Pile Cap Foundation Research Articles

Perencanaan Gedung Bertingkat 5 Lantai Asrama Putri Pondok Pesantren Hasyim Asy’ari Bangsri Jepara

The development of the world of Islamic education in Indonesia also includes Islamic boarding schools, Hasyim Asy'ari Bangsri Jepara Islamic boarding school is one of the best Islamic boarding schools, to support the smooth teaching and learning, it is necessary to have adequate student facilities and facilities. This research aims to help fulfill the capacity of santri facilities and infrastructure at the Hasyim Asy'ari Bangsri Jepara Islamic boarding school. The building structure calculations were reviewed for dead loads, live loads and earthquake loads using the SAP 2000 program. The structural calculations carried out included roofs, floor plates, beams, columns, stairs, sloofs and foundations. The building planning location is Jl. Jepara-Bangsri No. 9, Krasak Bangsri, District. Bangsri, Kab. Jepara, Central Java 59452. From the structural planning, the roof structure is obtained with 2L steel trusses 50.50.7, floor plate 130 mm ∅ 12-100, beam B1 500x300 mm 10 D19, beam B2 400x250 mm 10 D19, column K1 500x500 mm 18 D19, column K2 400x400 mm 12 D19, ladder plate thickness 150 mm ∅ 12-150, sloof 500x300 mm 9 D19, pile cap foundation 160x160x60 mm, pile D30 cm 6 m long, with concrete quality (f'c) = 30 MPa, reinforcement quality (fy) = 400 MPa and (fy) = 240 MPa. The programs used are Microsoft Office, Microsoft Excel, Autocad, SAP 2000, and SketchUp.

Nonlinear buffeting responses of a coastal long-span bridge under the coupled wind, wave and current loads

The buffeting responses of sea-crossing bridges pose significant challenges due to the diverse terrain in the bridge region and intricate coupling effects between the environmental variables and structures. A novel Wind-Wave-Current-Bridge (WWCB) framework is proposed to assess the buffeting responses of coastal long-span bridges under coupled wind, wave, and current loads. By employing measured wind and wave data, the optimized C-vine copula and Ekman drift current theory are utilized to establish correlations among four environmental variables, namely wind speed, wave height, wave period, and current velocity. The nonlinear wave loads acting on the pile-cap foundations are computed using the potential flow theory and boundary element method (BEM). The interactions among wind, wave, current, and bridge involve both aerodynamic and geometric nonlinearity. The dynamic responses of the full bridge finite element model are iteratively solved until structural convergence is achieved using the Newmark-β method. Subsequently, the buffeting responses and the vibration mechanism of bridges are discussed in both the time and frequency domains. The results indicate that the nonlinear and correlation effects of wind, waves, and currents significantly affect the buffeting responses of the example bridge. Furthermore, the influence mechanism of wind and waves on the sea-crossing bridge is also discussed.

Penerapan Bulding Information Modelling (BIM) Autodesk Revit dalam Pembuatan Bar Bending Schedule (BBS) Pondasi Pile Cap Proyek Apartemen Jkt Living Star - Jakarta Timur

Bar bending schedule is a systeem of bending patterns of reinforcement that includes data on diameter, shape, length and number of reinforcement. The purpose of this study is to obtain images of bar bending schedule documents, pile cap foundation iron volumes and find out whether Autodesk Revit software is more efficient and effective than conventional methods. This research uses quantitative methods and the manufacturing process uses the concept of Building Information Modeling (BIM) with autodesk revit software. The results showed that the use of Autodesk Revit software makes it more effective, especially in making bar bending schedule documents, because everything is made automatically. The volume of pile cap iron produced by Autodesk Revit software is 46,878 kg has a difference with the existing (conventional) volume. The volume result of autodesk revit software is less with a difference of 1.29%. This shows that Autodesk Revit software is more efficient in terms of calculating the volume of concrete iron.

Underwater Shaking-Table Investigation of Complex Deep-Water Pile-Cap Foundation for Xihoumen Rail-cum-Road Bridge

To study the mechanical characteristics of complex pile-cap foundations and the distribution law of hydrodynamic pressure acting on piles and cap in deep-water environments, the 60 m deep-water pile-cap foundation of Xihoumen rail-cum-road bridge was considered for this investigation. This paper focused on introducing the design and implementation process of simulating an earthquake using an underwater shaking-table test for a 1 : 60 complex pile-cap foundation model and systematically summarizing the test results. The test results showed that water reduced the acceleration of complex pile-cap foundation; however, the strain, displacement, and hydrodynamic pressure increased in varying degrees with water depths, and the maximum strain of the piles increased by 13.8% for the X-direction earthquake excitation and 15.1% for the Y-direction earthquake excitation in 1.0 m water-depth environment. The strain of the corner pile was the largest under earthquake excitation, followed by that of the front-row pile, and the strain of the middle pile was the smallest. When the water depth was 1.0 m, the maximum strain difference of each pile in the X- and Y-directions reached 26.4% and 27.5%, respectively. The hydrodynamic pressure acting on the piles decreased gradually from bottom to top, the edge pile bore more hydrodynamic pressure than the middle pile, and the hydrodynamic pressure difference between the piles reached 20%. Owing to the influence of the round-ended cap, the hydrodynamic pressure suddenly increased at the cap position, and the distribution law of the cap showed a gradually declining trend from front to side; however, the attenuation amplitude was affected by its shape.

Theoretical studies on dynamic impedances of symmetrically–distributed inclined piles with an elevated pile cap

Inclined pile foundations are commonly adopted in the support of wharf, harbor, bridge, and wind turbine structures. In the context of offshore wind turbines, inclined piles are typically arranged symmetrically around a circle with an elevated pile cap above sea level, referred to as an elevated pile-cap foundation. However, limited research exists on the impedances of inclined pile foundations with elevated pile caps. In this study, a theoretical model was developed that incorporates a homogeneous soil half-space and an inclined pile foundation with an elevated pile cap. The pile and soil half-space were modeled as Euler-Bernoulli beams and linear-elastic continuum, respectively. The soil’s contribution to the pile’s dynamics was represented by the receptance matrix, established at discrete interactions points along the pile’s embedded section. The effects of the rake angle and scour depth on the dynamic impedances of the inclined pile foundation with an elevated pile cap were investigated. It was observed that the peak frequency of impedance shifts to a lower value as the scour depth increases; whereas the peak frequency shifting effect is less prominent when the rake angle changes. The impedance of the elevated pile-cap foundation is more sensitive to the pile’s rake angle compared to the scour depth.

Scanning Scheme for Underwater High-Rise Pile Cap Foundation Based on Imaging Sonar

This study developed a sonar scanning scheme for underwater high-rise pile cap foundations (HRPCFs) to improve the efficiency of bridge inspection and prolong structural durability. First, two key factors in the measurement point arrangement that significantly affect the accuracy of sonar measurement—the appropriate range of measurement distance and the pitch angle—were determined experimentally. Subsequently, an assembled platform was designed to firmly hold the sonar and conveniently move it under strong currents to effectively provide clear images of the pile. A strategy was developed to determine the appropriate number and horizontal and vertical positions of the measurement points around each pile in the pile group, particularly to avoid the obstruction of signal propagation caused by adjacent piles and pile caps. The method was applied to the scanning of an underwater high-rise pile cap foundation of a bridge, and the results showed that the scanning ranges of the imaging sonar at all arranged measurement points were not affected by adjacent piles. The imaging sonar carried by the proposed platform could obtain clear images stably at a water speed of ~2.0 m/s and obtain all surface data of the pile quickly and completely.

CFD studies of the nonlinearity of NewWave group propagation and wave-structure interaction

NewWave groups are simulated using a numerical wave tank based on the CFD method. Multiple sets of NewWave groups with varying input wave amplitudes are numerically generated, and the numerical results are compared with theoretical results. The theoretical focusing time and location are backward drifting as the input wave amplitudes increase. As a result, nonlinearity should not be ignored when simulating NewWave groups for large extreme wave heights. The horizontal and vertical forces on the pile-cap foundation of a sea-crossing bridge caused by the NewWave group are investigated. Taking input amplitude A=0.06m as an example, the maximum horizontal force for a high elevated cap that is above the still water level 0.9 m is roughly twice that of a cap immersing in water 0.6 m. However, the vertical forces show less deviation. This research is primarily concerned with determining the realistic focusing location of the numerical NewWave model. Furthermore, the impact of NewWave on pile-cap foundations is studied preliminarily. It lays a solid foundation for the subsequent study of NewWave's impact on offshore structures.

Integrated Approach for Estimating Extreme Hydrodynamic Loads on Elevated Pile Cap Foundation Using Environmental Contour of Simulated Typhoon Wave, Current, and Surge Conditions

Abstract Typhoon is a disastrous weather system, which usually induces strong waves, currents, and surges along the coastal area, and causes severe hydrodynamic loads on the elevated pile cap foundation, which is widely used to support the sea-crossing bridge. Estimating the hydrodynamic loads under typhoons is essential to ensure the bridge's safety. This paper develops an environmental contour-based framework that can estimate the extreme hydrodynamic loads induced by typhoons while considering the correlation among environmental conditions. The elevated pile cap foundation of the Xihoumen Rail-cum-road Bridge was used to illustrate the framework. The SWAN + ADCIRC model was employed to simulate the environmental conditions under typhoons. The pair-copulas were adopted to construct joint probability distributions, and the environmental contours with a given return period were then established by the inverse first-order reliability method. Given the hydrodynamic model and short-term peak value of the structural response, the AK-LHS method was then used to find the maximum hydrodynamic loads based on the environmental contours. The environmental contour constructing methods and selection methods of short-term peak values were compared and discussed. The main findings include: (1) ignoring correlations of the environmental conditions overestimates the extreme hydrodynamic loads and results in a conservative design; (2) the estimation of extreme hydrodynamic loads is affected by the selection and fitting of short-term peak values significantly; and (3) the extreme hydrodynamic loads estimated by either Rosenblatt transformation or Nataf transformation shows similar results.

Lem Beton Pengaruh Penggunan Lem Beton Pada Sambungan Pengecoran Antara Beton Lama dan Baru

In carrying out concrete work, if the casting work is not completed, then the casting must be stopped at places that do not endanger the construction according to the instructions of experts in accordance with the plan drawings. Casting of joints between old and new concrete with an overview of inclination angles of 0⁰, 45⁰, and 90⁰. Joints are part of the concrete construction to provide a safe stop for the casting for the stage of construction. The casting is carried out in several steps, in the first step filling the concrete in the cylinder mold up to half of the total, after the concrete has reached the age of 7 days, then the next concrete as connection concrete fills half of the old concrete by coating the old concrete connection using glue which is a mixture of additon addibond glue + water and without concrete only a mixture of cement + water. This research was conducted so that the implementation in the field knows the function of each slope angle at 0⁰ is used in casting column connections, 45⁰ is carried out on casting plate and beam connections, and 90⁰ is carried out on casting pile cap foundation connections. The test results of the compressive strenght & split tensile strength of concrete showed that the variation of the joint slope using glue was greater than the variation of the connection without. For the results of the greatest compressive strength test in intact concrete with an average strength value of 35,29 Mpa, while in the split tensile strength test the concrete got an average strength value of 2,37 Mpa.

Integrated assessment of the hydrodynamic added mass of the deep-water pile-cap foundation considering pile group - pile cap interaction

The earthquake-induced hydrodynamic effect on the elevated pile-cap foundation is distinct from the immersed single columns or piers due to the pile group - pile cap interaction. This paper focused on the hydrodynamic added mass of the pile cap and pile group in the elevated pile-cap foundation submerged in water. The potential-based numerical model of the added mass for the integrated elevated pile-cap foundation was developed and verified with the existing solutions of added mass for the pile group. The added mass of an example deep-water elevated pile-cap foundation was calculated by the developed model, and compared with those of an isolated pile cap or pile group. The effects of pile group - pile cap interaction on seismic responses of the example foundation were quantified. It is found that the interaction can increase the added mass of the pile cap, while the interaction has a minor impact on the added mass of the pile group. Neglecting the influence of the pile group - pile cap interaction will not increase prediction errors for the structural seismic responses. The developed model allows a better understanding of the hydrodynamics of the elevated pile-cap foundation submerged in water under earthquake loading.

Structural energy transfer to the elevated pile-cap foundation of an offshore wind turbine based on extracted transfer path analysis

In the long-term operation of an offshore wind turbines (OWT), the tower bears various harmonic excitations generated by the rotation of the impeller and other environmental excitations. The energy generated by excitations will be transferred to the bottom foundation through the tower. For an elevated pile-cap foundation, different piles receive different amounts of energy, and piles that receive the largest amount of energy are more likely to move than others, making it difficult to ensure the stability of the foundation structure. In this study, the structural energy transfer to the elevated pile-cap foundation of the OWT based on extracted transfer path analysis (ETPA) is studied by considering the impeller–tower–pile structure as a source–path–receiver system. The energy transmissibility functions between the impeller and different piles of the foundation are calculated to identify the pile that bears the maximum energy from impeller rotation or other excitations. Compared with the widely applied classical transfer path analysis, the ETPA method can overcome the noise generated by OWT operation by feature extraction and yield more effective results in the case of noise. In general, the pile that bears the most energy is more likely to move compared to other piles. The calculated results can be used to assess the stability of the foundation for taking corresponding measures according to project requirements and be used for vibration-based damage detection and structural health monitoring. To study the effectiveness of the ETPA method, a four-degree-of-freedom energy transfer path theoretical model, finite element model and physical model of OWT are used to numerical study, simulation and physical experiment, respectively. Computed results of transmissibility are compared with the maximum extreme displacement of piles to verify the validity.

Damage analysis of deep water high pile cap foundations under different concrete corrosion by ship impact load

The deep-water high-pile cap foundation is in the water environment for a long time, which is likely to cause corrosion damage to the pile foundation concrete. At present, the damage analysis of the upper structure has received more attention and the technology is relatively complete, but the research on the damage identification and analysis of the substructure and foundation Relatively lacking. Due to the loading characteristics of the substructure, its own bearing characteristics and the geological watermark environment, which are quite different from the upper structure, the corresponding damage identification and damage analysis evaluation technology is quite different from that of the upper structure, so special research is needed.

Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions

Early deterioration of reinforced concrete foundations has been often reported in recent years. This process is usually characterized by an extensive mapping cracking process on concrete surfaces that results from several types of Internal Swelling Reaction (ISR). In this paper, a real case study of a tall reinforced concrete building with a severe deterioration process installed in its deep foundations is discussed. Laboratory tests were performed in concrete drilled cores extracted from a deep pile cap block 19 years after the beginning of construction. Tests to assess the compressive strength, the static and the dynamic modulus of elasticity, the gas permeability, and electron microscopy scanning to find out the primary mechanism responsible for the deterioration observed during in situ inspections. Chemical alterations of materials were observed in concrete cores, mainly due to Delayed Ettringite Formation (DEF), which significantly affected the integrity and durability of the structure. Dynamic modulus of elasticity showed to be a better indicator of damage induced by ISR in concrete than compressive strength. Procedures to strengthen the deteriorated elements using prestressing proved to be an efficient strategy to recover the structural integrity of pile caps deteriorated due to expansions due to ISR.

Influence of Cairo Metro Tunnel Excavation on Pile Deep Foundation of the Adjacent Underground Structures: Numerical Study

Day by day the call to solve traffic congestion problems is increasing. Subway tunnels and high-speed railway are commonly used for transportation. Therefore, tunnel construction induces soil movement, which in turn affects the stability and integrity of adjacent existing buildings. A series of numerical simulations have been established to investigate the effects of tunnel construction of the Greater Cairo Metro–Line 3-Phase-1 on adjacent pile cap foundations of Garage El-Attaba building. Many parameters have been investigated such as tunnel diameter and the distance between pile and tunnel at different tunnel axis and deep and shallow tunnel. After thorough analysis of the results’ simulation, it was found that the tunneling induces additional axial forces and bending moment as well as increasing axial settlement and lateral deflection. Moreover, the results obtained from the parametric study for the shallow and deep tunnel show that the tunnel depth has a much significant effect on piles responses. Finally, the tunnel diameter has an impact on pile responses as well as the pile cap foundation influenced by the tunnel when the tunnel is in very close vicinity of the pile, and its effect is modest to negligible if located far away from the buildings.

Diagnostic of Concrete Samples of Pile Caps Affected by Internal Swelling Reactions

Due to the early deterioration of pile cap foundations in residential buildings and bridges in the metropolitan region of Recife, several samples taken from a pile cap block of a residential building, built about ten years ago, were studied. The problem of the extensive cracking in the pile cap foundation had its origin in the delayed ettringite formation, possibly due to a high heat of hydration due to the concreting of the large volume of concrete. In this work, laboratory tests were performed to evaluate the transport properties of concrete samples, as well as their physical and chemical composition using advanced analyses. The tests performed in the experimental campaign were the apparent porosity, gas permeability, scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The presence of crystalline products of the alkali-aggregate reaction was proven through physical–chemical analyses, such as Raman spectroscopy and EDS. Moreover, the ettringite crystals were observed in XRD standards, SEM images and in the chemical composition of EDS. The porosity showed a high value (between 9 and 10%), as well as the concrete permeability (10–16 m2 and 10–15 m2), determining the negative influence of ISR on the transport properties. Therefore, the methods used have proven to be effective in understanding the problem encountered and have the potential to be used in the design and execution of pile cap blocks.

Role of Cap Thickness in Pile-Cap Foundation

Role of Cap Thickness in Pile-Cap Foundation

Analysis methods for pile foundation: a critical review of the literature and recommended suggestions

Pile cap foundation is a type of deep foundation. These types of foundations are used when soil, constructional or economical condition makes it necessary to transfer load of structure to the soil strata which are beyond the reach of shallow foundation. Foundation of any structures transfers the total super-structural load to soil. In case of deep foundation, the process of rehabilitation or repair is quite difficult. Hence, it should be designed properly to satisfy strength, serviceability, economic and constructability requirement. Investigation on all parameters related to these requirements is now in process, under order to develop an effective and simple approach for design of such foundations. In the present paper various methods for analysis of pile foundation are discussed in comprehensive manner. Moreover, suggestions are recommended on the basis of existing analysis methods.

Settlement analysis of pile cap with normal and under-reamed piles

The use of pile foundations has become more popular in recent years, as the combined action of the pile cap and the piles can increase the bearing capacity, reduce settlement, and the piles can be arranged so as to reduce differential deflection in the pile cap. Piles are relatively long, slender members that transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock strata having a high bearing capacity. In this study analysis of pile cap with considering different parameters like depth of the pile cap, width and breadth of the pile cap, type of piles and different types of soil which affect the behaviour of pile cap foundation is carried out by using Finite Element Software ANSYS. For understanding the settlement behaviour of pile cap foundation, parametric studies have been carried out in four types of clay by varying pile cap dimensions with two types of piles namely normal and under-reamed piles for different group of piles. Furthermore, the analysis results of settlement and stress values for the pile cap with normal and under-reamed piles are compared. From the study it can be concluded that settlement values of pile cap with under-reamed pile are less than the settlements of pile cap with normal pile. It means that the ultimate load bearing capacity of pile cap with under-reamed piles are greater than the pile cap with normal piles.

Experimental behaviour of prefabricated pile-cap foundation under seismic loading

Precast building has attracted more and more interest of both researchers and engineers due to fast constructional speed and lower labour cost. In the past, the precast structure was generally used in the superstructure, such as load bearing frame, however, it is seldom applied in the substructure such as foundation. The paper thus proposed a type of pile-cap connection to fabricate the foundation of a substation. A series of tests on the prefabricated pile-cap connection using these connections were carried out under seismic loading. The failure mode and lateral load versus lateral displacement response of the tested specimens were experimentally investigated. The seismic behaviour of the precast foundation was compared with the behaviour of the corresponding cast-in-place foundation.

Analysis of the influence of pile embedded cap depth on horizontal bearing capacity of PHC pipe pile group with cap

This paper is based on the background of the field experiment of the closed renovation project of the coal yard of Shanxi Zhangshan Power Generation Co., Ltd., and the horizontal bearing capacity experiment of the three-pile cap foundation of the in-line PHC pipe piles to be carried out on the site is used as the prototype. ABAQUS establishes an analysis model to analyze the influence of pile embedded cap depth on the horizontal bearing capacity of pile cap foundation. The results show that the maximum bending moment the pile can withstand increases as the depth of the pile embedded cap increases. Therefore, increasing the depth of the embedded cap can increase the horizontal bearing capacity of the three-pill.