An earthquake generated within the Pacific Ocean floor will generate a tsunami, which is actually a series of very long waves. Large tsunamis which travel to the ocean floor to the surface are dangerous to human health, property, and infrastructure. Long lasting effects of tsunami destruction can be felt beyond the coastline.
construction destruction crack
The vibrations from an earthquake can lead to ground displacement and surface rupture. The surface rupture can cause other hazards, as well as damage to roads and buildings. In this example, the surface rupture has caused large cracks and the collapse of a paved road. This could lead to injuries, loss of life, or impede people from getting home or to work.
So Truman kicked off what we now refer to as the "Truman reconstruction," a massive four-year project during which the entire interior of the building -- everything but the brick outer shell -- was completely demolished and rebuilt. In other words, to keep the building from falling in on itself, they had to do this:
The Leaning Tower of Pisa is only famous because its builders were fuckups -- due to an inadequate foundation set in unstable soil, the tower has been slowly tilting perilously closer and closer to nervous ground-based tourists ever since its construction in the 1100s. And on multiple occasions, it came damn close to becoming the Horizontal Tower of Pisa.
By Anirban Sinha Roy: At least ten houses in central Kolkata's Bowbazar were evacuated early in the morning on Friday after major cracks appeared in the structures, likely to have been caused by metro railway construction in the area. The Kolkata Metro Rail Corp. Ltd (KMRCL) have been given an official notice to shift the people residing there to several local hotels.
Many families are homeless since dawn. The police have ordered to vacate the area. Meanwhile, residents are angry with the Metro Rail authorities after repeated cracks in their houses. Allegedly, Metro Rail representatives did not come even after informing them about the crack.
It started in Bowbazar since the start of East-West Metro Rail work in 2019. Houses in the area cracked one after another. Some of the even collapsed in 2019. More than 600 residents were evacuated during that time. Even in May this year, several houses in Durgapituri Lane, Madan Dutt Lane suffered cracks. At that time local residents were temporarily shifted to hotels.
Cracks were seen in several houses on Friday morning at Madan Dutta lane of Bowbazar. It is known that the crack occurred around 4:30 in the morning. At least 10 houses suffered cracks. Residents of the houses have been sitting on the streets with bags packed since the early hours of the night. The police ordered to evacuate the area. The affected houses have been surrounded by barricades.
Meanwhile, the area councilor Biswarup Dey has already reached the spot. He reached the spot around 5:30 am. He also expressed anger about the whole incident. He said, Metro rail authorities are treating people like guinea pigs. Who will take responsibility for these people? Bowbazar Street is headed for destruction only for Metro Authority. We have sought a written statement from the Metro Rail authorities."
The continuous AE evaluation in composites was earlier reported [1,2,3] and this technique has been applied to determine crack propagation in the fracture process in cement composites with and without reinforcement [4,5]. The acoustic emission (AE) events sum was also recorded for easier recognition of the first crack and crack propagation process [6,7,8].
Figure 2 presents the mechanical effects of the ESD (Eng. elastic range, strengthening, deflection control) cement composites with the corresponding acoustic effects and compiled acoustic spectra with various amplitudes corresponding to different mechanical effects (reinforcement breaking, pull-out, macrocracks, and microcracking).
Four-point bending test: (a) sample before the test, (b) first crack at fcr point, (c) multicracking (micro- and macrocracks), (d) destruction - propagation process, (e) view after the test.
The sound intensity of the multicracking was similar to background noise spectrum, but with a slightly greater range of amplitudes and significant amplitudes in a narrow frequency range (Figure 4c and Figure 5c).
Macrocracks showed the highest sound intensity. What is worth noting is the fact that the corresponding spectra were not characterized by the greatest amplitude range. The spectra were located the highest (Figure 4b).
In Nagasaki, 9" brick walls were heavily cracked to 5,000 feet, were moderately cracked to 6,000 feet, and slightly cracked to 8,000 feet. In both cities, light concrete buildings collapsed out to 4,700 feet.
In Nagasaki 14,000 or 27% of 52,000 residences were completely destroyed and 5,40O, or 10% were half destroyed. Only 12% remained undamaged. This destruction was limited by the layout of the city. The following is a summary of the damage to buildings in Nagasaki as determined from a ground survey made by the Japanese:
In Nagasaki, buildings with structural steel frames, principally the Mitsubishi Plant as far as 6,000 feet from X were severely damaged; these buildings were typical of wartime mill construction in America and Great Britain, except that some of the frames were somewhat less substantial. The damage consisted of windows broken out (100%), steel sashes ripped out or bent, corrugated metal or corrugated asbestos roofs and sidings ripped off, roofs bent or destroyed, roof trusses collapsed, columns bent and cracked and concrete foundations for columns rotated. Damage to buildings with structural steel frames was more severe where the buildings received the effect of the blast on their sides than where the blast hit the ends of buildings, because the buildings had more stiffness (resistance to negative moment at the top of columns) in a longitudinal direction. Many of the lightly constructed steel frame buildings collapsed completely while some of the heavily constructed (to carry the weight of heavy cranes and loads) were stripped of roof and siding, but the frames were only partially injured.
The next most seriously damaged area in Nagasaki lies outside the 2.9 square miles just described, and embraces approximately 4.2 square miles of which 29% was built up. The damage from blast and fire was moderate here, but in some sections (portions of main business districts) many secondary fires started and spread rapidly, resulting in about as much over-all destruction as in areas much closer to X.
As intended, the bomb was exploded at an almost ideal location over Nagasaki to do the maximum damage to industry, including the Mitsubishi Steel and Arms Works, the Mitsubishi-Urakami Ordnance Works (Torpedo Works), and numerous factories, factory training schools, and other industrial establishments, with a minimum destruction of dwellings and consequently, a minimum amount of casualties. Had the bomb been dropped farther south, the Mitsubishi-Urakami Ordnance Works would not have been so severely damaged, but the main business and residential districts of Nagasaki would have sustained much greater damage casualties.
The damage sustained by reinforced concrete buildings depended both on the proximity to X and the type and strength of the reinforced concrete construction. Some of the buildings with reinforced concrete frames also had reinforced concrete walls, ceilings, and partitions, while others had brick or concrete tile walls covered either with plaster or ornamental stone, with partitions of metal, glass, and plaster. With the exception of the Nagasaki Medical School and Hospital group, which was designed to withstand earthquakes and was therefore of heavier construction than most American structures, most of the reinforced concrete structures could be classified only as fair, with concrete of low strength and density, with many of the columns, beams, and slabs underdesigned and improperly reinforced. These facts account for some of the structural failures which occured.
In general, the atomic bomb explosion damaged all windows and ripped out, bent, or twisted most of the steel window or door sashes, ripped doors from hinges, damaged all suspended wood, metal, and plaster ceilings. The blast concussion also caused great damage to equipment by tumbling and battering. Fires generally of secondary origin consumed practically all combustible material, caused plaster to crack off, burned all wooden trim, stair covering, wooden frames of wooden suspended ceilings, beds, mattresses, and mats, and fused glass, ruined all equipment not already destroyed by the blast, ruined all electrical wiring, plumbing, and caused spalling of concrete columns and beams in many of the rooms.
Although the blast damaged many bridges to some extent, bridge damage was on the whole slight in comparison to that suffered by buildings. The damage varied from only damaged railings to complete destruction of the superstructure. Some of the bridges were wrecked and the spans were shoved off their piers and into the river bed below by the force of the blast. Others, particularly steel plate girder bridges, were badly buckled by the blast pressure. None of the failures observed could be attributed to inadequate design or structural weaknesses.
In many areas, coral reefs are destroyed when coral heads and brightly-colored reef fishes are collected for the aquarium and jewelry trade. Careless or untrained divers can trample fragile corals, and many fishing techniques can be destructive. In blast fishing, dynamite or other heavy explosives are detonated to startle fish out of hiding places. This practice indiscriminately kills other species and can crack and stress corals so much that they expel their zooxanthellae. As a result, large sections of reefs can be destroyed. Cyanide fishing, which involves spraying or dumping cyanide onto reefs to stun and capture live fish, also kills coral polyps and degrades the reef habitat. More than 40 countries are affected by blast fishing, and more than 15 countries have reported cyanide fishing activities. 2ff7e9595c
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