Design Methods For Loading Capacities Of Connection And Flexural Member In Structural Glass Considering Environmental Effects

Recently,the connection and laminated glass member with ionic polymer(SG)as interlayer were in favor of architects and widely used in the field of building structural elements due to their unique appearance and well mechanical properties.However,the sensitivity of environmental effects(including temperature and aging effects)on the mechanical behaviors of SG material also results in the relevance between loading capacities of corresponding connection and member in structural glass and environmental effect.However,there is lack of relevant design provisions of loading capacities of connection and member in structural glass in current design specification.This thesis takes structural glass embedded laminated connection(ELC)and flexural member as the main objectives whose loading capacity are seriously affected by environmental effects.A series of experimental,numerical and analytical studies were conducted in the levels of SG material,the interface of metal and SG,connection and member,respectively.And the design methods were proposed for the loading capacities of structural glass ELC and flexural member considering environmental effects.The main works and conclusions of this thesis are summarized as below:(1)In the level of SG material,uniaxial tensile,DMA,environmental aging tests and microscopic analysis were applied to explore the mechanism and law of environmental effects on mechanical properties of SG material.The uniaxial tensile strain-stress constitutive model,dynamic viscoelastic constitutive model and aged initial modulus prediction model of SG considering environmental effects were developed,which were contributed to supply theorical and data supports for subsequent studies on loading capacities of ELC and flexural member.(2)In the level of interface of metal and SG,double shear,environmental aging tests,microscopic characterization and numerical analysis were conducted to explore environmental effects on the bonding capacity between metal and SG,and interface stress distribution uniformity.The bonding capacity prediction model considering environmental effects was then proposed and coefficients of temperature and environmental aging were also given,which was used to supply data support for design method of ELC.(3)In the level of connection,mechanical tests and numerical analysis were conducted to reveal the failure modes(brittle failure mode,progressive failure mode and delamination mode)and failure mechanisms(glass cracking and delamination between metal and SG)of ELC.The effects of key mechanical parameters on failure mode and loading capacity were also investigated.And the judgement of failure mode and design method of loading capacity for ELC were proposed,based on load transferred path,bearing mechanism and bonding capacity prediction model between metal and SG considering environmental effects.(4)In the level of flexural member,amendment stress effective thickness model and glass lifetime strength model were established based on the flexural characteristics of laminated glass and the propagation and failure laws of micro crack in glass surface,respectively.Environmental aging,flexural tests were combined with SG’s constitutive laws obtained in Chapter 2 to explore the environmental effects on the modulus of SG interlayer in laminated glass.Based on those,the design method of loading capacity of structural glass flexural member considering the environmental effects and load history was established.