Árbók VFÍ/TFÍ - 01.06.2006, Qupperneq 245

ÞREYTUÁRAUN Á STÁLBRÝR
Jóhannes Loftsson lauk fyrrihlutanámi í efnaverkfræði frá H( 1995 og meistaraprófi í efnaverkfræði frá DTU í Dan-
mörku 1999.Hann starfaði hjá Isaga 1999,var verkefnisstjóri hjá Iðntæknistofnun 1999-2000, en hefur unnið á Verk-
fræðistofu SigurðarThoroddsen frá 2000. Árið 2006 útskrifaðist hann með meistarapróf í byggingarverkfræði frá H(.
Baldvin Einarsson lauk prófi í byggingarverkfræði frá H( 1974, meistaraprófi frá Imperial College i London 1976 og
doktorsprófi frá sama skóla 1983. Hann starfaði sem verkfræðingur hjá Vegagerðinni 1974-1975 og 1981-1997 og
síðan á verkfræðistofunni Línuhönnun frá 1997, nú sem sviðsstjóri vega- og byggðasviðs. Hann hefur verið stunda-
kennari við verkfræðideild H[ síðan 1982 og einnig prófdómari viðTHl.
Bjarni Bessason lauk prófi í byggingarverkfræði frá H( 1981, meistaraprófi frá DTH í Danmörku 1983 og doktorsprófi frá
NTH (Noregi 1992. Hann starfaði hjá Verkfræðistofnun H( 1983-1988 og hjá Norges Geotekniske Institutt (NGI) í Osló
1992-1995. Bjarni varð dósent við verkfræðideild HÍ árið 1995 og hefur verið prófessor frá 2002.
Abstract
Fatigue resistance is an important aspect in steel bridge design. Since lceland has historically had low traffic, fatigue resis-
tance has been given minimal consideration. However, as the population of Reykjavik metropolitan area has been steadi-
ly growing in recent years, the amount of traffic has been greatly increasing.Therefore, the consideration of fatigue resis-
tance has now become more relevant.
This project investigated fatigue resistance by designing a composite box girder bridge for the proposed Sundabraut main
road.This bridge would be located centrally in the Reykjavik metropolitan area and would be expected to carry heavy traf-
fic, making it susceptible to fatigue damage.
In fatigue analysis all critical details, such as welds or connections, which are susceptible to fatigue damage, are especially
analyzed.These critical details fall into different fatigue classes, which decide their fatigue resistance. In this project the
work was limited to analyzing one such critical detail.
The fatigue load was calculated from all five fatigue load models prescribed in the Eurocode standards. Special emphasis
was put on the fifth load model, which is the most precise model and incorporates the use of real traffic measurements.
Calculations were mainly based on data that was gathered from a Weight in Motion (WIM) traffic classifier.This WIM is the
most advanced traffic monitor that the lcelandic Road Administration is currently running. It is located at Esjumelar, in the
outskirts of Reykjavik metropolitan area and collects detailed traffic information induding axle load and vehicle classifica-
tion.
The calculations gave analogous results for all the fatigue models, thus indicating that traffic load on lcelandic roads is sim-
ilar to traffic load on other European roads. Furthermore, analysis of the Sundabraut bridge revealed that if the critical
detail being investigated would be of the least fatigue resistant detail dass; it could only be expected to last 23 years,
assuming an average traffic load of 40.000 cars per day. However, by using a slightly more fatigue resistant detail, these
fatigue problems could be easily avoided.