Research On Influencing Factor Of Permafrost Thaw Settlement Characteristic

Recently, with the development of economy and construction in our country, more and more important projects are built on permafrost, where frozen ground engineering problem may occur because of the special characters of frozen ground. There into, the thaw collapse characteristic of frozen ground is primary problem of engineering freezing damage. but considering the variegation of permafrost genesis in every quarter, physical makeup differ in thousands ways, the comparatively intricacy structure of the frozen soil. Thus, in order to solve permafrost causing thaw collapse freezing damage problem, it is necessary to appraise and make research on the thaw collapse characteristic of permafrost.In view of previous status, this article incorporation the item of Daqing petroleum design institute, "The survey and design of petroleum pipe line that connects China and Russia", with the frozen soil along the petroleum tube line for subject investigated, proceeding substantive thaw collapse test and every other index of correlation experiment in frozen ground testing laboratory. In this foundation make research on permafrost thaw collapse characteristic by induction, regression and more analytical procedure, and obtaining the correlation conclusion, full text in all divide five part.this article introduces gist of selected subjects in the first part, and the research status of frozen ground thaw collapse characteristic at home and abroad, as also textual some element task and investigative clue technical line.this article describes test set, experimentation step and test conditions in second part, and compendious introducing the mechanism of frozen ground thaw collapse characteristic.In third part, this article analyses and makes research on test result. Firstly, describing severalty factor that impacts thaw collapse characteristic. According to practical situation and test conditions, this article mostly select three factors of water content, dry density and earthiness to study and analyses; Secondly, according to test data this article individual proceeds linear and non-linear regression analysis about three factors to thaw collapse characteristic effect, obtaining rational calculation procedure through comparison. Through analyses, we found out following conclusion: coefficient of thaw collapse increases in company with augmentation of water content, coefficient of thaw collapse and water content submit better linear positive correlation relation; thaw collapse coefficient of frozen ground rapid decreases in company with augmentation of dry density, while dry density increase to a certainty degree, reduced degree of thaw collapse coefficient of permafrost gradually let down along with the increment of dry density, coefficient of thaw collapse and dry density submit better nonlinear correlation relation; thaw collapse coefficient diminishes with granulometric coarsening, while earthiness high in clay soil grain is strong in thaw collapse characteristic; Lastly, incorporating practical situation, considering combined influence of multi factor to thaw collapse characteristic of soil mass in certain frozen condition, comprehensive anglicizing different earthiness thaw collapse test data, and got out correlative calculation procedure. then calculated value and observed value proceed contrastive analysis, result is comparatively satisfactory.In fourth part, in order to preferably demonstrate rationality of text computational solution, this article introduce some kind of internal calculation procedure and normative calculation procedure. Then, comparing and analysesing the result that textual method of calculation and every other method calculat, through the comparison of figure, we find out the result that every other method calculats is larger than that of this article.In fifth part, it was textual conclusion. Through the analytical study of above four parts to thaw collapse characteristic influencing factor, we have regularity known to thaw collapse characteristic phenomena, and accumulating experience for henceforth further on studies.