In Joint Venture Venture
f o r a l l m y p r e s en e n t a t i o n s , p l e as as e v i s i t http://aproadbuildqa.blogspot.com
Important Publications for Rural Roads 1.Specifications for Rural Roads, MORD 1.Specifications (2004). 2.Rural Roads Manual IRC:SP:20-2002. 3. MORD Quality Assurance Assurance Handbook for Rural Roads Volume I and II :2007 4.Hill Road Manual: IRC:SP:48-1998. 5.IRC:SP: 72-2007: Guidelines for design of flexible pavements for low volume Rural Roads 6. IRC:SP: 62-2004 Guidelines for Design of Rigid Pavements for Rural Roads
ADVANTAGES OF CONCRETE ROADS Long Life Practically Maintenance-Free Performance Good Riding Quality Good Abrasion Resistance Withstand Extremes of Weather Exclusion of Water Effect of oil Spillage Avoided Skid Resistant Used in Areas where soils have Poor Engineering Properties Design Precision Pollution –Free Construction Good Foundation for Strengthening Fuel Saving Economy in Life-Cycle Cost 4
Different Pavement Types
Asphalt Section
Concrete Section
Asphalt Layer Subbase
Base
Subgrade
Subbase Subgrade
Rigid Pavement
Flexible Pavement 5
How Pavements Carry Loads
3000 kg.
3000 kg.
Asphalt Layer pressure < 0.2 MPa pressure 2.0 MPa
Concrete’s Rigidness spreads the load over a large area and keeps pressures on the sub-grade low. 7
DISADVANTAGES OF CONCRETE ROADS
Problems of Underground Utilities
Do not Permit Stage Construction
Energy Content of Concrete Pavements is high 8
Design Guidelines of IRC:58 are applicable for roads having a daily commercial traffic (vehicles with laden weight more than 3t) over 150 Design guidelines contained in IRC:SP:62-2004 are applicable only for low volume rural roads. It is also applicable for conventional screedcompacted pavements and roller compacted concrete pavements.
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Sub base for Rural Roads as per IRC:SP:622004 1) It provides an uniform and reasonably firm support 2) It prevents mud-pumping on sub-grade of clays and silts 3) It acts as a levelling course on distorted, non-uniform and undulating sub-grade 4) It acts as a capillary cut-off
Thickness of sub-base 1)For a designed wheel load of 51 kN, 150mm thick WBM or GSB may be provided 2) For a designed wheel load of 30 kN, 75mm thick WBM or GSB may be provided. Note: When the above type of sub-base is provided, effective k value may be taken as 20% more than k value of the sub-grade. A plastic sheet of 125 micron thick shall be provided over the sub-base to act as a separation layer between the sub-base and concrete slab.
Recommended Temperature Differentials for Concrete Slabs as per IRC: SP:62-2004
Zone
Stages
Temperature Differential, ºC in Slabs of Thickness
15 cm
20 cm
25 cm
30 cm
1
Punjab, U.P. Rajasthan, Haryana and North M.P. excluding hilly regions and coastal areas
12.5
13.1
14.3
15.8
2
Bihar, West Bengal Assam and Eastern Orrisa excluding hilly regions and coastal areas
15.6
16.4
16.6
16.8
3
Maharashtra, Karnataka, South M.P., Andhra Pradesh, Western Orissa and North Tamil Nadu excluding hilly regions and coastal areas
17.3
19.0
20.3
21.0
4
Kerala and South Tamil Nadu excluding hilly regions and coastal areas
15.0
16.4
17.6
18.1
5
Coastal areas bounded by hills
14.6
15.8
16.2
17.0
15.5
17.0
19.0
19.2
Curling and warping of slabs
The solution to cracking is not necessarily to focus on increasing concrete strength. Design strength must be balanced with other factors that affect cracking, such as volume changes, curling and warping, loading, 13 weather and level of support
TABLE 5 : CONCRETE PAVEMENT THICKNESS FOR RURAL ROADS as per IRC:SP 62-2004 Pavement Thickness(mm) Low Traffic Heavy Traffic (Wheel Load-30 kN) (Wheel Load-51kN) Concrete grade
Zone-I
< 15o
Zone-II, Zone-II, Zone-III Zone-I IV,V,VI IV,V,VI Temperature Differential oC o to 15.1o to 17. 1o to 15.1 <15o o o 17 20 17o
Zone-III 17. 1o to 20o
30
150
160
170
190
190
200
35
150
150
160
180
180
190
40
150
150
150
170
180
180
Note: 1) maximum temperature is considered in the computation. 2) design thickness values are based on the 90-day strength. CBR =4%, E=3.0X104 MPa, µ (Poisson’s ratio)=0.15, Tyre Pressure=0.50MPa(For wheel load 30kN), 0.7MPa (for wheel load 51 kN), Configuration of slab=3.75m x 3.75m
Cem ents th at can b e us ed as p er IRC: 44-2008
A n y o f t h e f o l lo w i n g t y p es o f c em en t s c ap a b l e o f ac h i e v in g t h e d es i g n s t r en g t h an d d u r a b i li t y m ay b e u s ed w i t h t h e p r i o r a p p r o v a l o f t h e En g i n e er. 1. O r d i n ar y P o r t l an d C em en t , 33 g r ad e , IS : 269 2. O r d i n a r y P o r t l an d C em en t , 43 g r ad e , IS : 8 112 3. O r d i n a r y Po r t l a n d C em en t , 53 g r a d e , IS : 1 22 69 4. Po r t l an d P o zzal o n a C em en t (f l y as h b a s ed , IS: 1489, p art1 5. Po r t lan d Sl ag Cem en t , IS: 455
Physical characteristic requirement of cement Requirements 33 grade
43 grad e
53 grade
IS: 269-1989
IS: 8 112- 1989
Is: 12269-1987
3 days
16
23
27
7 days
22
33
37
28 day s
33
43
53
225
225
225
Initial – ( m i n i m u m )
30
30
30
Final – ( m a x i m u m )
600
600
600
10
10
10
Characteristic
M in i m u m c o m p r es s i v e 2 s t r e n g t h i n N /m m
2 F i n en e s s (m i n i m u m ) (M /K g )
S et t i n g t i m e (m i n u t e s )
Soundness, expansion Le Ch atleier – (m a x im u m ) m m
MORD Table 1500.1: Combined Gradation of Coarse and fine aggregates for CC roads
IS Sieve Size
Percent by Weight Passing the Sieve
26.5mm
100
19 mm
80-100
9.5 mm
55-80
4.75 mm
35-60
0.600mm
10-35
0.075mm
0-8
Fine Aggregate as per Table 4 0f IS: 383 Applicable for CC roads and Buildings. Percent passing for
IS Sieve Designation
Grading
Grading
Grading
Grading
Zone-I
Zone-II
Zone-III
Zone-IV
10mm
100
100
100
100
4.75mm
90 – 100
90 – 100
90 – 100
95 – 100
2.36mm
60 – 95
75 – 100
85 – 100
95 – 100
1.18mm
30 – 70
55 – 90
75 – 100
90 – 100
600microns
15 – 34
35 – 59
60 – 79
80 – 100
300microns
5 – 20
8 – 30
12 – 40
15 – 50
150microns
0 – 10
0 – 10
0 – 10
0 - 15
Zone IV is not allowable for RCC works and CD works as per MORT&H and MORD Specifications
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Zone-I sand FM=3.32
Zone-II sand F M =3.08
Fine aggregate as per IS:383 that can be used in Plain Cement Concrete roads
Zone-III sand. F.M =2.75
Zone-IV sand FM=2.24 19
Requirements of coarse (graded size) aggregate as per table 2 of IS: 383 (MORD table 800.1 or MORT&H 1000-1) Percent by Weight Passing the Sieve
IS Sieve Size
40 mm
20 mm
12.5 mm
63 mm
100
--
--
40 mm
95-100
100
--
20 mm
30-70
95-100
100
12.5 mm
--
--
90-100
10 mm
10-35
25-55
40-85
4.75 mm
0-5
0-10
0-10
Single size aggregates shall not be used for any Concrete item unless specified
Maximum size of Coarse aggregate may be as large as possible within the limits specified, but in no case greater than ¼th of minimum thickness of member or 10mm less than the clear distance between individual reinforcement or 10mm less than clear cover to any reinforcement. 20
Requirements of fine Aggregate as per Table 1000-2 of MORT&H or table 4 of IS: 383 IS Sieve Designation
Percent passing for Grading Zone-I
Grading Zone-II
Grading Zone-III
10mm
100
100
100
4.75mm
90 – 100
90 – 100
90 – 100
2.36mm
60 – 95
75 – 100
85 – 100
1.18mm
30 – 70
55 – 90
75 – 100
600microns
15 – 34
35 – 59
60 – 79
300microns
5 – 20
8 – 30
12 – 40
150microns
0 – 10
0 – 10
0 – 10
I
II
Clay lumps ≤ 4%, Coal and lignite ≤ 1% Material passing 75 micron IS sieve ≤ 15% in case of crushed sand
III
Water for mixing and curing as per IS:456 and IS:3025 Potable water (pH value 6 to 8) is generally considered satisfactory for both mixing and curing. pH value shall not be less than 6 Permissible limits for solids in Water Cl. 5.4 of IS: 456-2000 Tested as per
Permissible limt maximum
Organic
IS 3025 part 18
200 mg/l
Inorganic
IS 3025 part 18
3000 mg/l
Sulphate as SO3
IS 3025 part 24
400 mg/l
Chloride as cl
IS 3025 part 32
Suspended matter
IS 3025 part 18
2000 mg/l for PCC 500 mg/l for RCC 2000 mg/l
Function of Plasticizers (Admixtures conforming to IS:6925 and IS:9103 may be used up to 2% by weight as per IS:456) Fine cement particles being very small clump together and flocculate when water is added to concrete. This ionic attraction between the particles trap considerable volume of water and hence water required for workability of concrete mix is not fully utilised. Negative charges are induced on the fine cement particles causing flocks to disperse and release the entrapped water. Water reducing admixtures or plasticizers therefore help to increase the flow of the concrete mix considerably.
Dispersion of entrapped air with the addition of plasticizer
Coefficient of Permeability for different W/C ratios S.No
W/C ratio
Coefficient of Permeability
1
0.35
1.05 x 10-3
2
0.50
10.30 x 10 -3
3
0.65
1000 x 10-3
Placing of concrete Concrete shall be deposited on the sub base to the required depth and width in successive batches and in continuous operation. Care shall be taken to see that no segregation takes place. Spreading shall be as uniform as possible and shall be accompanied by shovels. While being placed, the concrete shall be rodded with suitable tools so that formation of voids or honeycomb pockets are avoided.
MORD 1501.13 concreting in hot weather No concreting shall be done when the concrete temperature is above 30°C measured at point of placing and or when ambient temperature is above 35°C. In adverse conditions, like high temperature, low relative humidity, excessive wind velocity, imminence of rains etc. freshly laid concrete shall be adequately protected by tarpaulins.
MORD 1501.14: Concreting in cold weather No concreting shall be done when the concrete temperature is below 5°C
Compaction of Concrete Compaction is necessary to remove entrapped air present in concrete after it is mixed, transported and placed. Compaction also eliminates stone pockets and remove all types of voids. Consolidation is the process of making the freshly placed PCC into a more uniform and compact mass by eliminating undesirable air voids and causing it to move around potential obstructions. Vibrators work by rotating an eccentric weight which causes the entire vibrator to move back and forth. This movement excites particles within the PCC mass, causing them to move closer together and better flow around obstructions. On vibration, concrete mix gets fluidized resulting in entrapped air raising to the surface and concrete becoming denser
Guidelines for compaction with Pin Vibrator 1) Insert poker quickly and allow it to penetrate by its own weight to the bottom of layer so that the entrapped air is removed uniformly. 2) Leave the poker in concrete for 10 seconds. Compaction time depends on slump. 3) Poker must be inserted quickly, but withdrawal must be slow so that the hole left by the poker is filled up as it is being withdrawn. 4) Locations of poker insertion should be staggered. 5) Avoid touching the form work (and reinforcement) with poker. 6) Poker should extend up to 100mm into the previous layer.
MORD 1501.17: Texturing Just before the concrete becomes non plastic, the surface shall be textured with an approved long handled steel or fiber brush. The brush shall be pulled gently over the pavement surface transversely from one edge to the other. Adjacent strokes shall be slightly overlapped. Texturing shall be perpendicular to the center line of the pavement. The corrugations so produced will be uniform in character, width and about 1.5mm deep. Texturing shall be completed before the concrete reaches such a stage that the surface is likely to be torn or unduly roughened by the operation. Texturing shall be free from porous or rough spots, irregularities, depressions and small pockets.
TPQA Inspection of Madnur ZP Road to Bapuji Yanadi Colony. Checking the width of C.C Road with texture.
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TPQA Inspection of Madnur ZP Road to Peddapattupalem C.C Road with texture.
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Concrete Curing Curing is the process of maintaining a satisfactory moisture content and favorable temperature in the concrete during hydration of cementetious material so that the desired properties of the concrete are developed. Its objective is specifically to keep the concrete saturated until the water filled spaces in the fresh cement paste are filled to the desired extent by products of the hydration.
Water evaporation from concrete surface Continuous water supply
MORD 15001.18: Curing After finishing, the pavement surface shall be entirely covered with wet hessian cloth (minimum of 2 layers), burlap or jute mats. The coverings used shall be of such size that when laid, will extend by 500mm beyond the slabs. They shall be placed as soon as the concrete has set sufficiently to prevent marring of the surface. They shall be maintained fully wetted for 24 hours. The concrete slab shall not be exposed for more than 30 minutes for saw cutting of joints. After saw cutting of joints, it shall be covered and kept wet. Upon the removal of wet covers after 24 hours, the slabs shall be thoroughly wetted and then cured by ponding. Exposed edges shall be banked with substantial amount of earth.
Effects of Improper Curing Lowering
of compressive and flexural strengths
Sanding
and dusting of surface and lower abrasion resistance
Higher
permeability and lower durability
Cracks
due to plastic shrinkage, drying shrinkage and thermal cracking
Increased Lower
rate of Carbonation and chloride ingress
weathering and frost resistance
TPQA Inspection of R&B Road to Pinnivaripalem- C.C Road Curing by ponding.
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Surface due to ineffective curing before ponding
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam dist. On 15.05.2013. Cube casting.
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam dist. On 15.05.2013. Slump checking.
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 15.05.2013. Slump checking.
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 15.05.2013. Material gradation checking.
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 15.05.2013. Temperature checking.
TPQA-NCRMP inspection of Road from R&B road to Revupolavaram Cyclone shelter in Visakhapatnam district on 26.03.2013. Gunny rolls used for primary curing.
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TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 15.05.2013. Coconut cover waste for secondary curing
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam dist. On 25.05.2013. secondary curing
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 25.05.2013.
TPQA-NCRMP inspection of Kothapatnam RCS in Visakhapatnam district on 25.05.2013. Dowel bars
TPQA Inspection of KEM R&B Road to E.Pallepalem. Concreting in progress.
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Leveling or finishing of C.C surface.
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Leveling or finishing of C.C surface.
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Checking the width of C.C Road.
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Checking the thickness of C.C Road
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Compaction of oncrete.
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TPQA Inspection of KEM R&B Road to E.Pallepalem – Compaction of C.C Road.
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TPQA Inspection of KEM R&B Road to E.Pallepalem –
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MORD 1501.7 Sep aration m em b rane A s e p a r at i o n m e m b r a n e s h al l b e u s e d b e t w e en t h e concrete slab and sub-base. It shall be i m p r e g n a b l e p l a s t i c s h e et 1 25 m i c r o n s t h i c k l ai d w i t h o u t c r e a s es . B e fo r e p l ac i n g i t , t h e s u b - b a s e s h a ll b e s w e p t c l e an o f al l ex t r a n e o u s m a t er i a l s MORD 1501.8.1 Fo rm ation Of Jo in ts Saw cutting of joints of pavement slab as per stipulated dimensions should be done when c o n c r e te is n e i t h e r to o s o f t n o r t o o h a r d . S aw i n g operations should start as early as possible d e p e n d i n g u p o n t h e s e as o n . T h e i n i t i al s aw c u t t i n g an d s u b s e q u e n t w i d e n i n g o f g r o o v e s h a l l b e d o n e w i th t h e h el p o f s a w c u t t i n g m ac h i n e w i t h d i am o n d s t u d d ed b l ad e .
Types Of Joints a)Contraction Joints (Transverse) b) Construction Joints (Transverse) c) Expansion Joints (Transverse) d) Longitudinal joints
MORD 1501.8.3 Co n tractio n jo in ts: The contraction joints shall consist of a m ec h a n i c al ly s a w n j o i n t g r o o v e 3m m t o 5m m w i d e an d ¼ t o 1 /3 o f d e p t h o f s l a b as s h o w n i n t h e d r a w i n g s . T h e s aw n j o i n t s s h al l b e c u t a s soon as the concrete has undergone initial h a r d en i n g an d i s s t r o n g en o u g h t o b ear t h e weight of crew and cutting machine. These jo in ts s h all b e s u b s eq u en t ly w id en ed t o 1 0m m w i d t h a n d 20m m d e p t h b y ap p r o p r i at e s a w t o h o u s e t h e s e al a n t . T h e s e j o i n t s s h a l l b e s p a c e d 2.5m to 3.75m as per sketch in Fig.1500.1 H o w ev e r t h e le n g t h o f p a n el (i n d i r ec t i o n o f t r af fi c ) s h a ll n o t b e le s s t h a n t h e w i d t h o f p an e l .
M O RD 1 50 1.8 .4 C o n s t r u c t i o n J o i n t s : Construction joints shall be placed c o n c r e t i n g i s c o m p l e t e d a f t e r a day’s w o r k
when or is
s u s p e n d e d f o r m o r e t h an 3 0 m i n u t e s . C o n s t r u c t i o n
jo in t s h all b e p r o v i d ed at th e lo c at io n o f c o n t r a c t i o n j o i n t . T h e jo i n t s h a l l b e a b u t t j o i n t . Steel bulkhead shall be used to retain the concrete while surface is finished. The joint s h a l l b e w i d e n ed t o 10 m m w i d t h an d 2 0m m depth to house the sealing compound. No em e r g en c y j o i n t s h a ll b e al l o w ed i n l es s t h a n 2m d i s t an c e o f a n y p r e c ed i n g o r s u c c eed i n g jo in t p o s itio n .
Construction Joint details
MORD 1501.8.5 Exp ans io n Jo int s T h es e s h a l l b e p r o v i d e d o n l y n ea r th e b r i d g e s o r c u l v e r t s . Th e ex p a n s i o n j o i n t s h al l consist of a bitumen impregnated joint/pre- moulded synthetic joint filler board about 20m m t h i c k c o m p l y i n g w i th IS :1838 an d d o w e l b a r s c o m p l y i n g w i t h c l 1 50 1.9 o r a s s p ec i f i ed i n t h e d r a w i n g s . T h e d o w el b a r s s h a ll b e p a s s i n g through the holes in the board. Filler board s h a ll b e p o s i t i o n e d v e r ti c a ll y a l o n g t h e l in e o f the joint within the tolerances as per cl.1501.2.7. Adjacent slabs shall be fully s e p a r a t ed b y t h e f i l l er b o a r d
M O RD 1 50 1.9 Do w e l b a r s f o r e x p a n s i o n j o i n t s D o w el b a r s s h al l b e m i l d s t ee l b a r s o f 2 5m m d i a ., 5 00 m m l o n g a n d s p a c e d at 25 0m m c e n t e r t o c e n t er. T h ey s h a l l b e p r o v i d e d a t m i d d e p t h w i t h i n a t o l e r a n c e o f ± 2 0 m m . T h e y s h a l l b e c o v er ed b y t h i n p l as t i c s h e at h i n g n o t t h i c k er t h a n 0 .5 m m f o r h a lf l en g t h + 50 m m . A c l o s e l y f i tt i n g c a p o f 1 00 m m l o n g o f w a t er proofed cardboard or synthetic material like P VC s h a ll b e p l a c ed o v er t h e s h e at h e d e n d o f e ac h d o w e l b a r. A n e x p a n s i o n g a p f i l l ed w i t h compressible sponge/thermocol is to be provided.
E x p an s i o n J o i n t at p o i n t s o f ab u t ti n g s t r u c t u r e s D o w e ls : 2 5m m d i a ., 50 0m m l o n g a n d s p a c e d a t 250mmc/c
Filler board: compressible Joint filler 20mm ± 1.5mm Filler depth 25mm ± 3mm lower than slab thickness Dowel bars (MS rounds) to be covered with plastic sheathing for ½ length +50mm
Shuttering sheets for MS dowels just removed. Observe the bulkhead used to retain concrete
Mild steel dowel rods with sheathing and caps. Groove cutting in progress at expansion joints. Filler board shall be in one piece only.
MORD1501.11.4.3.4 Paving near culverts and bridges P i p e c u l v e r t s : S l ab s h a l l b e c a r r ie d o v e r p i p e c u l v e r t s N ew c u l v e r t / b r i d g e : St r u c t u r a l s l ab o f c u l v e r t / b r i d g e s h al l b e ex t e n d ed o v e r f u l l w i d t h o f a b u t m en t c ap . D u r i n g c a s t i n g d o w e l b a r s s h a ll b e f i x e d at t h e e n d n e ar ex p a n s i o n j o i n t w i t h t h e C C r o a d . E x p o s e d d o w el s a r e c o v e r ed w i t h s h e at h i n g a n d c a p e t c . 1 2m m t h i c k f i l le r b o a r d i n c a s e o f c u l v e r t a n d 2 0m m t h i c k f i l ler b o ar d i n c a s e o f b r i d g e s h al l b e in s e r t ed b e fo r e l ay i n g t h e p a v e m e n t s l ab . F il l er b o a r d , w i t h h o l e s f o r d o w e ls , s h al l b e f o r f u l l p a v em en t w i d t h a n d s h a l l b e i n o n e length. E x i s t in g b r i d g e : E x p an s i o n j o i n t s h a l l b e p r o v i d ed a t e it h e r en d b e t w e en t h e p av i n g s l a b a n d t h e c u l v e r t / b r i d g e s l ab
CC road joint with new b ridge
C C r o a d j o i n t w i t h e x i s t i n g c u l v e r t/ b r i d g e
Details of expansion joint and sealing
MORD1501.8.6 L on g itu d inal Jo in ts: They shall be provided for two-lane road or w h e r ev e r s h o w n i n t h e d r a w i n g s . F o r a s i n g l e l an e road longitudinal joint is not needed. The c o n c r et in g i n t h e en t i r e w i d t h s h a l l b e d o n e i n o n e g o a n d t h e l o n g i t u d i n a l jo i n t s h a l l b e s a w c u t . It s h a ll b e 3 -5 m m w i d e an d o f d e p t h e q u al t o 1 /3r d th e d e p t h o f s l ab ± 5 m m . T h e j o i n t s h a l l b e w i d e n e d t o a g r o o v e o f 6 t o 8m m w i d t h an d 1 2m m t o 15m m d e p t h an d s e al ed w i t h h o t p o u r e d s e al an t a s p e r c l au s e 1501.22. B efor e sealant is p o u red , a baker th read o f n o n -c o m b u s t i b l e m a te r ial l i k e ju t e t h r e ad o r n a r i al r o p e s h al l b e p r e s s ed i n t o t h e w i d e n ed g r o o v e s o as t o l e av e u n f i l l ed d ep t h o f 8 m m t o 1 0m m .
Details of longitudinal joint and sealing
Groove cutting machine
Contraction joint 3 to 5 mm wide 1/3 to 1/4 in depth
Mohammadalipalem road in Guntur District. Joint cutting
Mohammadalipalem road in Guntur District. Joint cutting
Mohammadalipalem road in Guntur District.
Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District. Key wall shuttering
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Mohammadalipalem road in Guntur District. Plate vibratory compaction.
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Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District
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Mohammadalipalem road in Guntur District
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Hanumantnagar road in Bapatla mandal in Guntur District. CC road under finishing
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Hanumantnagar road in Bapatla mandal in Guntur District.
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Hanumantnagar road in Bapatla mandal in Guntur District. CC road thickness being verified.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 22-11-2011. Verifying outside measurements.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 22-11-2011. Concrete strength testing by rebound hammer which gives an approximate indication
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 22-11-2011. Cube testing in the laboratory.
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Causes of cracking in concrete roads 1) Plastic shrinkage of concrete surface due to rapid loss of moisture 2) Drying shrinkage 3) High wind velocity associated with low humidity 4) High ambient temperature 5) Delayed sawing of joints
Shrinkage cracking probably due to late sawing (left) Joint raveling due to early sawing (right) T i m i n g t h e S aw i n g W i n d o w : Joints are usually
constructed by saw-cutting the concrete a few hours after placing. The optimum period of time to saw contraction joints is known as the sawing window. The sawing window for conventional saws generally begins when concrete is strong enough not to ravel excessively along the saw cut. The window ends when significant shrinkage occurs that induces uncontrolled cracking
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Crack caused by late joint sawing
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PQC concreting commenced over 125 micron thick plastic sheet as separation membrane
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Preparation for slump test, casting cubes (150 mm) and beams(70 х 15 х 15 cm)
Concrete Cores in CC roads: Crushing strength of cylindrical specimens =0.8×crushing strength of cubes when the height to diameter ratio of core is 2. Crushing strength of cylinders with height to diameter ratio between 1 and 2 may be multiplied by a correction factor f = 0.11n+0.78 where n is height to diameter ratio. Number of cores = minimum 3 The concrete in the core test shall be considered acceptable if the average equivalent cube strength of the cores is at least 85% of the cube strength of the grade of concrete specified for the corresponding age and no individual core has a strength less than 75% 99
Acceptance Criteria for Cracked Concrete Slabs Slabs with full depth cracks are totally unacceptable as it amounts to structural failures. Other cracks which are deep and are likely to progress in depth with time are also to be considered as serious in nature. Fine crazy cracks are not serious. Slabs with cracks having depth more than half slab depth shall not be accepted. Following type of cracked slabs are acceptable: 1) Length of single crack shall not be more than 750mm, eventhough its depth is less than half of slab depth. 2) Cumulative length of cracks with depth of crack less than half depth of slab in a panel not more than 100
TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 11-02-2012. Core cutting to verify inner depth and compressive strength.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 11-02-2012. Core cutting to verify inner depth and compressive strength.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 11-02-2012. Core cutting to verify inner depth and compressive strength.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 14-02-2012. Core testing for assessing compressive strength of M30 concrete.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 14-02-2012. Core testing for assessing compressive strength of M30 concrete.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 14-02-2012. Core testing for assessing compressive strength of M30 concrete.
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TPQA inspection of R&B road to Mohammadalipalem road in Guntur District 0n 14-02-2012. Core testing for assessing compressive strength of M30 concrete.
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MORD Table 1800.8, Frequen cy of Quality Con tro l Tests fo r P av i n g Q u a li t y C e m e n t C o n c r e t e Pa v em e n t L e v el s a n d A l i g n m en t
Level Tolerance
To be checked for each day’s work (clause 1802.3)
Surface Regularity Longitudinal & Transverse
Regularly
Width of Pavement and position of paving edges
To be checked for each day’s work (clause 1802.3)
Pavement Thickness
Regularly at grid points
Alignment of joints
To be checked for each day’s work
Depth of Dowel bars
To be checked for each day’s work 108
MORD Table 1800.8, Frequen cy of Quality Con tro l Tests fo r P av i n g Q u a li t y C e m e n t C o n c r e t e P av e m e n t Cement an d Water Item
Test method
frequency
One for each source of supply and occasionally when called Cement: IS: 269, IS: for in case of long/ improper Physical and 455, 1489, storage. Besides, the contractor Chemical tests IS:8112 shall also submit daily test data IS: 12269 on cement released by the manufacturer. Water Chemical Tests
IS: 456
Once for Approval of source of supply, subsequently in case of doubt 109
MORD Table 1800.-8, Frequenc y of Quality Con tro l Tests fo r P av i n g Q u a li t y C e m e n t C o n c r e t e P av e m e n t C o a r s e a n d F in e A g g r e g a t es Test
Test Method
Frequency
AIV
IS: 2386-part 4
1 test per source
FIV
IS: 2386-part 1
1 test per source
Deleterious constituents
IS: 2386 part 2
1 test fo each day’s work
Water Absorption/ Content
IS: 2386-part 3
Regularly as required subject to a minimum of 1 test a day for coarse aggregate and 2 tests a day for fine aggregates.
Soundness
IS: 2386-part 5
1 test per source
Gradation
IS: 2386-part 1
1 test per each day’s work
Alkali Aggregate Reaction
IS: 2386-part 7
1 test per source 110
