英语翻译1.the study’s life-cycle analysis estimates indirect cos

英语翻译
1.the study’s life-cycle analysis estimates indirect costs to the user due to traffic delays and lost productivity at more than 10 times the direct cost of repair.
2.In the United States,nearly 180,000 of the 600,000 bridges are either structurally deficient or functionally obsolete (Transportation Research Board 2006).
3.Reinforced concrete (RC) is another example of composite material,which combines reinforcing steel and concrete matrix to create a composite material having some of the advantages of both steel and concrete.
还有请问一下LDF这个缩写是什么意思?原句如下
LDF of supporting steel stringers.Results show that the strip method specified in the AASHTO LRFD specification (AASHTO 2004) as an approximate method of analysis can also be applied to unconventional FRP decks as a practical method.However,different strip width equations have to be determined by either FEM or experimental methods for different types of FRP decks.