Crack and structural response to construction trench blasting was measured in a woodframe house with a stucco exterior. Blasts at distances between 232 m to 368 m produced peak particle velocities (PPV) and air blast over pressures (AB) of 9 mm/sec and 0.02 kPa (123 dB), respectively. Structural response velocities...
This thesis summarizes two further developments of the Autonomous Crack Monitoring (ACM) system, which facilitates simultaneous measurement of crack response to environmental changes and various dynamic events. The first component was measurement of crack responses in three different materials and locations in a residential structure subjected to ground vibrations produced...
This thesis summarized the qualification and testing of two commercial Autonomous Crack Monitoring (ACM) systems for use in measuring micrometer displacement of cracks. Qualification involved the assessment of both laboratory and field performance in a residential structure subjected to nearby quarry blasting for the production of roadway aggregate. Aggregate and...
A unique judicial opportunity allowed measurement of the response of three cracks in residential structure to blasting for underground aggregate mining. Instrumented cracks were located in the interior basement CMU mortar and upstairs dry wall as well as exterior brick work. The dynamic environment was unusual. Even though the blasting...
Micro-meter dynamic crack responses in a two story structure to rock blasting- and wind gust- excitation are compared to those induced by long term climatological effects. These measurements substantiate the conservancy of the 12.5 mm/s (0.5 in./s) blasting vibration control to protect residential structures against cracking. The test structure was...
This paper describes the technology and methods deployed in the continuous autonomous remote monitoring of cracks in interior and exterior walls of a residence near a limestone quarry. The object is to quantitatively compare crack response to blast-induced ground motion to that induced by diurnal temperature changes, weather fronts, and...
In this paper vibratory crack response is compared to that produced by volumetric changes in foundation soils induced by natural events. These natural phenomena include changes in the water table, changes in soil moisture, and formation of ice lenses to name a few. Previous papers have compared vibratory responses of...
Cosmetic and structural cracks are a large concern for homeowners. Although these cracks can develop from a variety of causes: differential foundation settlement, occupant activity, climatological effects, as well as dynamic events, people tend to look to dynamic events like blasting, construction, or traffic vibrations to be the culprit. This...
The notion of blasting, even in a controlled setting such as a limestone quarry, can be alarming to residents and business owners within earshot. Because humans are inherently sensitive to blast-induced vibrations, they perceive that the structures in which they live in are equally sensitive. The goal of this project...
This appendix contains all software used to program the MICA2 motes for Version 1 of the MICA2-based wireless ACM system. This appendix is organized by software directory and only the modified files are included.