jo flere ulykker i lande som kina med høj vækst, sund økonomi og eksportoverskud der har råd til at genopbygge
jo mere økonomisk vækst
så jordskælv er godt for den globale vækst
i nedenstående artikel er der for en gangs skyld data for antal af kvadratmeter bygget i 2006
dem jeg har fundet i tidens løb siger ikke altid det samme og dette tal indeholder vidst både erhverv og bolig
men såvidt jeg kan regne ud svarer det til 18 mio boliger a 100 kvadratmeter om året, når man regner det i den enhed uanset hvilken form for byggeri der er tale om (1.8 bil square meters)
og så kan man nemt sammenligne det med at usa bygger mindre end 1 mio boliger i øjeblikket fra et peak på 2.3 af formentlig huse på mere end 100 kvadratmeter, medens usa selvfølgelig bygger en masse non-housing byggeri, hvor det er svært at skønne hvor stort etagearalet er, men det er formodentligt mindre end boligarealet
så det viser lidt om dimensionerne i størrelsen af kinas byggeri, så det er en meget stor dværg, nærmest en ny udgave af ham, der skulle navles til jorden med pæle, jeg husker ikke lige hvad man kaldte ham, for det var vel ikke oliver twist, men han var i hvert fald en kæmpe
og så er byggeriet steget yderligere med 20-25% i 2007 og også indtil nu i år
det interessante er at stigningen i bestanden af bygninger stiger så hurtigt at behovet for opvarmning, airconditioning og el til diverse el produkter i huset mm stiger voldsomt og det vil fortsætte med at stige også hvis byggeriet skulle gå hen og falde
det er der en vis risiko for at det gør med den stigning i inflation, rente og kredirbegrænsninger, kina oplever i øjeblikket
men det får ikke energiforbruget til at falde, det vil fortsat vokse med mere end 10% oom året
men det vil ramme stålforbruget og forbruget af byggematerialer mm samt maskiner dertil
det betyder at risikoen ved at investere i kul og olie er mindre end for jernmalm i øjeblikket, hvis man ser det på lidt længere sigt
det volsomme omfang af byggeriet er selvfølgelig også baggrunden for at kinas salg af heavy trucks nu er på samme niveau som usa og europa tilsammen fra 35.000 i 2000 til 650.000 i år og bestanden steget fra 2 mio i 2006 til 2.5 mio i 2007 og 3.1 mio i 2008 og de bruger jo meget olie og kører ikke på vand
China Reassesses Construction
By JAMES T. AREDDY, GORDON FAIRCLOUGH and SHAI OSTER
May 24, 2008
At the back of a junkyard crowded with dirty pipes in Mianyang, China, two men were at work this past week straightening tangled mountains of rusty reinforcing bars and rebundling them for sale.
"It's strong enough," said Zeng Shuncai, one of the men. He said he is expecting sales to boom now that so many families will need to build new homes in this city near the epicenter of last week's giant earthquake in southwestern China. Engineers say such secondhand steel isn't as strong as new rebar, but it sells for about $100 less per metric ton.
James T. Areddy
Fifteen-year-old Cheng Ruixiang points to what used to be his school, Juyuan Middle School in Dujiangyan, China.
As China begins the monumental task of rebuilding housing for an estimated five million left homeless by the quake, it is also undertaking a major re-evaluation of construction practices that could change the way people live well beyond the areas that were leveled by the 7.9-magnitude quake.
Many say substandard construction exacerbated the quake's toll. Nearly 56,000 people have been confirmed dead, and about 25,000 remain missing. The severity of the temblor, which was China's worst in three decades and exceeded the level foreseen by government building codes, magnified the damage.
But architects and engineers say many of the simple four- and five-story structures that crumbled should have been able to withstand such a strong quake -- if they had been built properly. They say many buildings don't appear to have had enough steel reinforcing rods, or rebar, in their concrete to withstand the quake's rapid, lateral shaking.
These structures "should not have collapsed," said Silas Chiow, director of China operations for Skidmore, Owings & Merrill, a U.S. architecture firm that is building some of tallest skyscrapers in China.
"The supervision of the quality of construction and engineering should be improved," says Li Zhengliang, an engineer who is vice director of Chongqing University's school of architecture and civil engineering.
Mr. Li, who traveled to the quake zone to inspect buildings, says that in many cases, he and his colleagues discovered "inferior" materials were used in the construction of structures that collapsed. Many older buildings hadn't been renovated to meet upgraded seismic regulations, he said. Chen Zhong, a senior official in charge of quality standards at the Ministry of Housing and Urban-Rural Development, says "seismic-fortification standards for buildings need to be revised," given advances in technology and China's ability to afford stronger regulation.
Many of China's major population centers -- including the capital, Beijing, and booming manufacturing areas in southeastern China -- are in areas of seismic activity. Earthquakes have caused more deaths in China since 1949 than any other type of natural disaster.
In the aftermath of the May 12 quake, the central government has launched an investigation into construction quality of schools and has acknowledged that almost 7,000 classrooms and dorm rooms were destroyed.
Some provinces, meanwhile, are already making changes. "The earthquake in Sichuan sounded the warning bell for us," said Luo Chongmin, director of the education bureau in neighboring Yunnan province, which escaped major quake damage. There, authorities have already ordered the demolition of numerous unsafe school buildings. "In newly built and renovated schoolhouses, antiearthquake precautions need to be strengthened," he said.
Other developing countries have faced similar problems as economic growth has driven construction faster than regulatory oversight has been able to keep up. Thailand and South Korea experienced a series of major construction failures in the mid-1990s, after which regulations and enforcement were tightened.
Experts say China's building rules today are on a par with those of many Western countries. Earthquake regulations were tightened considerably after China's last major quake, in 1976, which killed hundreds of thousands of people.
The problem, experts say, is that builders often don't follow the rules. "Contractors will do what they can to save money. It's a fairly common phenomenon in a heated market where demand is high and there is a lack of resources," says Ashley Howlett, a lawyer at Jones Day in Beijing who specializes in construction.
Conditions are worst outside big cities, where hundreds of millions of China's less-well-off citizens live. Last year, for example, a bridge under construction in central China collapsed, killing 64 people. A highway-department official was charged with lowering technical standards in exchange for bribes from the construction company.
Another issue: The sheer pace of China's construction boom, which makes it hard for authorities to monitor. China built 1.8 billion square meters (2.16 billion square yards) of property in 2006, according to government figures. In Sichuan, much of the new construction has come in villages and burgeoning small towns that have rising incomes but few architects or engineers and little government oversight.
"I think this is a huge lesson," says Xiao Yan, an earthquake engineer at Hunan University's civil-engineering college and a professor at the University of Southern California. "The government really has to look after the life and way of construction in the rural regions."
Many farmers have moved from traditional wood-and-adobe homes with clay-tile roofs to multistory structures made from hollow-core concrete slabs and masonry. Mr. Xiao, who has been touring quake-hit parts of Sichuan, says that type of construction is "like a time bomb."
Construction methods can also cause problems. Using precast concrete slabs, for example, is less effective to fortify a building against seismic shocks than casting concrete portions in place.
Even the quality of new-construction steel tends to be of a lower grade than that manufactured in many developed countries, experts say. Rural buyers often purchase from smaller steel mills, some of which operate illegally, says Huang He, an analyst at Mysteel Research Institute in Shanghai.
"In more-remote or rural areas, I doubt if regulations can be enforced completely," says Zhang Limin, a professor in the civil-engineering department at Hong Kong University of Science & Technology who has worked as an engineer on hydropower projects in China. "I think that's one of the main reasons for the amount of damage."
AI
