Examination of bonding between successive lifts of concretes having different thixotropy levels by surface scanning
Başlık:
Examination of bonding between successive lifts of concretes having different thixotropy levels by surface scanning
Yazar:
Ersöz, Hasan Yavuz, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
xii, 144 leaves: color illustrarions, charts;+ 1 computer laser optical disc.
Özet:
Unexpected delays in casting can result in strength losses and should be examined considering the thixotropy of the concrete. The effects of thixotropy and delays in casting (0, 45, and 90 min) on concrete bonding strength and on the surface properties were examined. Firstly, 15 self-consolidating concretes (SCC) having different compositions with three different water/cement ratios (0.36, 0.41 and 0.46) three different fine/all aggregate ratios (0.45, 0.50 and 0.55) and two slump flow diameters (60 cm and 70 cm) were produced. Slump flow, visual stability index, T50, V-funnel, static sieve segregation, rheology, and thixotropy tests were carried out on fresh concrete. Considering the results obtained so far, three mixtures were selected to have high, low, and moderate thixotropy for subsequent tests on hardened concrete specimens. Five different roughening patterns were applied on the concrete specimens' interlayer zones by using wooden frames. Slant shear, bi-surface shear, and pull-off tests were conducted on the cylindrical, cubic and drilled specimens to assess bond strength, respectively. Slant shear test gave the highest bonding test results. The lowest results were obtained for the pull-off test. Lateral surfaces of the specimens were scanned with two different lenses. 2D and 3D scanning procedures were adapted with those lenses. Pattern and thixotropy effect was investigated. Lowest void area was obtained for high thixotropy. Highest compressive strengths were obtained for mid thixotropy and high thixotropy for slant shear and pull-off tests respectively. Image J and Matlab were used to the analyze images of the surfaces. Ultrasonic pulse velocity test was conducted on all specimens, moderate thixotropy gave the highest results for Ultrasonic Pulse Velocity test.
Yazar Ek Girişi:
Tüzel Kişi Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Master)--İzmir Institute of Technology: Civil Engineering.
İzmir Institute of Technology: Civil Engineering--Thesis (Master).
Elektronik Erişim:
Access to Electronic Versiyon.