A covered bridge is a timber-truss bridge with a roof, decking, and siding, which in most covered bridges create an almost complete enclosure. The purpose of the covering is to protect the wooden structural members from the weather. Uncovered wooden bridges typically have a lifespan of only 20 years because of the effects of rain and sun, but a covered bridge could last over 100 years. Once common, only about 1 in 10 survived the 20th century. The relatively small number of surviving bridges is due to deliberate replacement, neglect, and the high cost of restoration.
圖片編號:
239671430
拍攝者:
Debchephotography
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授權類型 | 尺寸 | 像素 | 格式 | 點數 | |
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標準授權 | XS | 320 x 480 | JPG | 13 | |
標準授權 | S | 533 x 800 | JPG | 15 | |
標準授權 | M | 1414 x 2121 | JPG | 18 | |
標準授權 | L | 1825 x 2738 | JPG | 20 | |
標準授權 | XL | 2309 x 3464 | JPG | 22 | |
標準授權 | MAX | 2912 x 4368 | JPG | 23 | |
標準授權 | TIFF | 4118 x 6177 | TIF | 39 | |
進階授權 | WEL | 2912 x 4368 | JPG | 88 | |
進階授權 | PEL | 2912 x 4368 | JPG | 88 | |
進階授權 | UEL | 2912 x 4368 | JPG | 88 |
XS
S
M
L
XL
MAX
TIFF
WEL
PEL
UEL
標準授權 | 320 x 480 px | JPG | 13 點 |
標準授權 | 533 x 800 px | JPG | 15 點 |
標準授權 | 1414 x 2121 px | JPG | 18 點 |
標準授權 | 1825 x 2738 px | JPG | 20 點 |
標準授權 | 2309 x 3464 px | JPG | 22 點 |
標準授權 | 2912 x 4368 px | JPG | 23 點 |
標準授權 | 4118 x 6177 px | TIF | 39 點 |
進階授權 | 2912 x 4368 px | JPG | 88 點 |
進階授權 | 2912 x 4368 px | JPG | 88 點 |
進階授權 | 2912 x 4368 px | JPG | 88 點 |