Wei Victor Liu

University of Alberta | UAlberta · Department of Civil and Environmental Engineering and the School of Mining and Petroleum Engineering

The objective of this study is to propose an analytical solution that can predict the temperatures of dumbbell-shaped rubber specimens under cyclic deformation. Initially, a new mathematical equation was formulated by modifying the Mooney–Rivlin strain energy function, using the pseudo-elasticity theory and the inverse analysis method. This equatio...

The aim of this study is to appraise the potential of calcium sulfoaluminate (CSA) cement-based grouts in simulated permafrost environments. The hydration and performance of CSA cement-based grouts cured in cold environments (10, 0, and −10 °C) are investigated using a combination of tests, including temperature recording, X-ray diffraction (XRD) t...

This study appraised the feasibility of recycled carbon black (RCB) derived from scrapped off-the-road (OTR) tires, denoted as RCB-OTR, as aggregates to develop thermal insulation mortars. Sand in Ordinary Portland cement (OPC)-based mortars was replaced by RCB-OTR in volumetric proportions of 0, 30, 60, and 100%. The results revealed that the deve...

The objective of this study is to investigate the effects of site operating conditions on the real site TKPH (tonne-kilometer-per-hour) of ultra-large off-the-road (OTR) tires. To achieve this, a novel finite element OTR tire thermal (OTRTire-T) model was developed to predict the temperatures of OTR tires. As per the results from the OTRTire-T mode...

The truck haulage data from open-pit mine sites are usually massive and multidimensional with multi-peak Gaussian distributions. Artificial neural networks (ANNs) are well-known machine learning algorithms to handle massive and multidimensional data for building models. Moreover, Gaussian mixture modeling (GMM) is a suitable option for processing t...

The unconfined compressive strength (UCS) of alkali-activated slag (AAS)-based cemented paste backfill (CPB) is influenced by multiple design parameters. However, the experimental methods are limited to understanding the relationships between a single design parameter and the UCS, independently of each other. Although machine learning (ML) methods...

The historical datasets at operating mine sites are usually large. Directly applying large datasets to build prediction models may lead to inaccurate results. To overcome the real-world challenges, this study aimed to handle these large datasets using Gaussian mixture modelling (GMM) for developing a novel and accurate prediction model of truck pro...

About 50% of Canada’s landmass is classified as permafrost regions. In permafrost regions, conventional grouts made of ordinary Portland cement (OPC) may cause the failure of grouting because of their slow strength development at cold temperatures. Compared to OPC, calcium sulfoaluminate (CSA) cement exhibits the characteristics of rapid setting an...

About 50% of land mass of Canada is covered with permafrost. In these permafrost regions, a large amount of valuable mineral deposits are located. To mine in these permafrost regions, cement-based mixtures (e.g., concrete, shotcrete, backfill, and grout) are expected to be widely used for rock support and infrastructure construction. However, cold...

The mining industry is the largest contributor to the economy of Northwest Territories, accounting for about 25% of the territorial GDP in 2021. During mining operations, cement-based materials (e.g., concrete, shotcrete, backfill, and grout) are essential parts of rock support and infrastructure construction. Currently, all the cement consumed in...

In the past decade, machine learning (ML) algorithms have been widely applied to build prediction models for various mining applications. However, no research has been reported that forecasts truck productivity using ML algorithms. In this study, two tree-based ensemble learning algorithms, including random forest (RF) and gradient boosting regress...

Increasing the use of low carbon footprint calcium sulfoaluminate belite (CSAB) cement is a potential way to reduce carbon dioxide emissions related to the cement and concrete industry. However, rapid setting is one of the barriers limiting the large-scale applications of CSAB cement. To address this issue, experimental studies were carried out to...

The objective of this study is to conduct a numerical investigation to examine the temperatures in off-the-road (OTR) tires under operating conditions at mine sites. To achieve this, a new mathematical equation was developed based on a modified Mooney-Rivlin (MR) strain energy function, the pseudo-elasticity theory, and the inverse analysis method....

Belitic calcium sulfoaluminate (BCSA) cement-based mixtures are suitable for permafrost region applications due to their fast strength development. To better understand their performance and guide future applications, this study aimed to develop a numerical model for predicting the temperature profiles in BCSA cement-based mixtures used in permafro...

The objective of this study was to develop a novel phenomenological model that can predict the hysteresis loss of rubber compounds obtained from ultra-large off-the-road (OTR) tires under typical operating conditions at mine sites. To achieve this, first, cyclic tensile tests were conducted on tire tread compounds to derive the experimental results...

This study extended blending proportion range of ordinary Portland cement (OPC) and calcium sulfoaluminate (CSA) cement blends, and investigated effects of proportions on setting time, workability, and strength development of OPC-CSA blend-based mixtures. Thermogravimetric analysis (TGA) and X-ray diffraction (XRD) were conducted to help understand...

Burning natural gas to heat water for oil sands separation is and energy and carbon-intensive process. This study presents a COMSOL Multiphysics simulation model that comprehensively investigates the feasibility of utilizing geothermal energy from enhanced geothermal systems (EGSs) as a heat source for oil sands separation. The simulation model was...

Microbially induced corrosion (MIC) is a serious issue for sewer structures worldwide. Many studies have been carried out to develop more durable cement-based materials under the MIC attack. Due to a lack of a standard, various methods have been tried in the evaluation of resistance of different cement-based materials against MIC. A review of exist...

Fast setting is an important reason restricting the applications of eco-friendly calcium sulfoaluminate belite (CSAB) cement. To help spread the application of CSAB cement, this study investigated the influence of sodium gluconate (SG) as a setting retarder on the setting, workability, and strength development of CSAB cement mixtures. Quantitative...

The objective of this study is to investigate the hysteresis loss of ultra-large off-the-road (OTR) tire rubber compounds based on typical operating conditions at mine sites. Cyclic tensile tests were conducted on tread and sidewall compounds at six strain levels ranging from 10% to 100%, eight strain rates from 10% to 500% s ⁻¹ and 14 rubber tempe...

This study aims to develop a simulation model to investigate the feasibility of extracting geothermal energy from abandoned petroleum wells using doublet deep borehole heat exchangers (DBHEs) in the Western Canadian Sedimentary Basin near Hinton. A three-dimensional simulation model that simplifies heat convection to one dimension was built and ver...

Reducing the thermal conductivity of cement-based building materials can alleviate the energy consumption and carbon dioxide (CO2) emissions that are related to space heating in buildings. The objective of this study is to incorporate expanded perlite into calcium sulfoaluminate (CSA) cement-based mortars to develop a novel building material that h...

This study aims at improving the acid resistance of metakaolin-based geopolymer by substituting metakaolin with calcium aluminate cement. Calcium aluminate cement was added at weight ratios of 5% and 10%. The raw materials were activated with a mixture of NaOH solution and Na2SiO3 solution. The cured geopolymer mortars were immersed in a sulfuric a...

The prediction of ground temperature is often necessary for the design and simulation of a borehole heat exchanger (BHE) system in its service life (which usually spans decades). A moving finite line source solution (MFLSD) calculates the ground temperature while considering the buried depth and groundwater flow for a single borehole. However, a BH...

Immersion test is time-consuming and labor-intensive in evaluating the resistance of concrete against sulfuric acid attack. An alternative way for acid resistance evaluation is to predict the sample deterioration through machine learning methods using a currently available database. However, current predictive models have failed to include testing...

This study aims to understand the effects of property variations on prediction discrepancies in the output capacity (i.e., output power) of deep coaxial borehole heat exchangers under different operational conditions. These properties include the specific heat and thermal conductivity of the water and the reservoir rock, as well as the density and...

This study aims to evaluate the performance of silica fume (SF) and nano-silica (NS) on enhancing the sulfuric acid resistance of mortar mixtures. The NS and SF were added as substitutions for cement at various dosages. The cured samples were immersed in the sulfuric acid solution with a pH of 2 for 75 d. A compressive strength test and absorption...

This study aims to explore the possibility of using calcium sulfoaluminate (CSA) cement to prevent early-age frost damage. CSA-based and ordinary Portland cement (OPC)-based mortars with and without calcium nitrate were exposed to −10 °C for 3 days, then re-cured at 23 °C until 28 days. Another group of mortars was directly cured at 23 °C as refere...

Acid mine drainage has been an important threat to cementitious structures. To improve the acid resistance of cementitious composites used under acid mine drainage attack, this study is aimed at investigating the effect of cellulose nanocrystals (CNCs) on the acid resistance of cementitious composites. CNCs were added to the mortar mixtures as addi...

It is important to understand the behaviour of voussoir beams in the design of underground excavations. There are a large number of discrepancies between the results obtained by different researchers so far. To resolve these discrepancies, physically testing the stress distribution at the midspan and abutment of voussoir beam is the key. In this pa...

The objectives of this study are to utilize and investigate the performance of molasses as a retarder and plasticizer for calcium sulfoaluminate (CSA) cement and examine the effects of molasses on the hydration reaction, microstructure, and mechanical properties of CSA cement mortar. In this study, experiments were conducted to measure the setting...

The currently available moving finite line source (MFLS) model for design and simulation of vertical borehole heat exchangers (BHEs) neglects the effect of buried depth, i.e., the vertical distance between the ground surface and the BHEs. We propose a new analytical solution of the MFLS model with the buried depth added in a single integral form—it...

The objective of this paper is to investigate the effects of initial particle gradation and rock content on the crushing behavior (i.e. grain size before and after crushing) of weathered phyllite fills. Compaction tests were conducted on weathered phyllite fills with rock contents of 35%, 45%, 55%, 65% and 75% (by weight). First, the particle size...

Deep petroleum wells are often associated with high bottom-hole temperatures and can provide a cost-effective way to produce geothermal energy. The goal of this study is to develop a reliable simulation model to demonstrate the feasibility of extracting geothermal energy with deep coaxial borehole heat exchangers in abandoned petroleum wells in the...

Coal dust is one of the most serious hazards on mine sites. Water spray with surfactant added is an effective way to control the coal dust. In this study, wind tunnel experiments were designed to evaluate the surfactant on coal dust suppression efficiency. A CFD modeling was first constructed in to investigate the coal dust particles movement chara...

One of the most serious mining disasters in underground mines is rockburst phenomena. They can lead to injuries and even fatalities as well as damage to underground openings and mining equipment. This has forced many researchers to investigate alternative methods to predict the potential for rockburst occurrence. However, due to the highly complex...

Foam is an effective material for controlling industrial dust. To optimize and upgrade the performance of dust-suppression foam, this paper proposes a method of exposing the foaming agent solution to a magnetic field of specific intensity prior to foaming. The effects of magnetization on foaming capacity, foam stability and foam size were investiga...

The utilization of polymer stabilizers is a promising method in mitigating bauxite residue (red sand) dust pollution. Its thickening property can effectively bind sand particles by constructing crusts to withstand wind erosion. Previous studies recommended the mixture of polymer solutions for a better dust control performance. However, limited refe...

High production rates and low operating costs highlight block caving as one of the favorable underground mining methods. However, the uncertainties involved in the material flow make it complicated to optimize the production schedule for such operations. In this paper, a stochastic mixed integer linear optimization model is proposed in order to cap...

This study aims to investigate the use of pozzolans–fly ash (FA), metakaolin (MK), and silica fume (SF)—which can be sourced from local mine waste to improve acid resistance of rehabilitation shotcrete. Cement was replaced with these pozzolanic materials at ratios of 5%, 10%, 20%, and 30% to prepare cylindrical samples. These samples were immersed...

The selection of an elevation for the placement of the undercut level is a decisive initial step in the planning and design of block caving mines. It is key for the success of a caving project to define the undercut elevation that will most likely yield the highest possible net present value (NPV) of the operation, considering the discounting perio...

This paper is intended to conduct a narrative review on the acid corrosion of sewer tunnel concrete in the City of Edmonton-an investigation on the MIC (microbially induced corrosion) mechanism and the potential control methods to improve the sustainability of concrete. Firstly, three categories of main influencing factors were identified for the r...

The mining industry often uses shotcrete for ground stabilization. However, cracking within shotcrete is commonly observed, which delays production schedules and increases maintenance costs. A possible crack reduction method is using expansive shotcrete mixture consisting of calcium sulfoaluminate cement (CSA), ordinary Portland cement (OPC), and c...

The mining industry often uses shotcrete for ground stabilization. However, cracking within shotcrete is commonly observed, which delays production schedules and increases maintenance costs. A possible crack reduction method is using expansive shotcrete mixture consisting of calcium sulfoaluminate cement (CSA), ordinary Portland cement (OPC), and c...

This study established numerical modeling using COMSOL™ to examine the influence of horizontal location and drainage ability of surface borehole on spontaneous combustion in longwall working face gob. Rescaled Range Analysis (R/S analysis) was employed to investigate the chaos characteristic of N2/O2 ratio from a surface borehole in 10416 working f...

The objective of this study is to investigate the role of different atmospheric temperature on the effectiveness of chemical suppressants to control mine haul road dust. In this study, water and selected chemical surfactants-salt, chloride free agents, polymers, and molasses-were tested experimentally for their dust retention efficiency under three...

The current trend of deeper and lower-grade deposits makes open pit mining less profitable. Mass mining alternatives have to be developed if mining at a similar rate is to be continued. Block cave mining is becoming an increasingly popular mass mining method, especially for large copper deposits currently being mined with open pit methods. After fi...

Predicting the stability of open stopes can be a challenging task for underground mine engineers. For decades, the stability graph method has been used as the first step of open stope design around the world. However, there are some shortcomings with this method. For instance, the stability graph method does not account for the relaxation zones aro...

Microbially induced corrosion (MIC) is occurring throughout concrete sanitary tunnels in Edmonton. It is reported that up to 20% of sanitary sewer pipes are in poor condition. The City of Edmonton (COE) is seeking possible methods to control the corrosion. To that end, a joint Sustainability Scholars Program was initiated between the COE and the Un...

A large-scale wildfire had broken out at Fort McMurray in Alberta, Canada during May 2016. Many oil sands mining activities were affected due to the wildfire and the associated ash emissions. In particular, ash emission generated from the fire outbreak is a huge problem during the post-fire cleanup. These emissions pose a severe health hazard to wo...

Fast drainage is a key in balancing coal bed methane (CBM) control and coal fire prevention in highly gassy and spontaneous combustion-prone longwall faces in the initial mining range. In this case study, two similar working faces, the 15202 and 15203 faces of Shigang Mine, were studied for the CBM emission history and its control strategy in the i...

Purpose The trapped geothermal heat in the infinite rock mass through which mine tunnels are excavated is a great threat to the safety of personnel and mine operating equipment in deep underground hot mines. In order to lessen the temperature inside the tunnel a considerable amount of energy is being spent by the way of using ventilation and coolin...

The heat flow generated from the infinite rock mass surrounding the underground tunnels is a major cause for the increasing cooling demands in deep mine tunnels. Insulation layers with lower thermal conductivities on tunnel walls and roof ceilings are believed to supply a thermo-barrier for heat abatement. However, it is found that no systematic th...

This paper describes the thermal properties of lightweight dry-mix shotcrete using expanded perlite aggregate (EPA). Mixes made with different EPA/sand ratios were sprayed through the dry-mix shotcreting technique onto wooden molds to produce panels for mechanical and thermal testing. The density, uniaxial compressive strength (UCS), splitting tens...

http://www.mvlwb.ca/Boards/WLWB/Registry/2012/W2012L2-0001/W2012L2-0001%20-%20Ekati%20-%20WROMP%20-%20Version%204.1%20-%20May%205_14.pdf

As the demand for minerals increases over the world, mining reaches new depths. As a result, one has to contend with increasing temperatures in working areas due to geothermal heat trapped in the surrounding rocks. One consequence of this is an escalating cost related to ventilation and cooling systems in order to keep the working environment comfo...

This paper describes the thermal properties of lightweight dry-mix shotcrete using expanded perlite aggregate (EPA). Mixes made with different EPA/sand ratios were sprayed through the dry-mix shotcreting technique onto wooden molds to produce panels for mechanical and thermal testing. The density, uniaxial compressive strength (UCS), splitting tens...

This paper aims to investigate the use of expanded perlite in mortar, for further application of shotcrete to thermal insulation of underground mines. Mixes were designed according to the typical proportions of underground shotcrete, with the sand volumetrically substituted by expanded perlite. Tests of samples were conducted at four ages. Transien...