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ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
PAVEMENT ANALYSIS AND DESIGN (ELECTIVE-II)B.E. EIGHT SEMESTER
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 1
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
UNIT – 4 7) RIGID IRC58, PCA, AASHTO method of design, design of joints and reinforcements. Flexible:
US Corps of engineering, CBR, FAA, McLeod (Canadian) Rigid PCA, FAA & LCN, Ultimate load
analysis yield lines patterns method.
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 2
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 3
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 4
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 5
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 6
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 7
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 8
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 9
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 10
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 11
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
PCA (PORTLAND CEMENT ASSOCIATION) METHODThe Portland Cement Association (PCA) uses Westergaard theory with finite element
analysis (FEM). Design charts were developed based on allowable number of load repetitions related to properties of pavement materials at failures. These were correlated with theoretically calculated maximum edge stress and corner deflection of slabs. The supporting layer and the cement concrete slab are characterized by the (effective) modulus of sub – grade reaction and the characteristic 28 day compressive strength of the cement concrete respectively. The failures of pavement considered are
(i) Fatigue cracking of slab due to cumulative damage caused by different axle load groups and
(ii) Erosion or pumping of supporting layer of the concrete slab.
I) Fatigue cracking of slab due to cumulative damage caused by different axle load groups:-In the fatigue analysis, the stress ratio between the maximum stress at the edge when loaded at
the outer edge and the flexural strength of concrete is calculated. The computed stress ratio is related to the maximum allowable number of standard axle load repetitions. A fraction value is calculated by dividing the actual repetitions with allowable repetitions of each type of axle group. As a safe design, such fraction values obtained from different axle load groups are cumulated. The value should not be more than one.II) Erosion or pumping of supporting layer of the concrete slab:-
For erosion criterion of the supporting layer (sub-base or base), maximum deflection of the slab corner is considered as critical. The design charts were validated with the performance data of various in-service pavements and road tests. Slab thickness should be derived through the above two failure criteria. Warping stresses due to variations in temperature and moisture are not considered in this method. The rate of increase of slab thickness for decreasing values of the sub-grade’s modulus was found to be consistent.
As the first step of design, a trial slab thickness is assumed and verified with the design criteria. From the next trial onwards, the slab thickness is suitably increased or decreased until the above two design are satisfied. The final design thickness is taken as the thickest value which is obtained using the above two considerations.
The PCA design method has been adopted by Austroads (1992) for the design of slab thickness in which the slab is supported on cement treated layer.
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 12
ANJUMAN COLLEGE OF ENGINEERING & TECHNOLOGY MANGALWARI BAZAAR ROAD, SADAR, NAGPUR - 440001.
DEPARTMENT OF CIVIL ENGINEERING
Prof. Rashmi G. Bade, Department of Civil Engineering, Pavement Analysis & Design 13