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Increasing the utilisation of hybrid concrete construction in South AfricaHanekom, Rojean 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Hybrid concrete construction (HCC) is a construction technique that makes use of both in-situ and pre-fabricated
concrete products by making optimum use of the advantages of both these methods in the same project. Although
the advantages of this building method is well recognised throughout the world and a feasibility study illustrated
that HCC is a suitable building method in South Africa, it remains under-utilised in the country.
HCC encourages early involvement from the project team and provides clients with the best value projects and a
"win-win" situation for the project team during the project development. The objective of this study is to identify
barriers that prohibit an increased utilisation of HCC for the South African construction industry. Additionally, it
provides possible solutions to overcome these barriers. These proposed solutions are similar to the programmes
and methods that are implemented in other countries to improve their HCC utilisation. Furthermore, drivers are
identified in this study to implement these solutions in the industry and a proposed "change model" is developed
for private companies to assist with the change process.
This study is unique because current South African conditions are used to establish the barriers and solutions.
Furthermore, it takes into account that not all countries have such progressive construction industries as the
European markets and therefore it considers solutions and drivers that are suitable for less advanced industries
such as South Africa. The model that is proposed is applicable to any industry regardless of its nature or country.
Although the United Kingdom is not the widest user of pre-fabricated concrete products, their HCC research is
extensive, making it a suitable comparative country for the South African construction industry.
During the investigation, the procurement methods in South Africa were found to be traditional and do not
allow for early involvement or partnering in the project team. To obtain early involvement, it is critical to initiate
methods such as design-and-build, contract management or public-private-partnerships during the procurement
phase.
Decision and design assistance from the whole project team and software tools are essential when HCC is
considered. Because the South African construction industry does not provide such support it is advised here
to incorporate contractors from an early stage and to develop software tools that can assist during the decision
making and design process of HCC structures. The industry does not provide the project team with sufficient
training programmes that increase knowledge of HCC. Training programmes that are cognitive stimulating
must be developed for the industry. Furthermore, a database is required to illustrate the utilisation of different
pre-fabricated products and in different projects within South Africa. Labour-intensive construction regulations and green building techniques (not compulsory) are promoted in South
Africa. Labour-intensive programmes should consider the negative impact it has on the labourers and consider
HCC as a building technique because the pre-fabricated elements are manufactured in a controlled and safe
environment. It is advised that the toolkits that are used for green building accreditation, must be revised to
accommodate the additional benefits such as less waste generation, that HCC offers to a project.
Regardless of the country in which HCC is utilised, the environment must be acceptable for the innovation. By
analysing the criteria that influences the use of HCC in a country and adding weighting functions to these criteria,
the acceptability towards the innovation can be obtained.
Furthermore, public clients and companies are recognised here as drivers of change. While public clients can commit
to HCC for the cost, labour-intensive factories, green building methods, improved health and safety, training for
labourers, private companies can utilise HCC to provide best value to a project. A model is proposed here for
innovative companies that will allow them to change not only the company, but the industry towards a HCC
"mindset". / AFRIKAANSE OPSOMMING: Hibriede beton konstruksie (HBK) is ’n tegniek waarby beide voorafvervaardigde betonelemente en in-situ beton
in dieselfde projek gebruik word ten einde voordeel uit beide metodes te trek. Alhoewel die voordele van die
konstruksietegniek wel bekend is in talle lande van die wêreld en ’n uitvoerbaarheidsanalise getoon het dat HBK ’n
voordelige konstruksiemetode vir Suid-Afrika is, is dit tans onderbenut in die plaaslike sektor.
HBK bied vir kliënte projekte van goeie waarde en omdat dit vroeë betrokkenheid verg vanaf die projekspan,
resulteer dit ’n "wen-wen" situasie tydens die projekontwikkeling. Die doel van hierdie studie is om die hindernisse
te ondersoek wat veroorsaak dat HBK nie meer gereeld in Suid-Afrika gebruik word nie. Ten einde die effekte
hiervan te verminder, word moontlike oplossings vir hierdie hindernisse voorgestel. Die oplossings is gebaseer op
tegnieke en metodes wat geïmplimenteer word in ander lande waar HBK gebruik word. Rolspelers wat hierdie
verandering na HBK kan dryf word geïdentifiseer en ’n model om verandering binne ’n maatskappy te lei word
voorgestel om die rolspelers te ondersteun tydens die proses.
Hierdie studie is uniek omdat dit inligting gebruik van die huidige situasie van die Suid-Afrikaanse
konstruksie-industrie om die hindernisse en oplossings te identifiseer. Omdat nie alle konstruksie-industrieë
so vooruitstrewend is soos in Europese lande nie, is die oplossings en rolspelers relevant vir enige land wat ’n
industrie het wat soortgelyk is aan Suid-Afrika. Die model wat voorgestel word is ook relevant tot enige industrie
afgesien van die land waar nuwe tegnieke geïmplimenteer word.
Alhoewel dit bevind is dat die Verenigde Koningkryk nie die grootste gebruikers van HBK is nie, is hulle navorsing
in die veld omvattend. Daarom word die Verenigde Koningkryk beskou as ’n voorbeeld om Suid-Afrika se
konstruksie-industrie mee te vergelyk, asook om inligting van HBK te verkry.
Tydens die studie is bevind dat die projekaanstellingsmetodes van projekte in Suid-Afrika tradisioneel is, aangesien
dit nie toelaat vir vroeë betrokkenheid of vennootskappe binne die projekspan nie. Om vroeë betrokkenheid te
verkry, is dit noodsaaklik om van ontwerp-en-bou, kontrakbestuur of publiek-privaat-vernootskappe gebruik te maak.
Tans is daar geen hulp wat aan ontwerpers verleen word ten opsigte van besluitnemingsmodelle en ontwerpsagteware
wanneer HBK oorweeg word in Suid-Afrika nie. Die behoefte aan sulke bystand dui daarop dat sagtewarepakkette
ontwerp moet word wat toepaslik is vir Suid-Afrika se konstruksie-industrie. Die industrie bied nie doelgerigte en
genoegsame opleidingsprogramme aan om die industrie se kennis van HBK te verbreed nie. Addisionele opleiding
wat kognitiewe stimulasie sal bied vir die hele projekspan word aanbeveel. ’n Databasis wat HBK projekte insluit,
moet geskep word om die industrie bloot te stel aan die verskillende moonlikhede. Arbeid-intensiewe konstruksie-regulasies asook groen konstruksietegnieke (nie wetgedrewe nie) word sterk bevorder
in Suid-Afrika. Dit word hier aanbeveel, dat voorafvervaardiging se addisionele voordele in ag geneem word wanneer
hierdie regulasies en tegnieke relevant is. Hierdie voordele sluit onder meer in: die veiligheid wat aan werkers
gebied word in arbeid-intensiewe fabrieke en die vermindering van afval in HBK projekte.
Afgesien van die land waarin HBK gebruik word, moet die omgewing ontvanklik vir die tegniek wees. Deur
verskillende kriteria te analiseer wat die gebruik van HBK beïnvloed binne ’n land en geweegde faktore daaraan te
koppel, kan die ontvanklikheid van die innovasie bepaal word.
Laastens word publieke kliënte en maatskappye as die drywers (of katalisators) wat verandering kan meebring,
beskou. HKB bied onder andere die volgende voordele aan publieke kliënte: koste-effektiwiteit, arbeid-intensiewe
werk, groen konstruksie, beter gesondheid, veiligheid en opleiding vir werkers. Maatskappye kan gebruik maak van
HBK om waarde tot hul projekte toe te voeg. ’n Model word hier voorgestel om innoverende maatskappye in staat
te stel om nie net hulself nie, maar ook die industrie as ’n geheel te help om ’n gesindheidsverandering jeens HBK
te skep.
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Assessment of the behaviour factor for the seismic design of reinforced concrete structural walls according to SANS 10160 : part 4Spathelf, Christian Alexander 12 1900 (has links)
Thesis (MScEng (Civil Engineering))--Stellenbosch University, 2008. / The South African code for the design loading of building structures, namely SABS
0160 (1989), was revised with the requirements for seismic design prescribed in SANS
10160: Part 4: Seismic actions and general requirements for buildings. SANS 10160:
Part 4 incorporates the seismic design provisions of several seismic codes of practice,
however, the influence of the value prescribed for the behaviour factor has not been
established with regard to South African conditions.
The behaviour factor is used by most seismic design codes to account for the energy
dissipating effects of plastification in structural systems when subjected to earthquake
ground motion, to reduce the elastically determined forces to be designed for. However,
a considerable difference is observed in the values of the behaviour factor prescribed for
the design of reinforced concrete walls between the leading international seismic codes.
The aim of this study is to assess the value of the behaviour factor prescribed in SANS
10160: Part 4 for reinforced concrete structural walls under the influence of South
African seismic conditions and code requirements.
A method of quantifying the value of the behaviour factor was developed and
implemented in the study by Ceccotti (2008). This method entails estimation of the
maximum analytical behaviour factor as the ratio of seismic intensity at failure of the
structure to the seismic intensity prescribed by the design code. Such a method is
adopted for this study where the lateral force resisting systems of six-, eight- and tenstorey
buildings are investigated with nonlinear static analysis to quantify the maximum
computationally-determined value of the behaviour factor.
Firstly, it is observed that it is possible to quantify the value of the behaviour factor
through the use of a computational study. The nonlinear static method of analysis is
shown to provide reliable results in the estimation of the behaviour factor for a sixstorey
building, however, does not perform well for taller buildings. Further investigation with the use of dynamic time-history analysis is proposed to evaluate the
influence of the factors identified in this study.
The behaviour of structural walls, designed for reduced forces with the prescribed
behaviour factor of 5.0, exhibits high yield strengths and resists the design seismic
action entirely elastically. This high strength is found to be due to the
reliability/redundancy factor prescribed by SANS 10160: Part 4 and because of the high
values of structural overstrength. Similar studies observed high values of structural
overstrength for buildings designed for low seismic intensity, which were shown to
result from the fact that the resistance required to gravity loading became more critical
than the seismic loads in the design of the structural system.
This study identifies several factors that influence the value of the behaviour factor,
such as the number of walls in the lateral force resisting system; the number of storeys
of the buildings; available displacement ductility of the structural system; and the
ground type designed for.
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Deflections of reinforced concrete flat slabsEigelaar, Estee M. 03 1900 (has links)
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2010. / ENGLISH SUMMARY: It is found that the serviceability limit state often governs the design of slender reinforced concrete
members. Slender flexural members often have a percentage tension reinforcement less than 1.0%
and an applied bending moment just above the point of first cracking. For such members, the
available methods to evaluate the serviceability conditions produce inadequate and unrealistic
results. The evaluation of the serviceability of a slender member includes the calculation of the
predicted deflection, either by empirical hand-calculation or analysing a finite element model, and
the verification using the span-to-effective-depth ratio.
The focus of the study is on flat slab structures. It investigates the different deflection prediction
methods and the span-to-effective-depth ratio verifications from various design standards. These
design standards include the ACI 318 (2002), the SABS 0100-1 (2000), the EC2 (2004) and the BS
8110 (1997). The background to the methods, as well as the parameters which influences the
deflection development for lightly reinforced members, are investigated in order to define the
limitations of the methods. As a result of the investigation of the deflection calculation methods, an
Alternative Approach is suggested and included in the comparisons of the various methods.
The deflection prediction methods and the span/effective depth verification procedures are
accurately formulated to predict the serviceability behaviour of beams. Additional approaches had
to be used to apply these methods to a two-dimensional plane such as that of a flat slab structure.
The different deflection prediction methods and the span/effective depth verification methods are
calculated and compared to the recorded data of seven experimental flat slab specimens as
performed by others. A study by Gilbert and Guo (2005) accurately recorded the flexural behaviour
of flat slab specimens under uniformly distributed loads for test periods up to 750 days. The
methods to evaluate the serviceability of a slender member were also applied to slab examples
designed using South African standards.
The study concludes by suggesting a suitable deflection prediction method for different parameter
(limitation) categories with which a slender member can comply to. The typical span/effective depth
ratio trend is also presented as the percentage tension reinforcement for a slender member changes. It is observed that the empirical hand-calculation methods present more reliable results
than those of the finite element models. The empirical hand-calculation methods are accurate
depending on the precision to which the slab was constructed relative to the actual slab design.
The comparison of the deflection methods with South African case studies identified the role played
by construction procedures, material parameters and loading history on slab behaviour. / AFRIKAANSE OPSOMMING: Die diensbaarheidstoestand is in baie gevalle die bepalende faktor vir die ontwerp van slank
gewapende beton elemente bepaal. Slank elemente, soos lig bewapende buigbare beton elemente,
het gewoonlik ‘n persentasie trekbewapening van minder as 1.0% en ‘n aangewende buigmoment
net wat net groter is as die punt waar kraking voorkom. Die metodes beskikbaar om die
diensbaarheid van sulke elemente te evalueer gee onvoldoende en onrealistiese resultate. Die
evaluering van die elemente in die diensbaarheidstoestand sluit in die bepaling van defleksies deur
berekening of die analise van ‘n eindige element model, en die gebruik van die span/effektiewe
diepte metode.
Die fokus van die studie is platbladstrukture. Die doel van die studie is om die verskillende metodes
vir die bereking van defleksie asook die verifikasie volgens span/effektiewe diepte metodes van die
verskillende ontwerp standaarde te ondersoek. Die ontwerp standaarde sluit die ACI 318 (2002),
SABS 0100-1 (2000), EC2 (2004) en die BS 8110 (1997) in. Die agtergrond van hierdie metodes is
ondersoek asook die parameters wat ‘n rol speel, sodat die beperkings van die metodes
geidentifiseer kan word. As ‘n gevolg van die ondersoek na die beperkings van die metodes, is ‘n
Alternatiewe Benadering voorgestel. Die Alternatiewe Benadering is saam met die metodes van die
ontwerpstandaarde gebruik om die verskille tussen die metodes te evalueer.
Die defleksievoorspelling en die span/effektiewe diepte verifikasie metodes is korrek geformuleer
om die diensbaarheid van balke te evalueer. Ander benaderings was nodig om die diensbaarheid van
blad blaaie te toets.
Die onderskeie defleksievoorspelling en span/effektiewe diepte metodes is bereken vir sewe
eksperimentele plat blaaie soos uitgevoer deur ander navorsers. Gilbert and Guo (2005) het ‘n studie
uitgevoer waar die buigingsgedrag van die sewe plat blaaie, met ‘n uniforme verspreide las vir ‘n
toetsperiode van tot 750 dae, akkuraat genoteer is. Die metodes om die diensbaarheid van ‘n slank
element te toets, was ook op Suid-Afrikaanse blad voorbeelde getoets. Dit was gedoen om die Suid-
Afrikaanse ontwerp van ligte bewapende beton elemente te evalueer. Die gevolgetrekkings stel ‘n gepaste defleksie metode vir ‘n slank element vir verskillende beperking
kategorië voor. Dit is ook verduidelik hoe die tipiese span/effektiewe diepte verhouding met die
persentasie trek bewapening vir ‘n slank element verander. Dit is bevind dat die imperiese
handmetodes om defleksies te bereken, meer betroubaar as die eindige element modelle se
resultate is. Die imperiese handberekening metodes is akkuraat relatief tot hoe akkuraat die blad
konstruksie tot die blad ontwerp voltooi is.
‘n Vergelyking van defleksieberekening met Suid-Afrikaanse gevallestudies het die belangrikheid van
konstruksieprosedures, materiallparamteres and belastingsgeskiedenis geïdentifiseer.
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The effect of seismic activity on reinforced concrete frame structures with infill masonry panelsJarvis, Wesley James 04 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Certain regions within the Western Cape Province are at risk of a moderate intensity
earthquake. It is therefore crucial that infrastructure in these areas be
designed to resist its devastating effect. Numerous types of structural buildings
exist in these seismic prone areas. The most common types are either reinforced
concrete framed buildings with masonry infill or unreinforced masonry
buildings. Many of these buildings predate the existence of the first loading
code of 1989 which provided regulations for seismic design. The previous code
was superseded in 2010 with a code dedicated to providing guidelines for seismic
design of infrastructure. A concern was raised whether these buildings
meet the requirements of the new code. A numerical investigation was performed
on a representative reinforced concrete framed building with masonry
infill to determine whether the building meets the new code’s requirements.
The results from the investigation show that the stresses at critical points in
the columns exceed the codified requirements, thus leading to local failure.
After careful review it was discovered that these local failures in the columns
will most likely lead to global failure of the building. / AFRIKAANSE OPSOMMING: In sekere streke in die Wes-Kaap bestaan daar risiko van matige intensiteit
aardbewings. Dit is dus noodsaaklik dat die infrastruktuur in hierdie gebiede
ontwerp word om die vernietigende uitwerking te weerstaan. Gebous
met verskillende tipes strukturele uitlegte kom in hierdie gebied voor. Die
mees algemene struktuur tipe is gewapende beton-raam geboue met baksteen
invol panele sowel as ongewapende baksteen geboue. Baie van hierdie geboue
is gebou voor die eerste las-kode van 1989 wat regulasies vir seismiese ontwerp
voorsien in gebruik geneem is. Die vorige kode is vervang in 2010 met ’n
kode toegewy tot die verskaffing van riglyne vir seismiese ontwerp van infrastruktuur.
Kommer het ontstaan of hierdie geboue voldoen aan die vereistes
van die nuwe kode. ’n Numeriese ondersoek is uitgevoer op ’n verteenwoordigende
gewapende beton geraamde gebou met baksteen panele om te bepaal
of die gebou voldoen aan die nuwe kode vereistes rakende sismiese ontwerp.
Die resultate van die ondersoek toon dat die spanning op kritieke punte in
die kolomme die gekodifiseerde vereistes oorskry, wat tot plaaslike faling lei.
Na verdere onderssoek is dit bepaal dat die plaaslike faling in die kolomme
waarskynlik tot globale faling van die gebou sal lei.
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Evaluation of Chloride Threshold for Steel Fiber Reinforced Concrete Composited in Aggressively Corrosive EnvironmentsUnknown Date (has links)
Highway drainage pipes utilize concrete reinforced with steel wire to help mitigate water,
earth, and traffic loads. Drainage pipes reinforced with zinc electroplated steel fibers
offer a lower steel alternative to traditional steel wire cage reinforcements. The objective
of the thesis research was to determine the physical and electrochemical characteristics of
zinc electroplated steel fiber corrosion propagation. Experimental programs include:
Fracture analysis of zinc electroplated steel fibers embedded in dry-cast concrete pipes
exposed to varying chloride concentrations; Visual analysis of zinc electroplated steel
fibers embedded in concrete exposed to varying chloride concentrations; Electrochemical
analysis of zinc electroplated steel fibers embedded in concrete exposed to varying
chlorides; Chloride threshold determination for zinc electroplated steel fibers immersed
in simulated pore solution. Between the four experimental programs the most significant
conclusion is that oxygen, moisture, and chlorides past the chloride threshold must be
present for corrosion to propagate significantly on the zinc electroplated steel fibers. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
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Concrete diffusivity and its correlation with chloride deposition rate on concrete exposed to marine environmentsUnknown Date (has links)
The aim of this study was to investigate the diffusion of chloride ions into concrete samples that were exposed in scenarios that simulate the splash, tidal, atmospheric, and immersed portions of a marine structure. To study the atmospheric deposition, the project also investigated the relationship between chloride ion deposition on the wet candle and its accumulation into concrete samples. Results from the wet candle experiment indicated that between 2% and 45% of the chlorides deposited per square meter of exposed area could be found within the concrete samples. After 6 months, slag G1a blocks showed the most resistance to chloride penetration in the tidal and splash simulations. After 10 months of exposure, fly ash samples had the slowest rates of diffusion in the tidal simulation while the fly ash + silica fume samples and the slag samples measured similar rates of diffusion within the tidal zone. After 90 days of curing, cylinders composed of 20% fly ash & 8% silica fume measured the highest average resistivity values and were found to be less vulnerable to chloride ion penetration than the 20% fly ash and the 50% slag concrete through rapid migration tests. / by Victor Anthony Echevarria. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Experimental evaluation of the durability of fly ash-based geopolymer concrete in the marine environmentUnknown Date (has links)
The construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in the way of producing concrete. However, to seriously consider geopolymer binders as an alternative to ordinary Portland cement, the durability of this new material should be evaluated in any comparative analysis. The main purpose of this study was to evaluate the durability characteristics of low calcium fly ash-based geopolymer concretes subjected to the marine environment, compared to ordinary Portland cement concrete with similar exposure. To achieve this goal, 8 molar geopolymer, 14 molar geopolymer and ordinary Portland cement concrete mixes were prepared and tested for exposure in seawater. Compressive strengths in the range of 2900 to 8700 psi (20-60 MPa) were obtained. The corrosion resistance performance of steel-reinforced concrete beams, made of these mixes, was also studied, using an accelerated electrochemical method, with submergence in salt water. The test results indicated that the geopolymer concrete showed excellent resistance to chloride attack, with longer time to corrosion cracking, compared to ordinary Portland cement concrete. / by Jean-Baptiste Edouard. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Structural engineering aspects of prestressed concrete reactor vessels.Goldman, Bruce Ira January 1975 (has links)
Thesis. 1975. M.S.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / Bibliography: leaves 124-129. / M.S.
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Correlation of Chloride Diffusivity and Electrical Resistance for Cracked ConcreteUnknown Date (has links)
The durability of Reinforced Concrete (RC) structures in the Marine environment is
causing serious concern in the structural infrastructure. Reinforced concrete structures,
exposed to aggressive environments, are expected to last with little or no maintenance for
long periods of time. However, one of the most serious environmental exposures that
causes degradation is Chloride Diffusion, due to shrinkage, atmospheric corrosion, and
tide-induced wet and dry conditions at the air-water interfaces of coastal structures.
Therefore, chloride diffusivity, which correlates with the electrical resistivity, has a
significant impact on the durability of concrete. Concrete chloride diffusivity has been
experimented by multiple agencies and researchers on sound concrete, but there is a
considerable need for investigation of the durability of cracked concrete in the marine
environment. The two test methods carried out are presented: Standardized American Society for Testing
and Materials (ASTM) C1202 for Rapid Chloride Permeability (RCP) and ASTM D257
for Surface Resistivity (SR), and Nordtest (NT) Build 492 for Rapid Chloride Migration
(RCM) and Bulk Resistivity (BR) for both sound (uncracked) and cracked (micro and
macro) concrete. The limitations of the ASTM method, due to measurements before the
steady-state migration is reached, does not account for leakage in cracked concrete, and the
heating of the specimen due to higher current that increase the conductivity are indicated.
The Rapid Chloride Migration test provides for the non-steady state of diffusion. Again,
Bulk Resistivity, in contradistinction to Surface Resistivity is more accurate for cracked
concrete. The correlation betweeen RCM-BR are plotted. Chloride Permeability/Migration
is an important parameter that governs the Durability of Concrete.
The principal contribution is the highlighting of the inadequacy of the current widely used
standard ASTM C1202 for diffusivity testing, and the need for revision with further
investigation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
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Behavior of Non-Ductile Slender Reinforced Concrete Columns Retrofit by CFRP Under Cyclic LoadingAules, Wisam Amer 14 March 2019 (has links)
In the Middle East region and many countries in the world, older reinforced concrete (RC) columns are deemed to be weak in seismic resistance because of their low amount of reinforcement, low grades of concrete, and large spacing between the transverse reinforcement. The capacity of older RC columns that are also slender is further reduced due to the secondary moments. Appropriate retrofit techniques can improve the capacity and behavior of concrete members. In this study, externally bonded Carbon Fiber Reinforced Polymer (CFRP) retrofit technique was implemented to improve the behavior of RC columns tested under constant axial load and cyclic lateral load. The study included physical testing of five half-scale slender RC columns, with shear span to depth ratio of 7. Three specimens represented columns in a 2-story, and two specimens represented columns in a 4-story building. All specimens had identical cross sections, reinforcement detail, and concrete strength. Two specimens were control, two specimens were retrofit with CFRP in the lateral direction, and one specimen retrofit in the longitudinal and lateral directions. A computer model was created to predict the lateral load-displacement relations. The experimental results show improvement in the retrofit specimens in strength, ductility, and energy dissipation. The effect of retrofitting technique applied to two full-scale prototype RC buildings, a 2-story and a 4-story building located in two cities in Iraq, Baghdad, and Erbil, was determined using SAP2000.
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