Meet­ing chal­lenges through in­no­va­tions, the Maha Metro way

Maha Metro aims at con­struct­ing 38.215 km long track along 38 sta­tions and con­nect­ing four cor­ners of the city of nag­pur. But ex­e­cut­ing the project work was eas­ier said than done. Maha Metro had to face a num­ber of chal­lenges while do­ing so.

Realty Plus - - Contents -

while chal­lenges were uni­ver­sal across city, ex­e­cut­ing the project work on Cen­tral Av­enue – a crowded road with com­mer­cial spots on ei­ther side – turned out to be Or­ga­ni­za­tion’s tough­est task. The work in this stretch, which is part of Reach-iv in Metro par­lance, starts near Rail­way Sta­tion and ends at Pra­jap­ati Na­gar.

Cen­tral Av­enue is one of most crowded roads of the city with com­mer­cial spots lined on ei­ther sides for al­most the en­tire stretch. So while ex­e­cut­ing project Maha Metro Nag­pur had to en­sure that not only traf­fic there re­mained undis­turbed, but also the speed of work re­mains same. The grav­ity of traf­fic con­ges­tion on Cen­tral Av­enue can be gauged from the fact that as many as 45,000 ve­hi­cles pass through this 17 km long road ev­ery day. It has 17 traf­fic junc­tions and is one of the old­est part of city with his­toric struc­tures lined up on its ei­ther sides. Some ma­jor in­no­va­tions and their ef­fec­tive use by Maha Metro were:

• Psc can­tilever pier arms and t-gird­ers

As, reach 4 sta­tions are to be built over the busy Cen­tral Av­enue, pre-stressed pier arms with 10m can­tilever and pre­cast T-gird­ers ad­join­ing each other have been de­signed to sup­port 22m wide and 77.50m long main sta­tion box struc­tures in­stead of con­ven­tional cast-in-situ struc­ture. The Pre-stressed pier arms have been de­signed with 2 stage stress­ing to have op­ti­mum de­sign ben­e­fits and pre­cast T-gird­ers ar­range­ment, which elim­i­nates ne­ces­sity of any ground sup­ports, which in turn re­sulted safe and faster con­struc­tion over the busy road un­der­neath. Also, the T-gird­ers are de­signed with­out any bear­ings, so that main­te­nance has­sles could be evaded.

• Unique seg­ment de­sign and erec­tion at agarsen­square

Dur­ing the course of de­sign, we come across the chal­lenge of con­struct­ing 43m span at Agrasen square and our de­sign team was up for the chal­lenge. Ac­cord­ingly Piers were de­signed with ex­tended pier caps of 3 m can­tilever on ei­ther side. With this de­sign we could elim­i­nate spe­cial type su­per struc­ture and man­aged to com­plete with 37m stan­dard box type viaduct struc­ture with­out dis­turb­ing traf­fic and statue un­der­neath. Sub­se­quently, we had to over­come an­other con­struc­tion chal­lenge of lift­ing seg­ments as lift­ing point of launch­ing girder was ex­actly over the statue of Agrasen Ma­haraj lo­cated at the cen­tre of round about and ne­ces­si­tat­ing re­lo­ca­tion of statue. But, shift­ing of the statue is a com­plex is­sue and thus it was de­cided to use macal­loy bars with­out dis­turb­ing the statue, sav­ing a lot of time and cost.

Maha Metro or Ma­ha­rash­tra Metro Rail Cor­po­ra­tion Lim­ited launched its Nag­pur project as a se­ri­ous ef­fort aimed at end­ing trans­porta­tion re­lated woes of Nag­pur – the se­cond cap­i­tal of Ma­ha­rash­tra which has a bustling pop­u­la­tion of close to 3.5 mil­lion.

• Por­tal Pier de­sign to avoid Util­ity di­ver­sion at Pra­jap­ati

As NHAI fly­over and sub­way are be­ing con­structed at Pra­jap­ati sec­tion, metro align­ment needs to be de­signed ad­ja­cent to NHAI fly­over within 24m strip. Also, Metro viaduct at Pra­jap­ati sec­tion is in­te­grated with NHAI road fly­over ex­clud­ing Pra­jap­ati sta­tion and few tran­si­tion spans. How­ever, dur­ing util­ity ex­plo­ration at Pra­jap­ati sta­tion lo­ca­tion, we found that many wa­ter pipe­lines in­clud­ing pres­sure pipe sup­ply­ing wa­ter to power plant and bunch of drink­ing wa­ter pipe lines were lo­cated ex­actly be­low metro align­ment. Since most of the pipe­lines are main wa­ter lines, it is very dif­fi­cult to get the di­ver­sion ap­provals from the au­thor­i­ties or the shut­down per­mis­sions as it in­volves many reg­u­la­tions and lengthy process. There­fore, Pra­jap­ati sta­tion was de­signed with Por­tal piers ar­range­ment, which in turn proved to be ideal de­sign as Pra­jap­ati sta­tion is in­te­grated with Prop­erty de­vel­op­ment and even­tu­ally four lev­els could be ac­com­mo­dated, which in turn jus­ti­fies the cost in­curred on por­tal pier con­struc­tion. Pra­jap­ati sta­tion be­ing an only metro sta­tion with 4 lev­els, in­clud­ing 2 PD lev­els stands out from all the rest.

• se­cond largest Bal­anced can­tilever Bridge to be in­stalled

Though this is not part of Cen­tral Av­enue, ex­e­cut­ing this part of project was equally tough. Viaduct had to be in­stalled above rail line near Anand Talkies in Sitab­uldi area of Reach-iv. A 231 me­ter long Bal­anced Can­tilever Bridge was pro­posed to be in­stalled above Rail­way Track near Anand Talkies, Sitab­uldi of Reach-iv. Metro team de­cided to use Bal­anced Can­tilever Bridge there. But even launch­ing of Bal­anced Can­tilever Bridge is a chal­leng­ing task as the lo­ca­tion where the bridge is sup­posed to be erected has class “A” traf­fic (high den­sity) and a live rail­way traf­fic. Also height of Piers as high as 16 me­ters due to ge­o­graph­i­cal pro­file is also a chal­lenge in it­self. Also, the lo­ca­tion – Anand Talkies, Sitab­uldi is a high pop­u­la­tion den­sity zone. The pro­posed Can­tilever is a 3 span bridge with span­ning con­fig­u­ra­tion of 56.2m + 103m + 72m, 103m span across rail­way track. It is se­cond largest span by Bal­anced Can­tilever method across the rail­way lines in In­dia.

By: Ma­ha­rash­tra Metro Rail Cor­po­ra­tion Lim­ited

Newspapers in English

Newspapers from India

© PressReader. All rights reserved.