Precast Concrete Pipe Research Articles

Seismic Deformation Analysis of Precast Concrete Pipe Hybrid Based on 3D LiDAR and Unmanned Aerial Vehicle Photogrammetry

Seismic Deformation Analysis of Precast Concrete Pipe Hybrid Based on 3D LiDAR and Unmanned Aerial Vehicle Photogrammetry

Mechanical Properties of Precast Concrete Pipe (PCP) Sheet Under Different Curing Conditions and Ages

Mechanical Properties of Precast Concrete Pipe (PCP) Sheet Under Different Curing Conditions and Ages

Analytical solution for the horizontal dynamic response of strength composite piles in fractional viscoelastic unsaturated ground

The analytical representation of the dynamic interaction between a strength composite (SC) pile and unsaturated soil under lateral excitations at the pile head is studied using three-dimensional continuum modelling. The fractional standard line solid (FSLS) model is utilized in the governing equation of unsaturated soil to characterize the flow-independent viscosity of the soil skeleton. Timoshenko beam theory is employed to describe the horizontal dynamic behaviour of SC piles composed of cement-soil mixing (CM) piles and precast high-strength concrete (PHC) pipe piles. A closed series form solution of the horizontal dynamic behaviour for an SC pile embedded in unsaturated soil under lateral excitation at the pile head is deduced theoretically. The solutions of the proposed model are compared with those captured from existing solutions. Finally, the effects of physical parameters in the SC pile-unsaturated soil system on the horizontal dynamic behaviour of the SC pile are evaluated with analytical examples and parametric study. The results indicate that the radius and elastic modulus of the SC pile have a critical influence on the horizontal dynamic behaviour of the SC pile, the FSLS model parameters are the key factors influencing the horizontal dynamic behaviour of the SC pile, and the horizontal dynamic behaviour of the SC pile varies with the change in liquid saturation of unsaturated soil. The research results provide theoretical references for the anti-vibration design and safe operation of SC piles.

Investigation of Backfill Compaction Effect on Buried Concrete Pipes

The present study deals with the experimental investigation of buried concrete pipes. Concrete pipes are buried in loose and dense conditions of gravelly sand soil and subjected to different surface loadings to study the effects of the backfill compaction on the pipe. The experimental investigation was accomplished using full-scale precast unreinforced concrete pipes with 300 mm internal diameter tested in a laboratory soil box test facility set up for this study. Two loading platforms are used namely, uniform loading platform and patch loading platform. The wheel load was simulated through patch loading platform which have dimensions of 254 mm *508 mm, which is used by AASHTO to model the wheel load of a HS20 truck. The pipe-soil systems were loaded up to pipes collapse. Pipes were instrumented with strain gauges to measure circumferential strains, in addition to dial gauges, for measurements of the pipe vertical deflections and settlement of the loading platforms. The test results indicated that flexure governed the buried pipe behavior. Flexural cracks formed slightly before the ultimate load. A comparison of soil backfill, between a loose and dense compaction, showed that the dense backfill improve largely the pipe installation and the strength ofpipe-soil system

Predicting the performance of existing pre-cast concrete pipes using destructive and non-destructive testing techniques

One of the most significant and critical urban assets for a sustainable community is the sewer pipeline network and water distribution system. Water sewer networks and distribution systems have a definite service life span to provide continuous facilities to end users. Therefore, it is pertinent to continuously evaluate the condition of water and sewer concrete pipelines to ensure the reliable, sustainable, and cost-efficient transport of water and sewerage for the safety of society. The condition assessment is commonly carried out by visual observations followed by some non-destructive testing methods. However, it is the need of the hour to shift assessment methods to advance assessment techniques to save time and money for our community. Currently, in this project, the condition assessment of pre-cast concrete pipes was carried out by destructive and non-destructive methods. Different test trials i.e., ultra-sonic pulse velocity, Schmidt hammer also known as rebound hammer test, visual inspection, three edge bearing test, and core cutting test on the old buried and new concrete pipes were performed. It was observed that concrete used for the construction of existing precast concrete pipes still has better quality indices after 20 years as compared to that of concrete of new pipes. However, steel has deteriorated with time and clear corrosion of steel was identified in existing pre-cast concrete pipes. At the same time, it was observed that there should be an automated mechanism to continuously asses the condition of pre-cast existing pipes which will address the sustainable development goals (SDG 6, 9, 11). Consequently, it can be said that condition assessment of pre-cast concrete pipes will lead to sustainable societies and infrastructure.

Development of Concrete Mixture for Spun-Cast Full-Scale Precast Concrete Pipes Incorporating Bundled Steel and Polypropylene Fibers.

Spin casting is the oldest method of manufacturing precast concrete pipes among all existing methods. While improved concrete mixtures incorporating fibers for other methods of concrete pipe manufacturing, such as the vibration method and roller compaction method, have been developed, no such concrete mixture has yet been developed for spun-cast concrete pipes. This study was designed to explore the possibility of incorporating locally manufactured steel fibers and commercially available polypropylene fibers to develop an improved concrete mixture for use in the manufacturing of full-scale spun-cast concrete pipes. The used steel fibers were of two types, i.e., straight and bundled steel fibers, manufactured by cutting locally available long straight and bundled steel wires, respectively. Various dosages of steel fibers (i.e., 20, 30, 40, and 50 kg/m3) and polypropylene fibers (i.e., 5, 10, 15, and 20 kg/m3) were used in mono and hybrid (steel and polypropylene) forms. The properties in the fresh state and mechanical properties of the test mixtures were investigated. Full-scale spun-cast concrete pipes having a 450 mm internal diameter were manufactured and tested using the three-edge bearing test. The compressive strength of the mixtures was largely insensitive to the dosage of the fibers. The splitting tensile strength of all fiber-reinforced concrete mixtures was higher than that of the reference mixture without fibers, with a 24% increase recorded for the concrete mixture incorporating 50 kg/m3 of bundled steel fibers relative to the reference mixture with no fibers. The flexural performance of the fiber-reinforced concrete mixtures was superior to that of the reference mixture without fibers in terms of flexural strength, toughness, residual strength, and crack control, with up to 28% higher flexural strength relative to the reference mixture without fibers. The three-edge bearing tests on full-scale spun-cast pipes incorporating steel fibers showed that the use of fibers is a promising alternative to the traditional steel cage in spun-cast concrete pipes.

Experimental fire performance assessment of a new type of prestressed composite circular precast concrete columns

The purpose of this paper is to study the fire resistance of a new type of prestressed composite circular precast concrete column (PCCPCC) consisting of a prestressed precast concrete hollow pipe and cast-in-place core concrete filled in the hollow section through a combined numerical and experimental approach. The potential advantages of PCCPCCs lie in their low manufacturing costs and high construction efficiency. A series of fire tests were conducted on PCCPCCs with consideration of different precast concrete strengths, rebar layouts, and axial loads, where the column damage patterns, fire exposure time, and vertical displacements of all the specimens were experimentally examined. Their post-fire residual strengths were also determined via uniaxial compression tests. Finite element (FE) simulations were also conducted and the obtained results were compared to the corresponding test outcomes. The results show that the fire resistance of PCCPCCs is largely dependent on the imposed axial loading, and an effective thermal isolation effect from the prestressed precast concrete hollow pipes was identified. The further research on this new column form is necessary for the possible future wide adoption.

Heavy Metal Pollution Levels of Hand-dug Wells in Close Proximity to Septic Tanks

The aim of this study is to evaluate the levels of selected heavy metal contamination in well water located in close proximity to septic tanks in the South gate area of the Federal University of Technology, Akure (FUTA). Water samples were collected from five (5) randomly selected hand-dug wells in the study area within 50ft (15.4m) distance to septic tanks. The physical attributes of the wells revealed that the wells were well constructed and all the wells sampled were lined with precast concrete pipe (PCP) rings with covers. Five heavy metals namely Cadmium (Cd), Chromium (Cr), Iron (Fe), Manganese (Mn) and Zinc (Zn) were analyzed in the laboratory using Atomic Absorption Spectroscopy. Cd, Cr and Mn were present in high concentration in some of the water samples evaluated exceeding the WHO permissible limit. However, Fe and Zn contents of the water fell within WHO standard for potable water. Secondary water treatment is recommended before human consumption. Keywords— heavy metals, potable, septic tanks, treatment, water samples.

Basic Installations for Reinforced Concrete Arch Pipe

Beginning in 2018, the precast concrete pipe producers of the Minnesota Concrete Pipe Association (CPA) worked with the Minnesota Department of Transportation (DOT) to update the standards for reinforced concrete arch pipe. The Minnesota DOT standard plates include steel reinforcement areas for both circumferential steel and transverse steel (stirrups) where required. The latest Minnesota DOT standards include pipe classes in accordance with AASHTO M206 (or ASTM C506) as well as some larger sizes and higher strength classes that are not included in the AASHTO standard. The reinforcement designs for these larger sizes were performed in accordance with the 8th Edition of the AASHTO LRFD Bridge Design Specifications and were formulated to encompass the worst of either the loads from the field installation, or the testing loads in three-edge bearing. The three-edge bearing test requirements tended to govern the required steel area for transverse reinforcement. However, the field conditions governed the extent to which the transverse reinforcement needs to extend out from the invert of the pipe.

Numerical Study on the Applicability of the Pipe-Jacking Method for the Main Gate of an Underground Coal Mining in Weak Rock Mass

The typical reinforcements and supports used in the main gate of underground coal mining (particularly in the weak to very weak rock strata), such as rock/cable bolts, steel sets, and grouting materials, often allow the mine to remain serviceable in the long run, but in complicated geotechnical and geological conditions, they are insufficient. Low rock strength leads to instability and exhibits serious ground control issues. The pipe-jacking method with a precast concrete pipe support can be one of the more appropriate options for significantly improving geotechnical concerns. This paper aims to study the applicability of pipe-jacking technology in underground coal mining based on a series of numerical analyses employing a three-dimensional FEM (3D-σ software, Geoscience Research Laboratory Co Ltd, Kanagawa, Japan). In the numerical analyses, we study the crown deformation and failure proximity using different inclination angles for the tunnel, different highwall slopes, and two different shapes for the pipe. It is important to note that a precast concrete pipe is effective as a primary support system and can improve the stability of the main gate efficiently.

UJI MODEL FISIK RAYAPAN GELOMBANG PADA REVETMEN BUIS BETON

Buis Beton (Precast concrete pipe) revetment is a common coastal structure to protect the shoreline from erosion. However, it is common that this type of structure face high wave run up. A continuous wave run up on the slope of the structure may reduce the life service of Buis Beton revetment. The objective of this research is to create scientific based guidance to design an efficient Buis Beton revetment against wave run up. A physical modelling test is conducted to understand the relationship between wave run up and Buis Beton revetment. The test scenario is based on the slope of the structure (θ), structure height (L), buis beton diameter (φ), incoming wave height (Hi) and wave period (T). The physical modelling is conducted in 2D wave flume with laboratory scale of 1:10 with regular wave simulation. Wave run up is observed using a video camera which is later processed digitally to acquire the wave run up data. This research shows that the relative wave run up has a reciprocal functional relationship with the Iribarren Number parameter. In general, wave run up height on Buis Beton revetment is less than or equal to 2.64 the wave height, Hm0.Keywords: Revetment, buis beton, wave run-up, physical modelling

Effect of Bedding Compaction on the Behavior of Buried Plain Concrete Pipes

Plain Concrete pipes serve as effective underground infrastructure lines especially as sewer lines and culverts. The installation quality has a high effect on the performance of the buried pipe-soil system besides the pipe material strength. In this research, experimental investigation of buried plain concrete pipes installed in gravelly-sand soil and subjected to strip loading platform as surface loading to search the effect of the bedding compaction on the pipe. Granular soil bedding is a traditional material surrounding concrete pipes. An experimental testing program for two precast plain concrete pipes has 300 mm inner diameter was conducted in a laboratory soil box test facility. Loading on a pipes-soil system were applied up to collapse. Circumferential strain in pipes was measured by means of strain gauges in addition to the measurements of displacement developed in the vertical direction by means of a linear variable differential transformer (LVDT’s) and dials gauges. It is concluded that in case of loose bedding, a higher bedding factor of 1.83 is produced in comparison with dense bedding which produces a bedding factor of 1.49, thus yields that the quality of installation is improved with relatively loose bedding under the pipe.

Modeling structural behavior of precast concrete pipe with single elliptical steel cage reinforcement

Using single elliptical (SE) cage reinforcement in reinforced concrete pipes (RCP) can reduce both the needed reinforcing steel and labor for manufacturing double and triple steel reinforcing cages. However, there is currently no robust tools to predict the structural behavior of RCP with SE reinforcement. In this study, non-linear 3D finite element model was developed to evaluate the load capacity of SE reinforced RCP. Model predictions were validated using experimental results on corresponding full-scale pipes. The model simulated load–deflection curves of RCP under the three-edge bearing test (TEBT) and predicted its load capacity with an average error of 9%. A parametric study was conducted to investigate the effects of SE cage rotation on the load capacity of RCP. It was found that rotation had minimal effect on the elastic behavior and stiffness of the pipe up to 1 mm vertical deflection. However, SE cage rotation had greater significance on the plastic response of the pipe when the steel reinforcement became fully engaged. The proposed model could provide a basis for developing design charts for RCP with SE reinforcement and quantify possible effects of SE reinforcing cage rotation on pipe load capacity.

Investigation of structural behavior of precast concrete pipe with single elliptical steel cage reinforcement

Reinforced Concrete Pipe (RCP) with single elliptical (SE) reinforcement offers cost savings and is permitted by Canadian and American standards. Yet, its use has not yet gained momentum primarily due to limited knowledge of its structural performance. This study explores the structural behavior of full-scale 1050 mm and 1200 mm diameter RCP reinforced with SE cold drawn steel wire cage under the three-edge bearing test. Experimental results show that, given similar amount of reinforcing steel at the tension zone of the inner face of the invert and obvert of the pipe, RCP with SE reinforcing cage meets lower equivalent class than that of RCP with conventional double reinforcing cage. The absence of a second layer of reinforcement in the SE pipes produced more brittle failure characterized by radial tension, followed by concrete slabbing. Increasing the steel reinforcement ratio improved the 0.3-mm crack load and ultimate load capacity up to a certain threshold, beyond which adding more steel did not enhance the results. Results indicate that RCP with SE reinforcement designed per current standards did not meet the specified 0.3-mm crack and ultimate load capacity. Hence, pertinent provisions in CSA A257.2 and ASTM C76 for RCP need to be updated with specific and more suitable guidance for single elliptical cage RCP.

Investigation on the thermal response of full-scale PHC energy pile and ground temperature in multi-layer strata

A thermal response test (TRT) was conducted on a full-scale precast high strength concrete (PHC) pipe pile installed in multi-layered ground, in order to investigate the thermal response of the pile and soils in inhomogeneous ground. The thermal properties of each layer were tested in the laboratory and compared to the estimation from the TRT. The ground temperature evolution was monitored using 4 boreholes around the pile, and the pile temperature distribution was captured from transducers prefabricated in the pile wall. The system thermal conductivity estimated from TRT results was 2.11 W/(m K) which is about 2 times that from the lab test (1.15–1.71 W/(m K)). The comparison with other TRTs suggests that fitting time and heating power may influence the estimated results. The ground temperature response varied along the depth. Comparing the layers, more conductive soil was cooler near the pile but warmer at a distance. Up to 23% difference of temperature increment (1.1 °C) was found. The pile temperature was less influenced by soil stratification but was evidently affected by end effects, which caused a maximum difference of 16% (3.2 °C) from the average temperature increment. The average ground and pile temperature increased by 1.1 °C and 1.5 °C respectively at 37 days after heating. This suggests that an accumulated temperature increase could happen in a cooling-dominated district.

EXCITATION AND DYNAMIC RESPONSES OF JACKET STRUCTURES IN REGULAR WAVES FOR OFFSHORE INSTALLATION

The world’s energy supply needs to scope two aims: Securing an ongoing growth in energy demand while gradually shifting to exploitation of renewable energy resources. Since onshore and near shore areas to harvest energy from wind are running short, the focus is laid on concepts for deep water regions ranging from 30 up to 50m with over 6MW. The presented work is a part of the research project HyConCast which progresses the development of a novel, hybrid support structure for offshore wind turbines. Thereby the concept addresses to develop and deploy hybrid offshore wind farm support structures which are based on the advantages of combined ductile iron casting knots and precast concrete pipes. The overall objective of the project is to assess the feasibility and general applicability under design load cases stemming from environmental, eco-logical and economical dimensions. With respect to the distinctly higher total weight of the hybrid structure compared to common steal structures, the results of its so far not understood excitation and dynamic motion response in regular waves during floating installation are researched and discussed in the following article.

Rational finite element assisted design of precast steel fibre reinforced concrete pipes

There has been growing interest to introduce steel fibres in precast concrete pipes as a replacement for regular reinforcement. Several experimental studies have been conducted in order to determine the optimal fibre content for various pipe design scenarios. However, there is still need for more inclusive and comprehensible design approaches. This paper aims at developing a rational design tool for precast SFRC pipes. For this purpose, a non-linear 3D finite element model was developed to simulate the three-edge-bearing test. The model was verified using experimental data generated previously by the authors on full-scale SFRC pipes as well as other data available in the open literature. The model was capable of reasonably simulating the load-deformation curves of SFRC pipes tested using the three-edge-bearing method. The average error in model-predicted ultimate D-loads was about 6.5% on the conservative side. Subsequently, a parametric study was conducted. The pipe diameter, pipe wall thickness, fibre type and content, concrete compressive strength, and targeted pipe strength were the parameters under investigation. The findings of the parametric study were presented in a tabular form that can be used as a design aid supplementary to the ASTM C1765 standard.

Mechanical performance of full-scale precast steel fibre-reinforced concrete pipes

This paper reports the findings of a laboratory-testing program performed on full-scale precast concrete pipes reinforced with dispersed steel fibres. Steel fibre reinforced concrete (SFRC) pipes had diameters of 450 and 600mm. Two types of steel fibres having round cross-sections and hooked ends were used. Steel fibres had lengths and aspect ratios of 35 and 60mm, and 65 and 80, respectively. The steel fibres content ranged from 0 to 40kg/m3. Plain (PC) and conventionally reinforced (RC) precast concrete pipes were also tested for comparison. Tested specimens were instrumented with strain gauges mounted on critical sections of each pipe. In addition, vertical and horizontal deformations of the pipe’s cross-section were monitored using LVDTs. Precast pipes were tested using both the continuous and cyclic loading procedures as per the ASTM C497 and EN 1916 guidelines, respectively. Results showed that a fibre dosage of 30kg/m3 satisfied the strength requirements of ASTM C76 Class V pipe for 450 and 600mm diameter pipes. In addition, the post-peak behaviour of SFRC pipes was comparable or superior to that of conventional RC pipes at small deformations. It was also found that the behaviour of SFRC pipes could be fully explored using the continuous three-edge-bearing test without need of an extra loading cycle as specified in the EN 1916 standard.

Full-scale pipes using dry-cast steel fibre-reinforced concrete

The mechanical properties of dry-cast steel fibre-reinforced concrete (DCSFRC) were investigated in the present study. Four commercially available steel fibres were added at rates of 0, 20, 40 and 60kg/m3. Full-scale 300mm diameter precast pipes were fabricated using the tested DCSFRC mixtures to examine its potential for such application. In addition, plain (PC) and conventionally reinforced concrete (RC) precast pipes were fabricated and tested for comparison. As expected, results showed that the mechanical properties of DCSFRC were enhanced as the fibre dosage increased. Generally, hooked-end fibres with the highest aspect ratio led to highest tensile and flexural strengths. Furthermore, DCSFRC precast pipes achieved ultimate loads greater than the required strength for Class V pipes according to the ASTM C76 standard. The post-peak behaviour of DCSFRC pipes was comparable or superior to that of conventional RC pipes. Findings of this research indicate that discrete steel fibres could be an adequate alternative to the labour intensive and time-consuming steel cages normally used for reinforcing precast concrete pipes.

Finite Element Analysis of the Experiment of PC Pipe Pile with Holes Carrying Capacity

To study the carrying capacity of precast concrete pipe pile (PC pipe pile)with holes, the ABAQUS finite element software is used to simulate the experiment of the PC pipe pile with holes carrying capacity from different holes arrayments.The results showed that the strength of the PC pipe pile decreased after the area of holes increased.With the same area of holes,the increase in diameter of holes caused the strength decreased. Guidance would be given for the permeable PC pipe pile by the paper.