| With the development of Chinese economy,mass concrete,has been applied more and more in high-rise buildings,bridge and bam.For mass concrete,related special construction technique makes it difficult for construction side.Mass concrete construction presents a high requirement,and then,thermal stresses will be cracking by producing heat of hydration.Moreover,mass concrete subjects an important part in engineers,which subjected complex mechanical properties.Therefore,if mass concrete was cracking,it will affect the massive structure and its stability.Mass concrete related to special construction technique and thermal monitoring are always important research project for colleges and research institution.Mass concrete construction exists special technological difficulty,which is different between mass concrete construction and common concrete construction.Meanwhile,concrete presents low coefficient of heat conductivity,which inner heat of hydration cannot be prone to emit.For this reason,mass concrete will produce thermal cracking caused by thermal stresses which produced by different internal and external temperature,and internal constraining force.When tensile strength of mass concrete cannot subject this thermal stresses,it will be cracking,which affects the stability of project.This dissertation will carry out related research works about mass concrete construction and monitoring technique,based on mass concrete bridge cushion caps of Yong Dinghe bridge project.Combined with specific cushion caps engineering technological difficulty and process,researching for reinforced welded,template installation,pouring of concrete and lay cooling system.Computing the shrinkage deformation,equivalent temperature,elasticity modulus,shrinkage stress,and concrete temperature before and after cooling.Based on specific project,laying and design thermal monitoring system,related attentions,warning mechanism and scheme.Finally,combined with finite element analysis and monitoring data,it can find out the inadequacy of above cooling system,which provides reference to mass concrete bridge cushion caps projects. |
