asphalt 和 pitch什么区别

Walking barefoot on the asphalt pavement makes the bottom of your feet callous.
callous翻成什么比较好?

求英语达人做题,
some builders did not cover flat roofs with asphalt .
they are starting to make rooftop green.
------instead of covering flat roofs with asphalt,some builders are starting to make rooftops are starting to make rooftops green
1 I have bought a house near my office building ang now I can walk to work .
I don't go by bus.
2 He wanted to do what he liked.
He didn"t want to follow his parents" advice all the time.
3 To live clean and green,we need to install solar-systems systems in our buildings .
we should not use traditional energy sources
4 He decided that he would drive back to town
He would not stay for the night at the hotel .
5.If we work hard,we may be able to finish the hotel,
We may not stay for the nighr at the hotel,
6,Why do you want to meet me here
why don"t you want to meet me at my hotel?

英语翻译
PRODUCT
PENETRATION GRADE (180-200 PEN )
ASPHALT CEMENT (40-50 PEN)
ASPHALT CEMENT (60-70 PEN)
ASPHALT CEMENT (85-100 PEN)
ASPHALT CEMENT (AC-20)
ASPHALT CEMENT (AC-30)
PERFORMANCE GRADE PG64-22
PERFORMANCE GRADE PG64-28
CUTBACK ASPHALT GRADE RC-250
ASPHALT ROOFERS FLUX

英语翻译
bottom of the asphalt surface or the stabilized base and propagate
to the surface under a wheel load 1Huang 2004; Song et al.2005;
AASHTO 20022.However,some recent and current studies have
indicated that cracks 1load related2 can initiate at the top and
propagate downward 1AASHTO 20022.As noted by Desai
120072,when using the classical fracture mechanics approach,it
is necessary to introduce a crack of arbitrary dimension a priori.
Because cracks can develop at other locations depending upon the
geometry,material properties,and loading,this approach may be
limited in pavement applications.To this end,the disturbed state
concept 1DSC2 was used by Desai 120072 to evaluate the initiation
and location of microcracks and their growth in a more rational
manner,given the geometry,properties,and loading conditions of
the pavement structure.Other studies have also been undertaken
previously to obtain a better understanding of the cracking
mechanisms in asphalt pavements 1Majidzadeh 1970; Majidzadeh
et al.1971; Monismith et al.1971; Lytton and Zollinger 1993;
Kim and El Hussein 1995; Jacobs et al.19962.These studies,
however,were generally limited to experiments,stationary
cracks,and to fracture of asphalt concrete 1AC2.Other studies
1Sobhan1997; Cavey et al.1995; NCHRP 19922 have evaluated
the field and laboratory properties such as flexural strength and
tensile strength of stabilized aggregate bases,without any consideration
to numerical modeling.