圆竹标准材产业化发展路径

随着竹材应用领域的不断扩大,市场对圆竹材的需求逐年增加,然而较落后的竹材加工方式已成为制约竹材规模化、工业化利用的瓶颈,产业化发展圆竹标准材迫在眉睫。文章在结合中国竹资源分布特点和对圆竹材产业调研的基础上,系统分析了圆竹标准材制备、仓储体系构建、模块化构件加工及工程应用等环节的发展现状。文章认为,目前不完备的圆竹标准材生产和加工体系,制约了其产业链中上游资源的高效利用和下游产品的开发应用,应依据中国竹种的分布特点,规划实施圆竹材储备工程,建立圆竹标准材工业收储体系,推广圆竹标准材模块化应用,以加快圆竹标准材产业化发展。     

大跨度圆竹拱形结构建造技术——2019年北京世界园艺博览会竹藤馆案例分析

圆竹具有轻质高强、易于弯曲定型的特性,常用于建筑结构中,尤其是大跨度拱形结构这种具有曲线美感的建筑形式。文章以2019年北京世界园艺博览会竹藤馆为案例,通过实地考察和文献调研的方法,从原材料制备、建筑设计、节点构造、结构应力分散、拉结强化、装配式以及建筑健康监测等方面,综述了国内外较为经典的大跨度圆竹拱桥梁和建筑建造关键技术,分析了拱形建筑的受力特性以及圆竹材用于大跨度拱形建筑的材料适用性,提出标准圆竹材的应用在很大程度上延长了圆竹拱结构的寿命;构件预制化不仅降低了工程难度,还在一定程度上推动了竹建筑装配式进程;巧妙的节点构造和结构设计以及拉结强化均大大提高了竹建筑安全性;而后期健康监测和安全维护则进一步保证了大跨度圆竹拱建筑的安全性。本研究对圆竹标准材研究、圆竹拱形大跨度建筑技术体系建设、圆竹结构推广应用具有重要的学术参考价值,此外还具有重要的经济效益、社会效益。     

圆竹材套筒式钉接构件的抗弯性能研究

圆竹可作为结构材用于新型竹结构建筑。以不同径级的圆竹筒为原材料,采用大圆竹材套小圆竹材的套筒式镶嵌结合方式,辅以气钉枪钉接固定,制备连接件;并进行静力加载试验,分析其抗弯承载力和破坏形态,同时对圆竹管重要位点进行了应变测试。结果表明:套筒式钉接圆竹试件与完整的单根圆竹试件相比,抗弯强度和抗弯弹性模量分别降低了59.49%和18.68%。套筒式钉接圆竹试件的破坏模式多为连接接口处开始的纵向开裂,部分试件直钉孔处出现细缝。两组圆竹试件在弹性阶段的各测点应变均呈线性变化,且拉、压应变基本对称分布。套筒式钉接圆竹试件各测点应变相对于完整的单根圆竹试件略小。研究结果可为圆竹材工程应用提供参考依据。     

小径级圆竹家具用材力学性能及其设计改良研究

以毛竹、红竹和苦竹为研究对象,对其竹片、圆竹和圆竹不同部位的物理力学性能进行分析对比。研究表明:红竹和苦竹力学性能稍强于毛竹;竹材中部位置力学性能较优,可作为加工圆竹家具用材料。对局部注塑后圆竹力学性能变化的研究表明:注塑可大幅提高圆竹力学性能。根据力学性能变化情况及小径级圆竹特点,分别设计了直角斜接接合、三角并接接合、鱼口接合以及局部注塑后的圆竹丁字榫和偏心连接件连接方式;并将圆棒榫应用于圆竹家具部件接合部,使接合部性能更为优异。     

传统圆竹家具创新设计研究

随着家具品类增多,目前具有深厚文化底蕴的传统圆竹家具市场占有率较低,发展缓慢。针对此现象,研究了传统圆竹家具的结构特征,剖析了圆竹家具发展中面临的问题。结合可拆装结构、扁平化设计、材料混搭等方法,从设计的角度提出较为具体的创新设计方法和思路,以提高家具生产中材料利用率和生产效率,降低运输成本,同时更加适应现代审美需求。旨在拓宽圆竹家具市场,促进圆竹家具行业健康快速发展。     

圆竹家具结构创新设计

通过对圆竹家具和竹建筑结构形式的归纳与分析,提出采用新技术、新工艺创新设计圆竹家具结构形式;介绍了开发设计的两个系列共5种圆竹家具新型结构,期望以此提升圆竹家具产品的生产工艺、质量和档次。     

基于批量定制的圆竹家具减量化设计研究

为解决圆竹家具受生产技术的制约而导致产品同质化、附加值低等问题，运用批量定制理念，从优化产品结构、降低制造门槛的角度进行圆竹家具的减量化设计。首先，分析了批量定制对圆竹家具减量化的驱动因素：以定制的柔性化生产实现产品差异化、利用批量的规模化来促进产品的减量化，提出以标准化部件和适应性部件相互配合来实现圆竹家具减量化的思路。其次，展开了设计减量化、工艺减量化和包装减量化的具体策略研究。最后，针对圆竹家具减量化进行设计创新与实践，验证了从批量定制理念出发对圆竹家具进行减量化设计的可行性。     

圆竹填充节点抗拔性能研究

为高效、合理利用竹材资源,充分发挥圆竹优良的力学特性,针对因圆竹中空而造成的接合不便及强度不高问题,提出了用硬质木材局部填充圆竹内腔,提高圆竹构件间连接的可行性及强度。探讨了榉木直径、榉木与圆竹内腔间隙量、填充剂、填充剂木纤维添加量对圆竹节点抗拔力的影响。结果表明:1)当榉木直径接近圆竹内腔直径时节点的抗拔力较大,榉木与圆竹内壁间隙量过小或过大都会导致抗拔力下降,当间隙在1.5～3.5 mm时,抗拔力较高;2)石膏与脲醛树脂填充剂相比,后者的抗拔力明显高于前者;3)添加5%木纤维脲醛树脂填充剂节点的抗拔强度高于添加0%、10%木纤维的节点。研究结果可为圆竹家具设计提供理论依据。     

安吉县竹卵圆蝽在竹林中的种群动态模型及预测预报

为明确安吉县竹卵圆蝽(Hippotiscus dorsalis)的发生和危害情况,林间调查研究了安吉县竹卵圆蝽在竹林中的种群动态,并以历史资料和时间序列分析法ARIMA模块建立预测模型,并用2014-2015年数据进行模型验证评估。结果表明:竹卵圆蝽在整个发生期近现双峰倒M形的变化规律。观测点年单株最高虫口为83~254头,种群密度平均达34.5头/株,有虫株率在56.78%~97.65%间,上竹高峰日在4月13日至4月25日间,近3a竹卵圆蝽的上竹数量开始大幅增加。结果表明预测数据值与现实值误差在合理范围内,该模型的建立将为竹卵圆蝽的预测预报提供了科学依据。     

圆竹家具设计探究

圆竹家具在我国有着悠久的历史,具有丰富的人文内蕴,然而由于圆竹自身特性,造型和生产等方面受到限制,使圆竹家具难以适应现代人多样化的审美需求和工业化生产要求。笔者结合现代设计理念,对圆竹家具的特点和构造形式进行了深入分析,提出现代圆竹设计可以在生产过程上借鉴现代家具标准化统一生产,在外观造型上脱离传统的家具结构,精简家具构件,并且充分利用竹材韧性好等性能优势,突出造型美和材质美以满足现代审美需求;在连接结构上参考新材料或其他材料家具结构,在设计内涵上突出民族文化,引起情感共鸣。旨在为圆竹家具设计与制造提供理论指导,使圆竹家具设计符合现代生产和制造要求,满足消费者对家具外观造型的审美,达到消费者对圆竹家具情感的追求。     

竹类结构植物学研究进展

本文从竹秆、节部、叶、根、地下轴系统、胚胎等几个方面 ,对竹类结构植物学的研究进行了回顾 ,并对以后的工作进行展望。     

竹和藤的结构研究

竹子和藤在中国及邻近国家资源丰富，对其进行结构研究能更好地了解其特性，增加用途，生产出价值更高的产品。本文列举了几个最新的研究成果，如竹子的维管束类型，节间影响，竹鞭，竿基，作为能源库的淀粉，竹林老化及受伤反应等；藤的遗传分化，老化后的改性，商品化及聚事物浸渍提高质量等，竹子及藤的特性还需作进一步的研究。     

浙江竹材制板的现状分析

竹材通过加工制成的竹质人造板,不仅大量用作代木材料,而且有的竹质板力学强度很大,非木材所能比拟,是良好的工程结构材料。发展竹质板生产是克服木材短缺的切实有效途径。目前浙江竹质人造板主要种类有:竹材胶合板、竹编胶合板、竹篾胶合板、竹丝胶合板和竹材旋切片(板)五种。文章介绍了上述五种板的工艺流程、板的物理力学性质、主要用途,生产中存在的问题以及可供借鉴的国内外先进技术。     

菲律宾的竹子生产和研究现状

本文是林业部1987年赴菲竹子考察组的业务总结。菲已知竹种有11属55种,其中36种是直立型的,19种是攀援型的。8种竹种得到广泛应用,其中茨竹(Bambusa blumeana)分布最广,用途最大,是菲律宾最重要竹种。全菲竹林面积不清,估计直立型竹子面积在2万公顷以上。菲律宾气候炎热,雨量充沛,地形复杂,使丛生型、散生型、混生型竹种都有合适的生长区域,但热带型的丛生竹占主要地位。菲对发展人工竹林较为重视,采用的竹子繁殖方法包括种子育苗、鞭移栽、竹兜移栽、秆插、枝插、高压和平埋等等,裸根或带容器栽植,管理比较粗放。菲竹子主要用于渔业、香蕉业、建筑业、家具和手工业、船和筏。菲竹沙发和竹乐器精致,是菲竹子利用的一个特色。竹子改形技术较为成熟,竹子防蛀防腐较为重视。菲律宾竹子研究发展较快,有一批项目包括FAO资助项目正在研究。本文最后提出了几个值得借鉴的开发技术和管理措施。     

竹纤维*经济墙板初探

毛竹经鼓式削片机削片后用锤式打碎机加工成竹纤维。将竹纤维与采用同样工艺制备的针、阔叶木纤维进行纤 维形态对比，并用竹纤维取代木纤维作为混凝土骨科制备经济墙板。试验结果表明1)竹纤维形态优于木纤维；2)竹纤 维墙板可与针叶材纤维墙板媲美，且密度较低；3)用膨润土代替部分水泥可制备轻质经济墙板，轻质经济墙板的密度仅 为普通经济墙板的3／4，且强度及导热性能略优于普通经济墙板。     

Environmentally benign methods for producing green culms of ma bamboo (<Emphasis Type="Italic">Dendrocalamus latiflorus</Emphasis>) and moso bamboo (<Emphasis Type="Italic">Phyllostachys pubescens</Emphasis>)

The objective of this study was to find an effective method for treating ma bamboo (Dendrocalamus latiflorus) and moso bamboo (Phyllostachys pubescens) using new water-based reagents containing copper. The effects of green-color protection using various treatments on bamboo culms were examined in this study. Two methods were used: heating in a water bath and ultrasonic dipping. The results revealed that excellent green-color protection (a* value of −6.2) was obtained when ma bamboo culms were treated with 0.25% ammoniacal copper quaternary compound-type B (ACQ-B) in a water bath at 100°C for 2 h. It was also found that the wettability of bamboo epidermis increasedsignificantly after pretreatment in a mixture of 1% KOH and surfactant in a water bath at 100°C for 30 min. Furthermore, pretreated moso bamboo culms exhibited excellent green-color protection after they were treated with 0.25% ACQ-B at 100°C for 2 h (a* value of −8.2). This novel treatment method definitely endows the bamboo culms with a fascinating green skin color and consequently could increase the economic value of bamboo products. No improvement in green-color protection was found when ultrasonic energy was added to the water bath at ambient temperature.     

Green color protection of bamboo culms using one-step alkali pretreatment-free process

This study evaluated the protection effectiveness of alcohol-borne reagents for the green color of ma bamboo (Dendrocalamus latiflorus Munro) and moso bamboo (Phyllostachys pubescens Mazel). The results show that the types and concentrations of alcohol-borne reagents, the kinds of solvent, and the conditions of treatment greatly affected the green color of these two bamboo species. Without alkali pretreatment, an excellent green color protection (a* = −14.5) was obtained when the ma bamboo culms were treated with 0.5% methanol-borne copper chloride (CuCl₂) at 60°C for 30 min. Similar results were also obtained when ma bamboo culms were treated with 0.5% methanol-borne copper nitrate [Cu(NO₃)₂] at 60°C for 2 h (a* = −13.5). For moso bamboo, an attractive green color in the bamboo culms was achieved by treating the specimens with 1% methanol-borne copper acetate [Cu(CH₃COO)₂] at 60°C for 30 min. The a* value of treated specimens was −13.3. In addition, results demonstrated that ultrasonic treatment was more effective on green color protection than conventional water bath treatment. When moso bamboo was treated with 1% copper acetate at 60°C in an ultrasonic bath for only 15 min, a remarkable green color with an a* value of −13.6 was obtained on the bamboo epidermis.     

竹子在使用过程中的保护

Abstract:Bamboo culms are an excellent material for countless applications,Their wider use forconstruction is encouraged by the growing scarcity of timber.Since bamboo has a low natural resis-tance,protection against biological degradation is of vital importance for long term service.Protective measures without chemicals are preferable,but often limited In their effectiveness.When using preservatives,the restricted permeability of culm tissue,choice of preservative andtreatment method and environmental effects as well as economical aspects have to be considered.     

Sampling procedure for density estimation of bamboo galls induced by <Emphasis Type="Italic">Aiolomorphus rhopaloides</Emphasis> (Hymenoptera: Eurytomidae) in a bamboo stand

 To establish a sampling procedure for estimating the density of bamboo galls induced by Aiolomorphus rhopaloides Walker (Hymenoptera: Eurytomidae) in a stand of bamboo Phyllostachys heterocycla (Carr. Mitf.) (Monocotyledoneae: Gramineae), 5–12 bamboo culms were cut at random in late March of each year during 1998–2001 just before gall-maker emergence. The number of galls on the branches of each bamboo culm was counted. The spatial patterns of the galls on the culms in the stand and on the branches within each culm were measured by Iwao's patchiness regression. Galls were distributed contagiously both on culms and on branches. Current bamboo culms that emerged the previous summer did not require sampling because no galls were observed on them. Except for this, there was no difference in gall density on young and old culms, suggesting that it is not necessary to distinguish them. There were few (<4%) galls above 6 m height during the 4 years. There was no significant difference in gall density up to 4 m and above 4 m, suggesting that branches up to 4 m can be sampled with confidence. Kuno's two-stage sampling method at different precision levels showed that the number of culms to be sampled varied with gall density. For example, at mean density m = 1.0 per branch when the number of sampled branches per culm is 10, a total of 24 culms is required to estimate gall number at a precision level of D = 0.2, where D is the ratio of standard error to mean. Received: July 10, 2002 / Accepted: November 25, 2002 Acknowledgments I thank Dr. K. Kamijo for insect identification. Thanks are also due to the members of the Laboratory of Forest Protection for their kind help with the fieldwork. This study was supported in part by a Grant-in-Aid for Scientific Research (No. 11460068) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.