|
The concrete (usually with steel bar) is poured directly into the stable and solid roadbed, and the new line of ordinary sleeper and gravel bed is not used. This kind of line is clean, suitable for large volume and difficult maintenance area, especially for tunnel, underground railway, port wharf and stone road base. But its construction investment is big, if because of the construction slapdash or basement instability, concrete layer fracture, cure difficulty. China's overall Taoist route in the tunnel is more than 300 kilometers long
The gate is a detector that detects if there are metal objects, or metal detection doors. Mainly used in airports, stations, large conferences and other popular public places to check people's physical hidden metal objects, such as guns, controlled knives and so on. When the inspectors from security through, carries on the body shape of metal more than according to the weight, quantity or predefined parameter value, the security immediately alarm, and display alarm caused by metal and location, make security personnel find such person carry metal items in a timely manner
Four-wheel drive, or 4WD in short, was the best way to navigate rough terrain with your sports utility vehicle for many years, but all-wheel drive, also known as AWD in short, appears to have taken over industry and has become available even on midsize sedans in addition to SUVs. Though many people believe these are same form of vehicle feature, these are, in fact, quite different.
New Car Buying Tips--


Copyright ?1998-2017 Technews Corp, All rights reserved
|
