Jägala joa jalakäijate silla tehniline projekt

Käesolevas lõputöös projekteeriti puidust jalakäijate sild Jägala joale. Lõputöös teostati arvutused konstruktsioonielementide ristlõigete leidmiseks. Dimensioonimisele kuulusid kõik puidust tarindid ning lisaks arvutati ka terasest riputid ja tuulesidemed. Raudbetoonist tarindite ja sõlmede dimensioonimist lõputöös käsitletud ei ole. Silla peakandjaks valiti kaar ristlõikega 240×1200 mm ja tugevusklassiga GL32h. Kõik ülejäänud liimpuidust tarindid valiti tugevusklassiga GL28h. Kaare põiksidemed valiti ristlõikega 200×600 mm. Sillateki laudis valiti ristlõikega 32×95 mm ja tugevusklassiga C24, pikitalad 100×240 mm ja põiktalad sarnaselt kaare põiksidemetega 200×400 mm. Sillateki osa, mis jäi joa poolt vaadatuna paremale kaare ja maapinna vahele, arvutati lihtalana ning ristlõikeks valiti samuti 200×400 mm. Terasest riputite läbimõõduks valiti 42 mm ja tuulesidemete läbimõõduks 30 mm. Terase tugevusklassiks on S355J2. Lisaks arvutustele pöörati suurt tähelepanu vastupidavate sõlmlahenduste väljatöötamisele. Sõlmed projekteeriti selliselt, et ilmastikuolude kätte jäävad puitosad oleksid kaetud ja kaitstud. Samuti anti juhiseid silla kasutamiseks ja hoolduseks. Silla projekteerimisel kasutasid lõputöö koostajad ka liit- ja tehisreaalsust. Nimetatud tehnoloogiate katsetamisel ilmnes, et liitreaalsus väga palju projekteerimist ei toetanud. Küll aga oli lõputöö koostajatel silla arhitektuurse lahenduse välja töötamisel suuresti kasu tehisreaalsusest, mis loodi BIM-koopas. See võimaldas näha erinevate algselt koostatud 3D eskiiside puudusi ning aitas kaasa parima lahenduse välja töötamisel.

“Technical project of the pedestrian bridge of Jägala waterfall” The main goal of this thesis is designing a timber pedestrian bridge on Jägala waterfall. The thesis is also concerned with the opportunities of the use of augmented and artificial reality and their application in designing the bridge. The bridge has been designed at the request of Jõelähtme rural municipality. Based on the development plan of Jõelähtme rural municipality for 2014–2025, the rural municipality intends to develop the area around Jägala waterfall as a recreational area and enliven tourism. The bridge is also necessary for the locals because there is no opportunity to cross Jägala river in the immediate vicinity of the waterfall. The most important load-bearing structures of the bridge, with the exception of the foundations, are designed of timber, because timber suits this area better than other materials due to being natural and close to nature. The authors of the thesis also wish to show that it is possible to build a durable timber bridge with the right joints, means of protection and maintenance. Calculations were made in the thesis to determine the cross-sections of structural elements. All timber structures were dimensioned and in addition, the steel hangers and bracings. The thesis does not handle the dimensioning of the elements and joints of reinforced concrete. The main load-bearing structure of the bridge is an arc with the cross-section 240×1200 mm and strength class GL32h. All remaining laminated timber structures were selected with the strength class GL28h. The horizontal connectors of the arc were selected with the cross-section 200×400 mm. The boards of the deck were selected with the cross-section 32×95 mm and strength class C24, side members 100×240 mm and crossbeams 200×400 mm similarly to horizontal connectors of the arc. The part of the bridge deck between the arc and the ground on the right side as seen from the waterfall was calculated a simple beam and the cross-section of this was also 200×400 mm. The diameter of the steel hangers was 42 mm and the diameter of the bracings was 30 mm. The strength class of steel is S355J2. In addition to calculations, a lot of attention was paid on developing durable connections. Joints were designed so that wooden parts exposed to the weather are covered and protected. Instructions were also provided for using and maintaining the bridge. The authors of the thesis also used augmented and artificial reality when designing the bridge. Testing these technologies revealed that augmented reality did not support designing very much. However, this has a lot of potential in the future as technology develops, because it enables all parties of the project to give a better overview of the project than 2D drawings or even 3D models. The authors gained a lot from artificial reality created in a BIM cave in developing the architectural solution of the bridge. This enabled to see the defects of various initial 3D sketches and helped develop the best solution.