Since that earlier work there have been improvements in polyurethane chemistry and the causes of the failures of previous tests have been identified. Goals were that the foam expanded significantly and harden to a chillable firmness quickly. In past work polyurethane foam was tried with limited success in laboratory tests and GDO sponsored field tests.
Sandia National Laboratories is developing polyurethane foam as a chemical grout for lost circulation zones. Hence, successful grouting relies heavily on good engineering judgement and experience, and not on a basic set of standard correlations or equations. In many cases, the method that proves successful reflects a small abnormality in the ground or structure rather than its overall characteristics. Once a desired effect is obtained, it is difficult to credit any one procedure with the success because the results are due to the summation of all the methods used. In most cases, it is a trial and error procedure where an inexpensive method is initially tried and then a more expensive one is used until the desired results are obtained. Grouting is very much an art and not a science. The breadth and depth of the study was assured by conducting the main part of the review, the collection and evaluation of information, without specifically considering the borehole sealing problem (but naturally incorporating any aspect of civil engineering applications that could be of potential use).
Ye tera dil samajhta hai ya mera dil samajhta hai.A comprehensive description of grouting applications in civil engineering is presented that can serve as a basis for the selection of grouting methods in the borehole sealing problem.
Main tujhse door kaisa hoon, tu mujhse door kaisi hai Magar dharti ki bechaini ko bas badal samajhta hai (x2) “Koi deewana kehta hai, koi pagal samajhta hai, Listen to this beautiful rendition of Koi Deewana Kehta Hai in the voice of Ashutosh Rishi.
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