楊天倫 喬治斯·卡普吉安尼斯 姜炳圭 羅賓·威爾遜

(1.寧波諾丁漢大學(xué)，寧波 315040； 2.英國諾丁漢大學(xué)，諾丁漢，英國 NG7 2RD)

引言 Introduction

In the design stage of a building project, poor coordination among different design disciplines is a common problem[1]. Poor design coordination will generate many issues, not only delay the design delivery, but also cause problems during the review and construction stage[2]. Repetitive modification (via contact forms) will occur during the construction process, causing unnecessary waste thus to delay the project delivery[3]. Building design is a complicated progress because the successful delivery heavily depends on efficient collaboration among each discipline[4]. Building design close-out only if the construction passes all inspection and deliver to user according to relevant domestic regulations[5]. The design management is important during design stage to ensure the successful coordination of each discipline and sharing of project information[6].

在土建工程的設(shè)計(jì)階段，各設(shè)計(jì)協(xié)調(diào)不充分的協(xié)調(diào)是一個常見的問題[1]。設(shè)計(jì)中協(xié)調(diào)不充分的協(xié)調(diào)會產(chǎn)生不良的結(jié)果，這不僅會延遲設(shè)計(jì)圖紙的交付，并且會導(dǎo)致項(xiàng)目在審查和施工階段出現(xiàn)問題[2]。設(shè)計(jì)交付質(zhì)量的不足會使設(shè)計(jì)單位在施工過程中多次出具聯(lián)系單對施工圖進(jìn)行修改，這將使設(shè)計(jì)團(tuán)隊(duì)產(chǎn)生不必要的資源浪費(fèi)并且可能導(dǎo)致項(xiàng)目的延遲竣工與交付[3]。土建工程設(shè)計(jì)是一項(xiàng)龐大并且復(fù)雜的過程，順利的設(shè)計(jì)交付在很大因素上取決于各設(shè)計(jì)專業(yè)良好的協(xié)同合作[4]。根據(jù)國內(nèi)的有關(guān)規(guī)定，土建設(shè)計(jì)要跟蹤服務(wù)到項(xiàng)目竣工并驗(yàn)收通過之后才算完成[5]。為確保各設(shè)計(jì)專業(yè)有良好的協(xié)同合作和更好的信息共享，設(shè)計(jì)管理在土建設(shè)計(jì)中有著重要的作用[6]。

Building Information Modelling (BIM) is becoming popular in Architecture Engineering and Construction (AEC) industry in recent years because it can increase the information coordination in architecture and infrastructure projects[7]. Design teams can improve their delivery performance in the case of all the building elements are well spatially optimized[8]. During the implementation of BIM, the models′ detail level play important role[9]. Domestic BIM standard raise the concept of "Level of Model Definition", and divide the model into four levels, which regulates the required information for each level[10]. American Institute of Architect (AIA) divides BIM model into five levels from 100 to 400[11]. These two standards both abbreviate the concept into LOD, which have similar function. LOD guides the implementation of BIM during different stages[12]. The implementation of BIM in design stage requires a clear information guidance to support the decision makings and assessments of design team regarding to the project[13]. Through the analysis and comparison of two standards, this paper consider AIA LOD 350 could effectively fill the gap between LOD 3.0 (components level) and LOD 4.0 (parts level) of the domestic standard in China. Therefore, this paper discusses and assess whether LOD 350 can effectively enhance design coordination, thus, to improve the design qualities in China.

建筑信息模型 (BIM) 近年來在建筑、工程和施工(AEC)企業(yè)中得到了廣泛的應(yīng)用，因?yàn)锽IM可以有效增加土建和基建項(xiàng)目中信息生產(chǎn)和管理的協(xié)同合作[7]。土建設(shè)計(jì)團(tuán)隊(duì)的設(shè)計(jì)交付能力將隨著各專業(yè)構(gòu)件在空間上的優(yōu)化而提高[8]。在BIM的執(zhí)行過程中，模型的精細(xì)程度起到了重要的作用[9]。國內(nèi)BIM標(biāo)準(zhǔn)《建筑信息模型設(shè)計(jì)交付標(biāo)準(zhǔn)》中提出了“模型精細(xì)度(Level of Model Definition)”的概念，并且將其劃分為四個等級，每個等級對模型所需涵蓋的基本單元做了規(guī)定[10]。美國建筑師協(xié)會(AIA)在BIM Forum中提出了“模型發(fā)展程度(Level of Development)”的概念，并對其從100到400進(jìn)行了五個等級的劃分[11]。這兩個標(biāo)準(zhǔn)中把這個概念均簡稱LOD，對模型精度的劃分有著異曲同工的作用。LOD為BIM在土建工程在不同階段的實(shí)施提供了相應(yīng)的模型參照標(biāo)準(zhǔn)[12]。在土建工程的設(shè)計(jì)階段，BIM執(zhí)行的關(guān)鍵是需要為設(shè)計(jì)團(tuán)隊(duì)提供相應(yīng)級別的模型細(xì)節(jié)來對項(xiàng)目的設(shè)計(jì)進(jìn)行決策與評估[13]。經(jīng)過對兩個模型精度標(biāo)準(zhǔn)的對比分析與研究，本文認(rèn)為AIA標(biāo)準(zhǔn)的LOD 350能有效填補(bǔ)國內(nèi)標(biāo)準(zhǔn)中LOD 3.0 (構(gòu)件級) 與LOD 4.0(零件級)模型單元之間的空白，所以，本文對LOD 350在國內(nèi)設(shè)計(jì)單位中的應(yīng)用是否能提高各設(shè)計(jì)專業(yè)之間的信息協(xié)調(diào)能力與是否能提高設(shè)計(jì)交付的質(zhì)量進(jìn)行了討論和分析。

1 研究目標(biāo)、對象和方法 Research Aim, Objects and Methodologies

The aim of this research is to understand whether and how LOD 350 can improve design coordination and thus to improve the design quality. The research objectives of this paper are a) identify the problems and issues in building design management during construction drawing phase b) define properties and characteristic of LOD 350 and c) understand the interrelationships between LOD 350 and design coordination within Chinese Industry.

本文的研究目標(biāo)為明確LOD 350是否能通過提高施工圖設(shè)計(jì)各專業(yè)之間的協(xié)調(diào)來提高設(shè)計(jì)交付的質(zhì)量，并且認(rèn)識這個過程是如何實(shí)現(xiàn)的。本文的研究對象為: a) 確定在施工圖設(shè)計(jì)階段的管理中有哪些不良的因素; b) 定義LOD 350的屬性和特征; c) 理解在國內(nèi)設(shè)計(jì)單位中，LOD 350與設(shè)計(jì)協(xié)調(diào)之間的關(guān)聯(lián)。

Researchers are using mixed method approach aiming to get a more objective approach of people′s opinion. Methodologically researchers follow a case study approach and using mixed method (observation and semi structured interviews). Researchers worked on a small residential project that is based in Ningbo, China. Interview participants are from a design company which has Class A building design license and a construction supervision company which has Class A building construction supervision license. Researchers analysed the relation between different disciplines in construction documents design phase. Ethics clearance was provided by the University of Nottingham Ningbo China before the research starts.

圖1 研究方法Fig.1 Research Methodology

本研究采用混合方法來更加客觀地從被采訪人員的觀點(diǎn)中獲得研究數(shù)據(jù)，同時，研究通過混合方法來對一個案例進(jìn)行研究(觀測和半結(jié)構(gòu)式的訪談)。本研究的案例是一個位于浙江省寧波市的小型住宅項(xiàng)目；本研究通過采訪一所建筑工程甲級資質(zhì)設(shè)計(jì)單位的設(shè)計(jì)人員和一所房屋建筑工程甲級資質(zhì)監(jiān)理單位的監(jiān)理人員來分析不同專業(yè)在施工圖設(shè)計(jì)階段的關(guān)聯(lián)。寧波諾丁漢大學(xué)在研究開始前通過了對此次研究倫理道德的審查。

For the first research objective, the researchers use literature review to investigate those existing issues in building design, to find those factors that cause poor design management. Moreover, for the second research objective, researchers use semi structured interviews and case scenario to understand certain challenges during the design documents coordination following by observations from the experiment. Findings compared to comprehensive literature review in LOD based on up-to-date standards, analysed the impact of LOD 350 in construction drawing design phase. Finally, the third objective aims to understand the impact of LOD 350 in a scenario and presenting its findings in terms of "how LOD 350 could help to improve document coordination during the design stage of a project".

針對第一個研究對象，研究人員采取文獻(xiàn)綜述對現(xiàn)階段的設(shè)計(jì)問題進(jìn)行了全面的調(diào)查，找出導(dǎo)致不良設(shè)計(jì)管理的因素。此外，針對第二個研究對象，研究人員采用半結(jié)構(gòu)式訪談和場景案例來理解設(shè)計(jì)文件協(xié)調(diào)中的難點(diǎn)，隨后對實(shí)驗(yàn)進(jìn)行了觀測。本文將研究結(jié)果與基于業(yè)內(nèi)最新標(biāo)準(zhǔn)和規(guī)范的LOD 350特征進(jìn)行對比，分析了LOD 350在施工圖設(shè)計(jì)階段的作用。最后，第三個研究對象為理解LOD 350在一個場景中的作用，并且通過“在項(xiàng)目設(shè)計(jì)階段LOD 350將如何幫助提高設(shè)計(jì)文件的協(xié)調(diào)”的方式來展示研究的結(jié)果。

2 施工圖文件在設(shè)計(jì)管理中的問題 Issues of Construction Documents in Design Management

The quality of design documents delivery is important in building project because poor design coordination will delay the construction progress[14]. The traditional building design tools and methods effects the efficiency of this discipline, compare with the history along the century of building design, the current of design delivery is still based on two dimensional sheets[2]. Two dimensional sheets have limitations in spatial coordination, which will affect the evaluation of design team regarding to the potential design problems[15]. Despite the widely adoption of many three-dimensional design tools such as SketchUp and Revit, they are merely adopted in initial design phase, however not deep into construction documents design phase[16]. Many domestic design companies are lack of widely adopt those useful three-dimensional tools to integrate all design disciplines to improve design efficiencies and qualities[17]. Building projects require coordination from multiple disciplines across different stages[18]. These stages consist geological survey, design, and construction (Figure 2). According to domestic regulations, design companies shall respond to relevant questions from construction company during construction stage (via contract forms). Therefore, poor design quality will cause design team to spend extra time making design modifications during construction process. However, ISO 19650 was introduced as a standard to optimise information modelling process in construction projects[19]. In China, this standard is getting attention but not been widely adopted.

設(shè)計(jì)文件交付的質(zhì)量是整個建設(shè)工程的關(guān)鍵，因?yàn)槲闯浞謪f(xié)調(diào)的設(shè)計(jì)文件會影響施工的進(jìn)程[14]。土建設(shè)計(jì)工具與方法的傳統(tǒng)性極大限制了這個行業(yè)的效率，對比建筑設(shè)計(jì)行業(yè)幾個世紀(jì)以來的歷史，現(xiàn)階段土建項(xiàng)目對于設(shè)計(jì)的交付仍然停留在二維的圖紙上[2]。二維的設(shè)計(jì)圖紙?jiān)诳臻g優(yōu)化與協(xié)調(diào)上具有相當(dāng)程度的局限性，這將影響了設(shè)計(jì)團(tuán)隊(duì)對潛在的設(shè)計(jì)問題進(jìn)行評估[15]。盡管近年來許多三維設(shè)計(jì)軟件比如SketchUp與Revit在設(shè)計(jì)單位得到了廣泛應(yīng)用，但是這些使用僅僅停留在初步階段，并沒有對施工圖設(shè)計(jì)階段進(jìn)行深入的優(yōu)化[16]。國內(nèi)的許多設(shè)計(jì)單位缺乏廣泛采用對各設(shè)計(jì)專業(yè)具備有效信息協(xié)調(diào)作用的三維工具來提高土建設(shè)計(jì)的效率與質(zhì)量[17]。土建項(xiàng)目在每個階段均需要各個專業(yè)的配合[18]。這些階段重點(diǎn)包括勘查、設(shè)計(jì)與施工(圖2)。根據(jù)國內(nèi)的相關(guān)法規(guī)，在項(xiàng)目施工的過程中設(shè)計(jì)單位需要對施工單位所提出的相關(guān)問題進(jìn)行書面答復(fù)(出具聯(lián)系單)。所以，設(shè)計(jì)交付質(zhì)量的不足將會導(dǎo)致設(shè)計(jì)單位在施工階段耗費(fèi)大量的精力對設(shè)計(jì)進(jìn)行調(diào)整。ISO 19650的提出為建設(shè)工程信息建模的過程提供了一個標(biāo)準(zhǔn)[19]。在中國，這個標(biāo)準(zhǔn)已經(jīng)得到重視但未進(jìn)行廣泛采用。

圖2 項(xiàng)目交付流程Fig.2 Project Delivery Process

Construction documents design provides details to constructions stage[20]. Construction drawings design demand the collaboration of multiple disciplines, including but not restrict to architecture, structure, and MEP/HVAC (Figure 3). During the construction documents design, lack of communication among different disciplines is a common problem[21]. Because the frequency of design modification, if the modified information cannot be delivered to relevant discipline timely, it will cause the information delay and modification delay, thus lead to the poor coordination in the end[22]. The limitation of communication tools among design team is another problem that cause poor communication during the design process[23]Following the lack of collaborative culture, the performance of construction project will be affected thus likely will end up with failure[24]. In domestic design companies, it lacks to widely adopt Common Data Environment (CDE) platforms; those common instant communication tools are not able to effectively provide storage and share documents (regarding to the historic version of design documents and are not able to provide effectively feedback - design review and references)[25]. In domestic building design companies, architecture is the leading discipline to coordinate and review the designs. Meanwhile, as being considered as core disciplines, the coordination between architecture and structure is important to ensure the spatial reasonability[26]. The MEP disciplines provide building equipment design based on architecture and structural design. These designs are integrated in order using relevant tools[8](e.g. Navisworks clashes must be reported).

施工圖設(shè)計(jì)的主要目的是為施工階段提供了相應(yīng)的構(gòu)造與細(xì)節(jié)做法[20]。施工圖設(shè)計(jì)需要多專業(yè)的協(xié)同合作，這些專業(yè)包括但不局限于建筑、結(jié)構(gòu)和機(jī)電(圖3)。在施工圖的設(shè)計(jì)中，各專業(yè)缺乏在設(shè)計(jì)內(nèi)容與信息上的有效交流是一個常見的問題[21]。由于在設(shè)計(jì)過程中設(shè)計(jì)變更的頻繁，變更信息如果無法及時傳遞給相關(guān)專業(yè)，將會產(chǎn)生信息的滯后和設(shè)計(jì)修改的不及時，最后導(dǎo)致在各專業(yè)設(shè)計(jì)圖紙匯總后發(fā)現(xiàn)在空間上的不協(xié)調(diào)[22]。各設(shè)計(jì)專業(yè)之間交流工具的局限性也是導(dǎo)致在設(shè)計(jì)過程中缺乏有效交流的原因之一[23]。在一個缺乏協(xié)同合作的環(huán)境下，建設(shè)項(xiàng)目的績效會受到影響，并且有可能會導(dǎo)致一個失敗的結(jié)局[24]。在國內(nèi)的設(shè)計(jì)單位中，缺乏廣泛采用公共數(shù)據(jù)環(huán)境(CDE)平臺；常用的即時通訊工具不能有效地對歷史版本的設(shè)計(jì)文件進(jìn)行儲存與共享，并且不能使設(shè)計(jì)團(tuán)隊(duì)對設(shè)計(jì)文件進(jìn)行有效的反饋(設(shè)計(jì)審查和參考)[25]。在國內(nèi)的設(shè)計(jì)單位中，建筑專業(yè)通常作為設(shè)計(jì)總負(fù)責(zé)來對各專業(yè)的圖紙進(jìn)行匯總并審閱。同時，作為項(xiàng)目設(shè)計(jì)的主要專業(yè)，建筑和結(jié)構(gòu)設(shè)計(jì)之間需要進(jìn)行充分的協(xié)調(diào)，以確保項(xiàng)目在空間上的合理性[26]。機(jī)電專業(yè)基于建筑與結(jié)構(gòu)的設(shè)計(jì)為項(xiàng)目提供設(shè)備的設(shè)計(jì)。這些專業(yè)之間需要通過一些工具來進(jìn)行整合[8](比如通過Navisworks來進(jìn)行碰撞檢測)。

圖3 專業(yè)之間的協(xié)調(diào)Fig.3 Coordination Between Disciplines

During the construction drawing design phase, each discipline needs to make changes should comply with schematic design and relevant standards[27]. The lack of pre-identifying potential construction problems during the construction design phase is one of the reasons that cause the delay of the building project[28]. Design team does not make design based on the real construction process and does not make spatial simulations. This result to design inadequacies[29]. The design team uses inefficient communication methods and irrelevant reference information can seriously affect the design efficiencies[30]. The delivery of design can be considered as information delivery (Figure 4). It requires the use of effective reference standard system, mutually agreed, during information production to ensure the information quality and validity[3]. As a result the information production and its quality depends heavily also on the efficiency of information coordination, and in particular to be reviewed by the right person[4]. On this basis researchers run semi structured interviews to seek those challenges (architecture and structure disciplines) based on documents coordination. The output of this research is to meet requirements of the second objective.

在施工圖設(shè)計(jì)階段，各專業(yè)需要依據(jù)所定方案和相關(guān)規(guī)范來開展設(shè)計(jì)[27]。施工圖設(shè)計(jì)未考慮實(shí)際建造中的問題是導(dǎo)致項(xiàng)目延遲交付的原因之一[28]。設(shè)計(jì)人員未從實(shí)際角度出發(fā)，缺乏對建筑構(gòu)件在空間上的模擬與協(xié)調(diào)將會降低設(shè)計(jì)的質(zhì)量[29]。同時各專業(yè)設(shè)計(jì)人員在設(shè)計(jì)過程中采用低效的溝通方法和使用不充分參考信息會降低設(shè)計(jì)的效率[30]。工程設(shè)計(jì)的交付可以被認(rèn)為是一種信息的交付(圖4)。在信息的生產(chǎn)中需要采取相互認(rèn)可的，并且有效的參考標(biāo)準(zhǔn)來確保信息的質(zhì)量與正確性[3]。作為結(jié)果，研究信息的生產(chǎn)和其質(zhì)量同樣極大程度上依賴信息協(xié)調(diào)的效率，并且尤其需要通過合適的人來進(jìn)行審閱[4]?；谶@個理論，作為案例研究的一部分，本研究采取了半結(jié)構(gòu)式的訪談來從設(shè)計(jì)團(tuán)隊(duì)(建筑和結(jié)構(gòu)專業(yè))中尋找施工圖設(shè)計(jì)文件協(xié)調(diào)的難點(diǎn)。訪談的研究結(jié)果是針對第二個研究對象所需要的要求。

圖4 信息協(xié)調(diào)過程Fig.4 Process of Information Coordination

For the interview in architecture discipline, the research focuses on how it should provide useful information to other disciplines, and how to coordinate with other disciplines through effective communication. For the interviews on structure discipline, this research focuses on how structure discipline needs to coordinate with architecture discipline to achieve design objectives. For the interview on construction supervision discipline, the research focuses on which types of issues in construction documents will impact to the construction progress, and to investigate how design team and construction supervision teams need to coordinate in order to improve the delivery efficiency. Researchers used Nvivo Software to analyse qualitative data by using content analysis method[31]. Based on content analysis, through coding of nodes in Nvivo, researchers tried to map the relationships between the nodes. The key nodes among others are: communication, cooperation, design, construction, information, management, space, etc. Through cluster analysis, Nvivo generated the following diagram (Figure 5) by showing the core challenges in documents coordination in design and construction phase.

在針對建筑專業(yè)的研究中，訪談著重調(diào)查在設(shè)計(jì)的過程中，建筑專業(yè)應(yīng)該如何向其它專業(yè)提供有效信息并且應(yīng)該如何與其它專業(yè)進(jìn)行高效的溝通與協(xié)調(diào)。在針對結(jié)構(gòu)專業(yè)的研究中，訪談著重調(diào)查結(jié)構(gòu)專業(yè)應(yīng)該如何與建筑專業(yè)進(jìn)行有效配合來實(shí)現(xiàn)與完成設(shè)計(jì)任務(wù)。在針對監(jiān)理專業(yè)的調(diào)查中，訪談專注于哪些施工圖上的問題會影響施工的過程，并且著重于調(diào)查建筑和監(jiān)理專業(yè)應(yīng)該如何協(xié)調(diào)來提高項(xiàng)目交付的效率。研究人員采用Nvivo軟件通過內(nèi)容分析的方法對所收集的定性數(shù)據(jù)進(jìn)行分析[31]?；趦?nèi)容分析，通過在Nvivo里對關(guān)鍵節(jié)點(diǎn)的編碼，研究人員嘗試對節(jié)點(diǎn)建立關(guān)聯(lián)圖。關(guān)鍵節(jié)點(diǎn)包括：溝通、協(xié)作、設(shè)計(jì)、施工、信息、管理、空間等。Nvivo根據(jù)聚類分析，生成如圖5所示來展示設(shè)計(jì)和施工階段在設(shè)計(jì)文件協(xié)調(diào)上的難點(diǎn)。

圖5 Nvivo分析結(jié)果Fig.5 Nvivo Analysis Result

According to data analysis results, design will correlate with construction through communication based on the semi structured interviews with construction supervision team. In addition, findings show as a common problem that sheets from different disciplines do not match or compliment with each other. The data in (Figure 5) shows design and construction documents need to be linked through coordination. In addition, findings shown that the feedback comes to building design rather than points out those construction difficulties. Furthermore, findings shown belated design modification is one of the factors that impact construction. In addition, the Figure 5 shows the coordination of information is related to the precision of information. Also, findings shown from structure discipline lack of clear data in size and shape could cause clashes during the data/information integration as well as challenges with spatial coordination. Therefore, there is a need to model more details to get more a better understanding of potential clashes. These must be discussed with other disciplines to ensure information consistency and high level of quality (note: information is produced in LOD 350 aim to be better enhanced by LOD 400 that will be ready for construction purposes). With the implementation of BIM, design team can visualize more problems[32]. As a result, LOD 350, as an addition element to LOD 300 or LOD 3.0 standard to optimize construction documents design (Figure 6). Also, LOD 350 could be advantageous to be incorporated to secure optimised project communication.

Nvivo根據(jù)對監(jiān)理專業(yè)的半結(jié)構(gòu)式訪談數(shù)據(jù)分析結(jié)果顯示，設(shè)計(jì)(Design)通過溝通(Communication)的方式與施工(Construction)建立關(guān)聯(lián)。另外，數(shù)據(jù)表明，現(xiàn)階段各專業(yè)的設(shè)計(jì)圖紙?jiān)趨R總后會產(chǎn)生不一致或相互不能匹配是一個常見的問題。根據(jù)圖5的數(shù)據(jù)表明，設(shè)計(jì)(Design)和施工(Construction)與協(xié)調(diào)(Coordination)具有關(guān)聯(lián)性。同時數(shù)據(jù)表明，許多反饋僅針對設(shè)計(jì)的問題而非指出在施工上的難點(diǎn)。此外，研究結(jié)果表明，不及時的設(shè)計(jì)變更也是影響施工的因素之一。而且，圖5的數(shù)據(jù)表明，信息的協(xié)同合作(Coordination)和信息的精度(Precision)相關(guān)聯(lián)。根據(jù)對結(jié)構(gòu)專業(yè)的訪談數(shù)據(jù)中發(fā)現(xiàn)，各構(gòu)件位置與尺寸信息缺失的將會導(dǎo)致在設(shè)計(jì)整合中發(fā)生空間上的碰撞。所以，需要通過建立更加詳細(xì)的BIM模型來獲得對項(xiàng)目設(shè)計(jì)在空間上潛在的碰撞進(jìn)行更加透徹的了解。這需要通過與其它專業(yè)的討論與溝通來確保信息的一致性和信息的高質(zhì)量(注意，在LOD 350階段所生產(chǎn)的信息是為了能在LOD 400階段被更好地優(yōu)化，來為施工過程提供信息參考)。BIM的應(yīng)用可以使設(shè)計(jì)團(tuán)隊(duì)更好地對項(xiàng)目進(jìn)行可視化，通過檢測和分析發(fā)現(xiàn)空間設(shè)計(jì)上的問題[32]。研究結(jié)果顯示，LOD 350作為LOD 300或者LOD 3.0 標(biāo)準(zhǔn)的附加元素，可以為施工圖設(shè)計(jì)文件做出優(yōu)化調(diào)整(圖6)。同時，LOD 350可以為項(xiàng)目優(yōu)化的交流做出有效保障。

圖6 LOD 350在設(shè)計(jì)階段Fig.6 LOD 350 in Design Stage

Considering therefore findings from the literature review and research outputs, it is evident the need to utilise LOD 350 in the design stage of construction drawings development to eliminate communication risks. However, this requires appropriate information reference system; the use of ISO 19650 could be sufficiently enough to elaborate this challenge[19]. As a result, efficient document coordination through clash detection in early stage could support the development of LOD 400 accordingly. The adoption of this level needs to base on LOD 300 because LOD is a progress development[11]. Next section will analyse the difference between LOD 300 and LOD 350, evaluated the role of each level in design stage.

綜合考慮文獻(xiàn)綜述和半結(jié)構(gòu)式訪談的研究結(jié)果，LOD 350被證實(shí)在施工圖設(shè)計(jì)階段能夠有效降低設(shè)計(jì)團(tuán)隊(duì)在交流上存在差錯的風(fēng)險。但是，這個需要擁有合適的信息參考系統(tǒng)，采取ISO 19650能夠有效應(yīng)對來自這方面的挑戰(zhàn)[19]。所以，在設(shè)計(jì)階段通過沖突檢測的方式對設(shè)計(jì)文件進(jìn)行及時協(xié)調(diào)能夠有效支持LOD 400階段BIM模型的建立。采取這個級別的BIM模型需要基于LOD 300的基礎(chǔ)上，因?yàn)長OD的建立是一個累加的過程[11]。下一章節(jié)分析了LOD 300和LOD 350的區(qū)別，并且評估了兩者在土建設(shè)計(jì)階段的作用。

3 LOD 350 精度的特征研究 Features of LOD 350

圖7 空間協(xié)調(diào)不足Fig.7 Insufficient Spatial Coordination

圖8 LOD 350投入和產(chǎn)出Fig.8 Input and Output of LOD 350

Level of Development (LOD) 350 based on AIA standard is introduced on BIM Forum in 2013[33]. LOD 350 is defined between LOD 300 and LOD 400, which models the actual shape and size of building components and make the connection joints in between, aims to improve design optimization before making construction model[11]. Different phases in design stage demand different information level to support decision making and evaluation process[34]. has regulated the delivery accuracy[10]. But this standard was released in December of 2018 and implemented in June of 2019, so before that, the implementation of BIM is normally reference on AIA LOD standard. In domestic construction documents design phase, LOD 300 (equal to domestic standard LOD 3.0 parts level) are mostly being adopted during the BIM implementation. Due to the limitation of LOD 300, spatial coordination at this level might not be enough, therefore, it still will cause multiple problems during construction process (Figure 7).

美國建筑師協(xié)會(AIA)標(biāo)準(zhǔn)的LOD 350 首次于2013年在BIM Forum 上提出[33]。LOD 350被定義在LOD 300 與LOD 400之間，其要求是對項(xiàng)目各構(gòu)件進(jìn)行真實(shí)外型與尺寸的建模，并且在各構(gòu)件之間要求建立連接件，這對建立BIM施工模型前的優(yōu)化起到了過渡的作用[11]。在項(xiàng)目設(shè)計(jì)的不同階段需要不同級別的信息細(xì)節(jié)來為設(shè)計(jì)評估與決策的過程提供參考信息[34]。《建筑信息模型設(shè)計(jì)交付標(biāo)準(zhǔn)》中對BIM模型精度的交付標(biāo)準(zhǔn)做出了規(guī)定[10]。這個標(biāo)準(zhǔn)于2018年12月推出，并且于2019年6月正式實(shí)施，在此之前，BIM執(zhí)行計(jì)劃通常參考AIA的LOD標(biāo)準(zhǔn)。 在國內(nèi)施工圖設(shè)計(jì)階段的BIM應(yīng)用中，最常用的是LOD 300級別，等同于現(xiàn)行國內(nèi)標(biāo)準(zhǔn)的LOD 3.0(構(gòu)件級)。由于LOD 300 在建模深度上的局限性，這個級別的BIM模型并不能發(fā)現(xiàn)許多空間協(xié)調(diào)上潛在的不足，所以導(dǎo)致在施工的過程中仍然會出現(xiàn)許多構(gòu)件碰撞的問題(圖7)。

During BIM implementation, build models at AIA LOD 400 or domestic standard LOD 4.0 (parts level) require input with large amount of workload because this level contains construction details[11]. If design stage is not well coordinated, efforts will be spent to make modifications in LOD 400 or LOD 4.0, which will cause unnecessary resource waste. So, the principle of BIM paradigm can be considered and thus no lean management is applied[35]. Despite develop LOD 350 require inputting certain resource, it will improve design optimization based on LOD 300, which can reduce modification in later stage (Figure 8).

在BIM的執(zhí)行過程中，建立AIA標(biāo)準(zhǔn)LOD 400或者國內(nèi)標(biāo)準(zhǔn)LOD 4.0(零件級)的BIM模型需要投入大量的資源與精力，因?yàn)檫@個級別的BIM模型包含了全面并且詳細(xì)的施工細(xì)節(jié)[11]。如果在設(shè)計(jì)階段未能充分將各設(shè)計(jì)專業(yè)的圖紙進(jìn)行協(xié)調(diào)，在依據(jù)LOD 400或者LOD 4.0建立BIM模型的過程中，會在修改與調(diào)整上消耗更多的精力，這將會產(chǎn)生許多不必要的資源浪費(fèi)。這被認(rèn)為是一種BIM的典范，所以不需要投入額外的精細(xì)化管理[35]。盡管采用LOD 350的標(biāo)準(zhǔn)需要投入一定量的資源，但是LOD 350能針對LOD 300對設(shè)計(jì)做出空間協(xié)調(diào)的優(yōu)化，減少后期在修改上所消耗的精力(圖8)。

The clash between building components happens frequently during construction stage because of the insufficient detail level of design documents[3]. Therefore, an efficient solution is demanded to improve design quality during construction documents design phase. (Figure 9) illustrated the relation between different components and highlighted their potential clash. BIM models in LOD 350 require presenting actual size and shape, also it requires to develop connection joints[11]. Therefore, it would be advantageous to enhance spatial optimization at in during the modelling process by providing higher and accurate level of details.

圖9 各構(gòu)件潛在碰撞Fig.9 Potential clash between components

由于設(shè)計(jì)交付圖紙深度的不足，各構(gòu)件在施工中容易頻繁發(fā)生碰撞[3]。所以，在施工圖設(shè)計(jì)階段，需要一種有效的參考信息來提高設(shè)計(jì)在空間協(xié)調(diào)上的質(zhì)量。圖9列舉了不同構(gòu)件之間的關(guān)聯(lián)，著重表示了一些容易發(fā)生碰撞的部位。LOD 350要求模型各構(gòu)件建立真實(shí)的尺寸和外形，并且要求建立目標(biāo)構(gòu)件與周邊相鄰構(gòu)件的連接部件[11]。所以BIM模型在這個級別中可以為設(shè)計(jì)團(tuán)隊(duì)提供更多有效的參考細(xì)節(jié)，來對空間協(xié)調(diào)進(jìn)行進(jìn)一步的優(yōu)化。

The major different between LOD 300 and LOD 350 is the fact that objects can be linked and interconnected[11]. In (Figure 10) is illustrated the detail requirement of each component in different LOD in more detail. Components from different disciplines have different requirements, LOD 350 requires MEP (Mechanical, Electrical and Plumbing) and HVAC (Heating, Ventilation and Air Conditioning). As a result that requires to build actual spatial coordination[11]. Spatial coordination can be efficiently optimized based on this level of BIM model. Therefore, compare to LOD 300, this research consider BIM models at LOD 350 level can show advantages in spatial coordination and thus improve the design requirements.

LOD 350與LOD 300的關(guān)鍵不同之處為，LOD 350要求建立目標(biāo)構(gòu)件與周圍構(gòu)件的連接件[11]。圖10列舉了各構(gòu)件在不同LOD中的要求。不同專業(yè)的構(gòu)件在細(xì)節(jié)上有著不同的要求，LOD 350規(guī)定機(jī)電和暖通專業(yè)的BIM模型構(gòu)件須建立與現(xiàn)實(shí)相一致的凈高和空隙[11]。根據(jù)這個級別的BIM模型，空間協(xié)調(diào)能被設(shè)計(jì)團(tuán)隊(duì)進(jìn)行有效分析并且優(yōu)化。所以本研究認(rèn)為LOD 350相比LOD 300可以在施工圖設(shè)計(jì)的空間優(yōu)化中發(fā)揮極大的優(yōu)勢來提高空間協(xié)調(diào)的質(zhì)量，以此提高設(shè)計(jì)團(tuán)隊(duì)的業(yè)務(wù)能力。

圖10 LOD 350在不同建筑部件中的精度要求Fig.10 LOD 350 Specification in Different Building Components

According to the features of LOD 350, this level of BIM model will help design team to improve review and constructability through visualization (using tools such as HoloLens, HTC Vive etc) and simulation through gamification. The next section uses the scenario on the use of LOD 350 in Ningbo, China. Researchers tried to identify the impact of LOD 350 in construction documents design and assess the effectiveness of it to improve design quality.

根據(jù)LOD 350的特性，這個級別的BIM模型能通過可視化(采用HoloLens和HTC Vive之類的硬件工具)和游戲化的模擬來幫助設(shè)計(jì)團(tuán)隊(duì)提高對項(xiàng)目審閱的能力，同時能提高項(xiàng)目的可施工性。下一章節(jié)將通過一個位于浙江寧波，并且采用了LOD 350的場景案例，來分析來討論LOD 350在施工圖設(shè)計(jì)中的作用。本研究著重于確定LOD 350的作用，以此評估LOD 350對提高設(shè)計(jì)整體質(zhì)量的有效性。

4 用例場景 Use Case Scenario

Considering the case study methodologically approach, researchers used a use case scenario to validate the process, in fact a kitchen of a small residential project. The project data provided under ethical approval by Zhejiang Jingwei Engineering Design Co., Ltd to be used by the University of Nottingham Ningbo China for the shake of this projects. In a more detail the kitchen includes multiple disciplines. Each discipline contains multiple system and components, for example, water supply, hot water, sewage, ventilation, lighting etc. This project implements BIM through the entire process, using LOD 350 (filling the gap between LOD 3.0 and LOD 4.0 in China) to model each component, integrated and checked each system in the master model, which achieved good design results.

圖11 LOD 350優(yōu)化的模型 Fig.11 Optimized Model at LOD 350

圖12 土建各構(gòu)件之間的聯(lián)系 Fig.12 Interaction Between Building Components

考慮到案例研究中的方法論，研究人員采取用例場景通過一棟小型住宅的廚房設(shè)計(jì)來對過程進(jìn)行證實(shí)。項(xiàng)目數(shù)據(jù)由浙江經(jīng)緯工程設(shè)計(jì)有限公司提供。廚房的設(shè)計(jì)包含了多個專業(yè)，在每個專業(yè)中包含許多系統(tǒng)和構(gòu)件，例如：供水系統(tǒng)，熱水系統(tǒng)，污水系統(tǒng)，排煙系統(tǒng)，以及照明系統(tǒng)等。本項(xiàng)目在設(shè)計(jì)的過程中全程應(yīng)用了BIM技術(shù)，通過LOD 350標(biāo)準(zhǔn)(為填補(bǔ)國內(nèi)LOD 3.0和LOD 4.0標(biāo)準(zhǔn)之間的空白)對項(xiàng)目各構(gòu)件進(jìn)行了建模，并對各系統(tǒng)在主BIM模型中進(jìn)行整合與優(yōu)化，最終取得了良好的設(shè)計(jì)效果。

The project lists all building components in kitchen during the BIM implementation, classified these components based on their discipline and analysed their relation (Figure 12). Before develop model into LOD 350, this project assesses and evaluated the demand; based on the relation of components in different system, this project evaluated the impact of these components to design coordination in LOD 350. Meanwhile, this project reviewed BIM models at LOD 200 and LOD 300 to explore those issues need to be addressed in LOD 350. The results are,

(1)Spatial relation between lintel and structural beam;

(2)Spatial coordination between plumbing components and mechanical equipment;

(3)Spatial coordination between appliance and room space.

Based on these analyses, this project developed BIM model based on LOD 300, enhance those important components to LOD 350 to coordinate space and optimize design.

本案例在BIM的執(zhí)行過程中，首先對廚房內(nèi)的所有構(gòu)件進(jìn)行了詳細(xì)的統(tǒng)計(jì)，對這些構(gòu)件根據(jù)所屬專業(yè)進(jìn)行分類，并且分析了各構(gòu)件之間的關(guān)聯(lián)(圖12)。本項(xiàng)目在建立LOD 350級別的BIM模型之前，對項(xiàng)目的需求和目標(biāo)進(jìn)行了調(diào)查和評估，通過對組成各系統(tǒng)的構(gòu)件之間的聯(lián)系來評估這些項(xiàng)目構(gòu)件在LOD 350級別時如何作用廚房整體的設(shè)計(jì)協(xié)調(diào)與優(yōu)化。同時，通過審閱LOD 200的方案設(shè)計(jì)模型與LOD 300的施工圖設(shè)計(jì)模型來總結(jié)需要LOD 350所解決的問題。分析結(jié)果如下：

(1)門窗過梁與結(jié)構(gòu)梁之間的空間關(guān)系；

(2)水管構(gòu)件與相應(yīng)機(jī)電設(shè)備之間的空間協(xié)調(diào)；

(3)廚房電器與整體使用空間之間的協(xié)調(diào)。

根據(jù)前期分析，項(xiàng)目對LOD 300級別的BIM模型進(jìn)行深化，對重點(diǎn)部位建立LOD 350級別的BIM模型來對空間協(xié)調(diào)進(jìn)行檢測和優(yōu)化。

Based on different disciplines, this project developed each important component to LOD 350 in Revit, and then linked these components into master model. During the integration, it detects those highlighted area exists clashes, through carefully review, these clashes are mainly including,

(1)Structural beam with Window;

(2)MEP system with Structural beam;

(3)MEP components in architectural space;

(4)Appliance in architectural space.

Through enhancing important area based on LOD 300, this project detects spatial clashes and made efficient modification. The requirement of LOD 350 to each component is to match with real objects, which are helpful to find potential problems through BIM models, especially during MEP enhancement design. This project adopt LOD 350 during BIM implementation, enables design team to make efficient spatial coordination and optimization, which improved the design quality. That aligns to digital assets of buildings, but this is beside the scope of this research.

根據(jù)不同專業(yè)，本項(xiàng)目采用Revit軟件對重點(diǎn)部位進(jìn)行了LOD 350級別的建模，通過鏈接的方式在主BIM模型中進(jìn)行整合。在整合模型的過程中，通過檢測，發(fā)現(xiàn)這些重點(diǎn)部位在許多構(gòu)件在空間上存在相互沖突的情況，經(jīng)過仔細(xì)分析，這些沖突主要包含：

(1)結(jié)構(gòu)梁與窗戶之間的沖突；

(2)給排水系統(tǒng)與結(jié)構(gòu)梁之間的沖突；

(3)給排水構(gòu)件在建筑使用空間上的沖突；

(4)電氣設(shè)備在建筑使用空間上的沖突。

通過對LOD 300級別的BIM模型進(jìn)行重點(diǎn)部位的深化，各構(gòu)件在空間上的沖突通過可視化的模擬得到了及時的發(fā)現(xiàn)并進(jìn)行調(diào)整。LOD 350對各構(gòu)件的精度要求是達(dá)到與現(xiàn)實(shí)相一致，這非常有利于通過BIM模型來發(fā)現(xiàn)空間上潛在的問題，尤其是在機(jī)電專業(yè)的深化設(shè)計(jì)上。此項(xiàng)目采取LOD 350級別的BIM模型，設(shè)計(jì)團(tuán)體對建筑整體的空間協(xié)調(diào)做出了及時的優(yōu)化，提高了施工圖設(shè)計(jì)的質(zhì)量。這同時匹配建筑數(shù)字資產(chǎn)所需的要求，但是數(shù)字資產(chǎn)不在本研究的范圍之內(nèi)。

LOD 350 requires building components have accordance with real object and have connection joints to simulate real space situation. The biggest contribution of LOD 350 to this project is the coordination with the MEP, architecture, and structure components. The spatial clash of MEP components is one of the largest problems during the design stage. Therefore, extra human workload is required to improve design and operational quality of the asset. Through this scenario, this research analysed and assessed the successful process, which comes with the conclusion: LOD 350 can realistically be implemented during BIM modelling process aiming to improve design, building′s functions and arrange an improved spatial design specification.

LOD 350 級別要求BIM模型的構(gòu)件在外型尺寸上與現(xiàn)實(shí)保持相一致，同時要求建立起各構(gòu)件與周圍構(gòu)件的連接件來確保在空間上的真實(shí)模擬。本項(xiàng)目中LOD 350對項(xiàng)目設(shè)計(jì)最大的貢獻(xiàn)在于對MEP、建筑和結(jié)構(gòu)在空間上的協(xié)調(diào)，而MEP在空間上與其它專業(yè)的沖突往往是影響設(shè)計(jì)質(zhì)量的最大因素之一。所以，額外的人力需要被投入，以此來改善資產(chǎn)設(shè)計(jì)和運(yùn)維的質(zhì)量。通過這個場景案例，本研究分析和評估了項(xiàng)目成功的過程，得出的結(jié)論為：LOD 350可以被實(shí)際地應(yīng)用到BIM建模的過程中，為此來提高設(shè)計(jì)的質(zhì)量、項(xiàng)目的功能和空間上的協(xié)調(diào)。

5 研究結(jié)果 Findings

The result of this research have shown: a) the problems that cause inefficient coordination during the design process of construction documents is lack of enough details for different disciplines and is lack of reference name for others to make correction, b) well-coordinated design documents can reduce errors during construction stage to ensure the delivery time and c) BIM model in LOD 350 can simulate each building components in such high level of detail, where design teams can improve spatial design optimization. (Figure 13) Illustrated the role and function of LOD 350 during construction documents design phase. Adoption of LOD 350 during BIM implementation can help design team and construction team to make better project and design review, which can reduce project uncertainties and help its successful delivery. In addition, this collaborative culture will be enhanced because team members to spend more time together to review the digital representation of a project and thus their knowledge level and understanding of the project will be improved significantly. Though, more important is that LOD 400 will be more accurate, therefore, the implementation of construction process will be more effective. In addition, when Asset Information Modelling (AIM) will be submitted to the client for use, it will contain more "accurate" building information that can be managed or modified based on the needs of the project investor.

圖13 LOD 350 的作用與角色Fig.13 Role and Function of LOD 350

本文的研究結(jié)果表明：a) 導(dǎo)致施工圖設(shè)計(jì)階段低效協(xié)調(diào)的主要原因是各專業(yè)缺少足夠的信息參考細(xì)節(jié)，并且缺少能提供其它專業(yè)進(jìn)行修改的參考名稱；b) 在施工的過程中，充分協(xié)調(diào)的設(shè)計(jì)圖紙能夠幫助施工減少錯誤來確保項(xiàng)目的按時竣工；c) LOD 350階段的BIM模型能夠針對項(xiàng)目的構(gòu)件進(jìn)行高精度的模擬，所以設(shè)計(jì)團(tuán)隊(duì)可以有效提高空間優(yōu)化的能力。圖13展示了LOD 350 在施工圖設(shè)計(jì)階段的角色和作用, 在建設(shè)項(xiàng)目的BIM應(yīng)用中采納LOD 350能使設(shè)計(jì)方和施工方對建設(shè)項(xiàng)目做出更好的評估來有效降低項(xiàng)目施工中的不確定性，以確保項(xiàng)目的按時竣工。另外，通過這種方式，團(tuán)隊(duì)的協(xié)同合作環(huán)境將會被有效提高，因?yàn)閳F(tuán)隊(duì)成員會投入更多時間來一起對項(xiàng)目的BIM模型進(jìn)行審閱，所以設(shè)計(jì)團(tuán)隊(duì)將會顯著提升對項(xiàng)目的認(rèn)知與了解。最重要的是，通過LOD 350的應(yīng)用，LOD 400級別的BIM模型將能夠更加精確地建立來更好地幫助施工過程的高效實(shí)施。此外，當(dāng)建立資產(chǎn)信息模型(AIM)并且進(jìn)行交付的同時，模型能夠針對甲方的需求來提供更多精確的項(xiàng)目信息，為建筑后期的運(yùn)營提供有效支持。

6 結(jié)論和下一階段研究 Conclusion and Future Studies

Since China has introduced LOD 3.0 and LOD 4.0 in BIM Modelling process, still there is a gap on project delivery because quality level of information (LOD) is low and its quantity (Terabyte) can lead to such as: mismatch information, not accurate data, incorrect files names etc. As a result, project coordination is affected, and the project has more chances to fail.

國內(nèi)的BIM交付標(biāo)準(zhǔn)為建模過程制定了LOD 3.0和LOD 4.0，但是在這兩個標(biāo)準(zhǔn)之間存在著空缺。因?yàn)樵谠O(shè)計(jì)過程中信息深度(LOD)的不足以及信息量(太字節(jié))的不足會導(dǎo)致一些問題，比如：信息搭配錯誤，不精確的數(shù)據(jù)，不正確的文件名稱等。所以，項(xiàng)目設(shè)計(jì)的協(xié)同合作會受到影響，并且會導(dǎo)致項(xiàng)目產(chǎn)生更大幾率的失敗。

Considering the impact of applying LOD 350 in a project in Ningbo China, results shown its success to eliminate the above errors. Consequently, this idea (LOD 3.5) could be introduced and practiced in both national and provincial level.

考慮到在實(shí)際項(xiàng)目的實(shí)踐中采用LOD 350標(biāo)準(zhǔn)的作用，研究結(jié)果表明這個標(biāo)準(zhǔn)能夠成功消除上述在設(shè)計(jì)協(xié)同合作上的問題。所以，LOD 3.5 適合被加入LOD 3.0與LOD 4.0之間，并且在國家級與省級的標(biāo)準(zhǔn)中進(jìn)行推廣和實(shí)踐。

However more studies must be conducted to provide a more comprehensive understanding of its implementation within AEC enterprises and construction projects. Moreover, beyond the contribution of this research in policy level, the team can foresee also huge impact in projects′ performance due to the need to design, construct and operate buildings in a more integrated and collaborative manner.

但是，這需要進(jìn)行更多的研究來全面了解這個標(biāo)準(zhǔn)將如何在建筑、工程、施工企業(yè)和建設(shè)項(xiàng)目中實(shí)施。更多的是，這個研究除了在標(biāo)準(zhǔn)制定層面進(jìn)行論證之外，研究團(tuán)隊(duì)預(yù)測到，在項(xiàng)目執(zhí)行的過程中，對整合設(shè)計(jì)和協(xié)同合作需求的提升將會極大改善項(xiàng)目的績效。

As a result, the future of BIM in China would be the introduction of LOD 3.5 where stakeholders can coordinate project information (graphical, non-graphical and documentation) in a more holistic perspective, based also on ISO 19650 that is the latest internationally recognised standard/policy in building information modelling and management.

因此，未來的國內(nèi)BIM標(biāo)準(zhǔn)如果推出LOD 3.5，基于國際標(biāo)準(zhǔn)化組織在BIM建模和管理上最新推出的ISO 19650，項(xiàng)目各參與方可以對項(xiàng)目的信息(圖像信息、非圖像信息、文件)從整體的視角進(jìn)行協(xié)調(diào)。

In this occasion China is entering more in the international market dynamically because those enterprises are part of BIM driven projects can meet clients′ requirements based on time, cost, and quality.

借助這個機(jī)會，中國建筑企業(yè)能夠更加充滿活力地進(jìn)入國際市場，因?yàn)檫@些企業(yè)將能夠更好地對項(xiàng)目進(jìn)行基于BIM的管理，來滿足業(yè)主方對時間、成本和質(zhì)量上的要求。