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Proposing a Quality Inspection Process Model Using Advanced Technologies for the Transition to Smart Building Construction

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With advancements in new technologies in the industry, efforts have been made to adopt various smart devices during the life cycle of building construction. However, little attention has been paid to developing a work process model to maximize the benefits of smart technologies. While identifying the shortcomings of conventional quality inspection, this study configures a new quality inspection process model in collaboration with smart devices. Based on the proposal, the study developed a new tool that effectively improves the current quality inspection practice. The final goal of this research is to propose a novel inspection process model by developing an Application Programming Interface (API) system using Building Information Model (BIM) software. Additionally, to verify the applicability of the system, this study includes a case study on tile work and confirms the effects of a prototype of the proposed system through an expert survey. The survey results reveal that the proposed system is effective and practical. This research contributes to maximizing the effectiveness of using smart devices and supporting effective application in smart construction.
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Citation: Shin, H.-J.; Cha, H.-S.
Proposing a Quality Inspection
Process Model Using Advanced
Technologies for the Transition to
Smart Building Construction.
Sustainability 2023,15, 815. https://
doi.org/10.3390/su15010815
Academic Editor: Ali
Bahadori-Jahromi
Received: 1 December 2022
Revised: 19 December 2022
Accepted: 20 December 2022
Published: 2 January 2023
Copyright: © 2023 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
sustainability
Article
Proposing a Quality Inspection Process Model Using Advanced
Technologies for the Transition to Smart Building Construction
Hyeon-Ju Shin and Hee-Sung Cha *
Department of Architectural Engineering, Ajou University, Suwon 16499, Republic of Korea
*Correspondence: hscha@ajou.ac.kr
Abstract:
With advancements in new technologies in the industry, efforts have been made to adopt
various smart devices during the life cycle of building construction. However, little attention has
been paid to developing a work process model to maximize the benefits of smart technologies. While
identifying the shortcomings of conventional quality inspection, this study configures a new quality
inspection process model in collaboration with smart devices. Based on the proposal, the study
developed a new tool that effectively improves the current quality inspection practice. The final
goal of this research is to propose a novel inspection process model by developing an Application
Programming Interface (API) system using Building Information Model (BIM) software. Additionally,
to verify the applicability of the system, this study includes a case study on tile work and confirms
the effects of a prototype of the proposed system through an expert survey. The survey results reveal
that the proposed system is effective and practical. This research contributes to maximizing the
effectiveness of using smart devices and supporting effective application in smart construction.
Keywords:
application programming interface (API); building information modeling (BIM); construction
quality inspection; smart building construction; smart technologies
1. Introduction
1.1. Research Background
In recent years, with advancements in new technologies in the construction industry,
many tasks have been digitalized and automated through the use of smart technologies
to improve the quality and efficiency of building projects [
1
4
]. Attempts have been
made to use Building Information Modeling (BIM) with various new technologies, such as
Artificial Intelligence (AI), Augmented Reality (AR)/Virtual Reality (VR), Light Detection
and Ranging (LiDAR) and other smart sensors [
5
8
]. Linking BIM with various smart
technologies, many construction works have shifted from a manual to a digital process.
These changes are occurring in each stage of construction projects, from the planning,
design and construction to the maintenance stages [
9
12
]. Although many countries have
established guidelines for the effective application of BIM at the planning and design stages,
the level of integration between BIM and smart technologies in construction is still lacking.
Automated methods linking BIM with smart technologies at the construction stage have
long been proposed, but even simple inspection work is still conducted using a manual
approach and paper documents [13,14].
One of the important factors hindering the application of BIM and smart technologies
in construction is the lack of a “how-to” process model in relation to the adoption of BIM and
smart technologies [
15
,
16
]. Sun et al. (2017) categorized five factors impeding the adoption
of new technologies: technology, cost, management, personnel and legal factors [
17
]. The
management factor, which includes the absence of a process model, practical application
strategies and standards that change when BIM is adopted in construction, had the most
significant impact compared to the other factors.
A collaboration of BIM and smart technologies has been gradually introduced at
the construction stage to address the aforementioned factors while implementing smart
Sustainability 2023,15, 815. https://doi.org/10.3390/su15010815 https://www.mdpi.com/journal/sustainability
Sustainability 2023,15, 815 2 of 21
technologies and raising the standard of the construction industry [
18
22
]. At this stage,
quality inspection is a simple and repetitious process. However, if ignored, it negatively
affects the efficiency and quality of a project. Many studies have already been conducted on
integrating BIM with smart technologies to increase performance [2327]. However, most
of these studies have dealt with particular work items without any appropriate “how-to”
process model acceptable in current practice. This is also because of the absence of real-
world usage cases of the many technologies that can be incorporated into quality control
during the construction stage.
The obstacles to new technology adoption should be eliminated in order to integrate
BIM-based smart technologies. Consequently, it is necessary to establish a new process
model for practical application that may change with the adoption of smart technologies.
Therefore, this research aims to propose a new “how-to” process model for adopting
BIM and smart technologies to increase the performance of quality control during the
construction stage. Furthermore, this study seeks to verify the effectiveness of the proposed
model by conducting a case study to demonstrate its practical application.
1.2. Literature Review
1.2.1. Smart Technologies in Building Construction
In recent times, smart technologies have been applied and connected with BIM in vari-
ous areas of building construction. They have been applied not only to quality management
but also to schedule and safety management. Smart technologies have, thus, contributed to
improved efficiency and productivity in the construction industry.
In terms of schedule management, Ratajczak et al. (2019) defined and used material
information in BIM and provided details of the construction method in smartphone ap-
plication in conjunction with AR to support easier work progress [
28
]. This enabled us to
check the precision rate through object tracking, resulting in an improvement in on-site
productivity. Tran et al. (2021) leveraged the LiDAR point-cloud-based digital twin model
available in prefabricated construction (PC) to monitor the construction schedule [
29
]. By
comparing plans with actual progress, an automatic analysis was obtained in the material
delivery and installation process. Hamledari et al. (2021) provided an algorithm to identify
locations that require inspection by linking unmanned aerial service (UAS) with the BIM
model. Additionally, the inspection work items were recorded and the work progress rate
can be obtained on a real-time basis [30].
With regard to safety management, Zhang et al. (2015) developed a spatial-model-
based safety-planning tool using a workspace visualization model in BIM via a global
positioning system (GPS) logger [
31
]. They provided a GPS sensor-based monitoring
support system to improve the safety of construction workers. This enables us to effec-
tively check whether workers are wearing safety hats. Wang et al. (2017) used radio
frequency identification (RFID) to provide material tracking using real-time supply man-
agement, thereby ensuring the timely availability of the required materials, which resulted
in timely delivery, by minimizing lead time and contributing to improvements in con-
struction productivity [
32
]. Du et al. (2018) presented a project collaboration model using
collaborative virtual reality (CoVR), which is a cloud-based multi-user VR system for
coordination management [
33
]. They created an interactive VR environment through voice
sharing between collaborators and contributed to increased communication efficiency in the
construction process.
From the quality management perspective, Kim et al. (2016) developed a contactless
dimensional quality assurance (DQA) technique by applying a laser scanner in conjunction
with the BIM model to check the key parameters of the precast concrete automatically
and precisely [
34
]. This improved quality control efficiency in the structural work process.
Golparvar-Fard et al. (2015) and Kim et al. (2020) used a computer vision technique to
analyze 3D point cloud data obtained from LiDAR-installed UAS [
35
,
36
]. They collected
the data necessary to document the work in progress from any unorganized construction
photographic data. Comparing the BIM with the actual data, they proved that the new
Sustainability 2023,15, 815 3 of 21
approach has the potential to achieve effective quality management. Kwon et al. (2014)
suggested a defect management (DM) tool, combining the BIM and AR devices for on-site
quality control in reinforced concrete work [
37
]. With the development of an image-
matching process, job-site management became more effective and faults were reduced
significantly. Ma et al. (2018) conducted research on an indoor positioning algorithm,
whereby an automatic quality checklist was extracted and transmitted via a BIM, which
simplified the inspection process [
38
]. By including the check-listed items in the automatic
extraction process, susceptibility to omissions and mistakes in the conventional inspection
process was reduced.
In the current inspection practice, on-site quality data are obtained through various
data collection tools, i.e., tape measure, thermometer and manometer, and analyzed in
terms of whether the quality criteria are met by comparing the data with the design criteria.
Defect inspection has long been the focus of smart construction technology, and research is
now being conducted to assist defect judgment using the BIM to find any faults based on 3D
point cloud data and to configure the data set obtained by the advanced technologies [
39
,
40
].
To efficiently execute quality control using BIMs, research was conducted on the creation
of add-in software embedded in the BIM models [
41
43
]. However, as mentioned in the
previous section, the technological application strategy in the quality inspection process
has not been thoroughly established, despite a variety of smart technologies being actively
adopted in the construction industry.
1.2.2. Preliminary Findings from Literature Review
The quality of construction work is influenced by a variety of factors, such as labor
skillfulness, work environment and the management system, making it difficult to propose
a standardized work process model. In the case of quality inspection, where there exists
an established procedure, previous studies have focused on a particular work type and
proposed replacing the existing work process with smart devices and/or equipment. The
current work process can be improved by making the most of new technologies. Although
there are various ways to acquire data for each type of work in quality inspection, it is
difficult to designate one type of data collection. Therefore, most research on inspection
deals with the technical part of data processing. Moreover, research that proposes a
new technology for quality inspection does not deal with the overall process of quality
inspection but only with the specific application of data acquired through various smart
devices. Specifically, there is still insufficient research on the implementation of the quality
inspection process from the beginning (planning) to the final (reporting) stage. There exists
a limitation in that project managers who implement quality inspections on site do not
know how to apply these new work practices in using the new technologies.
Therefore, it is necessary to develop a new work process model using BIM and smart
technologies that can be applied to the overall quality inspection practice, both during and
after project execution. Based on this research gap, this study developed an application
programming interface (API) using the BIM tool Revit
TM
. This tool can improve the overall
quality inspection process that is linked with smart construction devices. Furthermore,
the authors verified the effectiveness of the new process via a real case study project to
enhance the adoption of smart technologies in the quality inspection process within the
BIM system environment.
2. Research Methods
This study consists of three main phases: Phase I: proposing a new quality inspection
process model; Phase II: developing a quality inspection-assisted system and Phase III: a
case study on the new process model and validation. Details of each phase are depicted in
Figure 1.
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2. Research Methods
This study consists of three main phases: Phase I: proposing a new quality inspection
process model; Phase II: developing a quality inspection-assisted system and Phase III: a
case study on the new process model and validation. Details of each phase are depicted
in Figure 1.
Figure 1. Research methodology.
Phase I of this study involves the adoption of smart technologies and proposes a new
construction quality inspection process in comparison with the conventional inspection
process in order to guarantee the quality criteria. In Phase II, the construction quality in-
spection-assisted system prototype was developed using the established construction
quality inspection process. At present, the developed add-in system consists of four func-
tions required at each stage of the quality inspection process, including quality inspec-
tion form, “quality data,quality trackingand “group messenger.In Phase III, after
selecting a particular work type, such as tile work, the new process model was incorpo-
rated into the tile work inspection process. This real case study was carried out based on
the proposed system. At this phase, a questionnaire survey was conducted to validate the
effectiveness of the proposed model using the API system. In developing a construction
quality inspection system, both RevitTM 2019 and Visual StudioTM 2022 were used. In the
case study, Leica BLK360 was used as a smart device. BLK360 supports both high dynamic
range (HDR) and thermal image and acquires 3D point cloud data required for tile con-
struction quality inspection to measure the appropriateness of tile installation.
3. Proposing a New Quality Inspection Process (Phase )
The conventional quality inspection process was scrutinized to identify the barriers
that may be removed by the adoption of smart technologies. This section proposes a new
quality inspection process in collaboration with new technologies.
3.1. Process Mapping of Current Construction Quality Inspection
The current work process model for construction quality inspection was recognized.
At the task-planning stage, a quality inspection plan is provided. Then, the work instruc-
tions are given to the laborers and on-site monitoring is carried out by project managers.
After the assigned work is completed, an on-site quality check is conducted to evaluate
whether the quality of the work is satisfactory. At this stage, the quality inspection check-
list is used to assess the quality criteria. Project managers typically bring paper drawings
and checklists to the jobsite and compare design elements with the actual installation. This
process is traditionally carried out by on-site monitoring with a checklist when an inspec-
tion request occurs. When the construction quality does not meet the quality standards,
Figure 1. Research methodology.
Phase I of this study involves the adoption of smart technologies and proposes a new
construction quality inspection process in comparison with the conventional inspection
process in order to guarantee the quality criteria. In Phase II, the construction quality
inspection-assisted system prototype was developed using the established construction
quality inspection process. At present, the developed add-in system consists of four
functions required at each stage of the quality inspection process, including “quality
inspection form,” “quality data,” “quality tracking” and “group messenger.” In Phase
III, after selecting a particular work type, such as tile work, the new process model was
incorporated into the tile work inspection process. This real case study was carried out
based on the proposed system. At this phase, a questionnaire survey was conducted to
validate the effectiveness of the proposed model using the API system. In developing a
construction quality inspection system, both Revit
TM
2019 and Visual Studio
TM
2022 were
used. In the case study, Leica BLK360 was used as a smart device. BLK360 supports both
high dynamic range (HDR) and thermal image and acquires 3D point cloud data required
for tile construction quality inspection to measure the appropriateness of tile installation.
3. Proposing a New Quality Inspection Process (Phase I)
The conventional quality inspection process was scrutinized to identify the barriers
that may be removed by the adoption of smart technologies. This section proposes a new
quality inspection process in collaboration with new technologies.
3.1. Process Mapping of Current Construction Quality Inspection
The current work process model for construction quality inspection was recognized. At
the task-planning stage, a quality inspection plan is provided. Then, the work instructions
are given to the laborers and on-site monitoring is carried out by project managers. After the
assigned work is completed, an on-site quality check is conducted to evaluate whether the
quality of the work is satisfactory. At this stage, the quality inspection checklist is used to
assess the quality criteria. Project managers typically bring paper drawings and checklists
to the jobsite and compare design elements with the actual installation. This process is
traditionally carried out by on-site monitoring with a checklist when an inspection request
occurs. When the construction quality does not meet the quality standards, the laborer
has to be instructed to remedy the work. Otherwise, a quality inspection report has to be
presented and recorded in a paper-based format. Details of this current process, mapping
the quality inspection, are depicted in Figure 2.
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the laborer has to be instructed to remedy the work. Otherwise, a quality inspection report
has to be presented and recorded in a paper-based format. Details of this current process,
mapping the quality inspection, are depicted in Figure 2.
Figure 2. Current process map of construction quality management.
As seen in Figure 2, the current quality management process has three steps, including
task planning, on-site construction and inspection and document management. At each
step, the participants, i.e., the supervisor, inspector and worker, are requested to perform
their tasks. At the construction jobsite, each work item is initially carried out in accordance
with the construction execution plan during the construction and inspection phases, and
performance quality is checked and examined periodically. During the construction and in-
spection stage, the work is verified twice by the inspector and supervisor. Once this verifi-
cation is conducted, paper records of the work are drawn up at the documentation step.
When comparing the constructed work with the original plan to match the quality criteria,
the subject work item is deemed satisfactory if no quality problem is detected.
The inspection checklist, which is used to verify whether the constructed work meets
quality standards, includes measurement and judgment items in relation to the design
drawings, specifications, supervision guidelines and inspection manuals. In general, the
jobsite construction is carried out according to this checklist. The inspection checklist deals
with material/equipment management and detailed construction methods that are not
specified in the construction drawings.
Since it includes all the details necessary for construction quality management, the
inspection can easily be conducted during the supervision stage. For instance, the inspec-
tion checklist for concrete formwork includes determining whether the form is installed
according to the construction guidelines as well as examining whether it is built based on
the formwork safety rules and regulations. The inspectors are required to check whether
the intervals of the support material installation and deflection of the form are within the
quality allowance. The maximum value of the allowable deflection is specified to be three
millimeters (mm) according to the guidelines of the construction formwork installation.
Likewise, in the case of concrete placement, a construction plan must be provided so that
inspection items can be added in order to check whether the construction was conducted
according to the inspection checklist.
The shortcomings of the current quality inspection process can be summarized as
follows:
(1) Many documents used in the inspection are provided in a paper-based format. Main-
taining these paper records is troublesome and error prone. Furthermore, if stake-
holders need a particular document, they must review numerous documents to find
the required one, which reduces work efficiency. As indicated in Figure 2, all docu-
ments from the task-planning stage to the documentation stage, as well as the
Figure 2. Current process map of construction quality management.
As seen in Figure 2, the current quality management process has three steps, including
task planning, on-site construction and inspection and document management. At each
step, the participants, i.e., the supervisor, inspector and worker, are requested to perform
their tasks. At the construction jobsite, each work item is initially carried out in accordance
with the construction execution plan during the construction and inspection phases, and
performance quality is checked and examined periodically. During the construction and
inspection stage, the work is verified twice by the inspector and supervisor. Once this
verification is conducted, paper records of the work are drawn up at the documentation
step. When comparing the constructed work with the original plan to match the quality
criteria, the subject work item is deemed satisfactory if no quality problem is detected.
The inspection checklist, which is used to verify whether the constructed work meets
quality standards, includes measurement and judgment items in relation to the design
drawings, specifications, supervision guidelines and inspection manuals. In general, the
jobsite construction is carried out according to this checklist. The inspection checklist deals
with material/equipment management and detailed construction methods that are not
specified in the construction drawings.
Since it includes all the details necessary for construction quality management, the
inspection can easily be conducted during the supervision stage. For instance, the inspec-
tion checklist for concrete formwork includes determining whether the form is installed
according to the construction guidelines as well as examining whether it is built based on
the formwork safety rules and regulations. The inspectors are required to check whether
the intervals of the support material installation and deflection of the form are within the
quality allowance. The maximum value of the allowable deflection is specified to be three
millimeters (mm) according to the guidelines of the construction formwork installation.
Likewise, in the case of concrete placement, a construction plan must be provided so that
inspection items can be added in order to check whether the construction was conducted
according to the inspection checklist.
The shortcomings of the current quality inspection process can be summarized
as follows:
(1)
Many documents used in the inspection are provided in a paper-based format. Main-
taining these paper records is troublesome and error prone. Furthermore, if stakehold-
ers need a particular document, they must review numerous documents to find the
required one, which reduces work efficiency. As indicated in Figure 2, all documents
from “the task-planning stage” to “the documentation stage”, as well as the inspection
documents at the on-site construction and inspection stage, must be prepared and
created in paper format. As the instructions for rework after the site inspection are
also given in paper format, it is difficult to give immediate feedback, which further
reduces work efficiency.
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(2)
It is important to decide, based on the findings from a visual inspection, whether the
final inspection standards have been met at the time of on-site inspection. Even if
high-tech measuring systems are used to check the quality level, it is still difficult to
avoid erroneous measurement and inaccurate judgment. A drawback of the current
inspection approach is the possibility of causing a defect in the construction work.
(3)
Due to unspecified inspection areas, it is difficult to recognize the exact amount of
construction quantity required. Moreover, it requires additional time and effort. The
laborers only carry out construction work that is called for, so there is no obligation to
rework the parts that are not called for. Due to these aspects of the current practice, the
inspector or supervisor must inspect the entire site and identify problematic locations
before making a request. If the location where the construction quality in question is
not specified, inspection of all work quantities is essential. Therefore, the request for
reconstruction is inefficient and time consuming.
3.2. Process Mapping of Construction Quality Inspection Using Smart Technologies
To solve the aforementioned problems, the authors propose a new quality inspection
process using smart construction technologies that support various types of work. This
approach is helpful in improving the current quality control system that is mainly depen-
dent on manual inspection. Figure 3depicts a new quality inspection process proposed
in this research.
Sustainability 2023, 14, x FOR PEER REVIEW 6 of 22
inspection documents at the on-site construction and inspection stage, must be pre-
pared and created in paper format. As the instructions for rework after the site in-
spection are also given in paper format, it is difficult to give immediate feedback,
which further reduces work efficiency.
(2) It is important to decide, based on the findings from a visual inspection, whether the
final inspection standards have been met at the time of on-site inspection. Even if
high-tech measuring systems are used to check the quality level, it is still difficult to
avoid erroneous measurement and inaccurate judgment. A drawback of the current
inspection approach is the possibility of causing a defect in the construction work.
(3) Due to unspecified inspection areas, it is difficult to recognize the exact amount of
construction quantity required. Moreover, it requires additional time and effort. The
laborers only carry out construction work that is called for, so there is no obligation
to rework the parts that are not called for. Due to these aspects of the current practice,
the inspector or supervisor must inspect the entire site and identify problematic lo-
cations before making a request. If the location where the construction quality in
question is not specified, inspection of all work quantities is essential. Therefore, the
request for reconstruction is inefficient and time consuming.
3.2. Process Mapping of Construction Quality Inspection Using Smart Technologies
To solve the aforementioned problems, the authors propose a new quality inspection
process using smart construction technologies that support various types of work. This
approach is helpful in improving the current quality control system that is mainly de-
pendent on manual inspection. Figure 3 depicts a new quality inspection process pro-
posed in this research.
Figure 3. A new process map of construction quality inspection using smart technologies.
The three-step process is similar to the conventional process. However, the detailed
execution contents of each step are different in Figure 3. In the task-planning stage, the
supervisor makes a construction and inspection plan for the work type in progress and
creates an inspection checklist for the BIM elements related to the particular subject work
type. During the on-site construction and inspection stage, the construction work is car-
ried out according to the predetermined construction plan. After completing execution,
the work is confirmed as completed using smart technologies. The preliminary inspection
is performed at the worker level. Both inspector-level and supervisor-level inspections
follow once the worker-level inspection is completed. The highlighted part in Figure 3
indicates this difference. The inspections performed by the inspector and supervisor judge
whether the quality of construction deliverables is satisfactory. However, the worker-level
inspection saves time that is wasted in requesting inspections, minor inspections and re-
construction, before confirming the construction quality. In contrast to the planning stage,
smart technologies are used in generating inspection results and are automatically stored
in the BIM server.
Figure 3. A new process map of construction quality inspection using smart technologies.
The three-step process is similar to the conventional process. However, the detailed
execution contents of each step are different in Figure 3. In the task-planning stage, the
supervisor makes a construction and inspection plan for the work type in progress and
creates an inspection checklist for the BIM elements related to the particular subject work
type. During the on-site construction and inspection stage, the construction work is carried
out according to the predetermined construction plan. After completing execution, the
work is confirmed as completed using smart technologies. The preliminary inspection
is performed at the worker level. Both inspector-level and supervisor-level inspections
follow once the worker-level inspection is completed. The highlighted part in Figure 3
indicates this difference. The inspections performed by the inspector and supervisor judge
whether the quality of construction deliverables is satisfactory. However, the worker-level
inspection saves time that is wasted in requesting inspections, minor inspections and re-
construction, before confirming the construction quality. In contrast to the planning stage,
smart technologies are used in generating inspection results and are automatically stored
in the BIM server.
A new quality inspection process proposed in this research contributes to solving the
problems present in the current quality inspection process. The key elements are as follows:
(1)
The vast amounts of documents used throughout the inspection process are archived
and available on the BIM server. These are easier to manage, as they are digitally
Sustainability 2023,15, 815 7 of 21
stored in an electronic file format. Thus, the inspection efficiency is improved, as
there is no need to search for files, because the relevant data are linked with the BIM
model. There is also no need to prepare documents, such as specifications or drawings,
when conducting an on-site inspection, as the data can be easily obtained using smart
technologies. Using the BIM, construction inspectors can log in to the program instead
of transferring documents in a written format and work-related feedback, such as
reconstruction work instruction is given immediately using a communication system,
which improves work efficiency.
(2)
Quality data are acquired using smart technologies and the pass/fail decision can
be made on a real-time basis as the data can be obtained and analyzed in the BIM.
The accuracy level is higher than inspecting with manual detection. In addition,
most smart technologies acquire quality data in a non-destructive way, which has
advantages over traditional methods.
(3)
As shown in Figure 3, temporary rework can be executed immediately, and the loca-
tion in need of inspection is designated by adding an inspection spot at the worker
level. This process can expedite inspectors’ and supervisors’ checks of the target
workspace when an inspection is requested. By specifying the locations where a prob-
lem of quality has occurred, the current inspection practice is much improved. The
new inspection process can tremendously save time wasted in inspection preparation,
on-site inspections and rework requests, when compared to the current process.
4. Developing a Quality Inspection-Assisted API (Phase II)
To effectively carry out each task in the construction quality inspection process, as
proposed in Phase I, the authors developed an assisted tool, API, that supports the new
inspection process. To conduct efficient construction quality inspection based on the BIM,
it is beneficial to use an application embedded in the BIM software. In addition, the
relationships among the functions within the system must be clarified so that they can be
effectively used in the construction quality inspection process.
4.1. Construction Quality Inspection API Architecture
The system architecture is provided in Figure 4. In this system, users are requested
to input relevant information in advance so that the BIM can provide users with the
appropriate information, i.e., drawings, specifications, quality checklists and inspection
areas. After the quality inspection plan is created, workers are instructed to begin their
job according to the construction drawings and specifications. Construction managers
can monitor the work status via on-site cameras. When the assigned work is completed,
quality data can be secured through smart devices available on site. However, the data
type, obtained by smart devices, should be linked to the relevant items in the checklist, or
the person responsible for confirming the relevant data should enter the same directly into
the checklist. In order to link the on-site data with the associated items in the checklist, it is
important to integrate smart devices with the BIM server. Without digital information, it is
difficult to determine whether the on-site data match the quality criteria within tolerance.
If the inspection lot is completed, a notification asking the supervisor to validate the
inspection is issued by the system. Next, the system sends a warning signal within the BIM
if the inspection does not meet the quality criteria; otherwise, it confirms the inspection
to be completed within quality standards. It is also possible to request for reconstruction
or re-inspection when needed, via instant messaging. Once all planned quantities have
been constructed and inspected correctly, the quality inspection checklist documents are
stored in the BIM server in a digital format for future usage. The add-in system architecture
supporting the execution of the corresponding processes is shown in Figure 4.
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stored in the BIM server in a digital format for future usage. The add-in system architecture
supporting the execution of the corresponding processes is shown in Figure 4.
Figure 4. Construction quality inspection system API architecture.
The add-in construction quality inspection that works within the BIM system consists
of four items: inspection form, quality data, quality tracking and group messenger. Each
component in the system is developed in a panel of the RevitTM. As seen in Figure 4, there
are four functions and each function consists of multiple modules generated by the system
buttons necessary to carry out the work.
The blue dotted line indicates “Quality standarddata flow; the purple dotted line
shows Construction site data flow; and the red dotted line means the flow of “BIM
model data. These three types of data are stored in the BIM server and used in the Con-
struction Quality Inspection system that created the add-in program via Revit. The pink
dotted line in the system indicates the flow of “quality inspection resultdata that are
generated via the interaction of the three types of data entered into the BIM server.
The quality standard data in Figure 4 are used to create an inspection form in the
“Create Form module and determine whether the quality standards have been met in
the “Load Data” module. Construction-site data through smart technologies are uploaded
into the BIM through the Load Work Data” module. Then, the data are moved to the
“Load Data” module and used to determine whether quality standards are met. The BIM
data that are stored in the BIM server while a model is created are matched with the con-
struction site data in the Load Work Data module and moved to the Load Data mod-
ule to determine whether the quality criteria have been met along with quality standard
data. The quality inspection result data, generated through the interaction between the
three types of data, move to the Create Formmodule when inspection results meet the
quality standards and are automatically reflected in the inspection form. Then, they are
reflected in the process progress rate through the Quality trackingmodule. On the other
hand, when quality standards are not met, they move to the Send Messagemodule and
are used to request rework by indicating the corresponding spot in the BIM.
Each module has a procedural relationship with a different module, but the “View
Data Moduleand the “Load Schedule Module consist of functions to view existing data
stored in the BIM database, indicating that there is no special procedural relationship. The
Figure 4. Construction quality inspection system API architecture.
The add-in construction quality inspection that works within the BIM system consists
of four items: inspection form, quality data, quality tracking and group messenger. Each
component in the system is developed in a panel of the Revit
TM
. As seen in Figure 4, there
are four functions and each function consists of multiple modules generated by the system
buttons necessary to carry out the work.
The blue dotted line indicates “Quality standard” data flow; the purple dotted line
shows “Construction site” data flow; and the red dotted line means the flow of “BIM model”
data. These three types of data are stored in the BIM server and used in the Construction
Quality Inspection system that created the add-in program via Revit. The pink dotted line
in the system indicates the flow of “quality inspection result” data that are generated via
the interaction of the three types of data entered into the BIM server.
The quality standard data in Figure 4are used to create an inspection form in the
“Create Form” module and determine whether the quality standards have been met in the
“Load Data” module. Construction-site data through smart technologies are uploaded into
the BIM through the “Load Work Data” module. Then, the data are moved to the “Load
Data” module and used to determine whether quality standards are met. The BIM data that
are stored in the BIM server while a model is created are matched with the construction site
data in the “Load Work Data” module and moved to the “Load Data” module to determine
whether the quality criteria have been met along with quality standard data. The quality
inspection result data, generated through the interaction between the three types of data,
move to the “Create Form” module when inspection results meet the quality standards and
are automatically reflected in the inspection form. Then, they are reflected in the process
progress rate through the “Quality tracking” module. On the other hand, when quality
standards are not met, they move to the “Send Message” module and are used to request
rework by indicating the corresponding spot in the BIM.
Each module has a procedural relationship with a different module, but the “View
Data Module” and the “Load Schedule Module” consist of functions to view existing data
stored in the BIM database, indicating that there is no special procedural relationship. The
construction quality inspection API is characterized by the fact that both the beginning and
ending modules are placed in the “inspection form” and the modules for “quality data”
are at the center of the system. In addition, the flow among the modules of this system
Sustainability 2023,15, 815 9 of 21
is closely related to the construction quality inspection process, after the adoption of the
smart technologies, as proposed in Phase I.
4.2. Developing a Quality Inspection System Prototype
In this research, the authors used Visual Studio
TM
2022 to develop an add-in-type
construction quality inspection system via the BIM software Revit
TM
. Based on the new
quality inspection work procedure defined earlier, a new toolbar with panels and buttons
was generated and applied to similar construction quality inspection processes. In this
case, the construction quality inspection API can be customized to the relevant work types.
Figure 5shows an exemplary graphic user interface (GUI) developed for the case study
described in the next section.
Sustainability 2023, 14, x FOR PEER REVIEW 9 of 22
construction quality inspection API is characterized by the fact that both the beginning
and ending modules are placed in the “inspection formand the modules for quality
data” are at the center of the system. In addition, the flow among the modules of this
system is closely related to the construction quality inspection process, after the adoption
of the smart technologies, as proposed in Phase I.
4.2. Developing a Quality Inspection System Prototype
In this research, the authors used Visual StudioTM 2022 to develop an add-in-type
construction quality inspection system via the BIM software RevitTM. Based on the new
quality inspection work procedure defined earlier, a new toolbar with panels and buttons
was generated and applied to similar construction quality inspection processes. In this
case, the construction quality inspection API can be customized to the relevant work
types. Figure 5 shows an exemplary graphic user interface (GUI) developed for the case
study described in the next section.
Figure 5. An exemplary GUI of the quality inspection system.
As seen in Figure 5, the corresponding system prototype consists of four main fea-
tures: (1) The quality inspection formmenu supports the creation of a new inspection
checklist necessary for post-construction quality control or to confirm an existing inspec-
tion checklist. (2) The quality data” menu enables the management of necessary image
and sensor data information, such as thermal images, RGB images and 3D point clouds,
collected for quality control in the BIM. (3) The “quality trackingmenu makes it possible
to check the construction progress rate based on the amount of work passed during qual-
ity control and the ratio of problem-prone constructions during the entire construction
process, according to each work item. (4) The “group messenger menu expedites com-
munication among project members by explaining reconstruction areas, work details and
other quality issues. Under these four menu bars, each sub-function is grouped in the sys-
tem with the corresponding buttons to be operated. The programming code for system
GUI development is shown in Figure 6.
Figure 5. An exemplary GUI of the quality inspection system.
As seen in Figure 5, the corresponding system prototype consists of four main
features: (1) The “quality inspection form” menu supports the creation of a new
inspection checklist necessary for post-construction quality control or to confirm an
existing inspection checklist. (2) The “quality data” menu enables the management of
necessary image and sensor data information, such as thermal images, RGB images
and 3D point clouds, collected for quality control in the BIM. (3) The “quality tracking”
menu makes it possible to check the construction progress rate based on the amount
of work passed during quality control and the ratio of problem-prone constructions
during the entire construction process, according to each work item. (4) The “group
messenger” menu expedites communication among project members by explaining
reconstruction areas, work details and other quality issues. Under these four menu
bars, each sub-function is grouped in the system with the corresponding buttons to be
operated. The programming code for system GUI development is shown in Figure 6.
Sustainability 2023,15, 815 10 of 21
Sustainability 2023, 14, x FOR PEER REVIEW 10 of 22
Figure 6. Programming code for developing system GUI.
The add-in system was developed in the form of an external application. Tabs and
panels were programmed as menus using RevitTM developer package code. It is set that
the system operates at the same time as the RevitTM is executed. Table 1 details the four
menu items and their sub-functions.
Table 1. Description of display menu and buttons in the API system.
Menu
Button
Function
(1) Quality
inspection
form
Create form To create and prepare a checklist for quality control of
the corresponding work item
View form To archives and visualize the completed checklist data
(2) Quality
data
Load work data To uploads BIM -linked quality data
Load data To upload quality measurement into the BIM model ele-
ments
View data To check the quality measurement data stored in the
BIM mode
(3) Quality
tracking
Quality tracking
To check the progress of the selected work based on the
quality control results
Create new sheet
To create a new schedule for checking the progress
Load sheet To check the progress of the total project in quality con-
trol
(4) Group
messenger
Send message To send a request for work among the project group
members
My message To review messages received from others
In implementing the smart quality inspection process, the key functions are operated
using the quality inspection formand the quality data” menus. For each button gener-
ated on the system interface, the authors enabled users to check the content of their work
Figure 6. Programming code for developing system GUI.
The add-in system was developed in the form of an external application. Tabs and
panels were programmed as menus using Revit
TM
developer package code. It is set that
the system operates at the same time as the Revit
TM
is executed. Table 1details the four
menu items and their sub-functions.
Table 1. Description of display menu and buttons in the API system.
Menu Button Function
(1) Quality inspection form Create form To create and prepare a checklist for quality control of the
corresponding work item
View form To archives and visualize the completed checklist data
(2) Quality data
Load work data To uploads BIM -linked quality data
Load data To upload quality measurement into the BIM model elements
View data
To check the quality measurement data stored in the BIM mode
(3) Quality tracking
Quality tracking
To check the progress of the selected work based on the quality
control results
Create new sheet To create a new schedule for checking the progress
Load sheet To check the progress of the total project in quality control
(4) Group messenger Send message To send a request for work among the project group members
My message To review messages received from others
In implementing the smart quality inspection process, the key functions are operated
using the “quality inspection form” and the “quality data” menus. For each button gener-
ated on the system interface, the authors enabled users to check the content of their work
by clicking the corresponding button under the menu, so that they can easily use each
command function. The detailed code to make the button work is as follows (see Figure 7).
Sustainability 2023,15, 815 11 of 21
Sustainability 2023, 14, x FOR PEER REVIEW 11 of 22
by clicking the corresponding button under the menu, so that they can easily use each
command function. The detailed code to make the button work is as follows (see Figure
7).
Figure 7. Detailed code of "Create formand "Load work data” button.
Figure 7. Detailed code of "Create form” and "Load work data” button.
Sustainability 2023,15, 815 12 of 21
For the function requested when each button is clicked, the authors have programmed
the command code to run. For example, The “Create form” button is connected to Com-
mend1 as shown in mark
1
of Figure 7a, and the code for Commend1 is executed when
the corresponding button is clicked. Similarly, the “Load work data” button is linked to
Command2 in mark
2
of Figure 7a. Figure 7b,c show the detailed code of Command1
and 2. Command1 is programmed to generate a checklist interface when a command
is executed by linking it with the Inspection_Form document as shown in mark
a
(see
Figure 7b). In this way, by connecting Loadworkdata_Form document and Command2, it
is programmed to open the interface of uploading the quality data when a command is
operated as shown in mark b
(see Figure 7c).
In the same way as in Figure 7, each button works by being connected to the command
with a unique function. The operating principle of the system is applicable to general types
of construction and differs in data type and the interpretation of quality standards. Since
there is a difference in the form of data that can be acquired for each smart device, the
appropriate data form and smart technologies should be defined for each type of work.
In the following section, this research conducts a case study by selecting a tile work
to apply the new process developed in this study by defining the data type and the smart
device required for qulity inspection.
5. Case Study of the Proposed API System (Phase III)
5.1. Selection of Work Type and Checking Current Inspection Process
To reduce any quality flaws that emerge after construction and save maintenance costs
associated with errors, quality control plays an important role during the construction
process. The case study was chosen based on the level of importance of the construction
work. Kim et al. (2020) evaluated each work type considering the impact of defects in
building construction [
44
]. On calculating the defect importance rankings based on both
the frequency of defect occurrences and the maintenance of unit costs, tile work ranked
first. Therefore, this study selected tile work for the case study.
Prior to the proposal of a new quality inspection process for tile work, the current prac-
tice was reviewed. It is