Sensitivity study of the finite element model for wood-framed shear walls

A sensitivity study was performed with a nonlinear elastic finite element model for monotonie analyses of wood-framed shear walls. The objective was to provide information about simplifying a model of wood-framed shear walls with no significant loss in accuracy. The simplifications concern features such as slips in joints between frame members, slips in hold-down connections, and bearing between adjacent sheathing panels. The results from analyses of a shear wall with an opening of window shape show that the effect of constraint by the bearing between sheathing panels and slips in frame joints on the overall stiffness of the wall is limited. Thus, there are great possibilities for reducing the calculation time by not taking these phenomena into account, avoiding an excessive number of degrees of freedom and iterations. The influence of the simplifications on the distribution of vertical reaction forces along the wall is more significant. Furthermore, if each simplification is introduced separately, the effect on the overall stiffness is greater. The difference, however, is less than 10%. The failing pattern of the nail connections is also clearly influenced by the simplifications when they are introduced separately. The results from the analyses show that slips in frame joints can be sufficiently represented by those in connection with the opening.     

松花粉破壁方法的比较研究

以松花粉为主要原料,分别采用纤维素酶法、超声波法、发酵法和旋风破碎法对松花粉进行了破壁研究,并从不同角度对几种方法进行了比较。     

AN EXPERIMENTAL STUDY OF THE ASEISMATIC BEHAVIOUR OF WIDE-SHALLOW COUPLING BEAMS

This paper presents the experimental results of 9 specimens.The mainobject of this experiment is to study the aseismatic behaiour of wide-shallowcoupling beams.Several variables that exert main influence on the behaviourare considered.Also,some aspects concerning the specific design are proposed.     

宿迁市宿城地区半地下土墙日光温室的生产现状 问题与对策

对宿迁市宿城区半地下土墙日光温室基地的生产现状进行了详细了解,并分析了其发展优势和存在的隐患,进一步提出了相应的发展对策。     

龙江建筑幕墙浅析

建筑幕墙作为一种建筑外围护结构为现代建筑更多采用。它即具有幕的性质,又具有墙的功能笔者认为很有必要加速发展幕墙设计施工监理队伍。     

刚度有突变的弹性支承剪力墙分析

The present paper is the extension of a previous one on shear walls~[1]. Elastic supports are replaced by a story of walls with equivalent flexural stiffnesses. The wall stresses are then analyzed on the assumption that all the walls subjected to lateral     

Factors that contribute to the mycoparasitism stimulus in Trichoderma atroviride strain P1

Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonis…     

新型砌块墙体裂缝的成因及防治

用新型砌块砌筑的墙体发生裂缝,是我国墙体材料革新后产生的一种新的质量通病,已引起人们的重视,本文就墙体发生裂缝的原因及防治措施进行了分析和探讨。     

配筋混凝土砌块砌体剪力墙位移延性设计方法

提出了配筋混凝土砌块砌体剪力墙基于位移延性的设计方法．通过对两片不同长度的矩形配筋混凝土砌块砌体剪力墙墙肢的计算分析，研究了轴压比、高宽比、配筋率和灌孔率对墙体受力性能的影响，结果表明上述几种因素对配筋混凝土砌块砌体剪力墙结构的延性性能起着重要的作用．提出了配筋混凝土砌块砌体剪力墙结构位移延性比的计算方法和配筋混凝土砌块砌体剪力墙弹塑性层间位移角限值1／300的建议，供设计时参考．     

Exploring the use of edible and evergreen perennials in living wall systems in the Scandinavian climate

We have performed a field experiment to investigate the survival and vitality of perennial plants in a living wall installed in an industrial area in Malmö, southern Sweden. The main aim of the study was to investigate the possibility of growing edible and evergreen perennial plants in living wall systems in the Scandinavian climate. We conclude that the edible perennial plants Allium schoenoprasum, Calamintha nepeta, and Fragaria vesca are feasible in living wall systems in the Scandinavian climate. Thymus vulgaris is sensitive to the Scandinavian climate, and performed equally poorly in Rockwool panels and in soil-filled containers (controls). We also conclude that the evergreen perennial plant species Chamaecyparis pisifera, Euonymus fortuneii, Euphorbia polychroma, Vinca minor, and Waldsteinia ternata can be grown in green walls, and that the edible evergreen plant Vaccinium vitis-idea is highly suitable for living walls in this climatic region. A. schoenoprasum, C. pisifera, E. fortuneii, I. crenata, L. sylvatica, V. minor, and V. vitis-idea showed 100% survival rates, however, the visual quality of e.g. I. crenata and L. sylvatica was not acceptable for ornamental purposes.