No_8_August_1969 — Page 27

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Pre- and post-tensioned units in Marakina grandstand

A VARIETY of forms of precast con- crete is embodied in the new grand- stand built for the Province of Rizal, Philippines, at its Marakina Valley Sports Centre.

For the wall panels, bleacher seats, mezzanine beams, tie beams, fascia panels, flooring and roofing units pre- tensioning is used, as each of these component types comprises a number of units with the same lengths, cross- sectional shapes and sizes. Pretension- ing offered the most economic and speedy method of fabrication.

In the 50ft. cantilevered roof girders and columns, where a higher prestress- ing force was required, post-tensioning is employed, while straightforward re- inforced precast concrete is used for the massive bleacher girders, stair slabs, mezzanine columns and railing panels.

PROVINCE OF RIZAL

PHILIPPINE PRESTRESSED CONCRETE CO. INC.

NICOLAS ALDANA

RUPERTO C. GAITE

owners

structural designers and contractors

district engineer

consulting architect

The grandstand seats 8,000 spec- frame of the building consists of

bleacher girder, column and founda- tion tie beam, interlinked in a three- hinged configuration to make a sta- tically determinate frame. This eliminates difficulties associated with developing rigidity at joints where large moments and shears are involved.

tators in a structure measuring 16.60 metres wide and 152 metres long, con- sisting of 25 bays of 6 metres. Three alternative methods of construction were considered by the district en- gineer before a decision was made in favour of a prestressed structure. Re- inforced concrete was ruled out be- cause the resulting members were excessively large, and structural steel presented problems of time and cost in acquiring the material.

The basic prestressed structural and the column.

Points of hinge connections are at the socket bases of the girder and column, which are linked together by the foundation tie beam, and at the connection between the bleacher girder

Far East BUILDER, August 1969

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