Farquharson continued wind tunnel tests. He concluded that the “cumulative effected of undampened rhythmic forces” had produced “intense resonant oscillation.” in other words, the bridge’s lightness, combined with an accumulation of wind pressure on the 8-foot solid plate girder and ...

Trusses do an important job. Trusses are a building invention that helps distribute the weight of the roof more evenly to the outer walls. Trusses are necessary for a roof to be supported appropriately. A truss is triangularly shaped, or ...

The great wall of china was built over centuries by china’s emperors to protect their territory. Today, it stretches for thousands of miles along china’s historic northern border. Why Was the Great Wall of China Built? The Great Wall of ...

By the time builders had finished the third of eight planned stories about five years later, the tower’s foundation had begun to settle unevenly on the ground beneath it, a dense mixture of clay, sand and shells. As a result, ...

Moisture/air beneath the paint film is now trapped. When the painted surface is heated by the sun, the moisture/air expands and blisters form because it cannot escape freely. Blistering is often quite severe on exterior weatherboards facing north or west ...

Moist curing is a common method of concrete curing. It involves wetting the concrete slab often with water (5-7 times per day) for the first 7 days. This method ensures your concrete slab will be solid and durable, because it ...

By the time builders had finished the third of eight planned stories about five years later, the tower’s foundation had settled unevenly on the ground beneath it, a dense mixture of clay, sand and shells. As a result, the structure ...

Egypt’s pharaohs expected to become gods in the afterlife. To prepare for the next world they erected temples to the gods and massive pyramid tombs for themselves—filled with everything each ruler would need to guide and sustain himself in the ...

Leed certification helps the environment by saving energy, water, coal and diverting waste. Leed-certified buildings also help reduce pollution and outdoor air quality by reducing smog in major industrialized communities. If your building is leed certified, you will also have ...

The heat produced by concrete during curing is called heat of hydration. This exothermic reaction occurs when water and cement react. The amount of heat produced during the reaction is largely related to the composition and fineness of the cement. ...