Influence of Carbonation on Mechanical Properties of Concrete

As one of the most important factors that determine the lifespan of a reinforced concrete structure, carbonation not only corrodes the reinforcing steel, but also changes the mechanical properties of concrete. For better understanding the performance of carbonated concrete structure, it is necessary to study the mechanical properties of carbonated concrete. The strees-strain relationship of carbonated concrete was analyzed on the basis of experiments. The specimens were made by means of accelerated carbonation and then compressed on the testing machine. Some very important characteristics of carbonated concrete were revealed by the testing results. In addition,a useful constitutive model of carbonated concrete, which proved to be suitable for analyzing carbonated concrete members, was established in this research.     

Analysis of interaction factors between two piles

A rigorous analytical method is presented for calculating the interaction factor between two identical piles subjected to vertical loads. Following the technique proposed by Muki and Sternberg, the problem is decomposed into an extended soil mass and two fictitious piles characterized respectively by Young＇s modulus of the soil and that of the difference between the pile and soil. The unknown axial forces along fictitious piles are determined by solving a Fredholm integral equation of the second kind, which imposes the compatibility condition that the axial strains of the fictitious piles are equal to those corresponding to the centroidal axes of the extended soil. The real pile forces and displacements can subequally be calculated based on the determined fictitious pile forces, and finally, the validity of the proposed approach and desired pile interaction factors may be obtained. Results confirm the portray the influence of the governing parameters on the pile interaction.     

应用两种不同数字图像分析法对沥青裹覆集料的检测与评价

集料与沥青的黏附性是影响道路耐久性最重要的因素之一。该文应用数字图像分析法估测沥青裹覆度替代人工预估法来评价黏附性。该方法为镜面反射量法,基于沥青反射光强度高于集料的特点,可用于估测所有颜色的集料。为了尽可能多地获取来自四分之一圆周弧形光源内的镜面反射量,随着旋转台的转动,拍摄不同角度的图像,并检测反射量用于估测沥青裹覆度。为了能够将研究结果与实际情况相比较,应用该方法对浅色集料进行评价,并与传统人工方法、评价浅色集料工作性优异的像素分割法进行比较。结果表明:传统人工方法离散性较大,难以准确估测;该方法测得的沥青裹覆度,接近像素分割法测值,但其值偏低;选取最优系数k的最小函数法计算补偿处理后,其与像素分割法测得结果没有明显差异。     

章学诚——我国倡议地方档案馆学说的先驱者

章学诚是我国档案支上最早倡议建立地方档案馆学说的先驱者。他的学说虽然没有被当时封建统治者所采纳，但他这种见解是有深远意义的。章学诚，号实高，清代浙江省绍兴府会稽人。生于公元1738年(乾隆三年)，卒于公元1801年(嘉庆六年)。     

饱和地基高频振动下孔压特性的数值分析

基于有效应力动力分析方法,采用FLAC2D的Byme体变孔压模型,分析饱和砂土地基在水平振动荷载作用下的孔压上升过程,分别考虑了振动频率为20、25、30和40 Hz 4种工况,初步总结了饱和砂土地基在不同频率振动处理后土体孔隙水压力分布的变化规律,分析地基孔压变化和振动频率之间的关系,以考察采用高频振动提高饱和砂土地基加固效果的可能性.     

我是档案员

节假日旧友重逢，同学相见，亲朋聚会，不时有离别数年当刮目相看之感：小时候的朋友如今腰缠万贯成了富翁，中学时的同学掌管一个大公司当了总裁，大学时的同窗有了私人小汽车……而我却依然故我——半瓶墨水、一支钢笔、两袖清风、“三尺兰台”、四间库房、五尺身材。     

谢远涵——被两个对立政权同时任命的省长

谢远涵,字敬虚,1875年(清光绪元年)出生在江西省兴国县长冈乡塘石村。其父谢静山,岁贡生,任教兴国县文澜书院。谢远涵随父读书,1891年考入县学。1893年考中光绪癸已科乡试举人。翌年又考中光绪甲午科进士。1895年(光绪二十一年),谢远涵在北京参加康有为联合入京18省举人的“公车上书”。他在策试中针对时弊,力主“变通”,甚得翁同和的赏识。这时他被翁同和预选派往日本去考察,因百日维新(即戊戌变法)失败而未成行。1898年,谢远涵任广东学台。谢远涵品行刚直,以其对嘉庆翰林萧朗峰在兴国县城为纪念前知县海公祠所出的上联可见。     

布衣危言之忠义之士——欧陽澈

欧阳澈,字德明,抚州崇仁人,出生在宋哲宗绍圣四年(公元1097年)。欧阳澈年少之时,就长着很多漂亮的须发,显得少年老成。为了取得功名,光宗耀祖,他很小就开始刻苦攻读儒家经典,准备科举考试。欧阳澈所读的书籍非常广泛,诸子百家著作、正史、野史,凡能搜集到手的书,也都尽量阅读,从不错过。他善于思考、勤于写作,著述达数十万字。然而,欧阳澈在入仕之途的科举考试中,却极不顺利,他多次参加考试,且将自己所著之书献上,均未能中第为官,始终是一介布衣。