experimental results.

STRUCTURAL PERFORMANCE OF OIL PALM SHELL LIGHTWEIGHT AGGREGATE CONCRETE WALL PANEL ON INSULATION CONCRETE CAPACITY

This paper presents of an investigation conducted the structural performance of oil palm shell lightweight aggregate concrete (OPSLAC) wall panel. Load-deflection characteristic on OPSLAC wall panel was conducted. Further, the effect of Stress-strain relationship and buckling effect on compression load was investigated. The variable selected are size of oil palm shell (OPS). Three wall panel specimens were prepared, and tests on compression load were conducted. The load-deflection result showed the changing on OPS shape used. The convex of OPS influence the bond within aggregate and cement paste. Further, the increasing of compression load is related to the formation and growth of micro cracks. As ultimate strength is approached, increased load and bulk paste micro cracks join to form continuous cracks parallel to the direction of loading on stress-stain curve. After 70% from the ultimate loading, the extent of cracking is so great that OPSLC cannot support additional load.

Seismic strengthening of infilled reinforced concrete frames by CFRP

Abstract The objective of the presented research was to investigate seismic strengthening of non-structural brittle masonry infill walls of reinforced concrete (RC) frames by Carbon Fiber Reinforced Polymers (CFRP). The contribution of CFRP strengthening to the overall behaviour in terms of lateral strength and stiffness, effects of different application techniques and connection details were investigated experimentally and analytically. Experimental work consisted of two parts. The first part included diagonal tension tests of 26 masonry wall panel specimens. These tests were conducted to observe the effects of different CFRP types and applications over the initial stiffness, shear strength and failure modes. In the second part, five one story-one bay RC frames were tested under cyclic in-plane lateral loads. Lateral load-top displacement hysteresis curves and failure modes were obtained. Initial stiffness, peak-to-peak stiffness, equivalent displacement ductility, strength reduction factors, energy dissipation and hysteretic damping values of specimens were evaluated comparatively. A damage table was built for strengthened specimens using experimental observations. In the analytical part, structural models of the CFRP strengthened one story-one bay RC frames were established in order to achieve the generalization of a number of test results. Experimental results and observations were also utilized in this process. Analytical results complied well with the experimental results in terms of lateral load capacity and initial stiffness.