HPL
has the expertise of pre casting bridge
spans in its factory and transporting these
for erection at site. In certain contracts
with the Indian Railways, HPL had to widen
existing bridges by jacketting the old piers,
removing the old spans and erecting new
prestressed concrete spans to accommodate
higher bridge load. This process is needed
when the old bridges show conditions of
distress or when the load carrying capacity
of the entire route is to be upgraded. Since
the bulk of activities were carried out
in the factory or in a precasting yard near
the work site, record construction times
were achieved by HPL. For the modernisation
of Delhi-Rewari line, the Northern Railways
wanted upgradation of load carrying capacity
of the bridges & also stipulated that
the work be carried out under traffic blocks.
Since traffic blocks are normally of the
duration of one to two weeks at the most,
the entire bridge super-structure was designed
and precast in the factory, steam cured
and transported to the bridge sites well
in advance. The final operation of dismantling
the old bridges and erecting the new spans
was carried out by mobile cranes during
the traffic blocks. Picture on the facing
page shows a bridge on the Delhi-Rewari
section of the Northern Railway built by
this technique. Incidentally, the time period
allowed was very short but was adhered to.
220 bridge spans were completed in just
six months.
After
the successful completion of 220 bridge
spans in a record time of 180 days, on the
Delhi-Rewari line of Northern Railway, HPL
has been entrusted with the execution of
many prestigious bridge projects by Indian
Railways. Notable among these are:
1) Strengthening
of piers & abutments of SABI Bridge
including the replacement of old steel girders
by prestressed concrete girders in connection
with conversion of Delhi-Jaipur Metre Gauge
into Broad Gauge.
2) Construction,
supplying, leading & erection of PRC
Slabs of Bridges in Jodhpur-Jaisalmer section
of Northern Railway.
3) Construction,
supplying, leading & erection of PRC
Slabs/RCC ballast retainers for bridge in
Phulera-Merta Road Jodhpur, in Hissar-Jodhpur
gauge conversion of Northern Railway.
4) Construction, supplying,
leading & erection of PRC/RCC slab of
Bridge in Delhi-Ambala section.
The art of efficient and fast working has
to be mastered to serve clients in the infrastructure
sector. Railway Bridges under traffic blocks
and road over-bridges built at night, when
the road traffic is low, are the forte of
HPL. The railway over pass at Shahdara,
Delhi was built under traffic blocks of
just six hours. The girders were manufactured
under factory conditions and erected at
the site with the cranes.
