PSI - Issue 13

Vera Vujović / Procedia Structural Integrity 13 (2018) 1901 – 1907 Vera Vujovi ć / Structural Integrity Procedia 00 (2018) 000–000

1903

3

Table 1. Building materials

Concrete

non-reinforced (t)

Reinforced (t)

39860

24,018.08

Steel

grid,bearings, carriageway, fence etc. (t)

reinforcing steel (t)

2601,29

741,45

Steel (accessories)

Fastening (t)

pads plates for schakle of sleepers (t)

47,18

13,54

Wood (oak)

Sleepers 26x24x280 (m 3 )

protective beams 16 x 20x36000 (23 m 3 )

144

167

The surface of the steel structure on which the anticorrosion protection is necessary is 42015 m 2 . Based on the data from the Helios Color Manufacturer catalog, theoretical consumption has been calculated for 27 t of paint for three layers of corrosion protection. Theoretical consumption at a certain thickness of a dry film on a smooth surface is calculated from the following formulas:

(1)

B D A 

(2)

C D A 

where A

bulk dry matter (%)x10 thickness of dry film (µm)

B C D

thickness of dry film (µm) xdensity (kg/l)

theoretical consumption (m 2 /kg). The basic parameter for determining theoretical consumption is volume dry matter representing the volume of non-volatile components in the total amount of coating. It can be calculated theoretically or determined experimentally. The vapor-dry matter can be represented by the ratio of the thickness of the dry and wet film. The lifetime for the C4 class of corrosivity is more than 15 years and the thickness of the dry coating is> 250μm. Color losses are estimated depending on the application method: brush, roller 5-10%; application by airless 15-20%; Application by air gun 20-30%. Physical factors that lead to higher consumption of paint are: residues in hoods and application equipment; expiration date; insufficient training of persons who apply coatings; losses due to atmospheric conditions (indoor space with good ventilation 5%; open space without wind 5-10%; open space with wind> 20%). Including losses, it is estimated that actual consumption will be 27 x1.40 = 37.80 t colors. Losses can be significantly reduced by up to 30% (27 x1.10 = 29.70 t) by more stringent control of consumption by control, selection of appropriate equipment, providing optimum working conditions and quality training of the person applying the coatings. 2. Main design 2.1. Main bridge construction design The main design of the bridge "Mala Rijeka" was done in the Bureau of the Institute for the Designing of the Yugoslav Railway Union ZJŽ, 1970. The main designers were: Ljubomir Jevtovic, Milorad Lukovic, Milivoje Kovacevic, Milorad Marković. Static and numerous controls were carried out by Nenad Kokanovic. Static and seismic calculations of RC columns were done computatively and electronically in the Engineering Computing Center "Energoprojekt" in 1969. The wind effect W = 250 kg/m 2 is the most dominant occasional load for the static calculation of the steel grid (speed 30 m/s and the strength at the level of 197 kg/m 2 ). Based on the results of model tests carried out during the design phase at the Institute of Aeronautics - Institute of Mechanical Engineering in Belgrade, the risk of overtaking light vehicles due to strong winds was prevented by designing a protective fence of full light panels of 1,30 m height.