State of Oklahoma Research Week, March 8, 2013 - Oklahoma City

Oklahoma State University Research Symposium, February 22-24, 2012

Kaos dan waktu luang...

Banyak hal yang orang lakukan untuk mengisi waktu luang. Buat saya, waktu luang biasanya saya gunakan untuk bermain bersama anak (nonton, jalan-jalan), memotret (sebagian hasil2nya bisa dilihat melalui link di tombol navigasi sebelah kanan layar ini), keluyuran bersama anak-istri (silakan dilihat di link facebook saya), atau mendesain kaos. Sayangnya, hobi terakhir ini hanya sebatas iseng atau karena 'dimintai tolong', belum menjadi semacam rintisan bisnis. :) Tulisan ini saya muat dalam blog, supaya seandainya, sekali lagi seandainya ada seseorang yang berminat atau tertarik mengajak saya berbisnis distro kaos atau semacamnya, bisa segera colak-colek saya, hehehehe......
Berikut beberapa hasil iseng tersebut:

 

2012 Conference Papers

ESTIMATING THE ECONOMIC, ENERGY, AND ENVIRONMENTAL IMPACT OF EARTHWORK ACTIVITIES
Michael Phil Lewis, Apif Hajji
Presented in CRC Conference, Purdue University, West Lafayette, Indiana, USA - May 2012
Abstract:
Earthwork activities are a major part of many construction projects. They are typically performed by heavy-duty construction equipment that consumes large quantities of diesel fuel and results in large quantities of CO2 emissions. An estimating tool is needed to accurately assess the economic, energy, and environmental impact of earthwork activities that utilize heavy-duty diesel equipment. This paper presents the framework for a model that can be used to estimate the production rate, unit cost, activity duration, total activity cost, total fuel use, and total CO2 emissions for earthwork activities. Results indicate that there is little difference in the economic, energy, and environmental impact of sand dan gravel, sandy clay and loam, and common earth, but clay has substatially higher impact that other three soil types.


EVALUATION OF CONSTRUCTION EQUIPMENT FLEET PERFORMANCE THROUGH FUEL USE AND EMISSIONS INVENTORIES
Michael Phil Lewis, Apif Hajji
Presented in 9th Asia Pacific Transportation Development Conference & 25th ICTPA Annual Conference, Chongqing, China - July 2012
Abstract:
All types of construction vehicle fleets can benefit from fuel use and emissions inventory evaluation, including publicly-owned fleets that are used for infrastructure construction and maintenance.  Fleet managers can use these types of inventories for minimizing the equipment’s contribution to air pollution and climate change.  For example, identifying and correcting sources of excessive fuel use not only saves money for the fleet owner but also reduces the quantities of harmful pollutants and greenhouse gases that are emitted into the atmosphere.  The purpose of this paper is to evaluate the current status of the construction equipment fleet for the City of Stillwater, Oklahoma by developing and analyzing a fuel use and emissions inventory.  This inventory will be used as a decision support tool to maximize the environmental benefits of their equipment objectives.  This study will seek to answer the following set of research questions:    1) What is the composition of the current fleet?  2) What is the fuel use and emissions inventory for the current fleet?  3) What fuel use and emissions reduction strategies should be considered?  4) What impact would “right-sizing” the equipment fleet have on fuel use and emissions?  It is anticipated that this paper can serve as a case study that can be used by managers of publicly-owned fleets to address their specific concerns related to energy consumption and emissions.


THE DEVELOPMENT AND USE OF EMISSION-BASED INVENTORY FOR CONSTRUCTION EQUIPMENT
(case study: Backhoes Fleet in the City of Stillwater, Oklahoma, USA)
Apif Hajji, Michael Phil Lewis
Presented in 10th International Congress on Advances in Civil Engineering, Ankara, Turkey - October 2012
Abstract:
All vehicles produce pollutant gases that affect the quality of the air. Vehicles in construction industry are typically powered by diesel engines and are considered to be an off-road source of air pollution. Such vehicles are typically transported between sites on a highway via a trailer. Air pollutant emissions from vehicles powered by diesel engines include nitrogen oxides (NOx), particulate matter (PM), hydrocarbons (HC), and carbon monoxide (CO). Any engine that combusts a nonrenewable carbonaceous fuel will have net emissions of carbon dioxide (CO₂). United States Environmental Protection Agency (EPA) estimates that there are approximately 2 million items of construction equipment in the United States (EPA, 2007). It is imperative to reduce pollution from this source to provide healthier environment for construction employees and the public and to reduce overall environmental impact. By reducing pollution, equipment owners are also able to save fuel and money. The purpose of this paper is to: (1) make an emission-based fleet inventory and list the quantities of pollutants emitted for the City of Stillwater, and (2) identify various strategies for the city of Stillwater to reduce emissions from off-road construction vehicles and technologies that the city can employ in the near future.
 
TOWARD DEVELOPMENT OF PRODUCTION-BASED AND COST-BASED GREENHOUSE GAS EMISSION MODEL AND ESTIMATOR FOR EARTHWORK CONSTRUCTION ACTIVITIES
Apif Hajji, Michael Phil Lewis
Presented in Urban Environmental Pollution, Amsterdam, the Netherlands - June 2012
Abstract:
The construction sector produced 6% of total US industrial GHG emissions. The purpose of this paper is to develop an innovative methodology and user friendly emission estimator, particularly for GHG emission or CO₂ released from earthwork construction activity. The estimator will be demonstrated to two types of earthwork activity: bulk excavating with dozer and bulk excavating with scrapers. The estimator will include the production rate of activity, the unit cost of the activity, and CO₂ emission rate of the activity, and modeled by using multiple regression analysis method. Information regarding the production rate and unit cost can be found in RS Means Heavy Construction Data 2011; CO₂ emission rate can be obtained from the EPA’s Inventory of US Green House Gas Emission. Production-based emission model for CO₂  can help construction professionals, an estimator in particular, to forecast the emission footprint of a project based on a quantity takeoff using construction plans and specifications. At the same time, it can help the construction estimator to assign dollar value to construction emissions
 
SENSITIVITY ANALYSIS AND PRODUCTIVITY STUDY OF DIRECTPIPE TECHNOLOGY BY USING SIMULATION
Apif Hajji
Presented in 2nd International Conference on Rehabilitation and Maintenance in Civil Eng., Sebelas Maret University, Surakarta, Indonesia - March 2012
Abstract:
Many techniques of trenchless technologies have been evolved over time to install, maintain, and manage underground infrastructure system, but all of these fail to satisfy implementer due to complex implementation process, economy, and adaptability to different geological conditions. Directpipe technology is one of new technology that has been invented by German’s Herrenknecht Inc. recently. It claims that the technology is economical, fast, and has a single step installation procedure. The objective of this paper is to analyze and evaluate that claim by using CYCLONE model simulation. The simulation is used to compare the Directpipe technology with traditional trenchless technology by incorporating real costs and duration into the model. Sensitivity analysis is carried out to find out a suitable combination of resources delivering utmost productivity.

Alif and Fire Truck

Pagi itu, Rabu 16 Nopember 2011, jam 8 tepat, sebuah truk pemadam kebakaran lengkap dengan tiga personelnya datang ke apartemen kami....bukan, bukan hendak memadamkan api, tapi untuk menjemput Alif dan mengantarkannya ke sekolah.

Lho ada apa?

Ya, Alif mendapat kehormatan dijemput oleh sebuah fire truck karena dia baru saja menjadi pemenang lomba poster bertema: Protect Your Family from Fire. Sebuah acara yang diadakan City of Stillwater: Fire Protection Week. Lomba tersebut diikuti siswa-siswa elementary school di Stillwater, Oklahoma dalam rangka menanamkan kesadaran dan pengertian anak-anak tentang tata cara dan prosedur penyelamatan dan penanggulanagan bahaya kebakaran. Suatu pengetahuan yang tentu saja tidak pernah terpikirkan di negara kita untuk diberikan pada anak usia sekolah dasar.

Yang menarik dari poster Alif (dan mungkin ini yang menyebabkannya jadi pemenang) adalah bagaimana dia menunjukkan tindakan yang perlu dilakukan orang pada saat asap pekat mulai memenuhi suatu ruangan. Gambar beberapa orang merangkak (di bawah level asap), tanda penunjuk keluar (exit) yang menyala terang, dan denah jalur evakuasi. Persis seperti materi 'Pengamanan Bahaya Kebakaran' yang saya berikan di matakuliah Utilitas di kampus saya. Bedanya, ini untuk anak SD!!

'Musibah', itu istilah yang sering kita gunakan ketika bencana semacam kebakaran terjadi pada bangunan. Sementara bagaimana kita bertindak ketika kebakaran terjadi, hanya segelintir saja yang mengetahui, bahkan orang dewasa sekalipun. Di negara lain, kata 'musibah' mungkin tidak dikenal, tapi mereka lebih tahu tentang ikhtiar memberikan pengetahuan tentang kebakaran pada anak-anak.

Environmental-Economic-Energy Efficient Earthwork Emissions Estimator (E-7 ver.1.0, 2011)

This is the first version of emission calculator for earthwork construction activities.
The emission here is mainly released by heavy construction equipment used in this type of activities. The estimated emission footprint will be based on productivity emission rates and cost emission rates. Productivity emission rates are emission rates based on units of production, such as grams of pollutant emitted per cubic-yard of excavation (gr/cy). Cost emission rates are emission rates based on the construction cost, such as grams of pollutant per dollar construction cost (gr/$).
The user interface input page is developed by Visual Basic for Excel spreadsheet, while the core model is formulated by using multiple regression analysis.
This first version of calculator will only focus on one sub-set of earthwork activities: Excavation and Fill, and only calculate the green house gas (GHG) or CO2 emission.

Construction Simulation with Cyclone

Applications of simulation on tunneling operations have been previously In 1973, Halpin developed the CYCLONE _cyclic operation network_ format that has become the basis for a number of construction simulation systems. CYCLONE allowed the user to build models using a set of abstract but simple parameters. This system was the basis for a wide range of construction simulation research efforts including tunneling and microtunneling. In 1978, Halpin popularized the use of CYCLONE format with MicroCYCLONE program. MicroCYCLONE is a microcomputer based simulation program designed specially for modeling and analyzing site level processes which are cyclic in nature. Due to the accessibility and ease of use, a Web-based version of MicroCYCLONE, namely, WebCYCLONE maintained by Purdue University is used in this research to perform simulations (Division of Construction Engineering and Management Website 2005).

The CYCLONE methodology is a modeling technique that allows the graphical representation and simulation of discrete systems that deals with deterministic or stochastic variables. Using the CYCLONE methodology for simulation of construction operations, construction processes are divided into discrete pieces or work tasks and their interactions are represented. This type of simulation focuses on resources and their interactions and presents a graphical representation of their interactions.

The basic modeling elements used in the CYCLONE methodology are as follows. These elements are described as follows: combi _COMBI_, represents a work task constrained by one or more resources; counter _COU_, keeps track of the number of

times a unit passes it; function _FUN_, simulation entities can be accumulated at this node; normal _NORMAL_, represents a nonconstraint work task with an infinite number of servers; queue _QUE_, a node where idle resources wait and is always followed

by COMBI nodes; Arc, indicates the logical structure of model and direction of entity flow _Halpin and Riggs 1992_. Resources can be in one of two states—active _denoted by a square element_ or idle _represented by a circle element_. Resources will move between these two states, as they “traverse” from one activity to another. A flow unit traverses a CYCLONE network with the following effects:

• Waits in QUEUE nodes for processing;

• Initiates _or signal_ the processing of a work task;

• Generate other entities where they traverse a QUEUE-GEN node;

• Get consolidated with other flow units when they pass a

CONSOLIDATE Function; and

• Register productions where they pass a function COUNTER

 

Some Examples:

Study of Herrenknecht's DirectPipe Technology and Cyclone Model Simulation

Various methods for crossing works have so far been applied in order to build steel pipelines. Pipe Jacking and Segmental Lining allow for the construction of concrete protective tunnels with subsequent insertion of the product pipeline. The HDD method, indeed, allows the laying of a steel pipeline but includes the construction of a pilot bore and several hole opening steps prior to pipe pull-in. Recent developments such as the Easy Pipe method comprise jacking processes where tight connection interim steel pipes are pushed towards the target shaft, coupled to a pipeline and then can be pulled back together in a second step. All these methods include a two- or multi-step pipe installation process.

(courtesy of Herrenknecht AG., Germany)

The development of the DIRECT PIPE method, which is a combination of Micro-tunneling and HDD, was not only based on the creation of a one-step pipe laying method but also on the provision of an efficient alternative to existing methods, which is able to minimize the geological risks (e.g. drill-hole collapse using HDD). With Direct Pipe steel pipelines can now for the first time be jacked efficiently and fast in one operation process. The direct installation of the pipeline allows for continuous drill-hole support preventing borehole collapse. (Figure 1).

The Direct Pipe machine is mounted in front of the pipeline and is welded onto it (Figure 2). The Pipe Thruster, which is located in the launch pit, operates as thrust unit - clamping the pipeline on the outside and pushing the machine as well as the pipeline into the ground (Figure 3). The tunnel face is excavated by the Direct Pipe machine similar to the pipe-jacking method, which has been established for several decades. The cutting wheel can be equipped with cutting tools adapted to the specific geological conditions. In contrast to HDD technology, larger boulders, hard rock as well as soft, unstable soils (gravel) can be crossed. The excavated material is removed via a slurry circuit with separation plant in order to separate the spoil from the slurry liquid before feed pumps transport the liquid back to the tunnel face.



The Direct Pipe machine is controlled from the operating container. A gyro compass and a hydrostatic water leveling system are used for the horizontal and vertical machine surveying. To facilitate the controlled steering of the machine (and therewith the connected pipeline), the Direct Pipe machine is longer than an ordinary micro-tunneling machine (approximately 12 meters instead of 6 meters). At the end of the Direct Pipe machine a lubrication ring is mounted in the transition area between and the product pipeline, where most of the bentonite is added in the annular gap, in order to reduce the friction between the pipeline and the ground to a minimum.

Table 1. QUEUE elements in DirectPipe model

Element number	Description	Generate	Quantity	Resource Type
1	Pipes in site storage	-	12	Pipes
4	Needs connector	-	-	-
7	Crew A idle	-	6	Crew A
8	Needs check connection	-	-	-
10	Connection ready	4	1	Connection
11	Position occupied	-	-	-
12	Position available	-	1	Position
15	Pipe section ready to thruster	-	-	-
17	Pipe section ready to installation	-	-	-
19	Crew B idle	-	4	Crew B
21	Crane idle	-	3	Crane
25	Needs lubricants	-	-	-
27	Bentonite ready	-	1	Bentonite
28	Lubricants ready	4	1	Lubricants
30	Spoil tank full	-	-	-
32	Backhoe ready	-	1	Backhoe
33	Truck ready	-	1	Truck
34	Spoil tank not full	4	1	Spoil tank
35	Pipes in distance	-	-	-
37	Control room to command	-	1	Remote control room
38	Thruster ready	-	1	Thruster
40	Slurry needs recycle	-	-	-
42	Water ready	4	1	Water
43	Cable and hose ready	-	1	Cable and hose

Table 2. COMBI elements in DirectPipe model

Element number	Description
2	Bring pipes to connecting
5	Connect / weld pipes
9	Check pipes connection/welding
13	Attach pipes to crane
16	Roll pipes to thruster machine
18	Pipes setup/installation
26	Mix lubricants
31	Empty spoil tank
36	Uninstall cable/hose/UNS
41	Recycle slurry



Table 5. Duration used in Simulation

Element number	Description	Distribution
2	Bring pipes to connecting	TRI (2, 5, 15)
5	Connect / weld pipes	UNI (10, 15)
9	Check pipes connection/welding	UNI (10, 15)
13	Attach pipes to crane	DET (2)
16	Roll pipes to thruster machine	UNI (1, 2)
18	Pipes setup/installation	BETA (28, 80, 0.761, 1.841)
26	Mix lubricants	TRI (25, 30, 35)
31	Empty spoil tank	TRI (20, 30, 35)
36	Uninstall cable/hose/UNS	BETA (7, 33, 0.643, 3.020)
41	Recycle slurry	TRI (10, 12, 15)
6	Dummy	DET (0)
14	Lift to guard rail	DET (1)
20	Crane returns	DET (2)
23	Thrust pipes	DET (40)

Table 6. Resource cost information

Resource	Costs ($)
Pipes	5600/section
Crew A	44/hr
Crew B	40.8/hr
Crane (+ operator)	61.45/hr
Thruster system	550/hr
Backhoe (+ operator)	27.9/hr
Truck	51/hr
Water	17
Bentonite	21.6
Lubricants	28

Simulation Result

A total of 12 cycles simulation were performed with the Cyclone model. The result of productivity per time unit is 0.1894977 for total simulation of 1266.5 time unit. It gives the productivity rate of 0.208 meter/minute or 12.48 meter/hour.

Considering the cost of resources, the achieved productivity rate takes US$ 5,706/meter.