School of Civil engineering and Architecture

A concrete pump is a tool used for transferring liquid concrete by pumping. There are five types of concrete pumps. Although no definitive record exists documenting the first use of a concrete pump, the first patent for a concrete pump was established in 1913 in the U.S. Germany became the leading technology innovators in concrete pump development, and used the method extensively for the reconstruction efforts after World War II. West Germany and Japan held the largest Manufacturing companies of concrete pumps throughout the 1980′s and 90′s. Today there are many countries including the U.S. that are participants in the manufacturing of concrete pumps on a mass scale. Many of the largest and most complex construction endeavors since World War II, Would not have been possible without the versatility and extended delivery methods provided by the concrete pump units. Skyscrapers, dams, large bridge pilings, and extended tunnels are poured using concrete pumps. Many types of concrete pumps are used, however typically there are five that are the most widely used in construction that requires concrete pumping operations. The boom pump, placement boom, truckmounted line pump, trailer mounted line pump, skid-mounted line pump. Each of these five types of concrete pumps provide their very own unique method of application depending on the needs of the job.

In the analysis of reinforced concrete (RC) buildings, beam–column joints are regarded as rigid nodes. In fact, joint deformation may make a significant difference in the lateral response of RC buildings if joints are not properly designed and detailed. To consider joint flexibility, several types of joint models have been proposed. However, these models require complicated computations, consequently making them challenging to apply in engineering practice. This paper proposed a simple approach for predicting the contribution of the joint deformation to the total deformation of RC interior beam–column joints under critical structural deformations. To develop such a simple and accurate approach, experimental and analytical studies were performed on RC interior beam–column joints. In this study, eight half-scale joint specimens were tested under reversed cyclic loading, and 39 full–scale FE models were constructed, varying the selected key parameters. The experimental and analytical r...

Currently, the seismic collapse risk of modern code-conforming reinforced concrete (RC) frame structures is often evaluated without considering the behavior of the beam-column (BC) joints since joints designed to meet modern concrete design codes are assumed to be sufficiently rigid. BC joints in RC ductile moment frames may undergo a significant amount of inclined cracking during strong earthquakes. Consequently, the stiffness, strength, and dynamic characteristics of the RC moment frames may vary. Hence, the rigid joint assumption may be unsuitable for assessing the seismic performances of RC ductile moment frames because the local strength and ductility demands of the constituent members can be misinterpreted by structural analyses based on the assumption of a rigid joint. In this study, nonlinear static and dynamic analyses are conducted to quantify the seismic response variations of low- to midrise RC-frame structures under different joint modeling assumptions. In total, six 2D...

KEYWORDS: fly ash, aerated cellular concrete (ACC), thermal insulation material ABSTRACT The Central Energy System in Mongolia consists of five power plants with a total installed capacity of 796 megawatts (MW). Every year for a heating and producing electricity, in the coal fired electric Power Plants in Mongolia, 2.7 million tons of a coal has used and have been producing approximately 531 thousand tons of coal combustion by product per year. These burned coal and coal combustion by product a quantity are increasing year to year. The objective of this study was to determine the possibilities of an effective usage of the coal combustion product of Power Plant III in Ulaanbaator. The investigation is included the determination of a classification of a coal ash which is producing in Mongolia , compared to other countries, the optimal mix proportion to produce aerated cellular concrete (ACC) which is a thermal insulation lightweight concrete with a fly ash. According to laboratory exp...

This study examines the use of concrete waste by-products as a new source of road construction material in Western Australia (WA). The amount of construction waste in Western Australia increases annually, whilst natural rock aggregate is in shortage. This research focuses on whether recycled concrete, derived from various sources such as by-products from the processes of manufacturing ready-mixed concrete and waste from construction and demolition (C&D), is a viable option for use as a base and sub-base course material in road building in WA. A series of laboratory tests were conducted to determine the physical, engineering and performance properties of selected research materials to evaluate their respective potential utilisation. The results demonstrate that the concrete waste materials selected from the companies: Holcim Ltd, All Earth, Capital Demolition and C&D Recycling are suitable for use as base and sub-base layers of flexible pavement in Western Australia.

Барилгын инженер, Архитектурын сургууль /Улаанбаатар хот, Монгол улс/ Хураангуй-Before larger hydraulic structures are built, they should be analyzed in the laboratory as a physical model. A physical model provides the ability to analyze hydraulics parameters in detail, and the hydraulic structure can be assessed. These kinds of experiment and physical modeling have not done been done in Mongolia, because hydraulic structures (category of hydraulic structures I and II) have not been built In Mongolia. In last decade, Mongolian water issue has a big challenge and larger, complex hydraulic structures are planned to be built. To support the sound design and construction of these hydraulic structures we have to develop our research and experiments using physical modeling and any other advanced techniques available.

Before larger hydraulic structures are built, they should be analyzed in the laboratory as a  physical model. A physical model provides the ability to analyze hydraulic parameters in detail, and the hydraulic structure can be assessed. These kinds of experiment and physical modeling have not done been done in Mongolia because hydraulic structures (category of hydraulic structures I and II) have not been built In Mongolia. In last decade, Mongolian water issue has a big challenge and larger, complex hydraulic structures are planned to be  built. To support the sound design and construction of these hydraulic structures we have to develop our research and experiments using physical modeling and any other advanced techniques available. This thesis studied the side-channel spillway of a dam, which was built on the Iven River. I have used a physical and 3D computational fluid dynamics (CFD) model for the study. Using  physical and CFD modeling combines experimental and computational analysis and represent the first time these techniques have been used in Mongolia. The CFD model physics used to evaluate the flow regime in the spillway and free surface was represented with maximum water discharge and velocity profile, streamline, pressure on spillway wall and kinetic energy has defined with CFD model. Results are validated by comparison with results from physical model and CFD model. In addition, this work demonstrates the application of physical and CFD modeling for reservoir spillway design.

Монголын говийн бүсэд уул уурхай, үйлдвэржилтийн хөгжил эрс нэмэгдэн үүнийг даган сууршлын бүсүүд шинээр бий болж хүн амын хүрээгээ тэлсээр байна. Өсөн нэмэгдэх усны хэрэгцээтэй уялдан гадаргын усны нөөц багатай говийн бүсэд он удаан жил тогтсон гүний усыг авч хэрэглэх нь тэр бүр техникийн төгс шийдэл биш гэдгийг эрдэмтэд тэмдэглэсээр байна. Иймд бүс нутаг хооронд ус шилжүүлэн ашиглах хэд хэдэн төслийн нэг болох Орхоны УЦС нь Говийн бүсэд чухал үүрэг гүйцэтгэх ба бүс нутгийн эрчим хүчний асуудал мөн усны дутагдлын асуудлаас гарах боломжийг бий болгоно. Боомт бүхий усан цахилгаан станцын гол судлагдахуун нь усан сангийн ажиллагаа байдаг. Усан сангийн ажиллагаа болон түүний характеристик нь тухайн голын гидрологийн үндсэн параметрүүдээс хамаарна. Энэхүү усан сангийн урьдчилсан судалгааны ажлыг HEC-ResSIM программ ашиглан гүйцэтгэсэн ба загварчлалын үр дүнд усан сангийн үйл ажиллагааны горим, түүний үндсэн характеристик, эрчим хүч үйлдвэрлэх боломж, байгаль орчинд нөлөөлөх байдлыг судалж цаашид хийх судалгааны ажлын чиглэлийг тодорхойлсон болно. Судалгааны дүнд усан сангийн бага эзэлхүүнийг 1128м, ХТТ-ний хэлбэлзэл 1145-1162м, эрчим хүч үйлдвэрлэх дүрмийг усан сангийн дүүргэлтээс хамаарахаар тохируулахад говьд шаардлагатай усны хэмжээг тасралтгүй хангаж /2.27м3/с - ээс 2.8м3/с хүртэл тасралтгүй хангах, 4м3/с хүртэл 2 хоногийн тасралттай өгөх/, багадаа 5МВт, дунджаар 14.35МВт эрчим хүч үйлдвэрлэх, станцын фактор дунджаар 0.41-тэй ашигтай горимд тохирлоо гэж дүгнэж байна.

Project proposal during Interdisciplinary Joint Project seminar in NUT CPD program.
Outcomes of this project will be introduced solution with strategy of new hydropower scheme which would make stable electricity grid system to strengthen Central Energy System. Operation concept of proposed pumped storage power plant is to store excess electricity from CES produced by various power sources such as intermittent renewable source and to produce electricity to CES when it has peak load, therefor system will become more flexible than current condition. Moreover, proposed pumped storage facility will response of safety guarantee for CES.

In this study, flow past square cylinder has been studied with LBM incorporated with Smagorinsky subgrid scale model at wide range of Reynolds number (102-3.82x105). Numerous results from conventional methods like FD and FVM are compared with present study on corresponding condition with in good agreement which imply that our LBM code works properly and has reasonable accuracy. To be stable simulation over long simulation time, control parameters such as input velocity and fluid viscosity or relaxation time should be chosen in a certain combination. In case of channel flow with square obstacle, decrease of input velocity was good combination with increase of relaxation parameter. Our code to simulate flow past bluff bodies can carry out up to Re of 5x105 with some oscillation on vicinity of obstacle edge. In large scale problem with ExLBM would have computational cost which can be managed by exploit of parallel computation. It should be noted that results in paper are shown in dimensionless form.
Standard LBM has not only limited to apply as shown above turbulent flow, but also restricted to non homogenies and multicomponent flows which are challenged and branched to different type LBM models such as Two Fluid and Phase function model etc. Our future work related to both restrictions. With LBM method we have been striving to solve crucial hydraulics problem such as density current in estuary, sediment transport or bed evaluation and ice formation process in continental rivers.

Шинжлэх ухааны ихэнхи салбар тэр дундаа инженерчлэлийн салбарын судалгааны чухал чиглэл бол тооцон бодох ухаан юм. Ус, шингэнтэй холбогдсон инженерчлэлийн салбарт уг ухаан нь тооцон бодох шингэний динамик хэмээн нэрлэгдэж салбарын чухал асуудлуудыг шийдэхэд үнэтэй хувь нэмрээ оруулж байна. Энэхүү илтгэлд харьцангуй шинэвтэр шингэний хөдөлгөөнийг тооцон бодох арга болох Латтис Больцманы аргыг (цаашид ЛБА гэх) сүвэрхэг орчин дундуурх шингэний урсгалд хэрхэн ашиглаж байгаа тухай дурьдах юм.  ЛБА нь бусад уламжлалт тооцон бодох аргуудтай (төгсгөлөг аргууд) харьцуулбал сүвэрхэг орчныг загварчлахад маш тохиромжтойн дээр, хэд хэдэн ялгаатай замаар тооцон бодох боломжийг бүрдүүлж өгч байгаа нь хэмжээсийн янз бүрийн түвшинд газрын доорхи усны хөдөлгөөн, түүнд ууссан бодисын тархалт/дисперси зэргийг загварчлах боломжтойг харуулж байна. Энэ илтгэлийн үр дүнд гарсан тооцооны тохирол болон өмнөх ижил төстэй судалгааны материалуудаас үзэхэд ЛБА нь сүвэрхэг орчин дотуурх урсгалын динамик шинж чанарыг загварчлах өндөр бүтээмжтэй, нарийвчлалтай арга гэдгийг баталж байна.

In this paper, we present numerical procedure for liquid-solid phase change of water with Lattice Boltzmann method (LBM). The numerical procedure is composed as follows. Two distribution functions approach will be used to account flow field and temperature field on fixed grids with 9 directional lattices. The enthalpy-based non iterative method is used for phase change of fluid depending on local enthalpy updates. For open channel fluid flow, free surface formulation of single
phase LBM is employed.

Lattice Boltzmann method (LBM) has been receiving enormous attention from researcher to solve fluid related phenomena. LBM in fluid dynamics simulation, one meet some difficulties, for instance it becomes unstable for high Reynolds number flows and requires computational time and memory for large scale simulations. To avoid this, we used here the Entropic LBM (ELBM) of Karlin's group [7] and implemented parallel code on graphical processing units (GPU). For parallel computation, we used GPGPU system of Nagaoka University of technology, which is equipped with Tesla M2050 processors. To verify accuracy and stability, we have solved double periodic shear layer flow in serial computation. The accuracy and stability of simulation by ELBM were superior to the simulation of standard LBM. Simulations of flow past a circular cylinder is carried out by parallel ELBM, where Reynolds number varies up to 140000. Using the GPU in simulation, computation time speeds up until 10 times faster than that of using central processing units (CPU). The results show that the parallel code of ELBM can solve two-dimensional turbulent flow in arbitrary geometry at the higher stability condition without using any other stabilization techniques. 1. Introduction The simulation of traditional computational fluid dynamics deals with Navier-Stokes equation (NSE). Unlike this, lattice Boltzmann method (LBM) solves the discrete Boltzmann kinetic equation in its simplified form, known as Bhatnagar-Gross-Krook (BGK) equation. Founded in the eighties of last century, LBM become recently a widely used method of computational fluid dynamics (CFD). In LBM, the fluid is simulated by molecular velocity distribution functions with discrete velocities on regular lattice. There are two operations on the distribution functions: streaming and collision. The fluid molecules propagation is described by streaming, which is non-local operation against the local collision operator, describing the collision between molecules [1]. LBM has its intrinsic feature: easy to parallelize on computer [2]. On the other hand, one of long standing problem in fluid flow simulation is the simulation of turbulent flow at high Reynolds number. In CFD, the turbulent flow simulations are usually performed either by computationally expensive direct numerical simulation of NSE or by solving averaged NSE [3, 4, 5, 6]. Direct application of the LBM for the turbulent flow simulation leads to instability of computation, because of the low viscosity of fluid. Laminar flows at low Reynolds number (Re) become turbulent when Re reached the value of Re=300 in the case of flow past a bluff body. One of the promising method of stabilizing the LBM turbulent computation is the entropic LBM (ELBM) of Karlin's group, in which, the distribution functions are straightened to satisfy the maximum condition of the entropy at the every time step of simulation. In this paper, first we confirm accuracy and performance of the ELBM solving double periodic shear layer flow. Then we perform the calculations of high Reynolds number turbulent flow past a circular cylinder using the ELBM of Karlin et al [7, 8] in parallel algorithm.