Study On Mechanism Of Foundation Bulging Disease In A Building In Qinghai

This paper takes the gray soil foundation of a building in Qinghai as the main object of research.Firstly,the disease status of the building and the environment of the building were investigated.The physical and chemical properties of the gray soil foundation at the bottom of the building were analyzed.Secondly,the main warehouse,1# sub-depot and 2# sub-library were respectively.The deformation observation and deformation analysis of the wall column and the floor were carried out.Thirdly,the soil sample collection and laboratory test of the ash foundation were carried out,and the composition and expansion characteristics of the soil sample were analyzed.Finally,the swell mechanism of the lime soil was discussed.And the characteristics were studied.Through the on-site soil sampling and indoor experiments,the influencing factors of the basal bulging of the ash foundation were obtained,and the treatment measures for the bulging of the ash foundation were proposed.The cracks and bulging deformation of the building were carried out.The deformation monitoring of the system provides a monitoring basis for taking measures to reduce the bulging deformation.The effectiveness of reducing the deformation deformation is verified by deformation monitoring.The study found:1.The main building of the building,the 1# deputy warehouse and the 2# sub-depots have a large bulging pattern.The surrounding area is large and small in the middle,showing a “bottom-like shape”;the minimum bulging of the main building of the building occurs.In the middle is 2mm;the maximum bulging amount appears on the north side is 111 mm,the north side bulge is more serious than the south side;1# sub-depot and 2# sub-depot indoor floor also appear uneven bulging phenomenon,surrounding the wall part The deformation is large and the middle is relatively small.2.Studies have shown that the limestone Ca O is not fully matured in the ash foundation.When the water is absorbed,the Ca(OH)2 agglomerate of the mature lime is doubled,which is the main reason for the bulging of the ash foundation of the building.The swelling phenomenon caused by the swelling of the sulfate formed by the sulfate in the foundation soil to cause the swelling of the foundation is a secondary factor causing the swelling of the foundation.The rain water expands into the foundation through the outdoor scattered water to accelerate the foundation bulging,which is the cause of the foundation bulging.3.In the case of mechanical control measures,reduction of internal factor replacement measures and waterproof measures,it has a good effect on preventing bulging deformation.Among them,the mechanical control measures include setting anchor bolts,prestressed anchor cables to suppress expansion,and stacking back pressure;replacement measures include excavating part of the Sanqi lime soil,reducing expansion potential,and changing cement soil;waterproof measures include setting drainage ditch,Go to the green belt to reduce the infiltration of rain.