Page 134 - SAPEM-Chapter-10-2nd-edition-2014

South African Pavement Engineering Manual
Chapter 10: Pavement Design

Figure 56. Concrete Block Pavement Design Curves for Road Pavements

9.5 General Aspects for Design of Block Paving

The success of block paving depends on:
• The use of a stabilized subbase to provide adequate support to the blocks and the sand blanket.
• A sand blanket of 15 to 30 mm in which the blocks embed.
• The width of the joint is between 3 and 5 mm.
• The quality of the jointing sand.
• Confinement on the sides of the paved area to hold the blocks in place.

Desirable Aspects of Mechanistic Cautionary Aspects for Mechanistic
Design for Block Pavements Design for Block Pavements
• Range of methods from simple to more • Rehabilitation design procedures not included
complicated computerised methods
• South African input to design models • Computer based models allow for limited
pavement material types

9.6 Software Packages for Concrete Block Pavement Design
9.6.1 Lockpave
Lockpave is distributed together with Permpave, a design method for permeable concrete paving, by the Concrete
Manufacturers Association (CMA). The program calculates the critical stresses and strains occurring either on or near
the vertical load axis at the bottom of all bound (brittle) layers and at the top of the subgrade. The service life of the
pavement is predicted. Conversely, for a designated service life, it is possible to calculate what values of stress and
strain can be tolerated and, by trial and error, to determine the combination of layer thicknesses required to not
exceed these stresses and strains. Table 56 summarises the functionality of Lockpave.

Section 9: Structural Capacity Estimates: Concrete Block Pavements
Page 123