Pile Cap Research Articles

The selection of an appropriate concrete mixture for casting a pile cap in hot weather using 3D finite element model

In this study, the finite element model (FEM) was developed to select an appropriate concrete mixture for a large heavily reinforced bridge pile cap located in Qassim region of Saudi Arabia. The pile cap with dimensions of 9 m x 9 m in plan and 1.8 m in depth was exposed to hot weather conditions in summer season. The heat of hydration in mass concrete results in high temperature gradients across the depth of the concrete creating excessive thermal stresses resulting in micro-cracking at the surface. The concrete mixtures with 30% date kernels ash, 30% fly ash, 30% natural pozzolan, 30% limestone powder, 30% ground granulated slag and 60% ground granulated slag were investigated. The experimental investigations were conducted on the concrete mixtures to determine the mechanical properties, such as tensile and compressive strength, thermal properties, such as thermal conductivity, specific heat, and thermal resistivity, and heat of hydration. The chemical compositions of ordinary Portland cement, date kernels ash, fly ash, natural pozzolan, limestone powder and ground granulated slag were analyzed using wavelength dispersive X-ray fluorescence (WDXRF). Based on the experimental and finite element model results, the concrete mixtures with 30% fly ash (FA), 30% ground granulated blast furnace slag (GGBFS), and 60% GGBFS were found to be less prone to cracking. Notably, the mixture with 60% GGBFS demonstrated the lowest likelihood of cracking, leading to its selection for casting the pile cap.

Behavior of Large Pile Caps Subjected to Column Uplift

Behavior of Large Pile Caps Subjected to Column Uplift

Field and Numerical Study of the Bearing Capacity of Pre-Stressed High-Strength Concrete (PHC)-Pipe-Pile-Reinforced Soft Soil Foundations with Tie Beams

Pre-stressed high-strength concrete pipe piles (PHC pipe piles) have been widely used in actual soft foundation treatment projects due to their reliable quality, fast construction, assembly line production, and environmental friendliness. However, large-scale slip damage still occurs in construction projects. In order to reduce and avoid such accidents, a highway in Guangdong (section K31+100~K31+388) was taken as an example for this study. Plaxis 2D software (V22.01.00) was used to establish a PHC pipe pile composite roadbed model and investigate the effects of tie beam form, pile lengths, pile spacings, pile verticality, and embankment filling loading modes on the settlement and stability of the composite roadbed. The results show that the original treatment plan, which had the form of a PHC pipe pile with caps, had a low horizontal bearing capacity and a poor anti-disturbance ability, leading to the occurrence of a landslide accident. A comparison of different structural forms revealed that the longitudinal and transverse tie beam form was the most stable, followed by the transverse tie beam form, longitudinal tie beam form, PHC pipe pile form with caps, and PHC pipe pile form without caps. Compared to the structural form of PHC pipe piles with pile caps, the stabilities of the transverse tie beam form and the longitudinal tie beam form were improved by 42.47% and 38.61%, respectively, while that of the longitudinal and transverse tie beam form was improved by 50.87%. The application of longitudinal and transverse tie beams effectively reduced the settlement of the composite roadbed, as confirmed by both measured data and finite element analysis. This structure achieved the desired vertical settlement control and lateral anti-slip effects.

Seismic Damage Analysis of Pile Foundation on Liquefiable Sandy Soil Foundation

Under the action of cyclic dynamic loads caused by earthquakes, the sandy soil foundation will liquefy, which may easily lead to damage to the pile foundation. For example, the soil liquefaction will cause pile foundation subsidence, the failure of the connection between pile cap and cap, and the beam drop caused by pile foundation moving sideways with soil. There are many influencing factors of foundation liquefaction, and the influence of many factors on foundation liquefaction is highly nonlinear. The author analyzes the liquefaction principle of sandy soil foundation and combines the seismic damage data of pile foundation with the experimental data of large-scale shaking table. Then this paper describes the damage and failure characteristics of pile foundation on liquefied sandy soil foundation.

Lateral Response of 2 x 2 Pile Group Embedded in Cohesive Soil Near Slope

This work studies the response of a 2 x 2 pile group near a slope subjected to lateral load. Three-dimensional, non-linear finite element analysis is carried out. The entire code is developed in FORTRAN 90. Bending-dominated pile and pile caps are represented by 20 node elements with quadratic shape function, and shear-dominated soil elements are represented by eight-node elements with linear shape function. Sixteen node interface element of zero thickness is used for stress transfer between pile and soil. The outcome highlights the influence of slope parameters like slope angle and edge distance on the response of the 2 x 2 pile group near a slope. The lateral displacement and maximum bending moments are increased with an increase in slope. However, its effect reduces with an increase in slope distance. The point of zero-shear along the pile's depth shifts deeper with an increase in slope.

Numerical Analysis of the Stability of Bridge Foundation Pile under Earthquakes Effect

This study was chosen because of the entry of our regions into the seismic zone recently, where Diyala governorate was hit by the Halabja earthquake in 2017 by 7.3Mw. Therefore, the impact of earthquakes will be studied on the AL-Mafraq bridge foundations piles located in Iraq- east of Baghdad in Diyala Governorate and the extent of its resistance to the Halabjah, EL-Centro, and Kobe earthquakes with acceleration 0.1g, 0.34g, and 0.58g respectively. After modeling and performing the analysis by using Midas Gts-Nx software, the settlement (mm) results at nine nodes (four nodes for the pile cap and five nodes for the piles) were obtained for each of Halabjah, EL-Centro, and Kobe earthquakes to know the resistance of the bridge foundation and which intensity leads to the failure happen. After conducting the analysis, I found the maximum settlement is equal to 11.95 mm with a time of 443 sec at node 3 resulting from the Halabjah seismic, and 49.47 mm from the EL-Centro seismic with a time of 254 sec at node 3. They are within the allowable limits of settlements, but the maximum settlement resulting from the Kobe earthquake equals 359.9 mm with a time of 565 sec at node 3. So, the Kobe earthquake led to failure in the pile's foundation Halabjah earthquake and Centro did not affect the stability of the pile's foundation, Based on Terzaki's theory 1943.

Modeling of Heat Transfer in Massive Concrete Foundations Using 3D-FDM

Analyzing and modeling the thermal behavior of mass concrete elements has been widely investigated by several researchers. Lately, many contemporary finite element packages have embedded modules for analyzing thermal behavior. Unfortunately, these packages are quite complex and require experts to be properly implemented. This paper proposes a simple and practical approach using the 3D-Finite Difference Model (3D-FDM) developed by MS-Excel to overcome the complexity of the other FE models. The model is utilized to predict the thermal behavior of actual bridge pile caps (3D model) rather than the previously developed 2D models in earlier research. The results of the analysis are compared with the concrete temperatures that were experimentally obtained from the site. Site data was collected using 18 thermocouple probes (K type) that were installed in two pile caps. These thermocouples were installed before concrete pouring to monitor the temperatures generated due to the exothermic reaction of the cement, which occurs during casting and the maturity period of concrete. The readings were registered every 3 hours for 7 days after concrete placement. This research provides a comparison between the recorded site data and the thermal analysis based on the proposed 3D-FDM. Results proved that concrete temperature time histories at different locations of the bridge pile caps could be properly predicted using the developed 3D-FDM. Doi: 10.28991/CEJ-2023-09-10-05 Full Text: PDF

Fundamentals of Construction Materials and Types of Building Using WPM Method

Building materials are construction materials. Natural resources such as branches, wood, clay, pebbles, and sand can all be used to build. Many naturally occurring compounds and some more and some less artificial man-made items are in use. Building materials are called from a range of sites and quarried and mined as jio goods. Must find new resources because the demand to cling to what is now available is expanding along with the world's population. Concrete has a long and illustrious history, but adobe bricks, stone, and clay were the primary building materials used throughout history. These products are still in demand, and any more quarry for their specific extractive industries in the same area causes issues. this is a list of construction supplies. Buildings and structures produce several types of building materials that are employed in the construction sector. Construction is used for projects to specify materials and processes, and project managers' materials and goods are utilized in this category by architects and construction. Blockwork, typically wood building materials, and cold, rolled steel frame are all considered modern construction techniques as opposed to slow ones. There are several applications for various building materials; as a result, you should always check with the manufacturer to be sure a product is good for your needs. Around the world, almost 11,000 new structures are constructed each day. Buildings, sidewalks, and skyscrapers the first being undersea constructions, mines, and bridges for building products, numerous structures up to various construction are used. This page discusses the various types of construction materials used in construction. A hotel and residential complex in midrice the trust is now in motion. Supported by types and earth steel wallers around the excavation the pile also holds the steel sheet. The equipment enters, and the image travels down the earth's curve before leaving the spot. On the right, is a large backhoe from the previous structure there following the ancient mounds around digging continues but pressure-painted setting up the concrete pile legs what is happening, in the movie, better-completed piles are visible in the nearby center and the far corners. Piledrivers in large groups work. Strengthening of columns and concrete pile caps construction is underway on an excavation in the middle of the center. A well-liked technique for multi-criteria decision analysis (MCDA) and multi-criteria decision making (MCDM) is the weighted product model (WPM). The weighted sum model is comparable to this (WSM). The primary distinction is that multiplication is used as the primary mathematical operation rather than addition. The decision-making model by multiplication in linking an attribute rating includes the Weighted Product (WP) technique. When attributes are multiplied, weight for attributes acts as a positive rank, whereas attribute rating acts as a negative rank for the cost attribute. Materials, Construction equipment, Labor, Finance, Enabling Expenses, Admin Expenses, Surplus Building, Roads, Bridges, Dams, Power, Railway, Mineral Plant, Transmission the result it is seen that Dams is got the first rank where as is the building is having the lowest rank. Dams is ranked first and industrial Building is ranked lowest.

Discovering key factors and causalities impacting bridge pile resistance using Ensemble Bayesian networks: A bridge infrastructure asset management system

Bridges are one of the critical infrastructure systems and play a critical role in supporting the economic development of nations. During the planning, design, and construction phases of bridges, it is important to ensure that the different bridge components satisfy the desired performance for avoiding catastrophic failure. One example is the foundation system with deep driven piles. A crucial consideration when planning, designing, and constructing bridge foundation system is to accurately estimate the pile resistance (i.e., capacity). However, this process constitutes a considerable challenge for bridge managers and engineers due to the uncertainties, subjectivities, and biases involved in providing accurate estimates. In fact, the current design process of bridge pile foundations is still performed in a relatively simple and deterministic manner. Thus, there is still a lack of studies that were conducted to effectively represent the causalities between different variables impacting the bridge pile resistance using objective, data-driven methods rather than subjective, expert-based methods. Therefore, this paper addresses this knowledge gap by proposing a data-driven, knowledge-discovery Bayesian network model as an expert system to (1) identify the key factors impacting the performance of bridge piles through data-driven knowledge discovery; (2) capture the causal (direct and indirect) relationships between the different variables that influence bridge pile resistance, and (3) predict bridge pile resistance in support of decision making in bridge design and construction. Multiple Bayesian network models were developed using two distinct learning paradigms based on a pile dataset with 18 variables and 2,375 data samples from a large bridge project. One paradigm is to run a regular process for learning graphical models using Bayesian structure learning, while the other one is to couple Bayesian networks with bagging ensemble learning. Model validation results showed that the best model learned by bagging ensemble learning paradigm achieves the highest prediction accuracy of 89.78% for predicting bridge pile resistance. Additionally, the developed Bayesian network models identify 8 critical factors affecting bridge pile resistance. These factors are categorized into four groups, including the external applied force on pile head, pile mechanical property (i.e., compressive stresses in bridge piles), hammer property and operation characteristics (e.g., hammer blow count), and pile cap elevation. The observations from this study would assist bridge managers and practitioners in decreasing the uncertainties that impact the estimation of pile capacity, and thus help in balancing cost-effectiveness with good performance. The paper adds to the body of knowledge by providing a great deal of insights related to the factors and causalities influencing the performance of deep bridge foundations to ultimately help in the plan, design, and construction phases of bridges.

Topology Optimization: Applications of VFLSM and SESO in the Generation of Three-Dimensional Strut-and-Tie Models

Topology Optimization: Applications of VFLSM and SESO in the Generation of Three-Dimensional Strut-and-Tie Models

Shaking table test and numerical investigation of seismic response of pile-supported wharves with batter piles

Batter piles control displacement of wharves and offshore platforms by absorbing most earthquake and berthing loads because of their high lateral stiffness. Nevertheless, structural failure caused by stress concentrated in the pile caps has been reported in past earthquakes. The present paper investigates the seismic performance of wharf models with and without batter piles using 1 g shaking table tests with harmonic excitation as well as real earthquake records. Sensitivity analysis was performed by studying the effect of the deck load, shaking frequency, embedment depth of the pile and the relative density of the soil on horizontal displacement and acceleration of the deck. A numerical investigation was conducted using 3D finite element method to evaluate the role of the pile inclination angle on the behavior of the pile-supported system. The results of dynamic analysis quantitatively indicated the defects in the batter piles under different conditions. It was also concluded that, although the amount of deck displacement decreased when the inclination angle was reduced, the axial force generated in the batter piles showed no upward or downward trend and maximized at a specific angle.

A COMPOSITE MODELLING APPROACH FOR THE RETROFITTING AND REHABILITATION OF AN HISTORICAL COASTAL ASSET

The Pont del Petroli pier is a coastal structure located in the coastal town of Badalona, north of Barcelona, in Spain. The pier was built in the 60s to allow mooring of petroleum tankers, but fallen in disuse in 1990. Restored between 2003 and 2009, the pier is now regarded as a historical and social asset of the Catalan coast. In January 2020 the storm Gloria (Amores et al., 2020), characterized by extreme wave conditions (recorded offshore significant wave heights in excess of 8.5 m) and lasting for nearly two days, caused flooding events, casualties and severe damages to several structures in Spain. The pier head platform was damaged, four supporting piles failed and part of footbridge beam was washed away. There is no recorded wave climate that hit the pier so strong during its 50-year life. To reproduce the conditions that led to the failure of the pier a compositemodelling has been carried out at Universitat Politènica de Catalunya (UPC). The outcomes of the work provide further insight and information on the interaction between waves and the key pier elements (platform, footbridge, piles, pile caps) and aided the design for the structural retrofitting, including the study of four different alternatives for the pier head platform and the footbridge attached to it.

The Effect of the Piles Cap Elevation on Local Scour around Complex Bridge Piers

The Effect of the Piles Cap Elevation on Local Scour around Complex Bridge Piers

Effects of cyclic loading on soil arching within pile-supported embankment with artificial crust: A coupled DEM-FDM approach

This study endeavors to investigate the evolution of soil arching within pile-supported embankments featuring artificial crusts under cyclic loading. A quasi-three-dimensional (quasi-3D) model was formulated utilizing the Discrete Element-Finite Difference coupled method (DEM-FDM) and validated by in-situ vibration tests. The mechanism underlying the soil arching weakening due to cyclic loading was elucidated, and the impacts of artificial crust moduli and thicknesses on soil arching were consolidated. The findings demonstrate that the equal settlement section moves upwards, and the lower limit of the settlement trough resulting from cyclic loading extends downward with an escalation in axle load, but these remain relatively consistent as the loading velocity increases. Additionally, the transmission of dynamic stress from the pavement surface to the outer surface of the arch approximately adheres to the Boussinesq formula, whereas the stress propagation from the outer surface to the top of the pile cap conforms to the prescribed dynamic pile-soil stress ratio. Furthermore, increasing the thickness and the elastic modulus of the artificial crust contributes to diminished pile-soil differential settlement, alteration in the pile-soil stress ratio, lowered susceptibility of artificial crust deflection to cyclic loading, reduced anisotropy coefficient, and a counterclockwise rotation in the primary direction of the normal contact force exerted on particles within the arch region.

Experimental and Numerical Investigation of Geosynthetic-Reinforced Pile-Supported Embankments for Loose Sandy Soils

This research focuses on advancing the geosynthetic-reinforced pile-supported embankment technology over loose sandy soil. A small-scale laboratory model supported by floating piles and a geotextile layer was constructed, and a numerical model was validated against laboratory measurements. This study aims to achieve a more uniform distribution of the load over all piles of the system via a parametric study that analyzes the influence of embankment fill material, horizontal reinforcement scenarios, pile cap shape, and pile type. The results demonstrate that using embankment fill with high cohesion and internal friction properties leads to a significant reduction of 46% and 37% in maximum settlements, respectively, and similarly, results in a noteworthy reduction of 48% and 50% in differential settlements. The incorporation of two geotextile layers contributes to a reduction of up to 30% in maximum settlement. The utilization of plus-shaped caps in small areas, with an area equal to three times the cross-sectional area of the pile, has been substantiated as the preeminent approach for the reduction of settlements. Piles with caps also present better behavior regarding differential settlements compared to longer piles and piles with bigger diameters under the same volume condition.

Pengaruh Penambahan Gula Pasir Terhadap Kuat Lentur Beton Dengan Perendaman Air Laut

Innovations in concrete design continue to be made to obtain maximum strength. The granulated sugar can be an added ingredient that functions to inhibit the concrete setting time so it doesn't dry out too quickly. Use to delay concrete setting time (setting time) for example with hot weather conditions, or extend compaction time to avoid cold joints and avoid the impact of settlement when fresh concrete is carried out at the time of casting. As for the curing experiment/treatment of the concrete by immersion in seawater to find out how construction buildings on the seaside affect construction such as bridge abutments, pile caps or buildings on the coast that are submerged or exposed to sea water whether there is a decrease in the quality of making concrete blocks. The experiment was carried out by adding a variety of granulated sugar to the concrete mixture of 50 grams (2% by weight of water), 70 grams (3% by weight of water) and 100 grams (4% by weight of water) then all the samples were immersed in sea water. Based on the results of the flexural strength test of concrete after 28 days of age, the highest test results obtained for the flexural strength of concrete were the addition of 100 grams of granulated sugar worth 3.00 MPa for the second was the addition of 50 grams of granulated sugar worth 0.515 MPa and for the third was the addition of sugar sand 70 grams 0.454 Mpa. This composition cannot be said to have decreased due to immersion in sea water, because there is no proven comparison with immersion using ordinary water.

Investigation of residual protection of a 55 years old marine structure after 20 years subject to impressed current cathodic protection

It has been reported that structures to which impressed current cathodic protection (ICCP) has been applied for a long period have displayed evidence of residual protection when ICCP has been halted, ranging from several days up to significantly longer periods. To study this phenomenon this paper reports the de-activation of a 20 years old ICCP system installed on a 55 years old wharf structure. The ICCP was de-activated for 84 days and the reinforcing steel potentials at locations on the front pile cap and front wall were monitored via the existing installed reference electrodes (RE). The results showed that all the RE installed in the structure initially demonstrated a positive shift in potential, with 61% maintaining a positive trend over the entire trial period.

Effects of excavation and construction sequence on behavior of existing pile groups

In congested urban areas, new structures are regularly constructed next to high-rise buildings. At different stages of excavation for the new structures, settlement and tilting of the adjacent piled buildings may be occurred. Thus, attention here will be focused on the interaction behavior between deep excavation and adjacent piled foundations. Accurate prediction of soil movement and pile response plays an important role in preventing damages to adjacent buildings. Finite-element models are employed to compute the pile group responses. The parametric study has been performed by varying pile group configurations, center-to-center pile spacing, and new building load. Two, four, and six capped head pile groups next to excavation sites have been examined. In this paper, discussion centers on settlement and tilting of the pile groups nearby an excavation in fully saturated sand. The influence of pile group configuration and new building loads are systematically investigated. New building can be constructed in the excavated area after completion of the excavation. The effect of new building construction sequences is also investigated. Results provide confirmatory evidence that, excavation depth has the most significant effect on pile settlement and pile cap tilting. High pile cap tilting and small pile group settlement are apparent in case of two piles near the excavation. For the four pile group, the induced tilting of pile cap decreases as spacing between the piles increases. Due to construction of the new building, the settlement is exacerbated but the tilting is moderated.

Analysis Methods for the Design of Pile–to–Pile Cap Connections Concerning Plain Pile Embedment

Analysis Methods for the Design of Pile–to–Pile Cap Connections Concerning Plain Pile Embedment

Modifikasi Perencanaan Pondasi Borepile Sebagai Alternative Pengganti Pondasi Minipile Proyek Gedung Madrasatul Qur’an Jombang

The Borepile Foundation and the Implementation Method for the Madrasah Aliyah Madrasatul Qur’an Tebuireng Jombang Building Project, is one of the deep foundation. The use of borepile foundation is an alternative to minipile foundation. Calculation of building weight using the SAP2000 program. The points reviewed are points S-1 and points S-2. Pile bearing capacity analysis using the Mayerhoff method. By using sondir soil evidence (CPT). The construction of the Madrasah Aliyah Madrasatul Qur’an Tebuireng uses a diameter of 80 cm for borepiles with a depth of 11 m and has 23 D22 reinforcement. There are 4 types of pile caps in the borepile. The dimensions of each pile cap, namely PC-1, PC-2, and PC-4, are 150 cm x 150 cm, while PC-3 is 150 cm x 100 cm. For reinforcement in the x-axis direction of 22 D22 – 150 mm, reinforcement in the y-axis direction of 24 D22 – 160 mm. In the implementation method using a mini borepile because it considers aspect of heavy equipment mobilization. Some of the work in progress includes measuring, making reinforcement, drilling, installing reinforcement, casting, and making pile caps.