This report contains the results of laboratory analyses of various piling specimens removed from pile trestles after in-place treatment with an organic solvent solution of pentachlorophenol, hereafter referred to as penta preservative. The results of these analyses can be summarized as follows: 1. Piling removed from a trestle immediately after it has received in-place internal preservative treatment with a penta solution and analysed three months later showed that the depth of penetration outwardly from the void was about 1/2 in. After one year the indicated depth of penetration in this same pile was about 1 in. 2. Piling removed from a trestle eleven years after in-place penta treatment indicated that the penetration outwardly from the void was 3 to 4 in. 3. Piling removed from a trestle three months after in-place treatment and analysed three months later indicated that the penta solution had penetrated about 2-1/2 in. into the shell of sound wood. 4. The Gainesville, Florida, test plot data indicates that life of 15 to 20 years can be expected from specimens having a retention of only 0.23 lb per cu. ft. The last inspection was made after an exposure of 124 months, but the downward slope of the three retention curves would indicate that a total life of 15 to 20 years might be expected from the treated specimens. As shown, the untreated specimens lasted only about 3 years. No specimens were treated to retentions less than 0.23 lb. per cu. ft., however, it seems reasonable that a curve showing the decay rate of specimens with lower retention would fall somewhere between the 0.23 lb. per cu. ft. retention curve and the no treatment curve. Some of the retention values found in the piling specimens and reported herein are less than 0.23 lb. per cu. ft. and the decay of such piles can be expected to continue at a faster rate than those with the higher retentions. The specimens in the Gainesville test plot are under a severe exposure of decay and represent conditions below ground. For specimens above ground the indicated rate of decay would be less than that shown on Figure 13 with a greater expected specimen life. G. Discussion and Conclusions. The results of this analysis comprise two groups of investigations: First: Both quantity of retention of penta and depth of penetration into the timber immediately or shortly after it had received in-place treatment; Secondly: After a considerable time interval that affected both the depth of penetration and the distribution of penta retention in the wood.

Media Info

  • Features: Figures; Photos; Tables;
  • Pagination: 19 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00097263
  • Record Type: Publication
  • Source Agency: Association of American Railroads
  • Report/Paper Numbers: ER-86
  • Files: TRIS
  • Created Date: Jul 29 1975 12:00AM