This study is concerned with the development of design specifications for the use of transverse post-tensioning in concrete bridge decks. The ultimate goal behind this proposal is to improve the durability of concrete bridge superstructures. Experimental results from previous studies are used to validate the analytical models implemented in the development of the design specifications. It is fo...

It is shown that the size effect predicted by dimensional analysis of fracture mechanics of failures due to progressive distributed microcracking agrees with the test data existing in the literature better than the presently used strength (ultimate load) criterion, which exhibits no size effect, and better than the linear i!lastic fracture mechanics criterion, which exhibits much too strong a s...

The objective of this research is to investigate the advantages of using large-diameter 0.7 inch prestressing strands in pretention applications. The advantages of large-diameter strands are mainly beneficial in the heavy construction applications. Bridges and tunnels are subjected to a higher daily traffic with an exponential increase in trucks ultimate weight, which raise the demand for highe...

Imaging techniques are high in demand for modern nondestructive evaluation of large-scale concrete structures. The travel-time tomography (TTT) technique, which is based on the principle of mapping the change of propagation velocity of transient elastic waves in a measured object, has found increasing application for assessing in situ concrete structures. The primary aim of this technique is to...

Trees are able to maintain or modify the orientation of their axes (trunks or branches) by tropic movements. For axes in which elongation is achieved but cambial growth active, the tropic movements are due to the production of a particular wood, called reaction wood which is prestressed within the growing tree. Several models have been developed to simulate the gravitropic response of axes in t...