handbook on highway design, Study Guides, Projects, Research of Transportation Engineering

Download handbook on highway design and more Study Guides, Projects, Research Transportation Engineering in PDF only on Docsity! JSS Mahavidyapeetha Sri Jayachamarajendra College Of Engineering Mysuru — 570 006 HIGHWAY ENGINEERING DESIGN DATA HAND BOOK (Geometric Design and Pavement Design) Compiled By Dr. P. Nanjundaswamy Professor of Civil Engineering ’ DEPARTMENT OF CIVIL ENGINEERING 2015 CONTENTS Page No. 1 GEOMETRIC DESIGN STANDARDS FOR NON-URBAN HIGHWAYS 1-9 1.1. Classification of Non-Urban Roads 1 1.2. Terrain Classification 1 1.3. Design Speed 1 1.4. Cross Section Elements 2 1.4.1 Cross Slope or Camber 2 1.4.2. Width of Pavement or Carriageway 2 1.4.3. Width of Roadway or Formation 2 1.4.4 Right of Way 3 1.5. Sight Distance 3 1.5.1 Stopping Sight Distance (SSD) 3 1.5.2 Overtaking Sight Distance (OSD) 3 1.6. Horizontal Alignment 4 1.6.1 Superelevation 4 1.6.2 Widening of Pavement on Horizontal Curves 6 1.6.3 Horizontal Transition Curves 7 1.6.4 Set-back Distance on Horizontal Curves 8 1.7. Vertical Alignment 8 1.7.1 Gradient 8 1.7.2 Length of Summit Curve 9 1.7.3 Length of Valley Curve 9 2 DESIGN OF FLEXIBLE PAVEMENTS 10-18 2.1 Design Traffic 10 2.2 Traffic growth rate 10 2.3 Design Life 10 2.4 Vehicle Damage Factor 11 2.5 Distribution of Commercial traffic over the carriageway 11 2.6 Design Criteria 12 2.7 Design Criteria 12 2.8 Design Charts and Catalogue 13 2.9 Pavement Composition 18 2.10 Final Remarks 18 1.4 CROSS SECTION ELEMENTS 1.4.1 Cross Slope or Camber Table 1.3 Recommended values of camber for different types of road surfaces sl Range of Camber in areas of No Types of Road Surface Heavy rainfall Light rainfall 1_| Cement concrete and high type bituminous surface | 1in 50 (2.0%) | 1in 60 (1.7%) 2 | Thin bituminous surface 1in 40 (2.5%) | 1in 50 (2.0%) 3__| Water bound macadam and gravel pavement 1 in 33 (3.0%) | 1in 40 (2.5%) 4 | Earth Road Lin 25 (4.0%) | 1in 33 (3.0%) 1.4.2 Width of Pavement or Carriageway Table 1.4 Recommended values for width of carriageway a Class of Road Width of Carriageway (m) 1. | Single lane 3.75 2. | Two lanes, without raised kerbs 7.0 3. | Two lanes, with raised kerbs 7.5 4 | Intermediate carriageway (except on important roads) 5.5 5 | Multi-lane pavements 3.5 m per lane Notes: ¢ The lane width of Expressways is 3.75 m in plain and rolling terrains and 3.5 min mountainous terrian ¢ The width of single lane for village roads may be decreased to 3.0m ¢ On urban roads without kerbs the single lane width may be decreased to 3.5 m and in access roads to residential areas to 3.0m ¢ ~The minimum width recommended for kerbed urban road is 5.5 m 1.4.3 Width of Roadway or Formation Table 1.5 Recommended values for width of roadway of various classes of roads Roadway width (m) S| Road Classification Plain & Rolling Mountainous No . & Steep terrain ; terrain National & State Highways 1 a. Single Lane 12.0 6.25 b. Two Lane 12.0 8.80 Major District Roads 2 a. Single Lane 9.0 4.75 b. Two Lane 9.0 a Other District Roads 3 a. Single Lane 75 4.75 b. Two Lane 9.0 a 4 | Village Roads — single lane 75 4.0 1.4.4 Right of Way Table 1.6 Recommended land width for different classes of non-urban roads . . . Mountainous & Plain & rolling terrain : sl steep terrain No Road Classification Open areas Built-up areas Open Built-up areas areas Normal | Range | Normal | Range | Normal | Normal 1 | Expressways 90 - - 60/30 2 | National & State Highways 45 30-60 30 30-60 24 20 3__| Major District Roads 25 25-30 20 15-25 18 15 4 | Other District Roads 15 15-25 15 15-20 15 12 5 _| Village Roads 12 12-18 10 10-15 9 9 1.5 SIGHT DISTANCE 1.5.1 Stopping Sight Distance (SSD) SSD = Lag distance + Braking distance 2 v SSD = vt +>———_ 1.1) °°" Fg £ 0.0In) (21.2) v Design speed (m/s) t Reaction time of driver (s) (2.5 seconds as per IRC guidelines) f Design longitudinal friction coefficient (Refer Table 1.7) g Acceleration due to gravity = 9.8 m/s? n Gradient of road (%) (+ for ascending and — for descending) Table 1.7 Recommended longitudinal friction coefficient for providing SSD Speed (km/h) 20-30 | 40 50 60 65 30 | 2100 Longitudinal friction coefficient 0.40 0.38 0.37 0.36 0.36 0.35 0.35 Table 1.8 Recommended Stopping Sight Distance for different speeds Speed (km/h) 20 25 30 40 50 60 65 80 100 SSD (m) 20 25 30 45 60 80 90 120 180 1.5.2 Overtaking Sight Distance (OSD) OSD = dy +d, +d3 OSD = vp t + (vp T +25) +0T Vz = (V* — 16) (As per IRC guidelines) s = (0.2 V5 +6) (As per IRC guidelines) T= J4s/a (1.2a) (1.2b) (1.2c) (1.2d) (1.2e) v = Design speed or Speed of overtaking vehicle (m/s) Vp = Speed of overtaken vehicle (m/s) t = Reaction time of driver (s) (2.0 seconds as per IRC guidelines) T = Time taken for overtaking operation (s) Ss = The minimum spacing between vehicles (m) ve = Design speed or Speed of overtaking vehicle (km/h) Vp = Speed of overtaken vehicle (km/h) a = Average acceleration during overtaking (m/s?) Table 1.9 Maximum overtaking acceleration at different speeds Speed (km/h) 25 30 40 50 65 80 100 Max (kmph/s) | 5.00 4.80 4.45 4.00 3.28 2.56 1.92 overtaking Acc (m/s?) 1.41 1.30 1.24 1.11 0.92 0.72 0.53 Table 1.10 Overtaking Sight Distance on two-lane highways for different speeds Speed (km/h) 40 50 60 65 80 100 SSD (m) 165 235 300 340 470 640 Note: © OSD = d, + dz for one-way roads © OSD = d, +d, + d3 for two-way roads e Intermediate Sight Distance (ISD) = 2 SSD ¢ Head Light Distance (HSD) = SSD 1.6 HORIZONTAL ALIGNMENT 1.6.1 Superelevation (e) pe et+f.=— 1.3) ha (2.3) e = Rate of superelevation ft = Design value of transverse or lateral friction coefficient (0.15 as per IRC guidelines) v= Design speed vehicle (m/s) R_ = _ Radius of the horizontal curve (m) 9 = Acceleration due to gravity = 9.8 m/s? Maximum Superelevation In order to account for mixed traffic conditions in India, IRC has defined the maximum limit of superelevation (€ 4) as given in Table 1.11 Table 1.11 Recommended maximum limit of superelevation 7% - Plain and rolling terrains and in snow bound areas 10% - Hillroads not bound by snow 4% - Urban road stretches with frequent intersections 1.6.3 Horizontal Transition Curves Length of Transition Curve (L,) A. Rate of Change of Centrifugal Acceleration L _v ° CR c-— d [0.5 <C < 08] ~ Gs 4yy ee SoS” B. Rate of Introduction of Superelevation 1, — EN _elw + Wen s 2 2 when pavement is rotated about centreline L, = EN =e(W + W,)N when pavement is rotated about inner edge C. Empirical formula _27v" L, = for plain and rolling terrains a2 L. = y“ for mountainous and steep terrains ° R v = Design speed (m/s) Cc = Rate of change of centrifugal acceleration (m/s?) R = Radius of horizontal curve (m) ve = Design speed (km/h) N - Rate at which superelevation is introduced (150 - Normal, 100 — Built up areas and 60 — Hill roads) E = Amount of Superelevation or Total raising of pavement (m) e = Rate of superelevation Ww = Width of pavement (m) WwW, = Extra width of pavement (m) . Pr ei is Note: Shift of transition curve is given by S = TAR (1.8a) (1.8b) (1.9a) (1.9b) (1.10a) (1.10b) 1.6.4 Set-back Distance on Horizontal Curves (m’) WhenL, = S m' = R—(R-—d)cos () (1.11) 2 . a 180S d 4.146 77 2n(R —d) legrees (1.11b) When L, < S 1 ay Cate) 1 (@ 1.12 m! = R~(R~ d)cos(5) + 2 sin(5) (1.12a) a 180L, d 4.126 77 2n(R — d) legrees (1.12b) L. = Length of the Curve (m) Ss = Sight Distance (m) (either SSD or OSD or ISD) R = Radius of horizontal curve (m) d = Distance between centerline of road to centerline of inside lane (m) a = Angle subtended at the center of horizontal curve (degrees) 1.7 Vertical Alignment 1.7.1 Gradient Table 1.14 Gradients for roads in different terrains ; Ruling Limiting Exceptional Ty f te ype orterrain gradient gradient gradient Plain or Rollin 3.3% 5.0% 6.7% 8 (1 in 30) (1 in 20) (1 in 15) Mountainous terrain and steep terrain having 5.0% 6.0% 7.0% elevation more than 3000 m above MSL (1 in 20) (1 in 16.7) (1 in 14.3) . . 6.0% 7.0 % 8.0 % steep terrain up to 3000 m height above MSL (1 in 16.7) (1 in 14.3) (1 in 12.5) 1.7.2 Length of Summit Curve (L) WhenL > S L NS? ~ (1.13) (V2H + V2h WhenL < S 2 L=25s _ (2H + Veh) (1.14) N N = Deviation angle (algebraic difference in grades) Ss = Sight Distance (m) (either SSD or OSD or ISD) H Height of eye level of driver above roadway surface (m) h = Height of subject above roadway surface (m) Note: 2 For SSD H = 1,20 mand h = 0.15 m hence (V2H + V2h) =44m 2 For OSDorISD = H = 1.20 mand h = 1.20 mhence (V2H + V2h) = 9.6m 1.7.3 Length of Valley Curve (L) A. Comfort Condition Nv? 0.5 L=2 | (1.15) Cc B. Head Light Sight Distance WhenL > S NS? ,=-—_—~ (1.16) (2h, + 2S tana) WhenL < S 2h, + 2S tana pao 2 ) (1.17) N N = Deviation angle (algebraic difference in grades) Ss = Head light sight Distance (m) (HSD = SSD) hy = Height of head lights above roadway surface (m) a = Inclination of head light beam with horizontal Note: hy = 0.75 m and a = 1° hence (2h, + 2S tana) = (1.5 + 0.035 S) 2.6 DESIGN CRITERIA The flexible pavements has been modeled as a three layer structure and stresses and strains at critical locations have been computed using the linear elastic model. To consider the aspects of performance, the following three types of pavement distress resulting from repeated (cyclic) application of traffic loads are considered: e Vertical compressive strain at the top of the sub-grade which can cause sub-grade deformation resulting in permanent deformation at the pavement surface. ¢ Horizontal tensile strain or stress at the bottom of the bituminous layer which can cause fracture of the bituminous layer. ¢ Pavement deformation within the bituminous layer. Binder Course Tensile Strain =, Granular Base / Sub Base Course ' Compre: Strain eee ee 4 C t oo Figure 2.1 : Critical Locations in Pavement While the permanent deformation within the bituminous layer can be controlled by meeting the mix design requirements, thickness of granular and bituminous layers are selected using the analytical design approach so that strains at the critical points are within the allowable limits. For calculating tensile strains at the bottom of the bituminous layer, the stiffness of dense bituminous macadam (DBM) layer with 60/70 bitumen has been used in the analysis. 2.7. FAILURE CRITERIA As shown in figure 2.11, A and B are the critical locations for tensile strains (et). Maximum value of the strain is adopted for design. C is the critical location for the vertical subgrade strain (€z) since the maximum value of the €, occurs mostly at C. Fatigue Criteria: Bituminous surfacing of pavements display flexural fatigue cracking if the tensile strain at the bottom of the bituminous layer is beyond certain limit. The relation between the fatigue life of the pavement and the tensile strain in the bottom of the bituminous layer is expressed as 12 3.89 0.854 Ny =2.21x107* (=) (=) (2.3) Ep E Ne Allowable number of load repetitions to produce 20% cracked surface area et Tensile strain at the bottom of surface layer (micro strain) E Elastic modulus of bituminous surfacing (MPa) Rutting Criteria: The allowable number of load repetitions to control permanent deformation can be expressed as 4.5337 N, = 4.1656 x 1078 (-) (2.4) Ez Nr Allowable number of load repetitions to produce rutting of 20 mm &z Vertical subgrade strain (micro strain) Standard axle load considered is 80 kN. One dual wheel set with a wheel load of 20kN, center-to-center tyre spacing of 310 mm and tyre pressure of 0.56 MPa is considered for analysis. 2.8 DESIGN CHARTS AND CATALOGUE Based on the performance of existing designs and using analytical approach, simple design charts (Figure 2.2 and 2.3) and a catalogue of pavement designs are added in the code. The pavement designs are given for subgrade CBR values ranging from 2% to 10% and design traffic ranging from 1 msa to 150 msa for an average annual pavement temperature of 35 C. The later thicknesses obtained from the analysis have been slightly modified to adapt the designs to stage construction. Using the following simple input parameters, appropriate designs could be chosen for the given traffic and soil strength: ¢ Design traffic in terms of cumulative number of standard axles; and © CBR value of subgrade. The designs relate to ten levels of design traffic 1, 2, 3, 4, 5, 10, 20, 30, 50, 100 and 150 msa. For intermediate traffic ranges, the pavement layer thickness may be interpolated linearly. For traffic exceeding 150 msa, the pavement design appropriate to 150 msa may be chosen and further strengthening carried out to extend the life at appropriate time based on pavement deflection measurements as per IRC: 81. 13 TOTAL THICKNESS OF PAVEMENT, mm 300) 800] ae Le | corse | L—] I 70 —— —— ~ ae E E La Lae [cms | 2 eo | | ——| pi ! = =, CBR. g Lae Ly | cans < Ja ——— e | __———“cBR a% | I 2 50 a CBR 9% | ———— o = eee 5 40 > z " OA | 300 P | | | 2009 SS 8 DESIGN TRAFFIC, msa Figure 2.2 : Pavement Thickness Design Chart for Traffic 1-10 msa 1000) CBR 2% 300 CERES L—| CBR 4% 800) ae |] | CBR 5% | CBR 6% we LT Ll] Le CBR. wo fe SS CBR 10% LT [4 ae | 400) | 20 «30 30 DESIGN TRAFFIC, msa 100 150 Figure 2.3 : Pavement Thickness Design Chart for Traffic 10-150 msa 14 Pavement Design Catalogue . Total PAVEMENT COMPOSITION (mm) Cumulative — ; " Pavement Bituminous Surfacing Traffic . - - Granular Granular Thickness Wearing Binder (msa) Base Sub-base (mm) Course Course (e129 1 375 20PC | ------ 225 150 2 425 20 PC 50 BM 225 150 3 450 20 PC 50 BM 250 150 5 475 25SDBC | 50DBM 250 150 10 550 40 BC 60 DBM 20 575 40 BC 85 DBM 30 590 40 BC 100 DBM 250 200 50 610 40 BC 120 DBM 100 640 50 BC 140 DBM 150 660 50 BC 160 DBM (eS 1 375 20PC | ------ 225 150 2 425 20 PC 50 BM 225 150 3 450 20 PC 50 BM 250 150 5 475 25 SDBC 50 DBM 250 150 10 540 40 BC 50 DBM 20 570 40 BC 80 DBM 30 585 40 BC 95 DBM 250 200 50 605 40 BC 115 DBM 100 635 50 BC 135 DBM 150 655 50 BC 155 DBM CBR 10% 1 375 20PC | ------ 225 150 2 425 20 PC 50 BM 225 150 3 450 20 PC 50 BM 250 150 5 475 25SDBC | 50DBM 250 150 10 540 40 BC 50 DBM 20 565 40 BC 75 DBM 30 580 40 BC 90 DBM 250 200 50 600 40 BC 110 DBM 100 630 50 BC 130 DBM 150 650 50 BC 150 DBM 2.9 PAVEMENT COMPOSITION Sub-base Course = Natural sand, gravel, laterite, brick metal, crushed stone or combinations thereof = Minimum CBR : = 20% upto 2 msa traffic = 30% exceeding 2 msa = Minimum Thickness = 150 mm for traffic < 10 msa = 200 mm for traffic 2 10 msa = If subgrade CBR < 2%, design for subgrade CBR of 2% and provide a 150 mm thick capping layer of minimum CBR 10% in addition to sub-base Base Course = Unbound granular material - WBM, WMM or other equivalent granular construction conforming to IRC/MORT&H specifications = Minimum Thickness = 225 mm for traffic < 2 msa = 250 mm for traffic > 2 msa = If WBM is used and traffic > 10 msa, minimum thickness is 300 mm (4 layers of 75 mm each) Bituminous Surfacing = Wearing course or Binder course+wearing course = Wearing course : Surface dressing, open-graded premix carpet, mix seal surfacing, SDBC and BC = Binder course : BM, DBM, mix seal surfacing, SDBC and BC = Wearing surface used is open-graded premix carpet of thickness upto 25 mm, it should not be counted towards the total thickness 2.10 FINAL REMARKS = The present guidelines follows mechanistic empirical approach and developed new set of designs up to 150 msa = Thickness charts are still available for CBR values of up to 10% only = Design charts are available for only a pavement temperature of 35° C = The contribution of individual component layers is still not realized fully with the system of catalogue thicknesses. The same can be done with the analytical tool for design. 18 3. ANALYSIS AND DESIGN OF RIGID PAVEMENTS 3.1 MODULUS OF SUBGRADE REACTION (K) x=? (3.4) A p Pressure sustained by a rigid plate of diameter 75 cm at design deflection A A Design deflection = 0.125 cm % Allowance for Worst Subgrade Moisture K,-K 2 (3.1b) us Pus Pressure required in the plate bearing test for design deflection of 0.125 cm which produces a deformation of 6 in unsoaked consolidation test Ps Pressure required to produce the same deformation 6 in the soaked consolidation test K Modulus of subgrade reaction for the prevailing moisture condition Ks Corrected modulus of subgrade reaction for worst subgrade moisture * Correction for Small Plate Size a K= K,— (3.1) a Ki Modulus of subgrade reaction determined using plate of radius a1 K Corrected modulus of subgrade reaction for standard plate of radius a 3.2 RADIUS OF RELATIVE STIFFNESS (1) Eh? “Ms (3.2) - axa — ral Modulus of elasticity of cement concrete Poisson's ratio of concrete = 0.15 Slab thickness Modulus of subgrade reaction zAzsEMm 3.3. EQUIVALENT RADIUS OF RESISTING SECTION (b) b= 1.6a? + h? — 0.675 h whena < 1.724h (3.3) b=a whena= 1.724h A Radius of wheel load distribution H Slab thickness 19 3(1+p)P Eh} 4u 1-p 1.18(1+2wWa = ——_ |In | —__ ] + 1.84 — = + = 4 3.6 Pe 34m | "| T00ka* 3 (3.68) 2 Ll 241.2 (0.76 + 0.4p)a Ae= P| |—3— |}}1-—_ 3.6h e a | (3.6 h) When p = 0.15 0.803P l a o6=—a— [+ log (=) + 0.666 @) - 0.034] (3.63) 0.431P a Ae= az [1 - 0.82 ()] (3.63) Gc, Oi, Ge Maximum stress at corner, interior and edge loading respectively Ac, Ai, Ae Maximum deflection at corner, interior and edge loading respectively h Slab thickness P Wheel load K Modulus of subgrade reaction a Radius of wheel load distribution | Radius of relative stiffness b Radius of resisting section c Side length of square contact area = 1.772a E Modulus of elasticity of cement concrete bh Poisson’s ratio of concrete = 0.15 3.5.4 Dual Tires 0.3 a 0.4L L 0.3 a ! ' --L-Ls> - > on 1 1 0.6L , Sy-O6L | OGL , Figure 3.2: Method for Converting Duals into a Circular Area 22 If Pu is the load on one tire and q is the contact pressure, the area of each tire is P. (3.7 a) 5227q ma? = 2(0.5227L7) + (Sq — 0.6L)L = 0.44541? + Sal (3.7 b) Pa 7" [z (0.3L)? + (0.4L)(0.6L)] = 0.52271? or L= The area of equivalent circle is The radius of contact area 0.8521P, S, P, os a= tt) (3.7.¢) qu mt \0.5227q 3.6 TEMPERATURE STRESSES 3.6.1 Warping Stresses (Westergaard Analysis) Interior Eatyje,+uc. oy EtG (8a) 2 1-u Edge C,Eat CyEat Ste =~ OF Ote = (3.8 b) Corner _ Eat a Ste = 34 —-mVI (3.8 c) Otc, Oti, Ste Maximum warping stress at corner, interior and edge region respectively a Radius of wheel load distribution | Radius of relative stiffness E Modulus of elasticity of cement concrete bh Poisson’s ratio of concrete = 0.15 a Thermal coefficient of concrete Cx, Cy, Bradbury warping stress coefficient 23 12 LA c LA c 10 1 0.000 7 1.030 3 08 2 2 0.040 8 1.077 o S 06 a 3 0.175 9 1.080 3 = o4 4 0.440 10 1.075 0.2 5 0.720 11 1.050 0 0 2 4 6 g 10 12 4 6 0.920 12 1.000 Values of L,/t and Ly/t Figure 3.3: Warping Stress Coefficient or Stress Correction Factor for Finite Slab (Bradbury — 1938 and IRC : 58-2002) 3.6.2 Frictional Stresses L ophB=Bzhycf Or L on = 5 Veh Ott Frictional Stress developed in cement concrete pavement h Slab Thickness B Slab width L Slab length f Coefficient of subgrade restraint (maximum value is about 1.5) Ve Unit weight of concrete (about 2400 kg/m?) (3.9 a) (3.9 b) 24 3.7.7 Characteristics of Concrete oe “* Modulus of Elasticity = Experimentally determined value = 3.0 x 10° kg/cm? for M40 Concrete * Poisson’s ratio w=0.15 “* Flexural strength of Cement Concrete f., = 45 kg/cm? for M40 Concrete * Coefficient of thermal expansion a= 10x 10° per °C oe oe a 3.7.8 Fatigue Behaviour of Cement Concrete N = Unlimited for SR <0.45 (3.11 a) N= ey when 0.45<SR<0.55 (3.116) R — 0.4325. logyoN = | for SR >0.55 (3.11¢) N Fatigue life SR Stress ratio Stress Ratio and Allowable Repetitions in Cement Concrete Stress Ratio Allowable Stress Ratio Allowable Stress Ratio Allowable Repetitions Repetitions Repetitions 0.45 62,790,761 0.59 40,842 0.73 832 0.46 14,335,236 0.60 30,927 0.74 630 0.47 5,202,474 0.61 23,419 0.75 477 0.48 2,402,754 0.62 17,733 0.76 361 0.49 1,286,914 0.63 13,428 0.77 274 0.50 762,043 0.64 10,168 0.78 207 0.51 485,184 0.65 7,700 0.79 157 0.52 326,334 0.66 5,830 0.80 119 0.53 229,127 0.67 4,415 0.81 90 0.54 166,533 0.68 3,343 0.82 68 0.55 124,526 0.69 2,532 0.83 52 0.56 94,065 0.70 1,917 0.84 39 0.57 71,229 0.71 1,452 0.85 30 0.58 53,937 0.72 1,099 -— oo 27 3.7.9 Stress Computations Edge Stress % Due to Load — Picket & Ray’s chart % Due to Temperature —Westergaard’s equation (Equation 2.7 b) Corner Stress %* Due to Load —Westergaard’s analysis modified by Kelly (Equation 2.3 c) % Due to temperature — negligible and hence ignored 3.7.10Temperature Differential Recommended Temperature Differentials for Concrete Zone States Temperature Differential, °C in slab of thickness 15 cm | 20 cm | 25cm} 30 cm | Punjab, U.P., Uttaranchal, Gujarat. 12.5 | 13.1 | 14.3 | 15.8 Rajasthan, Haryana and North M.P. Excluding hilly regions. Il Binar, Jharkhand, West Bengal, Assam | 15.6 | 16.4 | 16.6 | 16.8 and Eastern Orissa excluding hilly regions and coastal areas Il Maharashtra, Karnataka, South M.P., 17.3 | 19.0 | 20.3 | 21.0 Chattisgarh, Andhra Pradesh, Western Orissa and North Tamil Nadu, excluding hilly regions and coastal areas IV Kerala and South Tamilnadu excluding | 15.0 | 16.4 | 17.6 | 18.1 hilly regions and coastal areas Vv Coastal areas bounded by hills 14.6 | 15.8 | 16.2 | 17.0 Vi Coastal areas unbounded by hills 15.5 | 17.0 | 19.0 | 19.2 3.7.11Recommended Design Procedure for Slab Thickness % Stipulate design values for the various parameters “% Decide types and spacing between joints Select a trial design thickness of pavement “ Compute the repetitions of axle loads of different magnitudes during design period “ Calculate cumulative fatigue damage (CFD) “If CFD is more than 1.0 revise the thickness % =Check for load+temperature stress at edge with modulus of rupture “Check for corner stress 28 3.8 Design of Joints Expansion Joint If &' is the maximum expansion in a slab of length Le with a temperature rise from T1 to T2, then 5' = Le a (Ti to T2) where ais the coefficient of thermal expansion of concrete. Expansion joint gap 6 = 2 6' Maximum expansion joint gap = 25 mm Maximum Spacing between expansion joints for rough interface layer 140m —all slab thicknesses for smooth interface layer when pavement is constructed in summer 90m — upto 200 mm thick slab 120m — upto 250 mm thick slab when pavement is constructed in winter 50m — upto 200 mm thick slab 60m — upto 250 mm thick slab Contraction Joint Le OchB=B>hycf (3.12) Otc Allowable tensile stress in concrete h Slab thickness B Slab width Le Slab length or spacing b/w contraction joints Ve Unit weight of concrete f Coefficient of subgrade restraint (max 1.5) If Reinforcement is provided, replace LHS by ots As Maximum Spacing between contraction joints for unreinforced slabs 4.5m —all slab thicknesses for reinforced slabs 13m — for 150 mm thick slab 14m — for 200 mm thick slab 29 m Lv] (9) m _ o > SSS CL AN K Slab Thickness (mm) kg/cm? | a6 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 SINGLE AXLE LOAD 6.0 22.490 | 18.824 | 16.054 | 13.902 | 12.191 | 10.802 | 9.656 | 8.698 | 7.886 | 7.191 | 6.590 8.0 21.457 | 17.961 | 15.319 | 13.264 | 11.631 | 10.307 | 9.215 | 8.302 | 7.529 | 6.868 | 6.297 10.0 20.684 | 17.319 | 14.771 | 12.790 | 11.215 | 9.938 | 8.886 | 8.006 | 7.252 | 6.625 | 6.075 15.0 19.331 | 16.203 | 13.824 | 11.972 | 10.497 | 9.301 | 8.317 | 7.494 | 6.798 | 6.203 | 5.689 30.0 17.131 | 14.410 | 12.322 | 10.684 | 9.373 | 8.307 | 7.427 | 6.692 | 6.070 | 5.539 | 5.081 Single Axle Load — 8 tons 6.0 28.615 | 24.000 | 20.502 | 17.779 | 15.610 | 13.849 | 12.396 | 11.179 | 10.148 | 9.264 | 8.500 8.0 27.246 | 22.862 | 19.533 | 16.939 | 14.872 | 13.195 | 11.811 | 10.653 | 9.672 | 8.832 | 8.106 10.0 26.216 | 22.012 | 18.812 | 16.315 | 14.325 | 12.709 | 11.376 | 10.261 | 9.317 | 8.509 | 7.810 15.0 24.405 | 20.527 | 17.560 | 15.236 | 13.379 | 11.870 | 10.626 | 9.584 | 8.702 | 7.948 | 7.297 30.0 21.450 | 18.122 | 15.553 | 13.524 | 11.892 | 10.559 | 9.454 | 8.529 | 7.744 | 7.073 | 60494 Single Axle Load — 10 tons 6.0 34.471 | 28.971 | 24.785 | 21.519 | 18.912 | 16.794 | 15.044 | 13.578 | 12.335 | 11.269 | 10.347 8.0 32.755 | 27.552 | 23.583 | 20.478 | 17.999 | 15.983 | 14.319 | 12.925 | 11.743 | 10.731 | 9.855 10.0 31.461 | 26.488 | 22.684 | 19.703 | 17.320 | 15.381 | 13.780 | 12.439 | 11.302 | 10.329 | 9.487 15.0 29.184 | 24.623 | 21.117 | 18.358 | 16.146 | 14.342 | 12.851 | 11.601 | 10.541 | 9.634 | 8.851 30.0 25.492 | 21.604 | 18.594 | 16.210 | 14.284 | 12.706 | 11.394 | 10.291 | 9.354 | 8.550 | 7.856 Single Axle Load — 12 tons 6.0 40.103 | 33.774 | 28.939 | 25.153 | 22.126 | 19.662 | 17.625 | 15.917 | 14.467 | 13.225 | 12.150 8.0 38.034 | 32.067 | 27.496 | 23.909 | 21.037 | 18.697 | 16.761 | 15.138 | 13.762 | 12.582 | 11.562 10.0 36.475 | 30.785 | 26.415 | 22.980 | 20.225 | 17.978 | 16.119 | 14.559 | 13.237 | 12.103 | 11.123 15.0 33.739 | 28.537 | 24.527 | 21.363 | 18.817 | 16.736 | 15.010 | 13.561 | 12.330 | 11.276 | 10.364 30.0 29.329 | 24.918 | 21.493 | 18.774 | 16.575 | 14.767 | 13.261 | 11.992 | 10.911 | 9.982 | 9.178 Single Axle Load — 14 tons 6.0 45.547 | 38.432 | 32.979 | 28.697 | 25.267 | 22.469 | 20.152 | 18.208 | 16.558 | 15.142 | 13.917 8.0 43.126 | 36.434 | 31.293 | 27.247 | 23.999 | 21.347 | 19.150 | 17.306 | 15.740 | 14.397 | 13.235 10.0 41.306 | 34.933 | 30.028 | 26.161 | 23.053 | 20.511 | 18.404 | 16.634 | 15.131 | 13.841 | 12.725 15.0 38.121 | 32.307 | 27.817 | 24.264 | 21.407 | 19.061 | 17.112 | 15.472 | 14.078 | 12.881 | 11.845 30.0 32.998 | 28.101 | 24.281 | 21.243 | 18.783 | 16.757 | 15.067 | 13.640 | 12.423 | 11.375 | 10.466 Single Axle Load — 16 tons 6.0 50.833 | 42.964 | 36.921 | 32.164 | 28.344 | 25.223 | 22.635 | 20.461 | 18.614 | 17.029 | 15.656 8.0 48.065 | 40.675 | 34.988 | 30.503 | 26.895 | 23.944 | 21.493 | 19.434 | 17.684 | 16.181 | 14.880 10.0 45.989 | 38.957 | 33.538 | 29.259 | 25.812 | 22.988 | 20.642 | 18.668 | 16.990 | 15.549 | 14.301 15.0 42.365 | 35.961 | 31.009 | 27.090 | 23.925 | 21.328 | 19.165 | 17.342 | 15.790 | 14.456 | 13.299 30.0 36.521 | 31.173 | 26.981 | 23.637 | 20.923 | 18.688 | 16.822 | 15.244 | 13.896 | 12.734 | 11.724 Single Axle Load — 18 tons 6.0 55.986 | 47.388 | 40.775 | 35.560 | 31.364 | 27.930 | 25.079 | 22.680 | 20.641 | 18.889 | 17.371 8.0 52.878 | 44.810 | 38.595 | 33.687 | 29.732 | 26.491 | 23.796 | 21.528 | 19.598 | 17.939 | 16.502 10.0 50.552 | 42.879 | 36.962 | 32.284 | 28.511 | 25.414 | 22.838 | 20.668 | 18.820 | 17.231 | 15.853 15.0 46.488 | 39.520 | 34.120 | 29.841 | 26.383 | 23.542 | 21.173 | 19.174 | 17.470 | 16.003 | 14.729 30.0 39.915 | 34.147 | 29.604 | 25.996 | 23.009 | 20.570 | 18.532 | 16.808 | 15.334 | 14.062 | 12.956 32 m Lv] (9) m _ o > SSS CL AN (kg, K Slab Thickness (mm) kg/em3 | 16 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 SINGLE AXLE LOAD 6.0 61.027 | 51.719 | 44.552 | 38.894 | 34.333 | 30.595 | 27.486 | 24.869 | 22.642 | 20.726 | 19.066 8.0 57.585 | 48.856 | 42.126 | 36.807 | 32.516 | 28.994 | 26.062 | 23.591 | 21.485 | 19.674 | 18.104 10.0 55.008 | 46.716 | 40.312 | 35.246 | 31.155 | 27.795 | 24.996 | 22.634 | 20.621 | 18.888 | 17.385 15.0 50.503 | 42.996 | 37.162 | 32.532 | 28.789 | 25.710 | 23.142 | 20.972 | 19.120 | 17.524 | 16.137 30.0 43.199 | 37.031 | 32.157 | 28.241 | 25.048 | 22.411 | 20.206 | 18.339 | 16.742 | 15.364 | 14.164 Single Axle Load — 22 tons 6.0 65.973 | 55.968 | 48.260 | 42.168 | 37.254 | 33.220 | 29.862 | 27.030 | 24.618 | 22.543 | 20.743 8.0 62.198 | 52.825 | 45.592 | 39.871 | 35.251 | 31.456 | 28.293 | 25.623 | 23.348 | 21.388 | 19.686 10.0 59.370 | 50.478 | 43.599 | 38.152 | 33.752 | 30.135 | 27.119 | 24.571 | 22.396 | 20.524 | 18.897 15.0 54.418 | 46.397 | 40.143 | 35.172 | 31.149 | 27.839 | 25.075 | 22.739 | 20.743 | 19.021 | 17.524 30.0 46.389 | 39.836 | 34.646 | 30.464 | 27.045 | 24.216 | 21.847 | 19.841 | 18.124 | 16.642 | 15.350 Single Axle Load — 24 tons 6.0 70.833 | 60.147 | 51.908 | 45.392 | 40.131 | 35.809 | 32.206 | 29.165 | 26.573 | 24.341 | 22.402 8.0 66.726 | 56.727 | 48.999 | 42.884 | 37.943 | 33.881 | 30.492 | 27.630 | 25.187 | 23.082 | 21.252 10.0 63.645 | 54.174 | 46.830 | 41.011 | 36.307 | 32.438 | 29.209 | 26.480 | 24.149 | 22.139 | 20.391 15.0 58.243 | 49.729 | 43.071 | 37.768 | 33.470 | 29.932 | 26.978 | 24.479 | 22.342 | 20.498 | 18.892 30.0 49.497 | 42.573 | 37.077 | 32.640 | 29.004 | 25.990 | 23.461 | 21.318 | 19.484 | 17.898 | 16.517 TANDEM AXLE LOAD Tandem Axle Load — 12 tons 6.0 18.268 | 15.392 | 13.278 | 11.666 | 10.398 | 9.368 | 8.523 | 7.810 | 7.201 | 6.674 | 6.215 8.0 17.422 | 14.600 | 12.535 | 10.970 | 9.746 | 8.763 | 7.953 | 7.282 | 6.706 | 6.215 | 5.783 10.0 16.839 | 14.056 | 12.023 | 10.486 | 9.290 | 8.336 | 7.554 | 6.902 | 6.355 | 5.881 | 5.473 15.0 15.915 | 13.204 | 11.222 | 9.728 | 8.571 | 7.653 | 6.907 | 6.293 | 5.777 | 5.336 | 4.958 30.0 14.597 | 12.040 | 10.154 | 8.724 | 7.617 | 6.742 | 6.038 | 5.461 | 4.981 | 4.578 | 4.233 Tandem Axle Load — 16 tons 6.0 22.993 | 19.429 | 16.805 | 14.801 | 13.223 | 11.942 | 10.888 | 9.998 | 9.238 | 8.577 | 8.002 8.0 21.873 | 18.385 | 15.827 | 13.883 | 12.362 | 11.139 | 10.133 | 9.295 | 8.576 | 7.964 | 7.422 10.0 21.096 | 17.667 | 15.154 | 13.248 | 11.762 | 10.574 | 9.603 | 8.792 | 8.109 | 7.518 | 7.009 15.0 19.854 | 16.533 | 14.094 | 12.248 | 10.814 | 9.675 | 8.750 | 7.986 | 7.344 | 6.795 | 6.324 30.0 18.075 | 14.965 | 12.663 | 10.914 | 9.553 | 8.474 | 7.603 | 6.889 | 6.295 | 5.793 | 5.365 Tandem Axle Load — 20 tons 6.0 27.452 | 23.265 | 20.171 | 17.802 | 15.932 | 14.416 | 13.162 | 12.105 | 11.200 | 10.413 | 9.727 8.0 26.046 | 21.963 | 18.957 | 16.664 | 14.864 | 13.417 | 12.226 | 11.230 | 10.378 | 9.648 | 9.004 10.0 25.067 | 21.064 | 18.118 | 15.876 | 14.122 | 12.717 | 11.567 | 10.606 | 9.795 | 9.093 | 8.488 15.0 23.499 | 19.636 | 16.790 | 14.628 | 12.943 | 11.602 | 10.511 | 9.605 | 8.845 | 8.196 | 7.636 30.0 21.275 | 17.661 | 14.985 | 12.951 | 11.365 | 10.104 | 9.083 | 8.244 | 7.545 | 6.952 | 6.447 33 m Lv] (9) m _ o > SSS CL AN K Slab Thickness (mm) kg/em? | 16 [| 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 TANDEM AXLE LOAD 6.0 31.690 | 26.936 | 23.409 | 20.698 | 18.554 | 16.814 | 15.371 | 14.153 | 13.108 | 12.201 | 11.408 8.0 29.991 | 25.369 | 21.953 | 19.339 | 17.280 | 15.622 | 14.255 | 13.108 | 12.127 | 11.284 | 10.543 10.0 28.810 | 24.284 | 20.943 | 18.394 | 16.394 | 14.785 | 13.467 | 12.365 | 11.431 | 10.685 | 9.926 15.0 26.924 | 22.558 | 19.341 | 16.893 | 14.979 | 13.451 | 12.206 | 11.170 | 10.298 | 9.553 | 8.909 30.0 24.271 | 20.190 | 17.166 | 14.868 | 13.076 | 11.649 | 10.492 | 9.539 | 8.743 | 8.067 | 7.490 Tandem Axle Load — 28 tons 6.0 35.744 | 30.465 | 26.537 | 23.508 | 21.105 | 19.153 | 17.528 | 16.155 | 14.977 | 13.952 | 13.054 8.0 33.752 | 28.630 | 24.834 | 21.922 | 19.623 | 17.765 | 16.232 | 14.940 | 13.838 | 12.885 | 12.050 10.0 32.372 | 27.357 | 23.651 | 20.818 | 18.589 | 16.791 | 15.315 | 14.079 | 13.027 | 12.121 | 11.331 15.0 30.179 | 25.339 | 21.773 | 19.060 | 16.935 | 15.235 | 13.815 | 12.687 | 11.711 | 10.875 | 10.150 30.0 27.100 | 22.588 | 19.239 | 16.691 | 14.705 | 13.124 | 11.841 | 10.782 | 9.897 | 9.144 | 8.499 Tandem Axle Load — 32 tons 6.0 39.642 | 33.871 | 29.569 | 26.242 | 23.595 | 21.439 | 19.641 | 18.119 | 16.811 | 15.672 | 14.673 8.0 37.364 | 31.768 | 27.616 | 24.427 | 21.902 | 19.856 | 18.163 | 16.734 | 15.515 | 14.457 | 13.530 10.0 35.790 | 30.309 | 26.258 | 23.159 | 20.717 | 18.743 | 17.117 | 15.754 | 14.589 | 13.587 | 12.710 15.0 33.296 | 28.006 | 24.109 | 21.144 | 18.822 | 16.960 | 15.438 | 14.164 | 13.089 | 12.167 | 11.365 30.0 29.783 | 24.877 | 21.224 | 18.438 | 16.288 | 14.541 | 13.139 | 11.981 | 11.012 | 10.188 | 9.480 Tandem Axle Load — 36 tons 6.0 43.411 | 37.172 | 32.515 | 28.908 | 26.030 | 23.680 | 21.717 | 20.051 | 18.617 | 17.368 | 16.268 8.0 40.852 | 34.801 | 30.312 | 26.860 | 24.123 | 21.899 | 20.056 | 18.495 | 17.163 | 16.003 | 14.987 10.0 39.089 | 33.161 | 28.781 | 25.429 | 22.785 | 20.645 | 18.878 | 17.394 | 16.123 | 15.028 | 14.067 15.0 36.294 | 30.579 | 26.365 | 23.160 | 20.649 | 18.634 | 16.983 | 15.604 | 14.435 | 13.431 | 12.557 30.0 32.339 | 27.069 | 23.132 | 20.123 | 17.777 | 15.909 | 14.394 | 13.143 | 12.093 | 11.202 | 10.434 Tandem Axle Load — 40 tons 6.0 47.070 | 40.381 | 35.385 | 31.513 | 28.415 | 25.881 | 23.757 | 21.953 | 20.398 | 19.041 | 17.843 8.0 44.237 | 37.747 | 32.934 | 29.231 | 26.292 | 23.899 | 21.912 | 20.226 | 18.785 | 17.526 | 16.425 10.0 42.285 | 35.929 | 31.232 | 27.638 | 24.802 | 22.504 | 20.602 | 19.002 | 17.629 | 16.445 | 15.403 15.0 39.185 | 33.071 | 28.555 | 25.117 | 22.425 | 20.264 | 18.492 | 17.011 | 15.753 | 14.671 | 13.727 30.0 34.785 | 29.172 | 24.972 | 21.754 | 19.240 | 17.237 | 15.613 | 14.271 | 13.145 | 12.189 | 11.365 Tare Citas AO ete nO 6.0 48.864 | 41.955 | 36.795 | 32.793 | 29.590 | 26.966 | 24.766 | 22.894 | 21.279 | 19.870 | 18.624 8.0 45.894 | 39.191 | 34.220 | 30.396 | 27.359 | 24.884 | 22.828 | 21.081 | 19.587 | 18.280 | 17.137 10.0 43.848 | 37.285 | 32.434 | 28.721 | 25.792 | 23.418 | 21.451 | 19.795 | 18.373 | 17.146 | 16.065 15.0 40.593 | 34.290 | 29.626 | 26.076 | 23.297 | 21.065 | 19.233 | 17.703 | 16.402 | 15.282 | 14.305 30.0 35.972 | 30.194 | 25.868 | 22.550 | 19.956 | 17.888 | 16.210 | 14.825 | 13.662 | 12.675 | 11.823 Tandem Axle Load — 44 tons 6.0 50.636 | 43.511 | 38.189 | 34.061 | 30.754 | 28.041 | 25.767 | 23.829 | 22.156 | 20.694 | 19.401 8.0 47.531 | 40.618 | 35.491 | 31.547 | 28.415 | 25.860 | 23.735 | 21.929 | 20.383 | 19.030 | 17.845 10.0 45.388 | 38.624 | 33.622 | 29.793 | 26.772 | 24.323 | 22.292 | 20.581 | 19.111 | 17.841 | 16.721 15.0 41.978 | 35.490 | 30.685 | 27.024 | 24.157 | 21.856 | 19.966 | 18.388 | 17.045 | 15.888 | 14.878 30.0 37.137 | 31.197 | 26.748 | 23.335 | 20.662 | 18.531 | 16.801 | 15.371 | 14.172 | 13.154 | 12.275 34