GROUND IMPROVEMENT AS ALTERNATIVE TO PILING – EFFECTIVE DESIGN SOLUTIONS FOR HEAVILY LOADED STRUCTURES

Well-designed ground improvement options without compromising on stringent design criteria may effectively replace conventional foundation solutions for a wide range of applications involving heavy loads and structures sensitive to settlement. Case studies illustrate the application of different ground improvement methods used in different projects and soil conditions by adopting of advanced design considerations to achieve optimal solutions for the project and customer benefit. Beneficial returns in terms of lowering construction costs and shortening construction time with consistency in quality are discussed where applicable in relation to the required capabilities and experiences of an organisation to deliver the alternatives. Opportunity management gives the chance to achieve the project scopes for the client by optimizing cost, time and quality and recommendations are summarised to foster the chance to identify optimal geotechnical solutions.

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Study on the Behavior of Geosynthetic-Reinforced Pile-Supported Embankments in Soft Ground Improvement Solutions

Journal of Southwest Jiaotong University ◽

10.35741/issn.0258-2724.55.5.23 ◽

2020 ◽

Vol 55 (5) ◽

Author(s):

Nguyen Tuan Phuong ◽

Nguyen Anh Tuan

Keyword(s):

Load Transfer ◽

Ground Improvement ◽

Soft Soil ◽

Soil Conditions ◽

Soft Ground ◽

Construction Time ◽

Pile Cap ◽

Pile Caps ◽

Improvement Method ◽

Foundation Type

Embankments on soft ground often encounter many problems such as settlement, slip, and deformation that exceed the permitted limit. In recent years, a new type of foundation called "geosynthetic-reinforced pile-supported embankments" has been used. Until now, although the behavior of this foundation type has been analyzed and certain results have been presented in literature, calculation methods do not allow geotechnical engineers to calculate the results accurately. This study builds up a field experiment model to investigate the impacts of arching effects in the sand buffer layer on pile heads to increase the load transfer on the pile caps. The results indicate that the stress distribution on the pile cap is 10.48 times higher than the stress on the surrounding soft soil. Hence, the ground improvement method using piles and geosynthetic reinforcement can be applied to roadbeds and industrial warehouses on soft soil conditions, which helps to shorten the construction time compared to other ground treatment methods such as preloading, vacuum pumps, wick drains, etc.

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Temporal concatenation for Markov decision processes

Probability in the Engineering and Informational Sciences ◽

10.1017/s0269964821000206 ◽

2021 ◽

pp. 1-28

Author(s):

Ruiyang Song ◽

Kuang Xu

Keyword(s):

Markov Decision Processes ◽

Large Scale ◽

Optimal Solution ◽

Upper Bounds ◽

Black Box ◽

Decision Processes ◽

Optimal Solutions ◽

Wide Range ◽

Markov Decision ◽

Speed Up

We propose and analyze a temporal concatenation heuristic for solving large-scale finite-horizon Markov decision processes (MDP), which divides the MDP into smaller sub-problems along the time horizon and generates an overall solution by simply concatenating the optimal solutions from these sub-problems. As a “black box” architecture, temporal concatenation works with a wide range of existing MDP algorithms. Our main results characterize the regret of temporal concatenation compared to the optimal solution. We provide upper bounds for general MDP instances, as well as a family of MDP instances in which the upper bounds are shown to be tight. Together, our results demonstrate temporal concatenation's potential of substantial speed-up at the expense of some performance degradation.

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Application of Neural Network in Identifying Soil Strata by CPT or CPTU Data

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.945 ◽

2012 ◽

Vol 170-173 ◽

pp. 945-949

Author(s):

Jun Hai Li

Keyword(s):

Neural Network ◽

Ground Improvement ◽

Thin Layers ◽

Slope Instability ◽

General Regression Neural Network ◽

Excess Pore Pressure ◽

Soil Conditions ◽

Penetration Test ◽

Piezocone Penetration Test ◽

Tip Resistance

In geotechnical engineering, assessment of the depth location of stratigraphic interfaces and the depth and thickness of thin layers can be critical in the design process. For example, stratigraphic interfaces can promote anisotropic soil strength response and potentially provide preferential slip planes that create slope instability. Similarly, the presence of thin, high permeability layers can alter groundwater flow regimes and rates of consolidation, which can hinder or accelerate methods of ground improvement. The piezocone penetration test (PCPT or CPTU) is an extension of the cone penetration test (CPT) and is able to measure cone tip resistance, sleeve friction and generated pore-water pressures simultaneously. The piezocone’s functionality is through the measured excess pore pressure profile, which reflects changes in the drainage conditions, and therefore soil conditions. In this paper the relationship between CPTU parameters and soil types and strata is analyzed, and the structure of a general regression neural network (GRNN) is designed, and the application program is programmed with MATLAB language. The results, identifying soil strata by CPTU, have confirmed that GRNN can be used to carry out the automatically identifying soil strata.

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Investigating the Enantiodetermining Step of a Chiral Lewis Base Catalyzed Bromocycloetherification of Privileged Alkenes

Synlett ◽

10.1055/s-0036-1590951 ◽

2017 ◽

Vol 29 (04) ◽

pp. 433-439 ◽

Cited By ~ 5

Author(s):

Scott Denmark ◽

Dietrich Böse

Keyword(s):

Reaction Mechanism ◽

Lewis Base ◽

Design Criteria ◽

Significant Progress ◽

Detailed Understanding ◽

Wide Range

The development of catalytic, enantioselective halofunctionalizations of unactivated alkenes has made significant progress in recent years. However, the identification of generally applicable catalysts for wide range of substrates has yet to be realized. A detailed understanding of the reaction mechanism is essential to guide the formulation of a truly general catalyst. Herein, we present our investigations on the enantiodetermining step of a Lewis base catalyzed bromocycloetherification that provides important insights and design criteria.

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Surface bypass as a means of protecting downstream-migrating fish: lack of standardised evaluation criteria complicates evaluation of efficacy

Marine and Freshwater Research ◽

10.1071/mf18097 ◽

2018 ◽

Vol 69 (12) ◽

pp. 1882 ◽

Cited By ~ 5

Author(s):

Elena-Maria Klopries ◽

Zhiqun Daniel Deng ◽

Theresa U. Lachmann ◽

Holger Schüttrumpf ◽

Bradly A. Trumbo

Keyword(s):

Performance Studies ◽

Pearson Correlation ◽

Evaluation Criteria ◽

Fish Passage ◽

Performance Criteria ◽

Design Criteria ◽

Good Surface ◽

Wide Range ◽

Student’S T ◽

Meta Analyses

Surface bypasses are downstream migration structures that can help reduce hydropower-induced damage to migrating fish. However, no comprehensive design concept that facilitates good surface bypass performance for a wide range of sites and species is available. This is why fish-passage efficiencies at recently built bypass structures vary widely between 0% and up to 97%. We reviewed 50 surface bypass performance studies and existing guidelines for salmonids, eels and potamodromous species to identify crucial design criteria for surface bypasses employed in North America, Europe and Australia. Two-tailed Pearson correlation of bypass efficiency and bypass design criteria shows that bypass entrance area (r=0.3300, P=0.0036) and proportion of inflow to the bypass (r=0.3741, P=0.0032) are the most influential parameters on bypass efficiency. However, other parameters such as guiding structures (P=0.2181, ordinary Student’s t-test) and trash-rack spacing (r=–0.1483, P=0.3951, Spearman correlation), although not statistically significant, have been shown to have an effect on efficiency in some studies. The use of different performance criteria and efficiency definitions for bypass evaluation hampers direct comparison of studies and, therefore, deduction of design criteria. To enable meta-analyses and improve bypass design considerations, we suggest a list of standardised performance parameters for bypasses that should be considered in future bypass-performance studies.

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Modelling soil temperature and moisture and corresponding seasonality of photosynthesis and transpiration in a boreal spruce ecosystem

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-9-6419-2012 ◽

2012 ◽

Vol 9 (5) ◽

pp. 6419-6455

Author(s):

S. H. Wu ◽

P.-E. Jansson

Keyword(s):

Soil Temperature ◽

Transition Period ◽

Temperature Response ◽

Net Ecosystem Exchange ◽

Ecosystem Model ◽

Heat Fluxes ◽

Soil Conditions ◽

Eddy Flux ◽

Flux Tower ◽

Wide Range

Abstract. Recovery of photosynthesis and transpiration is strongly restricted by low temperatures in air and/or soil during the transition period from winter to spring in boreal zones. The extent to which air temperature (Ta) and soil temperature (Ts) influence the seasonality of photosynthesis and transpiration of a boreal spruce ecosystem was investigated using a process-based ecosystem model (CoupModel) together with eddy covariance (EC) data from one eddy flux tower and nearby soil measurements at Knottåsen, Sweden. A Monte Carlo based uncertainty method (GLUE) provided prior and posterior distributions of simulations representing a wide range of soil conditions and performance indicators. The simulated results showed sufficient flexibility to predict the measured cold and warm Ts in the moist and dry plots around the eddy flux tower. Moreover, the model presented a general ability to describe both biotic and abiotic processes for the Norway spruce stand. The dynamics of sensible heat fluxes were well described the corresponding latent heat fluxes and net ecosystem exchange of CO2. The parameter ranges obtained are probably valid to represent regional characteristics of boreal conifer forests, but were not easy to constrain to a smaller range than that produced by the assumed prior distributions. Finally, neglecting the soil temperature response function resulted in fewer behavioural models and probably more compensatory errors in other response functions for regulating the seasonality of ecosystem fluxes.

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Determining the Relationship between Time of Construction and Cranes Organization by Applying the Bees Algorithm for Reducing the Time of Construction of Houses

Handbook of Research on Military, Aeronautical, and Maritime Logistics and Operations - Advances in Logistics, Operations, and Management Science ◽

10.4018/978-1-4666-9779-9.ch027 ◽

2016 ◽

pp. 519-529

Author(s):

Alberto Murillo ◽

Daniel Azpeitia ◽

Perla Aquilar ◽

Yolanda Camacho ◽

Alberto Ochoa-Zezzatti

Keyword(s):

Bees Algorithm ◽

Constant Acceleration ◽

Construction Time ◽

Wide Range ◽

The Relationship

You can get a wide range of strong cranes able to lift and move heavy weights with constant acceleration, that result in an optimization in the construction time. However, it is possible that factors such as lack of cranes, incorrect cranes for work, lack of coordination, lack of communication, which result in a material is two transportation or more times occur, that once a job is done when another crane at the same time could be doing the following process. This is known as deferred construction time.

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Design of water shock tube for testing shell materials

World Journal of Engineering ◽

10.1260/1708-5284.11.1.55 ◽

2014 ◽

Vol 11 (1) ◽

pp. 55-60 ◽

Cited By ~ 2

Author(s):

H. Ji ◽

M. Mustafa ◽

H. Khawaja ◽

B. Ewan ◽

M. Moatamedi

Keyword(s):

Shock Tube ◽

Failure Mechanisms ◽

Design Parameters ◽

Experimental Setup ◽

Design Considerations ◽

Applied Pulse ◽

Wide Range ◽

Impulsive Loads ◽

Shock Impact ◽

Experimental Rig

This paper presents design considerations for a shock tube experimental rig used to investigate the dynamic failure mechanisms of shell geometries subjected to water shock impact loading. In such setup, it is desirable that the drive pressure used within the tube can provide a wide range of impulsive loads on the test structures and some flexibility can be achieved on the applied pulse durations. With this aim a review of various existing shock tube experimental setup is presented and choices are made based on scientific merits. Finally design parameters are drawn for right set of conditions required for the experiments.

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Simulation of the Responses of Dry Beans (Phaseolus vulgaris L.) to Irrigation

Transactions of the ASABE ◽

10.13031/trans.12386 ◽

2017 ◽

Vol 60 (6) ◽

pp. 1983-1994 ◽

Cited By ~ 2

Author(s):

Mónica Espadafor ◽

Lairson Couto ◽

Morethson Resende ◽

Delbert W. Henderson ◽

Margarita García-Vila ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Simulation Model ◽

Soil Water ◽

Yield Response ◽

Soil Conditions ◽

Dry Beans ◽

Phaseolus Vulgaris L ◽

Management Options ◽

Crop Simulation ◽

Wide Range

Abstract. AquaCrop is a crop simulation model developed by the FAO aimed at assessing the yield response to water supply. Once the model is calibrated and validated, it is a useful tool to simulate crop yields under different management options or climatic and soil conditions. Until now, AquaCrop has not been parameterized for dry beans ( L.), and thus our objective was to calibrate and validate the model for this crop using experiments performed 40 years ago at Davis, California. A set of parameters derived from the calibration with one irrigation experiment was used to validate the model using five experiments carried out in 1977 and 1978 that had treatments vastly differing in irrigation depth and frequency. Yield predictions over a wide range of values (<1 to 3.5 t ha-1) were very good, with RMSE of 0.16 t ha-1 and Willmott’s d of 0.978. Seasonal ET was also accurately predicted by the model (RMSE = 40 mm, d = 0.930), as also evidenced by comparing the lysimeter measured ET of 489 mm against the lysimeter simulated ET of 501 mm. Canopy cover and the time course of biomass were adequately simulated as well. Even though total soil water extraction was well simulated, the simulated soil water distribution with depth differed from measured values in the dryland treatment. We conclude that AquaCrop can now be used for the simulation of dry beans in different environments, and we emphasize the value of carefully conducted field experiments for the validation of crop simulation models. Keywords: AquaCrop, Calibration and validation, Dry beans (Phaseolus vulgaris L.), Irrigation, Simulation model, Water stress.

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