Rio-Niteroi Bridge

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Rio-Niterói Bridge ,the sixth longest  bridge in the world and the longest prestressed concrete bridge in the southern hemisphere also known as President Costa e Silva Bridge . It runs 13.290 kilometres (8.258 mi) long – 8.836 kilometres (5.490 mi) over water and the bridge's 300-metre (980 ft) central span is 72 metres (236 ft) high in order to allow the passage of hundreds of ships entering and leaving the bay every month. OVER-WATER APPROACHES The over-water approach spans consist of twin precast post tensioned concrete box girders constant span length of 80 m is used for the continuous spans. Expansion joints are provided 20 m from the piers in every fifth or sixth span. The structure depth is 4.7 m. The piers for the approach structure are of cellular reinforced concrete and rest on footing blocks near the water surface and on 2-m-diameter reinforced concrete piles reaching to competent founding strata below water. Precast concrete segments were cast in a yard, barged...
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Earthquake-Resistant Brick

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RESEARCHERS IN Spain are developing an earthquake-resistant brick that they say could be incorporated into interior brick walls to stabilize them during seismic events. Dubbed Sisbrick by its creators at the Universitat Politècnica de València, the material is capable of absorbing greater horizontal movements than is the case with standard brick while still supporting vertical loads that can affect a building’s structural integrity.
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The bricks are designed to be arranged in a pattern within partition walls made mostly of standard bricks, and the researchers say that Sisbrick would enable such a wall to absorb three times as much horizontal movement as a typical brick wall. The arrangement would essentially isolate the wall from the building’s structural frame during a seismic event, increasing its stability and preventing a potentially catastrophic load transfer from the wall to the frame.

Francisco J. Pallarés, Ph.D., the principal researcher on the project, explained that Sisbrick greatly reduces the structural effects of brick walls, which exhibit complex and sometimes unpredictable behavior during earthquakes. The new material would lead to more predictable building behavior and therefore a more accurate structural design.
“This is a product that is new and unique. There is nothing like it on the market,” Pallarés said in written responses to questions from Civil Engineering. “It must be seen as a security system that protects the building structure from the infill interaction and reduces the stresses in the masonry panels.”

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