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RESULTS Between the Bureau and Vibronics, about 34 data channels were used for each blast. A comprehensive future report will list all measurements; however, only triglrliglrts are Irresented in this paper. Table 3 lists the hiyhest measured ground vibrations, pipeline vibration responses and strains for each blast. Figure 4 shows a set of vibration acrd strain records from blast flo. 25. (tote that strains resemble vibration records, cycling nearly symmetrically about the zero line. Therefore, tension and compression amplitudes were about equal. Vibrations Vibration amplitudes on the buried pipelines were less than correspondiny R and V components measured on the ground directly above (shallow burial). This consistent and significant reduction of about 40 pct at a depth of only 3-4 ft was surprising, however, it is entirely in agreement with other studies including Bureau of tdines iti 6969 (Ref. 6), wiriclr examined the effects of vibration monitoriny on basement walls and floors. Figure 5 summarizes the surface radial vibra[ion component and corresponding horizontal response of the 20-in pipeline. Vertical vibrations behaved similarly. Vibration frequencies of some blasts were low for the relatively small distances. As shown in figure 4, the radial component of shot llo. 25 is about 5.6 liz. This is possibly a site phenomenon caused by the thick clay layer over the shale. Strains Figures 6 tlrrouglr 10 show a variety of comparisons of measured strains and surface ground vibrations. These are obviously not fire only correlations possible out of 34 total independent channels and, in some opinions, not the best choices. The Sarltl authors calculated stresses from blasting parameters (explosive type, amount, distance, etc.) and believe that particle velocities will not consistently be related to strains (and stresses). The Fig. 6-10 plots suggests that rouylr correlations aritlr velocities or at least maximum envelopes covering all the Iriglrest measurements are possible. Alternatives could be direct pipeline vibration response, conversions of velocities to displacements, computations of stress and strain propagation equations, etc. The autlror-s anticipate future examinations of alternatives. Strains are relatively high for the PVC pipeline by contrast with the steel, consistent with its lower stiffness. If the pipelines were all fully coupled and moving witty the ground, this difference should not exist. Tlris problem will be examined in more detail in the follow-up comprehensive report. Generally, similar measurements on the steel pipelines gave similar amplitudes (e.g, front longitudinal strain of a 12-in agreeing roughly with other front longitudinal measurements). Circumferential strains were often, altlrouylr not always, the hiyhest, particularly when measured on top compared to on the side. • 133