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12th International Conference on Advances in Steel-Concrete Composite Structures (ASCCS 2018)

第十二届钢-混凝土复合结构研究进展国际会议(ASCCS 2018)

Universitat Politècnica de València, València, Spain, June 27-29, 2018

6月27日至29日，西班牙巴伦西亚理工大学

Doi: http://dx.doi.org/10.4995/ASCCS2018.2018.7220

Steel Concrete Composite Systems for Modular Construction of High-rise Buildings

高层建筑模块化钢-混凝土组合体系

J. Y. R. Liew(a,b*), Z. Dai(a) and Y. S. Chua(a)

a Department of Civil and Environmental Engineering, National University of Singapore, Singapore

新加坡国立大学土木及环境工程学系，新加坡

b College of Civil Engineering, Nanjing Tech University, Nanjing, China

南京工业大学土木工程学院，南京，中国

* corresponding author, e-mail address: ceelyj@nus.edu.sg

Abstract摘要

Modular construction has gained popularity and attention particularly in low-rise building lately due to its numerous advantages: faster construction speed, better quality control, reduction in work force and construction waste, etc. This innovative technology promotes off-site manufacturing of modular units and on-site assembly, improving the construction efficiency and productivity. However, modular construction is not commonly used in highrise buildings because of the joints’ flexibility as well as manufacturing and construction tolerance, which have significant impact on the overall stability of the building. This paper highlights the existing challenges of modular construction of high-rise buildings and provide several options to address these challenges. Firstly, the weight of a module is constrained by the transportation and lifting crane capacities. For this reason, lightweight concrete is introduced together with structural steel section to form lightweight steelconcrete composite system to reduce the weight of the module without compromising the strength and stiffness. Secondly, to speed up the site assembly of modular units, special joints are developed to resist the forces due to gravity and horizontal loads. Fast and easy joining techniques with acceptable tolerance control are essential to ensure the structural integrity and stability of the building. Finally, the innovation for productivity can be maximized by implementing automation technologies in the manufacturing and construction of the modular units.

模块化施工因其具有施工速度快、质量控制好、减少劳动力、减少建筑浪费等诸多优点，近年来在低层建筑中得到了广泛的应用和重视。这一创新技术促进了模块化单元的异地制造和现场组装，提高了施工效率和生产率。然而，模块化结构在高层建筑中并不常用，因为其节点的灵活性以及制造和施工的公差对建筑的整体稳定性有着重要的影响。本文着重阐述了高层建筑模块化建设面临的挑战，并提出了解决这些挑战的几种方案。首先，模块的重量受到运输和起重能力的限制。为此，在不影响模块强度和刚度的前提下，将轻量化混凝土与结构型钢组合形成轻量化钢混凝土组合体系。其次，为了加快模块化单元的现场装配，开发了特殊的关节来抵抗重力和水平载荷的力量。快速和容易的连接技术与可接受的公差控制是必不可少的，以确保结构的完整性和稳定性的建筑物。最后，通过在模块化单元的制造和构造中实施自动化技术，可以最大限度地提高生产率。

Keywords: Modular construction; Composite design; Lightweight concrete; Fast Joint; High-rise building.

关键词:模块化建设;组合设计;轻质混凝土;快速接头;高层建筑。

1. Introduction

Conventional construction methods such as cast in-situ structural elements and brick walls are still widely used at present due to the financial feasibility of such construction methods with relatively low labor cost in some countries. This has been highlighted to be one of the factors which impedes the growth in construction productivity [1]. At the same time, the exploding population and the unprecedented urbanization call for more high-rise buildings.

传统的施工方法，如现浇结构构件和砖墙，目前仍被广泛使用，因为在一些国家，这种施工方法的经济可行性和劳动力成本相对较低。这已被强调为阻碍建设生产力[1]增长的因素之一。与此同时，人口爆炸和前所未有的城市化需要更多的高层建筑。

Coincidently, a good design practice of high-rise buildings is to embrace simplicity, standardization, repetition, and economy of scale. This renders the high-rise buildings intrinsically modular [2].

巧合的是，一个好的高层建筑设计实践是简单、规范、重复和规模经济。这使得高层建筑本质上是模块化的[2]。

To overcome these challenges, modular construction has been encouraged in Singapore whereby building modules are constructed offsite before being assembled on-site to form a building. Prefabricated Prefinished Volumetric Construction (PPVC) is a specific type of modular construction where the internal elements of the module (walls, floors and ceilings etc.) are prefinished before the modules are assembled. With the advantages of higher construction speed, productivity and quality control, PPVC has been adopted in many sectors of the building industry, such as residences, hotels and hospitals by many countries over the last 20 years. In recent years, Singapore Building and Construction Authority (BCA) has also shown great effort to promote PPVC in local projects to achieve a productivity improvement in terms of construction time and manpower up to 50%. 

为了克服这些挑战，新加坡鼓励模块化建设，在现场组装成建筑之前，建筑模块先在场外建造。预制预制体结构(PPVC)是一种特定类型的模块化结构，其中模块的内部元素(墙壁、地板和天花板等)在模块组装之前进行了预制。PPVC具有施工速度快、生产率高、质量控制好等优点，在过去的20年里被许多国家的住宅、酒店、医院等建筑行业广泛采用。近年来，新加坡建筑及建造局(BCA)亦致力推广本地项目的公私合营，务求在建造时间及人手方面，提高生产力至百分之五十。

Since 2014, the use of PPVC in selected public residential projects has been made mandatory [3]. The benefits of PPVC has been proven in the successful launching of pioneer PPVC projects in Singapore: (a) Crowne Plaza Hotel Extension, Changi Airport, and (b) NTU North Hill Residence Hall as shown in Fig. 1. It is reported that both projects have achieved time savings of up to 6 months and on-site manpower savings of up to 40 %. These projects give confidence to the industry, government, and general public on this new technology. Due to the supportive government, it is projected that by 2019, 35% of newly launched housing board projects will be built using PPVC.

自2014年起，在选定的公共住宅项目中使用PPVC已成为强制性的[3]。PPVC的好处已经在新加坡的先驱PPVC项目的成功启动中得到了证明:(a)皇冠假日酒店扩建、樟宜机场和(b)南洋理工大学北山宿舍楼，如图1所示。据报道，这两个项目都节省了多达6个月的时间，现场节省了高达40%的人力。这些项目给了行业、政府和公众对这项新技术的信心。由于政府的支持，预计到2019年，新启动的住房委员会项目将有35%使用PPVC建造。

Fig. 1. Pioneer PPVC projects in Singapore (a)Crowne Plaza Hotel Ext @ Changi Airport,and (b) NTU North Hill Residence Hall.

PPVC concept appears to be compatible with high-rise building which encourages design standardization and repetition. Nonetheless, it is not so commonly used in high-rise buildings because of its novel structural form, joints’ flexibility as well as manufacturing and construction tolerance, which have significant impact on the overall stability of the building. The continuity of the beam-column frame is uncertain and the reliance on lateral resisting system is essential especially for high-rise buildings, which are commonly found in Singapore. Therefore, this paper highlights the existing challenges of modular construction of high-rise buildings and provide several options to address these challenges.

但由于其新颖的结构形式、节点的柔性以及制造和施工的耐受性，对建筑的整体稳定性有着重要的影响，因此在高层建筑中并不常用。梁柱框架的连续性是不确定的，特别是在高层建筑中，梁柱框架必须依赖抗侧力系统，这在新加坡是很常见的。因此，本文强调了高层建筑模块化建设存在的挑战，并提出了解决这些挑战的几种方案。

2. Modular construction as solution模块化建筑的结构方案

There are two types of PPVC module systems with different types of load path. Load-bearing wall module are commonly found in concrete building, whereby the concrete walls are used to transfer gravity loads to the foundation, as well as resisting the lateral loads as displayed in Fig.2. On the other hand, Fig. 3 shows cornersupported module, which is generally made of steel or steel-concrete composite material, in which the gravity loads are transferred to edge beams to the columns and foundations.

PPVC模块系统有两种不同的加载路径。承重墙模块在混凝土建筑中较为常见，利用混凝土墙体将重力荷载传递到基础上，抵抗侧向荷载，如图2所示。另一方面，图3所示为角支撑模块，该模块通常由钢或钢-混凝土复合材料制成，其中重力荷载被转移到边缘梁到柱和地基上。

Generally, the weight of a steel modular unit is about 15 to 20 tonnes, which is relatively lighter than a concrete modular unit with weight of about 20 to 35 tonnes. 

一般而言，钢组件的重量约为15至20公吨，较重量约为20至35公吨的混凝土组件为轻。

Moreover, steel modular system has more flexibility in architectural design due to its open space frame and larger modular size. The construction speed of steel modular system is also faster as it commonly involves bolted connection whereas concrete modular system often requires in-situ grouted connection. Nonetheless, steel modular construction may experience durability issues that require additional measures to address issues realted to corrosion and fire. For these reasons, steel PPVC systems are commonly used in institutional and commercial buildings,whereby open space are necessary. On the other hand, concrete PPVC systems are preferable in residential buildings due to better durability and ease of inspection.

此外，钢模块化系统由于其开放的空间框架和较大的模块化尺寸，在建筑设计中具有更大的灵活性。钢模块系统通常采用螺栓连接，而混凝土模块系统通常采用现场灌浆连接，因此钢模块系统的施工速度也比较快。尽管如此，钢模块结构可能会遇到耐久性问题，需要额外的措施来解决与腐蚀和火灾有关的问题。由于这些原因，钢PPVC系统通常用于公共机构和商业建筑，因此开放空间是必要的。另一方面，混凝土PPVC系统由于具有更好的耐久性和易于检测，在住宅建筑中更受欢迎。

Fig. 2. Load bearing modular system.

Fig. 3. Corner supported modular system.

3. Challenges in high-rise modular construction高层模块化结构的挑战

This paper focuses on steel modular construction because of its high potential in improving construction productivity and higher performance to weight ratio. There are many challenges in high-rise modular construction because the building is constructed by stacking up the modules, connecting them together using joints. 

由于钢结构模块化结构在提高施工生产率和提高性能重量比方面具有巨大的潜力，因此本文重点研究钢结构模块化结构。在高层模块化建设中存在许多挑战，因为建筑是通过堆叠模块来建造的，并使用关节将它们连接在一起。

Firstly, the weight and size of a module are constrained by the transportation and lifting capacities [4]. Furthermore, the joint design is critical to ensure the robustness and continuity of the structural modules with redundant load paths. As the modules are prefabricated off site and assembled on site, the manufacturing and construction tolerances are essential to prevent accumulative error during the module stack-up.To address these challenges, several options are discussed below.

首先，模块的重量和尺寸受到运输和起重能力[4]的限制。此外，节点设计对于保证具有冗余荷载路径的结构模块的稳定性和连续性至关重要。由于模块是现场预制和现场组装的，制造和施工公差对于防止模块堆叠过程中累积误差至关重要。为了解决这些挑战，下面讨论几个选项。

3.1. Lightweight modular unit轻量级的模块化单元

Logistics for modules transportation from factory to site affects the maximum size and weight of each module design, which in turn affects the number of modules to complete the layout design. The size of a typical modular unit should be kept within the local authority’s regulatory without requiring additional treatment such as police escort. 

模块从工厂到现场的物流运输影响到每个模块设计的最大尺寸和重量，进而影响到完成布局设计的模块数量。一个典型的模块化单位的大小应保持在地方当局的监管，不需要额外的处理，如警察护送。

For instance,Land and Traffic Authority in Singapore requires that the width of the module should be less than 3.4 m while the maximum height of the module is restrained to 4.2 m as depicted in Fig.4 to avoid clashing with overhead bridges regulatory. Secondly, the lifting of modules during stacking and assembly also constrains the weight of a modular unit. According to local consultants, most PPVC projects in Singapore use lifting cranes with up to 20 tonnes capacity while only a few projects can reach 35 tonnes as the lifting crane price shoots up significantly when its capacity goes beyond 20 tonnes. Therefore, hoist weight and transportation size are critical challenges in PPVC.

例如，新加坡国土交通管理局要求模块宽度小于3.4米，而模块的最大高度限制在4.2米，如图4所示，以避免与架空桥监管发生冲突。其次，在堆垛和组装过程中，模块的升降也制约了模块的重量。根据当地咨询公司的说法，新加坡的大多数PPVC项目使用的起重吊车最多可达20吨，而只有少数项目能达到35吨，因为当起重吊车的运力超过20吨时，吊车价格会大幅上涨。因此，提升机的重量和运输尺寸是PPVC面临的关键挑战。

Fig. 5 shows typical weight distribution in a steel modular unit [5]. It is observed that the two largest components that contribute to weight are floor material and steel weight. Thus, composite design can be used in PPVC in order to reduce the steel usage owing to increased stiffness of the system, thus composite slab and beam design is attempted for the replacement of existing steel structure in order to reduce floor weight and increase performance [6]. Other than reducing the weight, this design allows larger headroom in a PPVC unit. This is an important aspect in PPVC design because of its double slab system (e.g. floor and ceiling) that reduces the available headroom. The weight of a modules can be further reduced by using lightweight concrete in the slim floor system. Additionally, lightweight partition wall can be incorporated in the PPVC system because they are for non-structural purpose but require good acoustic and fire protection. 

图5显示了钢模块单元[5]的典型重量分布。据观察，造成重量的两个最大的组成部分是地板材料和钢的重量。因此，在PPVC中可以采用组合设计，由于系统刚度的增加，可以减少钢材的使用量，因此可以尝试采用组合板梁设计来代替现有的钢结构，以减少楼板重量，提高性能[6]。除了减轻重量，这种设计允许更大的净空在PPVC单位。这是PPVC设计中的一个重要方面，因为它的双层板系统(如地板和天花板)减少了可用的净空。在超薄地板系统中采用轻质混凝土可以进一步减轻模块的重量。此外，轻质隔墙可以纳入PPVC系统，因为它们用于非结构目的，但需要良好的隔音和防火保护。

Hoisting weight can be further reduced by using composite design in column such as rectangular concrete-filled tubular column. This is due to weight of concrete cast-in situ is not included in hoisting weight and thus, by separating the infill concrete weight and steel weight, aim of reducing hoisting weight can be achieved.

在矩形钢管混凝土柱等柱中采用组合设计，可进一步减轻吊装重量。这是由于在现场浇筑的混凝土重量不包括在吊装重量中，因此，通过将填充的混凝土重量与钢重量分离，可以达到降低吊装重量的目的。

Fig. 4. PPVC module size limit due to transportation truck.

Fig. 5. Weight distribution in a steel modular unit [5].

3.2. Fast-installed jointing techniques快速连接技术

Joint design in modular construction aims for fast and easy installation yet able to provide sufficient resistance. As shown in Fig. 6, all the steel members are connected using welded connections within a steel module. Beam-tocolumn joints can usually be treated as rigid connection when full strength butt welds are used. Since there are no guidelines in designing such joints, numerical analysis and experiments are usually needed to confirm its rigidity [7].

模块化结构中的接头设计旨在快速、方便地安装，同时又能提供足够的阻力。如图6所示，所有的钢构件都采用钢模块内的焊接连接方式连接。当采用全强度对接焊时，梁柱节点通常可视为刚性连接。由于此类节点的设计没有指导原则，通常需要通过数值分析和实验来确定其刚度[7]。

Corner-supported modules are connected with adjacent modules via beams and columns as shown in Fig. 6. Just like conventional frame structures, joints of steel PPVC buildings can be classified as corner joints J1, perimeter joints J2,and internal joints J3. Different joints have different connection details and thus have different structural performances and loading conditions.

角支撑模块通过梁和柱与相邻模块连接，如图6所示。与传统的框架结构一样，PPVC钢结构的节点也可分为角节点J1、周节点J2和内节点J3。不同的节点具有不同的连接细节，因而具有不同的结构性能和加载条件。

Fig. 6. Assembled modular steel frame.

Steel PPVC units typically are designed to be abutting the core wall. In other words, public spaces (corridors) are included in steel modules which have lighter weight and can span up to 16m subject to regulation of road transportation.

钢PPVC单元通常被设计成与核心墙毗连。换句话说，公共空间(走廊)包括在钢模块中，重量更轻，跨度可达16米，符合公路运输规则。

With this advantage, core wall and foundations can be constructed first while steel modules are being manufactured in the factory. The speed of construction is much faster than the system where cast in-situ corridors are used.

有了这一优势，核心墙和基础可以先建造，而钢模块正在工厂制造。施工速度比采用现浇回廊的系统快得多。

Using pure steel modules in high-rise PPVC system will make the column sizes to be large or thicker steel section, and thus will lead to higher costs and less usable space. For example, in the world’s tallest PPVC building, a 32-story braced steel PPVC systems (B2 Tower) in New York,column sizes were kept to be 150 x 150 mm but the thickness of steel was up to 38 mm [8].

在高层PPVC系统中使用纯钢模组，会使柱型尺寸变大或型钢截面变厚，从而导致成本增加和使用空间减少。例如，在世界上最高的PPVC大楼，纽约的32层支撑钢PPVC系统(B2塔)，柱子尺寸保持为150 x 150毫米，但钢的厚度达到38毫米[8]。

Variations of column sizes along the height of PPVC buildings will also lead to difficulties in module-to-module connections. Thus, using composite column design by keeping the column sizes while changing the infill concrete grades can be an ideal solution.

柱子尺寸随PPVC建筑高度的变化也会导致模块间连接的困难。因此，通过保持柱的尺寸同时改变填充混凝土的等级来设计组合柱是一种理想的解决方案。

A joining technique (bolted beam-beam connection) that joins the floor beams of the upper module and ceiling beams of the lower module using bolted connection, as shown in Fig. 7, has been studied by many researchers and designers over the world. According to Chen et.al [9] and Lee et. al [10], bolted beam-beam connections can be used in steel PPVC structures and can be designed to be ductile and strong enough to resist seismic loadings. However, this connection is very stringent on manufacturing tolerances. Large number of bolts usually leads to challenges in bolting. In addition, to perform bolted connections, entering the prefinished modules and access holes on walls, floors or ceilings are necessary at every corner of the modules. This will cause potential damages to internal finishes and costly rework on site.

根据Chen et.al[9]和Lee et.al[10]，螺栓连接的梁-梁连接可用于钢PPVC结构，其设计具有足够的延性和足够的强度来抵抗地震荷载。然而，这种连接对制造公差非常严格。大量的螺栓通常会导致螺栓紧固的挑战。此外，为了进行螺栓连接，在模块的每个角落都需要进入预制模块和墙壁、地板或天花板上的检修孔。这将导致潜在的损害内部完成和昂贵的现场返工。

Moreover, in Singapore, 100% wall finishes are required [3]. Therefore, bolted beam-beam connection may not be idealised for steel PPVC structures in Singapore.To solve the above issues, another type of joining technique that allows for connections to be made outside the modules. It typically utilizes threaded bars (or reinforcements) to connect the columns together as shown in Fig. 8. However,there are also several problems. Firstly when each column is connected vertically through more than one threaded bars, installation becomes very difficult since there are at least four columns of one module. Secondly, if only one threaded bar is to be used, the axial and moment resistance of such connection is very low [11]. As a result of this, the frame action will be weak and lateral deflection of the global system will be large and thus not suitable for high-rise building.

因此，对于新加坡的PPVC钢结构而言，螺栓梁梁连接可能并不理想。为了解决上述问题，另一种连接技术允许在模块外部进行连接。它通常使用螺纹杆(或加强件)将柱连接在一起，如图8所示。然而，也有几个问题。首先，当每一列通过多个螺纹杆进行垂直连接时，安装变得非常困难，因为一个模块至少有四列。其次，如果只使用一根螺纹杆，则这种连接的轴向阻力和弯矩阻力都很低。因此，框架的作用将是薄弱的和横向偏转的全球系统将是大的，因此不适合高层建筑。

参考阅读：轻钢笔记《模块化装配式建筑产品开发》

参考阅读：冷弯薄壁型钢体系综合应用案例《模块化集成房屋-制造篇》

参考阅读：冷弯薄壁型钢体系综合应用案例《模块化集成房屋-吊装篇》

Fig. 7. Typical beam-beam connection (a) VectorBloc System (Bowron, 2016), (b) Corner Joint J1 (Mao,2017), (c) Perimeter Joint J2 (Lee et al., 2017), and (d) Interior Joint J3 (Chen et al., 2017).

图7所示。典型的梁-梁连接(a)向量集系统(Bowron, 2016)， (b)角节点J1 (Mao,2017)， (c)周边节点J2 (Lee等人，2017)，和(d)内部节点J3 (Chen等人，2017)。

Fig. 8. Module-to-module connection using single rebar.

图8所示。模块到模块的连接使用单一钢筋。

In summary, for high-rise steel PPVC system,there has not been a good joining technique that can allow for ease of installation and can yet provide high structural resistance. A new joining technique shall be developed to tackle such issues. In addition, it has been concluded by many researchers that most PPVC joining module-to-module connections are semi-rigid [9, 10, 12]. How will the semi-rigidity affect the global performances of the structure should be studied.

综上所述，对于高层钢结构的PPVC系统，目前还没有一种良好的连接技术，可以方便的安装，同时又能提供较高的结构抗力。应该开发一种新的连接技术来解决这些问题。此外，许多研究人员已经得出结论，大多数PPVC连接模块到模块的连接是半刚性的[9,10,12]。研究半刚性对结构整体性能的影响。

3.3. Automation technologies自动化技术

At current practice, the productivity and efficiency of PPVC are not fully maximized yet because there are still many manual labour work involved in the factory as well as at construction site. This is because the initial investment cost in automation technologies is too high and the support from local authority is lacking. 

在目前的实践中，PPVC的生产率和效率还没有完全最大化，因为在工厂和施工现场仍然有很多体力劳动。这是因为自动化技术的初始投资成本过高，缺乏地方政府的支持。

The manufacturing of modular unit in factory are sometimes still involved conventional panelized casting, followed by assembly of panels into modular unit. This causes error in verticality and horizontality of the module as well as water leakage problem. These problems will lead to many problems during on-site assembly.

在工厂中，模块化单元的制造有时仍然涉及传统的镶板铸造，然后将面板组装成模块化单元。这导致了模块的垂直和水平方向的误差以及漏水的问题。这些问题会给现场装配带来很多问题。

On the other hand, due to lack of automated machines at construction site, longer time is required to adjust the lifting chains such that the modules is stable before assembly. 

另一方面，由于施工现场缺少自动化机械，需要更长的时间来调整升降链，使模块在装配前保持稳定。

Poor design of lifting frame that leads to unstable module as displayed in Fig. 9 during lifting might causes damage of internal finishes of modules especially in PPVC whereby the modules are completed with finishes. This is also caused by many lifting chains in the lifting frame, as depicted in Fig. 10,and all the chains are adjusted manually.Furthermore, at current practice, the locating of module during assembly is still conducted manually as displayed in Fig. 11.

如图9所示，由于提升架设计不当，导致模块在提升过程中不稳定，可能会导致模块内部饰面损坏，特别是在PPVC中，模块是用饰面完成的。如图10所示，这也是由于升降架上有很多升降链，所有的链条都是手动调节的。此外，在目前的实践中，装配过程中的模块定位仍然是手工进行的，如图11所示。

Fig. 9. Unstable module during assembly [13].

Fig. 10. Lifting of concrete PPVC module [14].

Fig. 11. Locating the module.

Nonetheless, it is expected that conventional cast in-situ method will be increasingly being replaced with modular construction, where building components such as columns, slabs and even larger volumetric elements like entire rooms are manufactured off-site in controlled environment. Like other industries, automation is becoming more widespread in construction.

尽管如此，预计传统的就地浇铸法将越来越多地被模块化结构所取代，在这种结构中，诸如柱、板等建筑构件，甚至更大的体积元素，如整个房间，都是在受控的环境中在异地制造的。和其他行业一样，自动化在建筑行业也越来越普遍。

Not only are highly automated equipment used in factories to manufacture building components faster and with a better quality control, works on site are also moving towards a greater degree of mechanization such as using machineries for interior fit-out in factory as shown in Fig. 12.Highly automated casting machine as depicted inFig. 13 increases the productivity and quality in manufacturing the building component. 

工厂不仅使用高度自动化的设备来更快地制造建筑部件，并进行更好的质量控制，现场的工作也在向更高程度的机械化迈进，如使用机器进行内部装修，如图12所示。高度自动化的铸造机，如图所示。提高建筑构件的生产效率和质量。

It is believed that 3D printing of a whole modular unit should be the future goal of modular construction. In addition, 3D laser scanner can be used to auto-scan the whole unit in factory and also after on-site installation to measure the verticality and horizontality of the modules,providing quick and accurate measurement.

三维打印整个模块化单元应该是未来模块化建设的目标。此外，3D激光扫描仪可以在工厂自动扫描整个单元，也可以在现场安装后测量模块的垂直度和水平度，提供快速和准确的测量。

In application to asset and inventory management, RFID system consists of a reader(scanner) and a tag with embedded chip and antenna. When tag appears in the reader’s working range (around 60 feet), it “wakes up”and sends a signal containing encoded information. The reader receives and decodes information, and sends it to the inventory and asset management software for processing.

在资产和库存管理的应用中，RFID系统由一个阅读器(扫描仪)和一个带有嵌入式芯片和天线的标签组成。当标签出现在阅读器的工作范围内(大约60英尺)，它“醒来”并发送一个包含编码信息的信号。读取器接收和解码信息，并将其发送到库存和资产管理软件进行处理。

RFID provides tremendous increase in processing speed as compared to traditional barcode scanning. Instead of scanning one item at a time, with RFID technology you can read information from all items in the working radius at the same time. For example, if you need to check in inventory on a service van, all you need to do is turn on RFID reader and information for all inventory in the van will be read and transmitted to an asset and inventory management software in a matter of seconds.

与传统的条形码扫描相比，RFID技术大大提高了处理速度。使用RFID技术，您可以同时读取工作半径内所有项目的信息，而不是一次扫描一个项目。例如，如果您需要检查服务货车上的库存，您所需要做的就是打开RFID阅读器，货车上的所有库存信息将在几秒钟内被读取并传输到资产和库存管理软件。

Furthermore, using BIM and other technologies, communication and decision making among architects, engineers, contractors, and building owners can be streamlined across all functional areas. The implementation augmented reality (AR) and virtual reality (VR)can further enhance the BIM models. With these technologies, project parties can experience a virtual walkthrough of a building even before it is constructed so that potential issues and problems can be identified and solved before actual construction. 

此外，使用BIM和其他技术，建筑师、工程师、承包商和建筑业主之间的沟通和决策可以在所有功能领域进行精简。增强现实(AR)和虚拟现实(VR)的实施可以进一步增强BIM模型。有了这些技术，项目各方甚至可以在建筑建造之前就体验到对建筑的虚拟演练，以便在实际建造之前识别和解决潜在的问题。

Advances in technology have also enabled BIM models to be accessed on site through cloud-connected mobile devices that all real-time sharing for efficient decision making. Lastly, with all the building information input in BIM models, the model can also be used to calculate the centre of gravity of each module,incorporating with auto-calibrated lifting frame,to stabilize the module during lifting in a quicker and easier way as well as minimizing the damage of the modules.

技术的进步也使得BIM模型可以通过云连接的移动设备在现场访问，所有的移动设备都是实时共享的，以实现高效决策。最后,所有的建筑信息输入BIM模型,该模型还可以用于计算每个模块的重心,将与auto-calibrated吊架,稳定模块在提升更快和更简单的方法以及减少模块的损坏。

Fig. 12. Interior fit-out in factory [15].

图12所示。工厂内部装修。

Fig. 13. Highly automated equipment is used in Singapore’s Integrated and Prefabrication Hubs to manufacture building components [14].

图13所示。高度自动化的设备用于新加坡的综合和预制制造中心，以制造建筑部件[14]。

4. Conclusion结论

Modular construction shows great potential in improving construction productivity and efficiency. Despite of the challenges in implementing this technology, several options are discussed as solution of these issues. It is believed that modular construction will shape the future construction industry.

模块化结构在提高建筑生产率和效率方面显示出巨大的潜力。尽管在实现该技术方面存在挑战，但作为这些问题的解决方案，我们讨论了几个选项。相信模块化建设将塑造未来的建筑行业。

Acknowledgement鸣谢

The authors would like to acknowledge the financial support by the National Research Foundation (NRF) and SembCorp-NUS Corp Lab under project grant R-261-513-009-281.

作者感谢国家研究基金会(NRF)和新加坡国立大学集团实验室在R-261-513-009-281项目资助下提供的资金支持。

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