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Chapter 4
<br /> LG i3WOLUNIL I_ZOAD DESIGN
<br /> Pavement structural design for lou-volume roads is basic step-bv-step procedures dcscribcd in Cl:cptcr 1
<br /> divided into thrr categories: The primary difference in the design for !ow-vciiume
<br /> roads is the level of reliability that may be used.
<br /> (1) flexible pavements, Because of their relative!ow usar and tnc a.so•:fated
<br /> low level of risk, the !evel of reliability rcconmcnded
<br /> (2) rigid pavements, and for low-volume road (lz:sign is 50 percent. The user
<br /> may, however, design for tligiler le!e:s of 60 to 80
<br /> (3) aggregate-surfaced reads. percent, dcpendir,g on the aetuA pro;ectrd levei of
<br /> traffic and the fC3Sibi1ltV,Of r'ehabilitatiOn,iripor once
<br /> This chapter covers the design of low-volume roads for of cored or, etc.
<br /> these three surface types using proc-dares bued on
<br /> design charts(nomographs)ar_d desip'i catalogs.T~:ese If,in estimating an effective rt:�,ilient mo, tultts of the
<br /> two procedures are covered in Sec-ions 4.1 and 4.2, roadbed material (M..) or r:n effective modulus of
<br /> respectively. For surface treatment or chip setil pave- subg'rade reaction (k), it is not possiblc to determine
<br /> t:ent structures,the procedures for flexible pavements th-!ieni^hs of the sra_,c;:.s or even'the s:asor�-i roadbed
<br /> =y be used. soil res:li r.L m..d ui1, .he following siq!zestiarns shou!d
<br /> ;. c:_d.
<br /> B,:cz Lc!__pri=ry ba6s*,or z..I rz=on2l rav=,=nt
<br /> p C t: r^ a:= J C:CI1 _^.rar.-Ho:S Ii
<br /> r..., t:`a'.%1 C�. . E Y'":E'Li. i ^J'.." .1 ^ r e �►
<br /> t.W'. �-.r t vr., n t IEt{1'CSu w�..Y1t}TtISI
<br /> 3Uau»''ri1, S3* 5-it is IIe=ss-_ :n iurCt a. L3iia
<br /> l:S: ".` �i� �.5 L'L' t1:.^t 5 ',^ .?.'>.� �^ r {�_�l`a } Z�G CS.l^..^.u'a 't
<br /> des:c aPp7o c a for iow-volun:t rLL is_ r' : CSS :'t Bz$.z-6 a: ,.N ::�:=gIO ZJ-,.n2`d=., m=" 1 4!lie 4.1
<br /> I-v,, , )w Lte traffic hz ei is or M at t:,.c dLt'i^i:Ll0-_ ;S e U7-:^!t to ;1e1' the erzFtli.
<br /> i:l€ : tOa
<br /> between a canobiles anC trucks. ecr: .:__ngT11C�ffeCLivcroad'zitdsJilres�, i::,"i• zi ,al uh:s
<br /> (Section,. 2.3.1) for !lwxii:,e pzy-^ent dc:t`r, or tr,e
<br /> Since many city stre:ts and county roads that fai'. cffectivc nodulus ofsub,=f?r:Teac:;on(Section 3.:.1)
<br /> ur_der the low-volume C�tegory may still earn.signs- for ri d pavement dcsi`ri,
<br /> cant Ie•.°eis of truck trffic, the maximum number of
<br /> 18-kip c.SAL apolic ltions considered for flexible and .' easo::cll:oadbedSoill?esdie'rt!tfodz,—rj. Tabie4.2
<br /> rigid pavement design is 700,000 to 1 million. The provides rr_adbed soil resilient modulus values that
<br /> practical minimum traffic level that can be cersidered may be used for low-volume road desi fm if the user can
<br /> for any flexible or rigid pavement during a given classify the general quality of the roadbed material as a
<br /> performance period is about 50,000 18-kip ES."•,L foundation for thepavementst: cture.Ifthtsuggestcd
<br /> applications. For the aggrgate-surfaced(gravel)roads - values in this table are cembired with t`'e suggested
<br /> used for many county ar.4 forest roads, the maximum season let eths identified in the previous s:ction,
<br /> trafiic level considered is A,00018-kipESALapplica- effective roadbed soil resilient modulus values (for
<br /> tions, while the practical minimurn level (during a flexible pavement design only) can be gcaera:ed for
<br /> single performance period) is 10,000. each of the six U.S.climatic regions.These MR.'aloes
<br /> are pres,nted in Table 4.3.
<br /> 4.1 DE''IGN CH.' RT PROCEDURES
<br /> 4.1.2 A!;^rcgste-Surfaced Roads
<br /> 4.1.1 1=le dble snd Fibid Pa%ements Tl:'. ..asis- for[reatia:*t r:C C:',..tS Ci snit.,.^..j!tt101St',!'.
<br /> c aw'`. on^. :S ,
<br /> road L. rl:' l':;..�, rti.,......_S .,lr �a%,. i: 1 ' t�'
<br /> t' - r ` ,=n
<br /> r"Ind pavemz:nts
<br /> or
<br /> 5;:. t': C ?,i^ li• i L).;c,. er, .,e
<br /> r:: :s 0:1 t::
<br /> ..-
<br /> '
<br /> L; ,• _.:file:, ri.:,.�r.::;l1,i:S
<br /> rC.: 1:e .nits (de`.Cioprd In Lhap(.r :) as %%ell ai t::C a dra=`t!:e,:l �J!UtI0i1. It Il Ii1:2J;Lat1I t0 [ (C l!l:t
<br /> E
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