Precast concrete wall panels

Traditional concrete structures are frequently linked to poor energy efficiency and substantial heat loss, which pose significant environmental issues. To enhance thermal insulation and reduce heat loss, the use of precast insulated walls is suggested. This research introduces a new energy-efficient precast concrete panel (PCP). We explored various material combinations, including air bubbles, nano microsilica compound (NMC), nano microsilica powder (NMP), and latex, to determine the most effective formulation. A total of 99 tests were performed to assess the compressive strength of the samples, with 28 tests selected for thermal conductivity evaluations at temperatures of 300 • C and 400 • C based on satisfactory compressive strength results. The results indicated that the optimal mix of 4% air bubbles and 13% NMC achieved the lowest thermal conductivities of 1.31 W/m•K and 1.20 W/m•K at 300 • C and 400 • C, respectively, showing improvement ratios of 7% and 15.5% compared to the baseline tests. Additionally, the tests that included latex did not meet the thermal conductivity standards. The optimal combinations identified in this research can be effectively utilized in PCPs, resulting in significant energy savings. It is expected that stakeholders in the green building sector will recognize these proposed PCPs as a practical energy-efficient solution to advance sustainable and environmentally friendly construction practices.

The plastic waste of PET (Polyethylene Terephthalate) can be an alternative replacement of coarse aggregate materials in the lightweight concrete is environmentally friendly. The study purposes were determined the value of flexural strength of concrete mix with coarse aggregate of plastic waste of PET with the addition of silica fume and steel fibers with the reinforcement addition of wiremesh. The study method was used experimental method. The testing on the fine aggregate, coarse aggregate and wiremesh were conducted as a preliminary test to determine the feasibility of the material. The planning of concrete mix design was used Dreux-Corrise method. Wiremesh was used the diameter of 1.55 mm with reinforcement spacing of 2.5 cm. The silica fume percentage were used by 10% of the cement weight and steel fibers was used the bendrat wire. Panel-shaped test specimens measuring 50 cm of long, 30 cm of wide and variations in thickness of 3 cm and 5 cm respectively amounted to 3 pieces. Based on the analysis of flexural strength calculations, the average of flexural strength of the concrete test specimen with a thickness of 3 cm theoretically is 110.438,9677 N.mm and according to the results of laboratory testing is 376.667 N.mm. While the average of flexural strength of the concrete test specimen with a thickness of 5 cm theoretically is 316.177,8184 N.mm and according to the results of laboratory testing is 573.330 N.mm.

Malik Thanoon for their useful comments and suggestions. Author also would like to send his sincere gratitude to Dr. Mohd. Saleh Jaffer for his help in providing books and journals. Author wishes to thank the technical staff of Concrete and Structure Laboratory Tuan Hj. Gazali Said. En. Halim ,En. Nayan Din and En. Baharuddin for their kind assistance rendered. Further , author like to thank to Department of Civil Engineering ,National University of Malaysia (UKM) for allowing him to use the necessary equipments for the research and also to the Jurueteknik Kanan En. Ghani and other technicians for helping him in conducting tests even on Sundays and public holidays. VI I certify that an Examination Committee met on 10 th August 2002 to conduct the final examination of Aftab Ahmad on his Master of Science thesis entitled "Durability Study of Precast Concrete Sandwich Panel Under Exposure to Sea Water" in accordance with the Universiti Pertanian Malaysia (Higher Degree) Act 1980 and Universiti Pertanian Malaysia (Higher Degree) Regulations 1981. The Committee recommends that the candidate be awarded the relevant degree. Members of the Examination Committee are as fo llows

Ao meu Pai e Eterno Deus, que tantas bênçãos tem me concedido. Ao meu marido, Edmilson, que me ensinou a acreditar em mim mesma. Aos meus pais, Dorgival e Rosélis, que sempre acreditaram que a maior herança que se pode dar a um filho é a instrução. 3 AGRADECIMENTOS A Deus que me deu o CONHECIMENTO para ser alcançado, a SABEDORIA para discernir o melhor caminho e a FÉ para continuar apesar das dificuldades, Ao Professor José Ricardo Queiroz Franco, pela orientação, pela exigência, pela compreensão e pelo apoio. Ao meu marido, Edmilson, pelo seu AMOR, pelo grande apoio e pela enorme paciência. Ao meu pai pelas longas revisões, discussões, questionamentos e orientações. À minha mãe pelo apoio SEMPRE. Ao meu irmão pelo seu exemplo e interesse. À Renata e ao Marcelo pela valiosa ajuda, pela seriedade e pelo empenho nos trabalhos. A Rosália pela companhia, pelo apoio e troca de experiências. A todos do CADTEC pelo espírito de equipe sempre presente, por suas contribuições para este trabalho e para o crescimento do conhecimento do grupo como um todo. Ao Professor Mounir Khalil El Debs por gentilmente ceder várias figuras de seu livro para inserção neste trabalho. Aos demais colegas, professores e funcionários do DEES/UFMG, que, de alguma forma, colaboraram para o desenvolvimento desse trabalho.

Bahan agregat kasar ringan yang digunakan merupakan limbah kayu bengkirai dari pengrajin kusen pintu dan jendela. Penelitian ini bertujuan mengetahui seberapa besar pengaruh penggunaan agregat Kayu Bengkirai terhadap berat volume, kuat tekan, kuat tarik belah dan modulus elastisitas beton, serta mendapatkan variasi optimal dari variasi jumlah agregat Kayu Bengkirai. Perhitungan campuran beton mengunakan metode SNI  7656-2012 dengan kuat tekan rencana 22,5 MPa. Variasi campuran  agregat Kayu Bengkirai yaitu sebesar  90%, 100% dan 110% dari banyaknya agregat kasar yang digunakan, serta dibuat beton normal sebagai pembanding. Benda uji yang dibuat berbentuk slinder dengan  diameter 15  cm dan tinggi 30 cm.  Dari penelitian,  didapat hasil  berat volume beton ringan dengan agregat Kayu Bengkirai  berkisar antara 1737-1788 kg/m3 lebih ringan dari beton normal yaitu 2361 kg/m3. Nilai kuat tekan rata-rata beton ringan dengan agregat Kayu Bengkirai berkisar 11,04-12,55 MPa lebih kecil dari ...

Industrialised Building System (IBS) is a term used in Malaysia to denote precast construction method arising from the demand in shifting the realm of conventional construction method into the era of automation. Precast concrete wall panels with opening are important structural elements in buildings because openings are created in the wall panels for the provision of doors, windows as well as services purpose. This paper reviews the design and the test results of precast concrete wall panels with opening on both load bearing and shear walls. The design parameters highlighted are the boundary conditions, geometric characteristic and the configuration of size and the location of the opening on wall panels. In general, the openings in a wall panel affect its structural behaviour.

This paper presents the study of service stress appear in various structural elements in the design of medium rise reinforced concrete building in Sri Lanka using selected codes. Five structural design codes have been considered for the study. Namely EN1992:2004, BS8110:1985, IS456:2000, AS3600-2009 and ACI318-2014. Comparisons of the provisions for actions, and for the resistance of sections in flexural and axial loading are carried out. The differences in the service stress in respective designs have been estimated and reported. Keywords— service stress, reinforced concrete, medium rise building.

A method was described of ultimate strength calculation of compressed steel panels proposed for shipbuilding applications. The calculations consist in applying Finite Element Method (FEM) to a model composed of finite shell elements. Large displacement values and plastic flow of material are taken into consideration. Results of ultimate strength calculations of an example panel under compression were compared with those from experimental tests. Accuracy of a proposed simple method of ultimate strength assessment based on the longitudinal bending theory of rod with initial deflections, was also investigated.

COMPDYN 2019 is one of the 32 Thematic Conferences of the European Community on Computational Methods in Applied Sciences (ECCOMAS) to be held in 2019 and is also a Special Interest Conference of the International Association for Computational Mechanics (IACM). The purpose of this Conference series is to bring together the scientific communities of Computational Mechanics, Structural Dynamics and Earthquake Engineering, to act as the forum for exchanging ideas in topics of mutual interests and to enhance the links between research groups with complementary activities. We believe that the communities of Structural Dynamics and Earthquake Engineering will benefit from their exposure to advanced computational methods and software tools which can highly assist in tackling complex problems in dynamic and seismic analysis and design, while also giving the opportunity to the Computational Mechanics community to be exposed to very important engineering problems of great social interest. The COMPDYN 2019 Conference is supported by the National Technical University of Athens (NTUA), the European Association for Structural Dynamics (EASD), the European Association for Earthquake Engineering (EAEE), the Greek Association for Computational Mechanics (GRACM). The editors of this volume would like to thank all authors for their contributions. Special thanks go to the colleagues who contributed to the organization of the Minisymposia and to the reviewers who, with their work, contributed to the scientific quality of this e-book.

The reinforced concrete (RC) constructions built after World War II represent almost half of the European building stock. Such buildings are characterized by low energy efficiency, living discomfort, and may be inherently vulnerable to seismic actions, having been designed before the enforcement of modern building codes. A multi-purpose retrofit strategy addressing in particular both energy and structural issues is therefore necessary. The present paper considers the sole seismic retrofit interventions by investigating the suitability of external RC walls hinged connected at their base, suitable to improve the seismic performance of poorly detailed existing RC buildings. In particular, such a solution avoids the concentration of deformation at one storey of the building, i.e. the development of soft story mechanisms, and reduces the demand on the foundations of the new system, being the bending moment at the base of such walls nearly zero. The paper shows, through non-linear pushove...

Lightly reinforced concrete walls are commonly found in low-to-moderate seismic regions such as Australia. While many theoretical analyses on lateral load–displacement of structural walls have been proposed and widely used, not many have been developed for lightly reinforced concrete walls. The lateral load–displacement behaviour and failure mechanism of lightly reinforced structural walls differ to those of heavily reinforced concrete walls, particularly in terms of tension stiffening effects, possible failure mechanisms and drift capacities. An analytical study on lightly reinforced rectangular concrete walls is presented in this paper. A parametric study was conducted to provide initial insight into the effect of four design parameters (aspect ratio, axial load ratio, transverse reinforcement ratio and longitudinal reinforcement ratio) on the ultimate displacement capacity of reinforced concrete walls. Two analytical models were developed to predict the lateral load–displacement ...

The interaction between cladding panels and the main structure is a crucial point to assess the seismic response, and above all the structural safety, of RC precast industrial building. In the past, connections were often designed to allow construction tolerances and to accommodate both thermal and wind-induced displacements. The lack of specific details to allow relative in-plane displacements between cladding panels and the main structure often led to the participation of cladding panels in the structure seismic-resistant system with consequent connection failures. In the last decades, a lot of experimental tests were performed to investigate the in-plane performance of panel connections, and some design recommendations have been developed accordingly. In the out-of-plane direction, the connections were often considered to be infinitely rigid and not to suffer any damage by the seismic load. This work deals with the out-of-plane response of panel-to-structure connections for verti...

This paper presents the results of an experimental program on precast reinforced concrete wall panels (PRCWP). These panels were damaged under cyclic lateral loads and thereafter retrofitted or rehabilitated and retested. The experimental program was conceived to analyse the possibilities of using FRP materials for strengthening the PRCWP affected by seismic action. The fibre reinforced polymer (FRP) composites are frequently used in strengthening structural elements because of their superior characteristics and simple technology. The existing literature lacks information concerning reinforced concrete walls (RC) retrofitted by FRP composites compared to other structural members. This paper presents various effective strengthening solutions that can be applied to damaged elements. The retrofitting solutions consist in use of EBR-CFRP strips, combined EBR-CFRP strips with NSM-CFRP plates, textile reinforced mortar (TRM) using glass fibre grid, and TRM using carbon fibre grid. The solutions were proposed with the aim of restoring the wall shear resistance and to provide the confinement effect at the ends. The experimental results indicate that the performance of the elements, repaired and strengthened, were almost equal to or higher than the reference elements in terms of load bearing capacity, stiffness and energy dissipation capacity. A more ductile behaviour compared to the reference elements was recorded for the rehabilitated and retrofitted elements.

Concrete is a construction material favored by most people because it has many advantages, however, concrete also has some disadvantages. One way to overcome the weaknesses that have concrete is to use precast concrete technology and the use of lightweight concrete, as it can increase the efficiency of the execution time of jobs and security of buildings against earthquake hazards. On the wall of multistory buildings are non-structural components of the wall where the burden should be borne by the structural elements so that the weight of the wall effect on the planning dimension of structural elements. This study aimed at generating technology in making lightweight precast concrete wall (wall panel), by providing a cavity in the longitudinal cross section of concrete, and assess its feasibility as a wall material. Manufacture of lightweight precast concrete with a thin cavity current is likely carried out considering the technology has been the discovery of self compacting concrete (SCC) is concrete without gravel with self compacting.

Many reasons such as the Industrial Revolution and the need for rapid building production after the Second World War have led to an acceleration of developments in the construction sector and new construction systems have emerged. These construction systems have brought forth the need for new facade designs. Prefabricated facade panels designed with the aim of quickly closing a building whose structure is completed so that it is least affected by external environmental conditions and ensuring that the facades created can exhibit good performance are also among these innovations. In this study, thermal and sound insulation, and fire resistance performance characteristics of prefabricated facade panels with wood, concrete, metal, or terracotta-based structure material, made with three different design concepts as massive, sandwich, and frame, were examined. The study is considered important because it examines the characteristics of facade elements aimed at improving the quality of the indoor environment.

The present study was conceived in order to investigate the shear behaviour of the Precast Reinforced Concrete Wall Panels (PRCWP) with cut-out openings subjected to in-plane seismic loading conditions and to assess the shear capacity gain obtained using Fiber Reinforced Polymer (FRP) composites as retrofit solution. The structural system of Precast Reinforced Concrete Large Panels (PRCLP) was extensively used in Romania, from 1950 to 1990, for housing buildings with 5 and 9 stories [1]. Cut-out openings are often required to facilitate direct access from outside or between adjacent apartments, predominantly at the ground floor, where both gravity and seismic capacity demand is maximum. However, cut-out openings performed in structural walls results in the modification of the internal force flow paths, loss of load bearing capacity and reduced structural safety.
Similar experimental researches are scarce in the literature. The earthquake resisting behaviour of Reinforced Concrete (RC) structural walls with openings, strengthened by Carbon FRP (CFRP) sheets and grids, was investigated in the post-damage repair and strengthening case [2]. The shear and flexural strengthening effect of differently oriented CFRP sheets was examined on cantilever type RC shear walls in both prior-to-damage and post-damage situations [3]. Experimental research was performed on high slenderness RC walls with door openings distributed on four height levels, strengthened with CFRP sheets [4].

A strengthening solution for multi-storey buildings in seismically active regions is considered. The Precast Reinforced Concrete Large Panel (PRCLP) structural system is described. Besides earthquakes, different problems during the last decades were identified in the PRCLP structural behaviour: design mistakes, neglected health monitoring, construction problems, change of use for example cut-out openings. The presented study is a part of an ongoing research program which deals with the influence of the Fibre Reinforced Polymer (FRP) strengthening on the behaviour of Precast RC Wall Panels (PRCWP) with cut out openings subjected to cyclic (seismic) and normal (gravity) loading. In this paper a brief literature survey concerning RC walls strengthened by FRP is presented and the experimental tests setup is discussed. The wall specimens were designed according to the 1981 Romanian code. Tests are described and a discussion based on previous experimental work on shear walls is undertaken and future research is suggested.

Stay-in-place (SIP) formwork is a more-practical alternative to traditional steel or wood formworks due to its improved constructability and durability. The aim of this paper was to study the fire resistance performances of structural and non-structural concrete panels with polyvinyl chloride (PVC) SIP formwork. Three 124.01 in × 110.24 in × 3.15 in panels of PVC SIP formwork were tested and compared to one another. All panels were aged for 28 days, then exposed to the standard fire curve based on the ISO 834:2014 standard, and the temperatures in each panel surface recorded. The results indicate that concrete strength significantly influenced the structural stability and the fire resistance time of the panels (under load), even in this type of panels when exposed to high temperatures. It was found that the PVC encasement enhanced the thermal insulation property, one of the fire resistance performance criteria. Overall, the importance of this alternative formwork is the reduction in the use of forest resources, the raise of awareness of their conservation, and the promotion of their rational use as this a material is friendly to the environment.

Most of the available shear models for reinforced concrete rely on empirical formulations. In this study, a rational shear stress function is used to define the shear stress–strain envelope for reinforced concrete. Cyclic rules are proposed to define the loading, unloading and reloading relationships for reinforced concrete under shear stress reversals. A normal stress function describing the cyclic relationship of concrete under axial stress is also introduced. The proposed functions are verified using experimental data of reinforced concrete panels tested under monotonic and cyclic loading. Subsequently, the normal and shear stress functions along with their cyclic rules are integrated in a non-linear finite element analysis code. The resulting model accounts for tension stiffening, crack opening and closing, compression hardening and softening, degradation of concrete strength and stiffness in the direction parallel to the crack, compression unloading and reloading, as well as no...

Stay-in-place (SIP) formwork is a more-practical alternative to traditional steel or wood formworks due to its improved constructability and durability. The aim of this paper was to study the fire resistance performances of structural and non-structural concrete panels with polyvinyl chloride (PVC) SIP formwork. Three 124.01 in × 110.24 in × 3.15 in panels of PVC SIP formwork were tested and compared to one another. All panels were aged for 28 days, then exposed to the standard fire curve based on the ISO 834:2014 standard, and the temperatures in each panel surface recorded. The results indicate that concrete strength significantly influenced the structural stability and the fire resistance time of the panels (under load), even in this type of panels when exposed to high temperatures. It was found that the PVC encasement enhanced the thermal insulation property, one of the fire resistance performance criteria. Overall, the importance of this alternative formwork is the reduction in the use of forest resources, the raise of awareness of their conservation, and the promotion of their rational use as this a material is friendly to the environment.

Tests on infill masonry walls have been widely performed by many researchers and for a long time with the main purpose of characterising the infill performance under earthquake-type excitations. However, most of these works deal with laboratory tests on purpose-built specimens. More recently, vibration-based tests have been also adopted to investigate the influence of the non-structural elements on the dynamic behaviour of buildings, with the advantage that this kind of tests can be performed both on laboratory specimens and on in-situ buildings. However, differently from classical infill tests (i.e., monotonic or cyclic lateral load tests, out of plane tests, etc.), a limited number of works is available in the literature discussing the outcomes and possible procedures for testing infilled structures with vibration-based methods aimed to investigate the role of the non-structural components. This paper presents a literature review of research works dealing with vibration-based test...

Experimental studies on the behaviour and performance of prestressed natural stone hollow panels were performed using prestressing wires as internal tendons to apply a compression force to pre-assembled dimension stone slabs forming the panels. Six prototypes were subjected to three-point bending and vibration tests, and the effect of filling the panel void with polyurethane and of the prestressing intensity was also studied. Dynamic tests were performed to obtain the panel's self natural period of vibration and the natural stone's Young's modulus. Static load tests were performed to ascertain the panels' suitability for application as stand-alone façade panels. The experimental results revealed two distinct failure modes after cracking, depending on whether polyurethane infill was injected into the void. The postrupture behaviour was analysed taking into account the favourable effect of filling the panel void with polyurethane foam. Finite element computer analyses of the stress states induced in the panels were also carried out for three different geometries. Data obtained from specimens subjected to the same load regime were compared.

The application of precast concrete in recent days has been tremendously used in building constructions, especially in constructing multi-story buildings. This is due to the rapid construction time, cost savings, and minimalisation of waste from formwork usage. The XYZ Project used precast components made of reinforced concrete and fabricated by XXX workshop Bogor branch. This study aims to evaluate the stages that must be considered in installing the precast components at the building facades. The stages were initiated from the reinforcement installation up to the concrete pouring in the XXX workshop and delivery process. One delay factor in the XYZ project was the error in the delivered parts. The on-site checking of precast components before installation conformed to the work method. The benefit of the precast component application in the XYZ project was the construction time acceleration, which was in total it spent about 310 days with 700 units of precast components spread in the various points.

Floor diaphragms play several roles in the seismic response of dual systems: support vertically spanning components, transfer lateral forces to walls and frames, provide restraint to columns and walls, tie the structure together, and enable redundant load paths for lateral forces. In many buildings after events as recent as the 2010-2011 Christchurch earthquakes, floor diaphragms were unable to perform one or more of these functions, leading to extensive damage and collapse. Research consistently highlights three underlying causes: a failure to ensure the integrity of the load path, underestimation of in-plane forces, and poorly understood interactions with walls, supporting beams and RC moment frames. Most recent and ongoing research has focused on modifying the prescriptive code provisions, and indeed many codes-but not all− have been consequently updated. Such prescriptive rules, however, are not helpful for assessing existing buildings, comparing alternate means and methods, or in displacement-based design (DBD) for which a performance-based design (PBD) framework is necessary. This paper proposes a new performance-based framework for the seismic design of reinforced-concrete (RC) floor diaphragms with or without precast elements. The floor diaphragm performance limit states (LS) are redefined in terms of the observed failure modes (FM). Results from prior research on these failure modes are used to select damage measures (DM, e.g. 'crack width') for pairs of FM and LS. Expressions for DMs in terms of engineering demand parameters (EDP, e.g., 'strain') are derived from experimental results or from first principles. EDPs are the basic output from numerical analysis in PBD; this paper comments on the suitability of different analytical approaches.

The use of steel fiber-reinforced concrete (SFRC) for low-rise walls in low-seismicity regions is evaluated experimentally. Shake-table tests of SFRC and conventionally reinforced concrete walls with an aspect ratio of 1.0 under several ground motions to failure were conducted. Main variables studied were fiber aspect ratio (64 and 80) and fiber volume content (0.55%, 0.75%, and 1%). Wall performance is assessed in terms of crack patterns, failure modes, lateral resistance and hysteretic response. The results showed that SFRC walls exhibited superior performance than that observed for the wall with welded wire reinforcement in the web. Furthermore, SFRC walls containing 0.75% or 1% fiber volume content exhibited a response that was as good as that observed for the wall reinforced with deformed bars as web reinforcement in terms of lateral strength and drift capacity.

Stay-in-place (SIP) formwork is a more-practical alternative to traditional steel or wood formworks due to its improved constructability and durability. The aim of this paper was to study the fire resistance performances of structural and non-structural concrete panels with polyvinyl chloride (PVC) SIP formwork. Three 124.01 in × 110.24 in × 3.15 in panels of PVC SIP formwork were tested and compared to one another. All panels were aged for 28 days, then exposed to the standard fire curve based on the ISO 834:2014 standard, and the temperatures in each panel surface recorded. The results indicate that concrete strength significantly influenced the structural stability and the fire resistance time of the panels (under load), even in this type of panels when exposed to high temperatures. It was found that the PVC encasement enhanced the thermal insulation property, one of the fire resistance performance criteria. Overall, the importance of this alternative formwork is the reduction in the use of forest resources, the raise of awareness of their conservation, and the promotion of their rational use as this a material is friendly to the environment.

Lightly reinforced concrete walls are commonly found in low-to-moderate seismic regions such as Australia. While many theoretical analyses on lateral load–displacement of structural walls have been proposed and widely used, not many have been developed for lightly reinforced concrete walls. The lateral load–displacement behaviour and failure mechanism of lightly reinforced structural walls differ to those of heavily reinforced concrete walls, particularly in terms of tension stiffening effects, possible failure mechanisms and drift capacities. An analytical study on lightly reinforced rectangular concrete walls is presented in this paper. A parametric study was conducted to provide initial insight into the effect of four design parameters (aspect ratio, axial load ratio, transverse reinforcement ratio and longitudinal reinforcement ratio) on the ultimate displacement capacity of reinforced concrete walls. Two analytical models were developed to predict the lateral load–displacement ...

h i g h l i g h t s EBR and EBROG methods have been utilized to install the FRP sheets on deep beams with openings. EBROG is the most effective method in preventing the debonding of sheets. The inclined orientation of sheets is the most effective configuration among the installation methods.

Many reasons such as the Industrial Revolution and the need for rapid building production after the Second World War have led to an acceleration of developments in the construction sector and new construction systems have emerged. These construction systems have brought forth the need for new facade designs. Prefabricated facade panels designed with the aim of quickly closing a building whose structure is completed so that it is least affected by external environmental conditions and ensuring that the facades created can exhibit good performance are also among these innovations. In this study, thermal and sound insulation, and fire resistance performance characteristics of prefabricated facade panels with wood, concrete, metal, or terracotta-based structure material, made with three different design concepts as massive, sandwich, and frame, were examined. The study is considered important because it examines the characteristics of facade elements aimed at improving the quality of th...

This paper presents experimental and numerical investigations on the behaviour of axiallyloaded concrete walls restrained on three sides (TW3S walls). Particular emphasis was given to the influences of varying the slenderness ratio, aspect ratio, concrete strength, and eccentricity on the ultimate axial strength of TW3S walls. Because of the overly conservative nature of the code design equations and the scarcity of other available models for estimating the ultimate axial strength of TW3S walls, a more encompassing design equation has been developed. Comparisons with the test data of the current and previous studies confirmed that the proposed equation is satisfactory and reliable.

Axially loaded reinforced concrete (RC) walls can be designed using simplified design methods given in codes such as the Australian Concrete Standard (AS3600-09) and the American Concrete Institute Code (ACI318-14). The ACI318-14 equation is intended for load bearing walls supported at top and bottom only. The AS3600-09 includes effective height factors to distinguish the effect of various support conditions, and also allows for higher concrete strengths and new guidelines not provided in the previous release, AS3600-01. However, these practical equations are based on empirical models and their scope of application is still limited. Recent research has been undertaken on the applicability of more reliable and accurate wall design methods. This paper initially presents a derived numerical technique incorporated in a computer program (WASTABT), to implement the iterative analysis for concrete walls with various support conditions. The outputs from the WASTABT program are verified using the results obtained from previous experimental results. A parametric study is then conducted using the verified computer-based numerical technique to analyse axially loaded RC panels. The study focuses on the effect of varying panel properties such as wall dimensions, concrete strengths, eccentricities and reinforcement ratios, along with varying support conditions.

This research is presented experimental and numerical investigations of composite concrete-steel plate shear walls under axial loads to predicate the effect of both concrete compressive strength and aspect ratio of the wall on the axial capacity, lateral displacement and axial shortening of the walls. The experimental program includes casting and testing two groups of walls with various aspect ratios. The first group with aspect ratio H/L=1.667 and the second group with aspect ratio H/L=2. Each group consists of three composite concrete -steel plate wall with three targets of cube compressive strength of values 39, 54.75 and 63.3 MPa. The tests result obtained that the increase in concrete compressive strength results in increasing the ultimate axial load capacity of the wall. Thus, the failure load, the corresponding lateral displacement and the axial shortening increased by increasing the compressive strength and the rate of increase  in failure load of the tested walls  was about...

h i g h l i g h t s Three empirical equations are proposed to estimate the strength capacity of masonry walls. An expression to assess the contribution of masonry tensile strength is also presented. The equations take into account the influence of the main parameters involved on the ultimate capacity of masonry walls. The performance of equations shows good agreement with a selection of experimental results.

Direct incorporation of phase change materials (PCMs) in the mortar matrix increases the effective thermal mass of a structure without increasing the size or significantly changing its weight; thereby reduces the energy consumption and brings comfort/well-being throughout the various seasons. Hence, the effect of direct incorporation of various types of PCMs in a mortar matrix needs to be addressed to optimize PCM addition and its type. In the present study, five different PCMs, two inorganic , and three organics were directly incorporated into the cement matrix from 5 to 15% as partial replacement of cement. Various studies such as compressive strength, flexural strength, acid and sulphate attack, Differential scanning calorimetry (DSC) analysis, Fourier transform infrared spectroscopy, thermal conductivity, stability of PCM (1000 thermal cycle test), thermal performance, and leakage test were conducted. Organic (n-BS, PEG-600, and OM29) PCMs have significantly decreased the strength of cement mortar with a peak reduction of 74% for HS24 (15%); whereas inorganic (HS24 and HS29) PCMs gave considerably equal strength of conventional mortar up to 10 wt%. A statistical technique using Minitab was used to validate the actual experimental values (compressive strength of HS24) with predicted values, and it was observed that the error in experimental values and the predicted values is less than 5% for 28 and 60 days curing thereby showing a confidence level of 95%. Acid attack tests on mortar specimens with PCMs gave a drastic reduction in compressive strength at 90 days. DSC analysis was conducted on all pure PCM materials and found that its temperature range and enthalpy exist in the human comfort zone. The stability for HS24 gave an enthalpy of 145.8 J/g and 122.6 J/g for melting and freezing point after 1000 cycles. The temperature variation of organic PCMs was nearly the same as normal cement mortar, and the maximum reduction of 5 °C was attained with inorganic PCMs. No leakage was observed for HS24, n-BS, and HS29 PCMs.

Many reasons such as the Industrial Revolution and the need for rapid building production after the Second World War have led to an acceleration of developments in the construction sector and new construction systems have emerged. These construction systems have brought forth the need for new facade designs. Prefabricated facade panels designed with the aim of quickly closing a building whose structure is completed so that it is least affected by external environmental conditions and ensuring that the facades created can exhibit good performance are also among these innovations. In this study, thermal and sound insulation, and fire resistance performance characteristics of prefabricated facade panels with wood, concrete, metal, or terracotta-based structure material, made with three different design concepts as massive, sandwich, and frame, were examined. The study is considered important because it examines the characteristics of facade elements aimed at improving the quality of the indoor environment.

The behavior of connection between precast panels is important as it controls the failuremode of the shear wall. Therefore, it is aimed to test the behavior of different type of precastpanel connections in this study. One monolithic reference model and two precast panel modelshaving different horizontal connection details were produced. The behavior of connections wastested under reversed-cyclic lateral loads. It was concluded that welded connections can bedesigned in high and normal ductility levels.

ABSTRAK Pengembangan fly ash berbasis geopolimer sangat cocok untuk memperluas aplikasi pracetak khususnya panel dinding pada lingkungan asam sulfat. Panel berbahan abu terbang ini dapat dijadikan pertimbangan karena memiliki keunggulan diantaranya kekerasan tinggi, ramah lingkungan, tidak menghasilkan gas karbon (CO2), tahan pada temperatur panas antara 600-800° C, tahan lingkungan asam, dan tidak memerlukan perawatan panas. Untuk pembuatan struktur panel pracetak menggunakan bahan pengisi berupa mortar berbahan geopolimer dengan komposisi NaOH 14 M, rasio NaOH/Na2SiO3 sebesar 1 :2, rasio alkaline : fly ash sebesar 35%, dan menggunakan variasi wiremesh sebagai perkuatan, dengan ukuran benda uji panel 800x400x40 mm. Hasil yang didapat kuat tekan umur 1 hari sebesar 11.27 MPa umur 28 hari 60,84 MPa, dengan nilai modulus 28 hari sebesar 13808 MPa. Pengujian kuat tarik 1 hari sebesar 1.02 MPa dan 28 hari sebesar 2,95 MPa Pengujian kuat lentur didapatkan 3,52 MPa tanpa perkuatan dan 4,5...

Wall definition ACI Code Section 2.3 defines a wall as follows: "Wall-a vertical element designed to carry axial load, lateral load, or both, with a horizontal length-to-thickness ratio greater than three, used to enclose or separate spaces." 1-Types of wall (according SDC) (ref. ACI SP17m(14) a-Ordinary reinforced concrete structural walls SDC A, B, C The walls complying with the requirements of chapter 11 b-special reinforced concrete structural walls SDC D, E, F The walls complying with requirements of 18.2.3 through 18.2.8 and 18.10 2-Types of Wall (according loading) Structural walls can be classified as: (a) Bearing walls-walls that are laterally supported and braced by the rest of the structure that resist primarily in-plane vertical loads acting downward on the top of the wall (see Fig. a). The vertical load may act eccentrically with respect to the wall thickness, causing weak-axis bending (b) Shear walls-walls that primarily resist lateral loads due to wind or earthquakes acting on the building are called shear walls or structural walls. These walls often provide lateral bracing for the rest of the structure. (See Fig. b.) They resist gravity loads transferred to the wall by the parts of the structure tributary to the wall, plus lateral-loads (lateral shears) and moments about the strong axis of the wall

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2013Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2013Yapı mühendisliği alanında, yapıların güçlendirilmesi senelerdir tam olarak çözülememiş bir sorun olmuştur. Güçlendirilecek her yapı genellikle farklı özellik gösterebilmektedir. Son depremlerde yapısal hasarlar belirgin şekilde ortaya çıkmış olup geçmişte inşa edilmiş yapıların sismik kuvvetlere dayanacak şekilde projelendirilmesi ve inşası esastır. Yapı hasarlarını azaltmak, ancak dikkatli tasarım yoluyla, ya da hasar görmüş yapılardan dersler alınması ile elde edilebilir. Yapıların depremlerde hasar görmesinin önlemesi amacıyla, yapılarda güvenli tarafta kalacak şekilde kurallar konulmaktadır. Bu bilgiler, yapı onarımı veya yapının inşasında kullanılabilir. Mevcut binanın deprem kapasitesinin artırılması ve göçmesinin önlenmesi esastır. Bu sebeple ele alınan binanın onarım ve güçlendirilmesi çok önemli dır. Bu ...

In this research, the thermal properties of paraffin-impregnated burnt clay aggregate (PIA) concrete were studied. Paraffin was used as a phase change material (PCM) carrier and was incorporated into the burnt clay aggregates using heat and pressure. The compressive and flexural strengths of the concretes and the thermal insulation of the concrete panels were tested. The results of these tests revealed that the strengths and thermal insulation of the standard burnt clay aggregate concrete were improved with the use of PIA. The panels with PIA required more time to reach peak temperature and exhibited a larger drop in peak temperature relative to the control panel without PIA.

The present of the shear connectors with the sandwich composite foamed concrete panel system is to increase the strength of the panel. Therefore the objectives of experiment on effects of the shear connectors spacing is to determine the influence of shear connectors spacing on the axial stress-strain curve, to observe the failure mode sandwich composite foamed concrete panel system with different shear connectors spacing, and to establish ultimate load carrying capacity of different shear connectors spacing. In this study, there are four samples of shear connectors spacing which are 5, 7, 9 and 13 to composited foamed concrete with density of 1400 kg/m3 and 700 kg/m3. This study has showed the enhancement of ultimate compressive strength with increasing numbers of mechanical connectors. The failure of mode observed proved that sandwich panel failures decreasing with enhancement numbers of mechanical connectors, thus sandwich panels can sustained ultimate load carrying capacity.  

A realistic analysis of the reliability of slender high-strength concrete (HSC) columns must include the long-term effects of sustained loads. In this paper, the long-term reliability of eccentrically loaded slender HSC columns under sustained loads is evaluated. The reliability of slender reinforced concrete columns representing normal-strength concrete and HSC is investigated. Since most of the variables involved in column design (material properties, geometric characteristics, loads, etc.) are random, probabilistic methods are used in the analysis. The effects of the concrete compressive strength, amount of longitudinal steel, load eccentricity, and slenderness ratio on the column reliability are investigated. It was found that all these factors have a considerable impact on the resulting column reliability.

This paper presents the structural behaviour of precast lightweight foam concrete sandwich panel (PFLP) under flexure, studied experimentally and theoretically. Four (4) full scale specimens with a double shear steel connector of 6 mm diameter and steel reinforcement of 9 mm diameter were cast and tested. The panel’s structural behavior was studied in the context of its ultimate flexure load, crack pattern, load-deflection profile, and efficiency of shear connectors. Results showed that the ultimate flexure load obtained from the experiment is influenced by the panel’s compressive strength and thickness. The crack pattern recorded in each panel showed the emergence of initial cracks at the midspan which later spread toward the left and right zones of the slab. The theoretical ultimate load for fully composite and noncomposite panels was obtained from the classical equations. All panel specimens were found to behave in a partially composite manner. Panels PLFP-3 and PLFP-4 with highe...

The experimental study presented hereis based on the seismic performance investigation of precast reinforced concrete wall panels (PRCWP), post-damage strengthening using different materials and different anchorage systems. Both wall panels have an initial small window opening, but the second panel has the opening enlarged into a large window opening in order to investigate also the cutout effect. The behavior and failure details are presented and analyzed for both unstrengthened and post-damage strengthened situations. The economic aspect will also be discussed for each of the strengthening systems used.