Technology Research On Anti-radiation Shieding Mortor Of Radiation Chamber Wall

The high-energy linear accelerator is introduced in radiotherapy clinic ofQinhuangdao First Hospital to meet the needs of different patients and improve thetherapeutic effects. For the improvement of the energy of the radiation under workingconditions, the existing treatment room can meet the requirements of radiation protectiondifficultly and the walls of original structure which do not meet the requirements need tobe reconstructed. In this paper, the optimization design of shielded transformation for thetreatment rooms is raised combining with this renovation project.Shielding performances and mechanical properties of three materials are comparisontested and analyzed in the shielding transformation design. The materials are respectivelyare shielding mortar with main aggregates of heavy crystal sand, shielding anti-crackmortar mixing heavy crystal sand and superfine steel fiber, shielding anti-crack mortarmixing heavy crystal sand, activity lead powder and superfine steel fiber. Test resultsshow that heavy crystal sand has a higher shielding performance. Superfine steel fiber hasa small impaction on the shielding properties of mortar, but it can significantly improvethe mechanical properties of mortar, the flexural strength can be increased by27%and thespecimen has a strong deformation capacity in the process of stress. Activity lead powdercan improve the shielding performance of mortar but the improvement effect is notobvious, and it seriously affect the mechanical properties of mortar, the flexural strength isreduced by22%when the activity lead powder is incorporated in an amount of30%ofcementitious material.According to weekly work load and management control method of weekly radiationdose, the shielding walls of original treatment room are calculated theoretically, theconcrete and different shielding mortars are used to thicken the wall which does not satisfythe protection requirements, transformation programs are optimized from the perspectiveof construction and economic benefits. Results show that: the shielding anti-crack mortarmixing heavy crystal sand and superfine steel fiber is used in the renovation project oftreatment room with a small increase in wall thickness, good protection of work space intreatment room, the mortar has good shielding performance and mechanical properties, simple construction process, lower construction cost and can meet the engineeringrequirements well.