Use of Micropiles for Foundations of Transportation Structures Final Report

In pile design, piles must be able to sustain axial loads from the superstructure without bearing capacity failure or structural damage. In addition, piles must not settle or deflect excessively in order for the serviceability of the superstructures to be maintained. In general, settlement controls the design of piles in most cases because, by the time a pile has failed in terms of bearing capacity, it is very likely that serviceability will have already been compromised. Therefore, realistic estimation of settlement for a given load is very important in design of axially loaded piles. This notwithstanding, pile design has relied on calculations of ultimate resistances reduced by factors of safety that would indirectly prevent settlement-based limit states. This is in part due to the lack of accessible realistic analysis tools for estimation of settlement, especially for piles installed in layered soil. Micropiles have been increasingly used, not only as underpinning foundation elements but also as foundations of new structures. Prevalent design methods for micropiles are adaptations of methods originally developed for drilled shafts. However, the installation of micropiles differs considerably from that of drilled shafts, and micropiles have higher pile length to diameter ratios than those of drilled shafts. Improved understanding of the load-transfer characteristics of micropiles and the development of pile settlement estimation tools consistent with the load-transfer response of these foundation elements are the main goals of the proposed research. A rigorous analysis tool for assessment of the load-settlement response of an axially loaded pile was developed in this study. We obtained explicit analytical solutions for an axially loaded pile in a multilayered soil or rock. The soil was assumed to behave as a linear elastic material. The governing differential equations were derived based on energy principles and calculus of variations. In addition, solutions for a pile embedded in a multilayered soil with the base resting on a rigid material were obtained by changing the boundary conditions of the problem. We also obtained solutions for a pile embedded in a multilayered soil subjected to tensile loading. We then compared our solutions with the results from FEA and also with other solutions available in the literature. Finally, we compared the results of a pile load test from the literature with the results obtained using the solutions proposed in this study. Using the obtained elastic solutions, we also performed extensive parametric studies on the load-transfer and load-settlement response of rock-socketed piles. The effects of geometry of rock socket, rock mass deformation modulus, and in situ rock mass quality were investigated. To facilitate the use of our analysis, a user-friendly spreadsheet program ALPAXL was developed. This program is based on the elastic solution obtained in this study and uses built-in functions of Microsoft Excel. ALPAXL provides the results of the analysis, the deformed configuration of the pile-soil system and the load-settlement curve in seconds. It can be downloaded at http://cobweb.ecn.purdue.edu/~mprezzi. In the context of an INDOT project, a fully instrumented load test was performed on a rock-socketed micropile. The results of this micropile load test, on a pile with high slenderness ratio and high stiffness of surrounding rock, confirmed that most of the applied load was carried by the pile shaft. The shaft capacity of hard limestone obtained from the load test at the final loading step was 1.4 times larger than the shaft capacity that is obtained using the highest value of limit unit shaft resistance suggested by FHWA (the limit unit shaft resistance qsL from the load test was 2950 kPa, while the suggested values from FHWA were 1035 – 2070 kPa). Using pile and soil properties, predictions were also made using ALPAXL. The results from ALPAXL were in good agreement with the measured data at the design load level

Calibration of Resistance Factors for Driven Piles using Static and Dynamic Tests

The field of geotechnical engineering has evolved from Allowable Stress Design (ASD) to Load Factor and Resistance Design (LRFD) which has led to a need to quantify the measures of uncertainty and the level of reliability associated with a project. The measures of uncertainty are quantified by load and resistance factors, while the level of reliability is driven by the amount of risk an owner is willing to take and is quantified by the reliability index. The load factors are defined through structural design codes, but the resistance factors have uncertainties that can be mitigated through reliability based design. The American Association of State Highway and Transportation Officials (AASHTO) have recommended resistance factors that are dependent on the type of load tests conducted and are available as a reference to state agencies. The objective of this study was to improve the AASHTO recommended resistance factors used by the Arkansas State Highway and Transportation Department (AHTD), thereby, increasing allowable pile capacity and reducing deep foundation costs. Revised resistance factors for field acceptance based on dynamic testing were established through the analysis of pile load test data where both static and dynamic load testing was conducted. Pile load tests were separated by pile type and soil type. It was important that the load test data analyzed represented soil and geologic conditions similar to those found in Arkansas. The resistance factors determined from this analysis improved AHTD current practice, but indicated that the factors recommended by AASHTO may be unconservative for this region

Two driven pile load tests for use in Missouri LRFD guidelines

A static pile load test program was initiated by the Missouri Department of Transportation (MoDOT) to evaluate the use of pile load tests in Missouri LRFD guidelines. The program\u27s approach involves two phases to achieve the appropriate levels of reliability for driven piles in the state of Missouri. This thesis focuses on the data collection efforts of Phase 1. Two quick static pile load tests were performed to failure on test piles in the Southeast Lowlands geologic region of Missouri. The piles were dynamically monitored during installation and subsequent restrike tests performed. The results of the static and dynamic pile testing were evaluated and interpreted. Overall, the nominal resistances predicted by dynamic tests (CAPWAP) at beginning of restrike (BOR) compared well to the results of the static load tests evaluated using Davisson\u27s method (at these specific sites). A comparison of the load transfer distributions from the dynamic and static load tests provided mixed results. The effects of pile set-up after driving are a significant factor to consider in determining the need for a restrike. The additional resistance available following pile setup can have a substantial effect on the nominal resistance determined using dynamic methods. When BOR capacities are measured using dynamic methods they can be used with confidence for the calibration of resistance factors with respective pile types and geologic units. Available pile load test data sets from Missouri\u27s neighboring states and previous efforts conducted in Missouri were compiled as well. Two recently available pile load test databases were evaluated and considered for the upcoming phase to conduct calibration of resistance factors. --Abstract, page iii

OPTIMUM DESIGN OF RETAINING WALL FOR EARTH RETAINING STRUCTURES OF DIFFERENT HEIGHT

Retaining walls are usually classified as geotechnical structures. Retaining wall can be either earth retaining wall or water retaining wall. For earth retaining wall, it is generally used to provide lateral support for an earth fill, embankment, or some other material and to support vertical loads. One primary purpose for these walls is to maintain a difference in elevation of the ground surface on each side of the wall. The earth whose ground surface is at the higher elevation is commonly called the backfill, and the wall is said to retain this backfill. The main objective to be achieved by this project is to investigate the optimum height of different types of retaining wall. As the problems regarding the slope failure and land sliding is becoming more significant in the Peninsular Malaysia, the study on how to minimize or even to eliminate the risks of these problems are crucial. The optimum height of different types of retaining wall should be detem1ined and the design needs to be optimized to provide the best rectification possible. In order to determine the optimum height of different types of retaining walls such as cantilever wall, counter-fort and buttress wall, macros on Excel spreadsheet programs to be develop. Based on the most critical parameters such as soil properties, surcharge pressure, and etc the optimum height can be obtained and then the design is to be optimized

Regression Analysis to Determine the Reserve Strength Ratio of Fixed Offshore Structures

This study estimates the Reserve Strength Ratio (RSR) of fixed offshore structures with the utilization of regression analysis, which is capable in replacing the conventional expensive and time consuming methods currently adapted in the oil and gas industry. Offshore structures from the three regions of Malaysian Waters namely Peninsular Malaysia, Sarawak and Sabah were used to perform the analysis of different jacket configurations and sea-states accordingly. The pushover analysis of this study was performed by SACS program version 5.3 and the regression analysis was done using Microsoft Excel. Finding has revealed that regression analysis is able to produce regression coefficients to formulate non-linear regression equations fitting to the set of data to estimate the platform RSR

Applying project management techniques to improve due date performance: the case of a papua power plant construction in Indonesia

Obstacles can occur on a project causing nonconformance in terms of time and cost. A Power Plant in Indonesia is being constructed and the project was still underway, when a delay was anticipated. In this case, the construction progress was only 13.1% on day-92, while it should have been completed around 26.4% to finish within 184 days. This thesis purpose is to identify and analyze the delay causes, by applying Critical Path Method (CPM) and Project Evaluation Review Technique (PERT) methods. Data concerning project activities and three estimation times were collected from internal reports and semistructured interviews, as follows: optimistic, most likely, and pessimistic durations. A project schedule and the critical path were computed by using Microsoft-Excel and Microsoft-Project software to operationalize PERT/CPM methods. These results were analyzed using of s-curve, network diagram and probability calculation, to anticipate the due date achievement level. The delay causes were collected by subsequent interview and treated by the Fishbone Analysis, which enabled the following categorization of failures: labor, machine, material, environment and method. These provided support for managers to take action. Finally, a discussion concerning the traditional methods of Project Management, i.e., Design-Bid-Build, suggests that Building Information Modelling (BIM) could generate better synchronization among stakeholders, by eliminating the major source of delays. Also, the Life Cycle Assessment was found necessary to decrease carbon dioxide emissions, so the building could achieve more sustainable performances. Moreover, integrating BIM, Building Energy Modelling and LC Energy Analysis was suggested to improve project sustainability.Num projecto, há obstáculos que podem causar não-conformidades, no tempo e custo. No caso em apreço, antecipou-se um atraso numa Central Hidroelétrica em construção. No dia 92, o avanço da construção era de apenas 13,1%, enquanto deveria ter sido concluído 26.4%, para ser possível terminar o projecto em 184 dias. O objetivo desta dissertação é identificar e analisar as causas de atraso, aplicando o Critical Path Method (CPM) e a Progam Evaluation and Review Technique (PERT). Os dados relativos às atividades do projeto e às estimativas de tempos otimista, mais-provável e pessimista foram recolhidos em relatórios e entrevistas semi-estruturadas. O cronograma e caminho crítico foram calculados através do Microsoft-Excel e Microsoft-Project que operacionalizam os métodos PERT/CPM. Para antecipar o cumprimento da data de entrega prevista, esses resultados foram analisados através da s-curva, diagrama de rede e cálculo de probabilidades. As causas de atraso foram recolhidas por consequentes entrevistas e tratadas pela Análise-de-Espinha-de-Peixe, o que permitiu a categorização das falhas em mão de obra, máquina, material, ambiente e método. Finalmente, uma discussão sobre os métodos tradicionais de gestão de projetos, ou seja, DesignBid-Build sugere que o Building Information Modelling (BIM) poderia gerar melhor sincronização entre as partes interessadas, para eliminar a principal fonte de atrasos. Além disso, a Avaliação do Ciclo de Vida foi considerada necessária para diminuir as emissões de CO2, para que o edifício pudesse atingir um desempenho sustentável. Também foi sugerida a integração entre BIM, Building Energy Modeling e LC Energy Analysis para melhorar a sustentabilidade do projeto

Perencanaan Ulang Jembatan Jurug Jln.Ir.Sutami Dengan Sistem Balok Prategang Mengacu Pembebanan RSNI T-02-2005

The purpose of final project is to know prestressed concrete bridge construction design rules which is right, so it needs calculation relats to the standard with bridge redesigning of Jln.Ir.Sutami, Solo, Central Java. The bridge is class 1 has span of 175 m with 4 girders spans on its pier. The rules are used for refrence is rule of SNI T-02-2005 and redesign guidliness of Bridge Management System (BMS) 1992 in determining loading standard for bridge construction. Construction mechanic analysis is used for finding inside force which happens with using SAP 2000 V 15 Program. The methematic calculation in finding fast and accurat result used “Microsoft Excel 2013”program. Wherease, drawing used “AutoCAD 2012” program and “Sketchup 2015”program. This redesign is got 46 meters of girder with 2,3 meters of girder profile and for 41 meters of girder is got 2,1 meters of profile, for tendon which is used to 46 meters of girder and 41 meters is got 5 tendons and 4 tendonson longitudinal girder. In calculation of longitudinal 46 meters of girder did loss of prestress of 16,525 % and on ll 41 metersof longitudina did 16,879 % of loss of prestress . Longitudinal to stress , deflection, limit moment and shear force On bridge abutmentto be main 6 parts are breast wall, back wall, corbel, wing wall, pile capand bore pile foundaiton, wherease for pier is devided becomes 5 parts are headstock, column pier, beam diapragma, pile cap and bore pile foundation. keywords :redesing, Jurug, prestressed concrete, bridge, borepile

Ultimate pile capacity of bored pile and drivenpile at ara damansara using bayesian inverse menthod

This paper presents the analysis of the actual and designed ultimate pile capacity, and the application of Bayesian approach for inverse analysis as a method to obtain the unit shaft resistance and the unit base resistance based on the pile load test results at Ara Damansara. The result for this project is limited to the area around Ara Damansara only