A finite-element approach is used to analyze the slope stability problem and to examine the effect of soil dilatancy on the stability of slopes. It is found that soil dilatancy has a significant ...effect on the stability of slopes, and that higher values of dilation angle lead to larger stability numbers. Therefore, the stability numbers obtained from limit analyses (lower upper bound solutions) are not conservative for granular soils that exhibit a dilation angle smaller than a soil's friction angle.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Damage due to wind-related disasters is increasing due to global climate change. Many studies have been conducted to study the wind effect surrounding low-rise building using wind tunnel tests or ...numerical simulations. The use of numerical simulation is relatively cheap but requires very good command in handling the software, acquiring the correct input parameters and obtaining the optimum grid or mesh. However, before a study can be conducted, a grid sensitivity test must be conducted to get a suitable cell number for the final to ensure an accurate result with lesser computing time. This study demonstrates the numerical procedures for conducting a grid sensitivity analysis using five models with different grid schemes. The pressure coefficients (CP) were observed along the wall and roof profile and compared between the models. The results showed that medium grid scheme can be used and able to produce high accuracy results compared to finer grid scheme as the difference in terms of the CP values was found to be insignificant.
•The production of green sustainable concrete utilising ultrafine palm oil fuel ash (UPOFA) and waste plastic Polyethylene Terephthalate (PET) fibres was presented in this study.•The proportions of ...UPOFA were (20% and 40%) as a partial replacement of the total cement binder combined with 1% PET fibres.•The combination of UPOFA and PET fibres enhanced strength and transport properties of Ultra-High-Performance PET Green Concrete (UHPPGC).
The production of green sustainable concrete with enhanced performance against severe environmental conditions by using recycle waste materials has been a primary concern for recent studies. This article reports a study on investigating the effect of incorporating ultra-fine palm oil fuel ash (UPOFA) with shredded recycled waste bottle in form of Polyethylene Terephthalate (PET) on the engineering and transport properties of ultra-high-performance concrete. UPOFA was used as a partial replacement binder in varied proportions (20% and 40%) of the total cement binder, whereas shredded recycled PET bottles were added as reinforced fibre by 1% of the total mix volume. The greatest compressive strength was registered by a combination of 20% UPOFA and PET fibre in U20-UHPPGC. The combination of 40% UPOFA and PET fibres in U40-UHPPGC mix demonstrated a superior enhancement in terms of transport properties at the age of 28 days, such as porosity, initial surface absorption, gas permeability, water permeability and rapid chloride permeability. Thus, pozzolanic UPOFA can improve the engineering and transport properties of ultra-high-strength concrete. The overall results indicated that the PET fibre reinforced with UPOFA can produce UHPPGC with promising improvements in engineering and transport properties. The incorporation of waste materials into concrete constructions can reduce cement consumption and prevent the environmental pollution with save energy at the same time.
Single-storey houses are classified as low rise building and vulnerable to damages under windstorm event. This study was carried out with the aim to investigate the pressure distribution and ...streamlines around an isolated house by considering the effect of terrain characteristics. The topographic features such as flat, depression, ridge, and valley, are considered in this study. This simulation were analysed with Ansys FLUENT 14.0 software package. The result showed the topography characteristics influence the value of pressure coefficient and streamlines especially when the house was located at ridge terrain. The findings strongly suggested that wind analysis should include all topographic features in the analysis in order to establish the true wind force exerted on any structure.
Rural house classified as a low-rise non-engineered building and it is vulnerable to damages during a windstorm event. Many studies have proven that the roof of a low-rise house is especially ...susceptible to damage and this phenomenon worsens for the case of rural house. This paper aims to investigate the change in distribution of pressure coefficient and streamlines pattern surrounding an isolated rural house by varying the wind directions. The analysis was conducted using Computational Fluid Dynamics method embedded in ANSYS FLUENT software package. The results showed that in most cases, the roof ridge exhibited the highest suction. The maximum suction was observed for Model A2 (30° from the normal to the major face of the kitchen house).
Most of the rural houses in Malaysia are classified as non-engineered building. These rural houses are characterized by having overhang roof and kitchen house. There have been many cases of such ...houses being damaged during thunderstorm events. This study investigates the changes in the air flow characteristics due to the presence of a kitchen house. The roof pitch of core house, overhang and gap height were maintained at 27°, 0.5 m and 0.5 m, respectively. Computational Fluid Dynamics (CFD) simulations based on Reynolds-averaged Navier-Stokes equations (RANS) was used together with turbulence model, RNG k-ε. The results showed that the presence of a kitchen house slightly increased the suction on the roof ridge but significantly changed the flow pattern in the windward direction.
This paper summarizes results from a static pushover analysis on the inelastic response of bridge columns supported on pile groups and consisting of full moment connection cast-in-place steel shell ...piles. The analytical models considered the nonlinear actions that develop in the column, the supporting piles and the soil. Parametric studies were then carried out under different sets of column height to diameter or aspect ratios and soil-structure interaction, and included variations in: (a) nonlinear soil-structure horizontal interaction and (b) nonlinear soil-structure vertical interaction. Parametric studies confirmed that variations in the horizontal and vertical soil stiffness can affect the pile cap lateral deflection and rotation, respectively. As importantly, results from this analysis indicate that for columns with aspect ratios lower than six, the contribution of soil-structure interaction is significant; however, for columns with higher aspect ratios and for stiffer soils, the effects of soil-structure interaction are almost negligible regarding the lateral response of the system. Detailed results from this study are presented and discussed in this paper.
Rural houses are classified as low rise and non-engineered building. These types of structures are at risk of getting damage during a windstorm event. Many studies have been conducted to investigate ...the air flow characteristic using CFD for structures located on flat terrain. However, wind that passes a ridge terrain has stronger wind speed and can be a potential hazard to rural houses located on top of it. This study investigates the air flow characteristics along the 2-D profile of a rural house model located on top of a ridge terrain considering the effect of varying the terrain height. Computational Fluid Dynamics method was used with the aid of ANSYS FLUENT software package. The results presented in this study are in term of pressure coefficient both with positive and negative values. The flow patterns over the models are observed using streamline. The result showed the ridge terrain height influenced the pressure coefficient and flow pattern. The highest suction was observed for the steepest ridge terrain due to the build-up in the local up-slope wind acceleration.
The aim of this study is to enhance the validation of CFD exercise along the roof profile of a low-rise building. An isolated gabled-roof house having 26.6° roof pitch was simulated to obtain the ...pressure coefficient around the house. Validation of CFD analysis with experimental data requires many input parameters. This study performed CFD simulation based on the data from a previous study. Where the input parameters were not clearly stated, new input parameters were established from the open literatures. The numerical simulations were performed in FLUENT 14.0 by applying the Computational Fluid Dynamics (CFD) approach based on steady RANS equation together with RNG k-ϵ model. Hence, the result from CFD was analysed by using quantitative test (statistical analysis) and compared with CFD results from the previous study. The statistical analysis results from ANOVA test and error measure showed that the CFD results from the current study produced good agreement and exhibited the closest error compared to the previous study. All the input data used in this study can be extended to other types of CFD simulation involving wind flow over an isolated single storey house.
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