Study On The Characteristics Of Temperature Field Of Frozen Soil Wall In Cretaceous Formation

How to meet the water through the mud of the cretaceous stratum has became the engineering technicians focus of concern in the west during the height of the well construction background. Now began to widespread use of the freeze construction methods to solve. But for the cretaceous stratum the frozen wall temperature field research is still in the initial stage. This paper in Inner Mongolia BoJiangHaiZi mining area east wins tabor-freezing wind well in the cretaceous stratum for research object, and the cretaceous stratum of frozen wall temperature field in the shaft freezing-build by laying bricks or stones-nature thawing process to dig.Use of field freezing process measurement temperature holes monitoring the data obtained, and combined with the development of freezing method to cut well safety information visualization network platform software, a group of representative on temperature field rock freezing process were analyzed. Compared the different cooling rate of rock mass, and obtained freezing process different period the average temperature of the frozen wall, effective thickness parameter index, that late freeze frozen wall average temperature stability in-12.8℃-13.5℃, and between the effective thickness stability in the4500mm to5000mm or so, that single circle tube freezing can satisfy the wellbore dug build by laying bricks or stones requirements. Through to the wellbore outer shaft wall and build by laying bricks or stones to dig during the frozen wall of internal temperature field real-time monitoring, won the hydration heat effect by concrete frozen wall melt, and back to the frozen process temperature field change character and the cretaceous stratum melt frozen wall deep range. Frozen wall and that between outer shaft wall laid a thin plastic film, concrete is temperature curing time can be up to10d above, to ensure the concrete is temperature curing time, to simplify construction craft effect. In the freezing station stop and cooling, frozen wall of natural thaw, continue to keep the WenKong test layer of a temperature data acquisition, and combining with the frozen wall temperature change measuring internal radial, comparison with different lithology thaw rate, melting in the cretaceous formation stage that the temperature changes with time curve can be used to power function fitting said wellbore along the radial direction different temperature and distance measuring position well help distance relation can use a quadratic function to fitting said; Obtained different lithologic stratigraphic frozen wall melt rate, and the corresponding melts frozen time than, the grain needed conglomerate, sandstone melt frozen than time ranged between0.8and1.0, and sandy shale melt frozen needed time than are ranged between1.25and1.5. The234m mudstone as an example, by using finite element analysis software FLAC3D freeze and melting process temperature field numerical simulation, get the results and the field measured results.This paper by field measurement, numerical simulation method of combining the, won the cretaceous stratum of frozen wall temperature field formation and melt rule, to dig build by laying bricks or stones and wall wellbore safety after grouting selection of best time have certain reference significance.Figure74Table19Reference68...