Evaluation on the Application of GLB Structures

Glued Laminated Bamboo (GLB) is one kind of composite material;the use of GLB in structural engineering can reduce the demand for wood, a possible solution to relieve the damage to natural forest. With the help of the design and construction experience of timber structures, a new type of building structure: bamboo structure is introduced. This paper presents a comprehensive review on the study of GLB and bamboo structure. Some important physical, mechanical, and chemical properties such as seismic performance, fire resistance, and energy consumption are discussed. In addition, the property of bamboo composites, the failure mode of GLB beam and columns are also analyzed. This paper also pointed out the problems faced by the development of bamboo structure, which can be a suggestion for subsequent research. In general, GLB is a green and environmentally-friendly structural material and the development of bamboo structure provides another choice to conform the concept of sustainable development.

Evaluation of Physical and Mechanical Properties of Glued Bamboo:A Review

The use of glued bamboo(GB)in structural engineering is growing interest in the construction industry,as it is a kind of natural material with strong regenerative ability.In addition,the utilizing of GB can reduce the demand for concrete,a possible way to decrease the destruction to natural environment and the consumption of fossil energy.This paper presents a comprehensive analysis on the properties of GB based on the experimental data available in the published researches.Some important physical,mechanical,and chemical properties of GB are discussed.It can be concluded that,at present,more emphasis has been given to study the mechanical property and gluing performance of GB.By analyzing existing research results,this paper provides some recommendations for future research.

超算云屋盖交叉钢桁架施工关键技术

雄安超算云项目结构造型新颖,空间关系复杂,屋盖下部楼板错层,安装方案的选择和支撑布置难度大,需选择合理支撑卸载顺序保证结构卸载安全。屋盖钢结构采用斜向交叉网格桁架结构体系,桁架弦杆相互斜交,网格桁架西侧呈弧形向下延伸交于封边梁,再通过变截面弧形弯扭V型支撑将屋盖荷载传递给下部框架,网格桁架东侧与立体拱桁架连接,跨中布置少量的圆钢管柱,形成大跨空间结构。运用深化设计技术对大跨结构进行节点优化设计,使弯扭V型支撑加工后满足结构传力及建筑造型的需求。根据项目结构体系及布置特点,通过对提升方案、滑移方案和吊装方案等三种方案的支撑体系、施工难易程度、安全管理难度、进度及施工成本的横向对比分析,选择最优的分段原位吊装方案。东侧立体拱桁架根据结构构造,将拱形桁架合理拆分成上下两榀桁架,下一榀桁架设置支撑分段安装定位,同时下一榀桁架提供支点支撑上一榀桁架,解决了拱形桁架高度高、重量大而难以安装的施工难题。对大跨斜交网格桁架进行合理分段划分,设置多跨门式支撑体系,采用塔吊分段安装屋盖交叉网格桁架,并采用交叉稳定杆进行结构安装过程中的临时固定,解决了网格桁架单片安装过程中的平面外稳定的施工难题,保证了桁架结构安装精度。多台塔吊从屋盖结构角部向核心区推进的安装顺序,既解决了每一步安装均能形成临时稳定体系确保施工安全,又能多机同步安装提高施工进度,为其他大跨桁架结构安装提供参考。运用有限元分析软件MIDAS/Gen,计算温度应力对大跨交叉网格结构卸载的影响,对大跨交叉桁架是否考虑温度应力和卸载方向的不同组合进行多工况卸载模拟分析对比,分析结构最大应力与最大变形的应力、应变云图。通过模拟计算研究表明,多支点大跨交叉桁架卸载需要考虑温度应力的作用,并采取从变形较大的跨中向支座卸载的顺序,卸载时结构温度应与结构安装时温度接近,减小结构施工温度变化引起的应力,保证结构施工安全。