Critical load position for cavities beneath CRCP slab under vehicle loading

In order to study the critical load position that causes cavities beneath the continuously reinforced concrete pavement（ CRCP） slab under vehicle loading, the elliptical load is translated into the square load based on the equivalence principle.The CRCP slab is analyzed to determine the cavity position beneath the slab under vehicle loading. The influences of cavity size on the CRCP slab＇s stress and vertical displacement are investigated. The study results showthat the formation of the cavity is unavoidable under traffic loading, and the cavity is located at the edge of the longitudinal crack and the slab corner.The cavity size exerts an obvious influence on the largest horizontal tensile stress and vertical displacement. The slab corner is the critical load position of the CRCP slab. The results can be used to assist the design of CRCP in avoiding cavities beneath slabs subject to vehicle loading.

Rubblization: A Practical, Cost Effective and Sustainable Option for Repairing Deteriorated Airfield Pavement in the Empty Quarter Desert of Saudi Arabia

Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like the Middle East and this paper presents the design and construction challenges posed while assessing damaged concrete runway in empty quarter of Saudi Arabia. A number of design options for repairs for runway pavement were considered and rubblization was chosen as a preferred option for repair. This paper includes the consideration for the assessment and adoption of the concrete rubblized modulus value using the falling weight deflectometer, optimization of the tests for the whole runway using the Heavy Weight Deflectometer HWD testing to replace pits, safely working around the utilities, reasonable assumption of drop height of the pavement and installation of utility conduits in the rubblized layer. Findings of the paper demonstrates resolving technical issues which are not very well covered in the Federal Aviation Authority (FAA) EB-66 such as the additional test strips, minimum areas of rubblization for assessment using test pits, drop in the height of concrete surface and fixing of utilities in rubblized pavement. The case study demonstrates that the rubblization can be successfully carried out in remote locations like empty quarter of Saudi Arabia with carefully carried out detailed site investigations, adopting correct assumed design rubblization modulus, quality control using HWD, protection of utilities while rubblizing and use of polymer modified asphalt for successful project deployment.