目前世界各国都采用棱柱体试块(试块尺寸、所配钢筋直径和配筋率各国有差异)的限制膨胀率来表征实体工程的应力—应变关系,但关于棱柱体试块与实际工程中构件之间的相关度尚无系统的研究资料。为此,本试验通过在预先贴好应变片的钢筋网...目前世界各国都采用棱柱体试块(试块尺寸、所配钢筋直径和配筋率各国有差异)的限制膨胀率来表征实体工程的应力—应变关系,但关于棱柱体试块与实际工程中构件之间的相关度尚无系统的研究资料。为此,本试验通过在预先贴好应变片的钢筋网中浇筑掺加HCSA膨胀剂的高性能混凝土,模拟受边梁约束的配筋混凝土板,之后将在线采集到的钢筋应变与按照国标GB50119-2003做出的棱柱体限制膨胀率进行比较。结果表明,棱柱体试块的限制膨胀率可反映补偿收缩混凝土平板构件的变形趋势,受约束程度是影响变形的主要因素,有限元软件SAFE Plus w/Detailer Version 8.1.0分析结果验证了这一点;适当提高混凝土膨胀率有利于改善边界受边梁约束的平板的抗裂性能;应变片的粘贴精度是导致混凝土变形测量误差的关键因素。展开更多
Geopolymer cements provide an alternative to the Portland cement used to produce structural concrete.In this study,geopolymer cements were used to create concrete having compressive strength in the range of 34 to 83 M...Geopolymer cements provide an alternative to the Portland cement used to produce structural concrete.In this study,geopolymer cements were used to create concrete having compressive strength in the range of 34 to 83 MPa(5,000-12,000 psi).The mechanical properties of these concrete materials were evaluated to determine the compressive and tensile strengths and immediate and long term elastic behaviors.The geopolymer cement concrete(GCC)was found to perform in a similar manner to Portland cement concrete(PCC).Long term shrinkage and creep properties of GCC materials were found to be lower than the values typical for PCC.展开更多
在不同温度下对高模低收缩 PET 工业丝进行拉伸性能测试,得到初始模量、断裂伸长率、强度、Lase—5、模量极小值E_(min)及相对应的伸长率ε_(min)等几个力学指标以及不同温度下的应力—应变曲线。通过分析得出:高模低收缩PET工业丝在实...在不同温度下对高模低收缩 PET 工业丝进行拉伸性能测试,得到初始模量、断裂伸长率、强度、Lase—5、模量极小值E_(min)及相对应的伸长率ε_(min)等几个力学指标以及不同温度下的应力—应变曲线。通过分析得出:高模低收缩PET工业丝在实验温度下的拉伸为均匀拉伸,无细颈产生,力学性能随温度的上升呈下降趋势,但未出现急剧下降的现象。展开更多
文摘目前世界各国都采用棱柱体试块(试块尺寸、所配钢筋直径和配筋率各国有差异)的限制膨胀率来表征实体工程的应力—应变关系,但关于棱柱体试块与实际工程中构件之间的相关度尚无系统的研究资料。为此,本试验通过在预先贴好应变片的钢筋网中浇筑掺加HCSA膨胀剂的高性能混凝土,模拟受边梁约束的配筋混凝土板,之后将在线采集到的钢筋应变与按照国标GB50119-2003做出的棱柱体限制膨胀率进行比较。结果表明,棱柱体试块的限制膨胀率可反映补偿收缩混凝土平板构件的变形趋势,受约束程度是影响变形的主要因素,有限元软件SAFE Plus w/Detailer Version 8.1.0分析结果验证了这一点;适当提高混凝土膨胀率有利于改善边界受边梁约束的平板的抗裂性能;应变片的粘贴精度是导致混凝土变形测量误差的关键因素。
文摘Geopolymer cements provide an alternative to the Portland cement used to produce structural concrete.In this study,geopolymer cements were used to create concrete having compressive strength in the range of 34 to 83 MPa(5,000-12,000 psi).The mechanical properties of these concrete materials were evaluated to determine the compressive and tensile strengths and immediate and long term elastic behaviors.The geopolymer cement concrete(GCC)was found to perform in a similar manner to Portland cement concrete(PCC).Long term shrinkage and creep properties of GCC materials were found to be lower than the values typical for PCC.
文摘在不同温度下对高模低收缩 PET 工业丝进行拉伸性能测试,得到初始模量、断裂伸长率、强度、Lase—5、模量极小值E_(min)及相对应的伸长率ε_(min)等几个力学指标以及不同温度下的应力—应变曲线。通过分析得出:高模低收缩PET工业丝在实验温度下的拉伸为均匀拉伸,无细颈产生,力学性能随温度的上升呈下降趋势,但未出现急剧下降的现象。
