HomeMy WebLinkAbout750769.tiff WELD '� ' 'OUNT COLO ►4D ®
March 25 , 1975
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1 — For Info To Roy Moser
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Design of County Roads
Subject: On Or Before
South Weld County
As per your request we have made a preliminary design of a
typical county road section for the Prospect Valley Area .
We have made several basic design assumptions regarding
existing soil conditions and traffic loading but these
assumptions should be practical for this preliminary design .
The following design is based on standard weight trucks ,
32 , 000 lbs per axle and does not take into account any over-
loaded vehicles .
A typical required section would be :
2" asphaltic concrete surface
6" crushed stone base •
1 " stone subbase
I '2" Total thickness
The estimated cost per mile for the above road is $52 , 000 .
*(4- S°.
Richard L. Straub
mfm
•
750769
exceed 2.49. The required structural design is to be determined special analysis.
e procedures described herein for the full selected design
ad d with the subbase and/or base course thickness (es)
calculated on the basis of a bituminous mot as the surface.
7-210.08 DESIGNATING STRUCTURAL DESIGN
The plans for Stage I construction should include the INFORMATION ON PLANS
necessary information to describe the complete structural
design as well as the portion to be constructed in Stage 2.
Sufficient information on the determined structural design
It is important that Stage 2 construction be scheduled and should be included on the typical cross section sheet of plans
performed before any major distress develops in the base to permit checking of the plans and special provisions.
course. Otherwise, satisfactory performance of the completed Information will be needed on the structural design traffic, the
pavement cannot be expected. In the event that a major distress design period, the classification of road or street, the support
should occur in a base course before the Stage 2 construction value of the roadbed soils, the structural. number, and the
can be accomplished, a re-evaluation of the pavement'design types and coefficient values for the materials to be used in the
will be required, and such cases should be referred to the surface course, base course, and subbase. It is recommended
Bureau of Design or Bureau of Local Roads and Streets for that the information be shown as illustrated in Figure 7-210.08.
•
STRUCTURAL DESIGN TRAFFIC: Year )9 E'5- ; P.C. - ZSO r
U.S. - Jr15 ; M.U. - 7S
..411 CLASS ROADS AND STREETS
MINIMUM SOIL SUPPORT: CBR - IO (Sta. 0+00 (a (5*0a )
CBR • (Sta. — to — 7
PER CENT OF S.D.T. IN DESIGN LANE: Up - 509 ; US - 5-p'/• r
•
5604
. 28 Dt - ).75 (Sta. OtOO to )S10o )
Dt (Sta. to '� )
•
'PAVEMENT STRUCTURE MATERIALS:
SURFACE COURSE TYPE: 2 � s-1 ; al - - 2O
BASE COURSE TYPE: .4•
B8-5 ; a2 - .
SUBBASE TYPE: 4 GkAUEL- ("-RADC )1 0.3 . )1
•
Figure 7-210.08
riN r-, 2/•
r. .TG F= S7Z PAYE M'-ti Desi wu MARCILz 4 197
From "DE:AGaa OF A5pHALT FAVE:1tx1Tn — ILL!JJIS OIU S/onn „F N/GP kN➢S
PAUEMa)T CLASS = n
DESIGN PER1o0 = 20 YEARS
STRUCTURAL DE5160 MIFF/C. = SOo ADT (AVE. DAILY rPAFFIC) AS5w1CD
DESIGN LANE = 50 70 of ADT frai"EQ
op Soo AOT ) PC - z.-.5o u5 = 1'75„ MU = 7S
TRAFFIC., FR CT02 ; 05)N4 Etlun T7oN FOR. GI-Ass I[E Ron us �
TF 0. 2. r (o.wcxOpXPC1 + x05xsu)+ 69,9o,yOrIMU)]
L 000, 000
T.F. ' zo I (.19cx .sAt ) +(sE-.77ox.1-x /75). 1,53.si o,� • S x 7�
L ))00o5000
T.F, _ • 280
C.5, R, = IO (CALIFoilu,A 5eA0. ,G u PA no) ASSunE1)
57RVCTWRAL. No ( DT) 1.75 FR•u F14, 9- tor.orb
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MIN1/1UN RE9uIR.EMENTS s -
SURFACE CouRSE = a1/22" - E,-z oR z" SI133 84-
'SASE Cou&SC = e" - GPAUEL oR C.Pu5HED s7M161 7Y➢E .8„
5 Ub13Ase = q°- GRAOe )I (IF uSED>
CoEFF)GeN7:,
5-2 SuRFACE CCou&SE _ . Z,
CRUSHCO 5TONe or- GRAVEL -TYPE'g" CPC r) a -I
CA LCu LAT)O,)
D7 = o l D, -/- 0. Dz D� = A`,PHALT TH I CKNES5
Dye ms6 COURSE
1.75 a .2D + . 1X8"
-4.75 = DI
USE S" OF SURFACE Cease 8 GRAu0. 'SASE Cookse
I «_- \
I r. 3�
AL.SJ CAVLD USE
?.7s = . t2" + . z‘{ x D2 * J) A
/.9 5- = •4 4 ,24 O 1- .44
2.
3.'79 = pZ
Z ,ugpf+ce eou2SE (non».ttr1 s-l)
9 DRSe Cot4st (ASPHALT) 6-s
j
7 4
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