Researching Of 500Kv Power Line Filling Pile Foundation Up-pulling Mechanisms And Its Treatment

There are much freezing damage in our country. it is verysignificant and real important to Appraise, predict , and dealwith freezing damage. There are many specialists to researchswelling phenomenal , and havey fruit. Reading relative booksriches my knowledge , while helping finish my papers.Compresol piles are widely applied in bridges of highwayand railway , and large industry , civil buildings. This specialfoundation type are successful generally in power equipment.The papers talks about compresol piles , severity and typical ,up-pulling phenomenon of yi-min he electric power plant,analysis the up-pulling mechanics , and put forward propersalvation, and finally test the treating effect.North power equipment is generally attached freezingdamage, there are , equipment building damage ,cable gapcracking , retaining wall splitting , equipment foundationdisplacing for freezing, due to equipment health stationdescending, and finally even loss the using condition.. thepapers talks about compresol piles of power foundation, infrozen zoom , up-pulling mechanics, which help for judgingpower foundation ,special for pile foundation, abnormal station.the papers present the engineering position , and stratumcharacter of yi-feng fiist line #645, in which the foundation werediscarded for several up-pulling, and yi-feng second line #122,which foundation piles up-pulling displacement was little andafter being treaded relieved the defect. First , checking pilesbody integrity, to eliminate the possible reason in construction,and component analyzing to exclude the salt heave reason.Grading analysis , soil sample physical property analysis , andwatching the relationship between site pile body up-pullingdisplacement and temperature, confirm, the reason isswelling heave. Testing soil sample from yi-feng first line #645,which foundation up-pulling was several, and sample fromyi-feng second line #122, which foundation up-pulling wasrelatively light, under no water supplement condition , withdifferent moisture content, different cooling rate, using zerodisplacement and static pressure balance experiment methods,we measured the maximal frost-heave force. swellingexperiment verified the contribute of soil component ,temperature to freezing heave. The frozen-heave factor errorbetween experiment result and the watching data state , frozenheave happening or not is lied in the different between thewater translocation freedom and ice-suction effect in theconsolidation process .In the way of conclusion , due to powerengineering project plan , design , construction , execution ,operation ,the papers put forward detail salvation to preventfoundation frozen-heave.According to the experiment , treading , watching result ,the conclusions we get are :1.water , soil condition , temperature are the major factorsto cause swelling. Under given soil and temperature condition ,water , intrinsic factor , is the chief element to causefrozen-heave. The difference of inner frozen experimentresult data without water supplement and the spit watch datastates, it is water , lying with various station in frozen soil ,translates freely and quickly , which determines the frozendifference. Compresol pile frozen heave or no is also related tothe spit soil frozen-heave factor. When the spit soil is strongswelling or supper strong swelling, piles are easily heaved,evenly when the pile bed depth is deeper than frozen depth , itis probable to cause up-pulling, because of frozen-heave forcein the iterated freezing-thawing course in the seasonally frozenground.2.when the pile body surface is not smooth enough or hassags and crests, frozen heave effect is aggravated withtangential frozen load.3.due to the randomness of frozen soil freezing-thawingcourse, which causes the difference of the up-pullingdisplacement of the iron tower`s four piles, the tower probabletitles at any direction.4.for the inertial character of seasonally frozen soil, in thematching condition place , such as swamp land, if not changingthe general frozen state, the frozen up-heaving would raisewith years, that is , the D-value between up-heaving and thawcollapse is rising. In this way , compresol pile foundation iscommon with cement post foundation, and precast or cast slabfoundation basically.5.changing swelling clay around pile with loose gravle ,cobble or other material, only if not effecting the foundationstrength, could effectively abate the tangential frozen force, inconsequent, control the up-heaving. The changing fill depthshould deeper than the must frozen depth. After treated , thetendency of frozen up-heaving and thawing collapse is uniform,up-pulling is controlled.