Feasibility Study on Highly Slender Circular Concrete Filled Tubes Under Axial Compression

Simple item page
dc.contributor.authorMysore Paramesh, Pragatien
dc.contributor.committeechairLeon, Roberto T.en
dc.contributor.committeememberKoutromanos, Ioannisen
dc.contributor.committeememberHebdon, Matthew H.en
dc.contributor.departmentCivil and Environmental Engineeringen
dc.date.accessioned2017-02-15T09:00:17Zen
dc.date.available2017-02-15T09:00:17Zen
dc.date.issued2017-02-14en
dc.description.abstractCircular Concrete Filled Tubes are gaining importance in the construction industry due to their advantages insofar as economy and structural efficiency. Due to the recent developments in concrete and steel technology, the usage of high strength materials in these concrete filled tubes is increasing. The governing American specification (AISC 360-16) classifies these composite members as compact, non-compact and slender sections. The allowed section slenderness (ratio of diameter to thickness ratio) in each classification is related to the material properties (ratio of Young's modulus to yield strength ratio). AISC 360-16 is applicable for steels up to 75 ksi and concretes up to 10 ksi. These limits are lower than current available materials and restricts the usage of highly slender sections. As the strength of these tubes is dependent on local buckling, tests on many combinations of high strength steel and concrete are needed to extend these material limits. This preliminary research work focuses on understanding the local buckling behavior of highly slender sections and the effect of concrete infill and its confinement. The research began by compiling a database that highlighted a gap on tests with highly slender sections and high strength materials. To address this issue, a pilot set of experimental tests were conducted on short circular concrete filled members. An analytical evaluation of these experimental results are performed using 3D finite element analysis models. The critical buckling load is determined using J2 deformation theory, which proves to give a good estimate when compared with the experimental results. The main objective of the work is to determine if a simplified test like the one used in this work could be used for the large experimental study that will be necessary to expend the material limits in AISC 360-16. The limited data developed in this study indicates that the test can provide satisfactory results with a few improvements and refinements.en
dc.description.abstractgeneralA concrete-filled tube consists of a large steel circular or rectangular tube filled with concrete. This configuration is widely used in the construction industry, primarily as columns in high-rise buildings. Concrete filled tubes make the best use of both its constituent materials. The strength of the concrete in compression is increased by the confining action of the exterior steel tube, while the relatively thin steel tube is prevented from buckling by the presence of the concrete. Thus, this combination of the two materials, known as composite construction, results in a stronger and more ductile structural member than either a steel only or a reinforced concrete one. The design of these members is currently governed by the American Institute of Steel Construction Manual and Specification known as AISC 360-16. The provisions therein contain specific limits on the strength of both the steel and concrete allowed, as well as on the slenderness (wall thickness to width or diameter) of the tubes permitted. Because stronger steel and concretes are coming into the market and more slender tubes are available, the provisions need updating. This thesis presents a first step in that direction by testing some very slender concrete filled tubes in pure compression. This thesis presents preliminary research work focused on understanding the local instability of thin walled steel tubes and its effect with a concrete infill. The research began by compiling a database of experimental tests on concrete filled tubes. This database highlighted a gap on test results for thin walled tube sections and high strength materials. To address this issue, a pilot set of experimental tests were conducted on short circular concrete filled members. An analytical evaluation of these experimental results was performed using 3D finite element analysis models. The test results and accompanying analyses indicate that simplified test like the one used in this work could be used for the large experimental study that will be necessary to expend the material limits in AISC 360-16. The limited data developed in this study indicates that the test can provide satisfactory results with a few improvements and refinements.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.othervt_gsexam:9562en
dc.identifier.urihttp://hdl.handle.net/10919/75045en
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectLocal bucklingen
dc.subjectslenderen
dc.subjectconcrete filled tubesen
dc.subjecthigh strengthen
dc.titleFeasibility Study on Highly Slender Circular Concrete Filled Tubes Under Axial Compressionen
dc.typeThesisen
thesis.degree.disciplineCivil Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Mysore_Paramesh_P_T_2017.pdf
Size:
4.28 MB
Format:
Adobe Portable Document Format
Download

Collections

Masters Theses