Using Mobile Computing and Information Technology in Civil Engineering Construction Projects

Mobile computing technology has an enormous potential in civil engineering, mainly in the field of construction management. This paper presents an approach by using mobile computing in a civil engineering construction project, exploring how information can be exchanged at a construction site, and how billing of quantities (BOQ), drawings and specifications are shared for the benefit of the project. One of the major obstacles in using information technology (IT) when applied to civil engineering is due to the dynamic changes in the construction activities and the diversity of construction methods as compared to other industries. This has proved to be a great disadvantage when trying to give construction sites adequate IT support. Computers require infrastructure, which can be transferred easily to the head office, but rarely to the construction site itself in a systematic way. Therefore, the impact of IT on the way the construction industry actually works has not been significantly utilized. This paper consists of two main parts. The first part defines the concept of mobile computing, describes some recent research, and stresses the potential for the construction industry. The second part is focuses on an approach, implementing mobile computing in a real construction site.


An Overview of the Wireless Lan and Mobile Computing
Wireless LAN based mobile computing enables users to establish and maintain a wireless network connection throughout or between buildings, without the limitations of wires or cables Gast, (2003).With a WLAN, the covered area is analogous to a standard local area network.This might be a building or a campus environment, or even a small office or home environment.In large applications, by deploying a series of access points throughout a building or campus, you can achieve full coverage, providing the benefits of high-speed data rates, the freedom of mobility, and the ability to access broadband data anywhere within the local area network.Wireless LAN-solutions are becoming quite prevalent in many horizontal applications in the construction, general office and vertical industries, such as health care, manufacturing, universities and retail.Here are important but introductory facts about wireless LANs: wireless LAN adapter along with an antenna that resides in the mobile computer device (notebook or PDA) and an "Access Point" which acts as the hub and connects multiple mobile devices to a server.You can realistically support only 10-30 mobile devices per access point, depending on the network traffic.* When the 14 dB antennas are added, the outdoor wireless configuration is extended to 3.5 miles at an impressive 11 Mbps throughput.When combined with any third party 24 dB antenna, distances of 25 miles at 11 Mbps can be achieved.

Network Configuration
The access point's default configuration is as a root unit on a wired LAN.The other two possible roles, repeater unit and central unit in an all-wireless network, require specific changes to the default configuration.

Central Unit in an All-Wireless Network
In an all-wireless network, an access point acts as a stand-alone root unit.The access point is not attached to a wired LAN; it functions as a hub linking all stations

Repeater Unit that Extends Wireless Range
An access point can be configured as a stand alone repeater to extend the range of your infrastructure or to overcome an obstacle that blocks radio communication (Fig. 2).The repeater forwards traffic between wireless users and the wired LAN by sending packets either to another repeater or to an access point connected to the wired LAN (Fig. 3).

Mobile Computing Architecture
Wireless LAN consists of a hardware access point that generates wireless signals in a specific region (Fig. 3).PDA's Wireless notebook or cellelular devices are used to access the features.A user can access text/email, text/email, Web browsing and all internet features.The IEEE 802.1xProtocol is used in this technology.

Availability of Software and Hardware
Mobile computing fundamentally differs from desktop computing.Mobile devices including PDAs, mobile phones and digital cameras, when compared to desktop computers have low computational power, small memory and often no mass storage.Communication links to other mobile devices or to a stationary network are usually wireless.

Mobile Computing in Construction Industry
There are a number of project tasks that can be auto-mated in the construction industry -a few common examples are provided above.Some more applications are discussed in the following section.

Site Inspection in Construction Industry
Site inspection and project status reporting is considered as a high value mobile application by construction engineers because it reduces the number of site visits by supervising engineers by half or greater.While the construction industry has been slow in adopting mobile computing and automation in the field, things are changing quite fast now, since low-cost handheld devices are available and several construction automation applications have been developed by vendors.

Impact of Changes of Site Locations
It is a fact that the locations of construction sites frequently change which can cause a delay in collecting data from the field, and therefore produces a great need and importance for mobile computing.The field client not only collects data, but it also provides information to the progress engineer.The annual report by Daito (2000) mentioned four main benefits of the system: put devices where the user's hands are left free Xybernaut, (2000) (Fig. 5).The difficulty of controlling mobile computers by voice, which is also a requirement for wearable computers, has excited the interest of some researchers.In the field of civil engineering there are two interesting reports, one dealing mostly with inspection-oriented applications Garrett, (2000), and other focusing on navigation through drawings Reinhardt and et al. (2000).

Mobile Use at a Construction Site
The new site for the King Faisal University (KFU) campus in Dammam, Saudi Arabia is located on the coast between cities of Dammam and Alkhobar.These two developing cities along with Dhahran city are expected to evolve into a single integrated urban complex that will be the administrative and industrial center of the Eastern Region of Saudi Arabia.The total area of the campus is about 3,000,000 m 2 and will be constructed in several phases.The total building area at the completion of the contract is about 570,000 m 2 .The new campus will accommodate male and female students in two distinct areas.Each area will carry its own educational facilities, public services and housing.
The main campus is divided into five main areas as shown in Fig. 6 while Table 1 shows the subdivision for each area.This division was made in order to acquire an efficient outcome in mobile computing at this construction site.With mobile computing, engineers, architectures, technicians and workmen can take advantage by means of timely and targeted information.The jobs can transmit through a fast medium like wireless devices to a particular engineer or technician, as well as collect data or daily 29 The Journal of Engineering Research Vol. 2, No. 1 (2005)  The Journal of Engineering Research Vol. 2, No. 1 (2005)

Infrastructure and Buildings Site Conditions
The preliminary geotechnical consultant's report (Saudi Services Consultant, 2001) has revealed that the soil is very loose to loose, silty sand up to minimum of 4.0 m depth, followed by dense to very dense, silty sand up to 12 m.The resulting sub-grade shall be compacted by a heavy vibratory roller to a minimum of 70% of the relative density for cohesionless soil or to a minimum of 95% of modified proctor density for cohesive and well-graded soil.The recommended fill by the designer should be placed in layers not exceeding 300 mm each and compacted according to the type of material used.The above information revealed that the soil condition for the site is poor therefore soil treatment is recommended by the consultants.
The scope of the infrastructure and buildings for the site includes but not limited to: To overcome these shortcomings of the site conditions, an approach was suggested to provide mobile communication in order to utilize the flow of information between the client, consultant and the contractor effectively.
The main approach proposed consists of the following tasks: * Exploring the characteristics and potential of commercially available hand held devices for the construction industry, * Evaluating the use of Wifi or blue tooth technology with Palms for data transmissions at the construction project site, * Ensuring flow of information among King Faisal University supervisors, consultants, contractors and the engineers at the construction site, * Providing a document management system for mobile computing, transfer of text, drawings and spreadsheets through the software of latest hand held devices.
The logical flow of the suggested information is shown in Fig. 7, which represents the mobile computing works in construction process at the KFU site.

Conclusions
Construction management can be achieved by using current mobile computing and web services.Their full potential has not been utilized and there are rooms for improvement expected in the future.
The commercially available PDAs already offer abundant functionality and processing speed, however, suitability under stress conditions like dust, strong light, rain, which is normal at a construction site, is another problem which needs to be addressed seriously in the future.There is also the ever-present problem of screen size: either the screen is too small for a good information overview, or too big to fit in a pocket.It is clear that devices not fitting into a foreman's pocket will not be carried around, but rather left back at the site office.
Utilizing the latest in mobile computing at the construction site will provide innovation and customized solutions which would allow individuals in the construction site to maximize the efficiency when collecting data and accessing important information.

Figure 1 .
Figure 1.Base station point to point configuration (C-Spec's Web Site)

Figure 4 .
Figure 4. King Faisal University Construction Site (the foreman's equipment)

Figure 7 .
Figure 7. Logical flow of information suggested at the KFU construction site