15CrMoR(H)钢配套焊材研制及其焊接接头性能研究

焊接是承压设备制造过程的关键环节,承压设备配套焊材性能对承压设备的制造质量起关键作用,决定承压设备的最终性能.研制了用于临氢环境的15CrMoR(H)用R307L焊条与H08CrMo(H)/JWF201(H)埋弧焊材,对其焊接工艺及熔敷金属性能进行了研究.特以焊接接头性能为主要指标,采取包括模拟封头热成型在内的多种热处理后,试验数据依旧保持了优异水平.分析焊接接头微观组织,其焊缝组织均为铁素体为主,有少量贝氏体和珠光体.     

燃烧法沥青含量测试仪测量不确定度评定

燃烧法沥青含量测试仪是混合料沥青含量分析的主要设备,根据试验方法可以有效测量混合料中沥青的含量,对混合料质量监控具有重要意义.燃烧法沥青含量测试仪检定主要参照JJG(交通)072-2006燃烧法沥青含量测试仪检定规程.本文通过分析,针对燃烧法沥青含量测试仪的温度示值误差、电子天平质量称重误差两个参数的测量不确定度进行了详细的分析和评定,对其他类似仪器测量不确定度评定有一定的参考意义.     

建筑企业"独生长尾"群体管理模式

本文以某建筑企业为例,基于"长尾理论"研究了独生子女群体中末尾人员(简称"独生长尾")令人不满意的工作现状并分析了原因,提出在数字化时代,"灰度管理"是更适合"独生长尾"的管理方式,用其所长避其所短能帮助其实现自我价值,成为对企业有贡献的人.     

改性油菜秸秆吸附材料对Cu(Ⅱ)的吸附

以油菜秸秆粉末为原料,分别采用甲醛-硫酸、戊二醛-硫酸、过氧化氢对其改性,得到生物质吸附材料。利用原子吸收分光光度计测定吸附后Cu(Ⅱ)溶液的吸光度,得出由甲醛-硫酸、戊二醛-硫酸改性的油菜秸秆吸附效果相对更好。进而以戊二醛-硫酸改性后的油菜秸秆作吸附材料,改变实验条件,结果表明,在25℃、振荡20 min,其对Cu(Ⅱ)的吸附效果最好,达到95. 87%。     

Advances in statistical mechanics of rock masses and its engineering applications

To efficiently link the continuum mechanics for rocks with the structural statistics of rock masses,a theoretical and methodological system called the statistical mechanics of rock masses(SMRM)was developed in the past three decades.In SMRM,equivalent continuum models of stressestrain relationship,strength and failure probability for jointed rock masses were established,which were based on the geometric probability models characterising the rock mass structure.This follows the statistical physics,the continuum mechanics,the fracture mechanics and the weakest link hypothesis.A general constitutive model and complete stressestrain models under compressive and shear conditions were also developed as the derivatives of the SMRM theory.An SMRM calculation system was then developed to provide fast and precise solutions for parameter estimations of rock masses,such as full-direction rock quality designation(RQD),elastic modulus,Coulomb compressive strength,rock mass quality rating,and Poisson’s ratio and shear strength.The constitutive equations involved in SMRM were integrated into a FLAC3D based numerical module to apply for engineering rock masses.It is also capable of analysing the complete deformation of rock masses and active reinforcement of engineering rock masses.Examples of engineering applications of SMRM were presented,including a rock mass at QBT hydropower station in northwestern China,a dam slope of Zongo II hydropower station in D.R.Congo,an open-pit mine in Dexing,China,an underground powerhouse of Jinping I hydropower station in southwestern China,and a typical circular tunnel in Lanzhou-Chongqing railway,China.These applications verified the reliability of the SMRM and demonstrated its applicability to broad engineering issues associated with jointed rock masses.     

Treatment Methods for the Quality Improvement of Recycled Concrete Aggregate (RCA)–A Review

For the purpose of providing references for further research and practical application about the quality improvement of RCA,in this paper,various treatment methods were firstly classified into four categories:removing old mortar (OM),strengthening OM,multi-stage mixing methods,and combination methods.Thereafter,the improvement mechanisms and important conclusions of various treatment methods were elucidated and summarised respectively.In the section of discussion,the improved effects as well as advantages and disadvantages of various treatment methods were compared and discussed respectively,and recommendations for the selection of treatment methods were proposed.Finally,the further research directions were pointed out,and an integrative programme on the quality improvement of RCA was recommended.