Time reversal techniques are used in ocean acoustics, medical imaging and non-destructive evaluation to backpropagate recorded signals to the source of origin. We demonstrate experimentally a technique which improves the temporal focus achieved at the source location. The experiment consists of propagating a signal from a transducer within a concrete block to a single receiver on the surface, a...

Unbalanced forces developed by hammer wear and impact must be resisted by auto shredder foundations. Methods for estimating the impact forces are described. Because of different soil conditions, a concrete mat, a concrete block, and a pile.supported foundation system were adopted at three different construction sites. The design procedures involved in determining the dynamic response for each t...

The objective of this effort was to investigate the similitude between assemblages and components constructed from full-scale and 1/3-scale concrete block, mortar, grout, and reinforcing steel. This study serves as a preliminary investigation to the testing of a complete 1/3-scale partially grouted, lightly reinforced concrete masonry building for seismic resistance. This effort is motivated by...

class Node class *Node extends Node 2.2.2 Blocks Nodes are grouped into basic blocks using a hierarchy of Block classes. The hierarchy is composed of five interfaces, two abstract classes, and four concrete classes. package org.checkerframework.dataflow.cfg.block;

an experimental program was conducted to determine the effects of geosynthetic reinforcement on mitigating reflection cracking in asphalt overlays. the objectives of this study were to asses the effects of geosynthetics inclusion and its placement location on the accumulation of permanent deformation. to simulate an asphalt pavement overlaid on top of a crack in a concrete or asphalt pavement, ...