Hollow Reinforced Concrete Research Articles

Finite Element Analysis of Flexural Performance of Cut Carbon Fiber Reinforced Concrete Hollow Slab

As a kind of light wall material installed on the surface of the main structure, hollow hanging wall board is widely used in prefabricated buildings. Ordinary concrete hollow board can no longer meet the needs of actual engineering. In order to study the influence of the length and content of carbon fiber on the bending performance of concrete hollow board, the optimal length and content of fiber in hollow board are determined. ABAQUS finite element software is used to simulate the whole process of concrete hollow slab with different fiber length and dosage, and the load displacement curve is analyzed. The results show that the bending performance of concrete slabs increases and then decreases with the increase of fiber length and content. When the fiber length is 10mm and the content is 0.24%, the bending performance of concrete hollow slabs is the strongest, and the ultimate load is increased by 27.90%, showing better deformation resistance under the same load.

Numerical analysis of fixed-end hollow rectangular beam under uniformly distributed load

The purpose of using opening in the reinforced concrete (RC) rectangular beam is the reduction of self-weight, cost, displacement, and strain. Therefore, this research performs linear elastic finite element analysis by using ETABS for fixed-ended RC hollow and solid rectangular beams under uniformly distributed loadings with variable beam lengths, compressive strengths, and opening sizes.The solid and hollow beams are considered to be a 2-nodded line element for the numerical analysis. The maximum range of validation result in case of hollow beam is found to be (3.9 to 7.9) %, which may indicate good accuracy of numerical analysis. The 50 × 50 mm opening size is suitable for 300 × 300 mm RC rectangular beam because of showing the positive normalized deflection of (0–1.45) % and lower strain rates (i.e. 0.13 % and 0.17 %) to compare the solid beam. This research may help professional engineers to use suitable opening size for design and construction works. Although, there is a scope to enhance this research in future by performing nonlinear analysis.

Behaviour of hollow ultra-high-performance concrete-high strength steel columns for wind turbine towers with different confinement forms subjected to combined loads

This paper investigates the behavior of circular hollow ultra-high-performance concrete (UHPC) columns reinforced with high-strength steel (HSS) tubes or reinforcements under combined loads, addressing a significant research gap in the application of UHPC for wind turbine towers. Previous studies have primarily focused on conventional towers, lacking comprehensive comparisons of the performance of UHPC columns with various HSS confinement forms such as hollow reinforced concrete (HRC), concrete-filled double-skin steel tubular (CFDST), internally confined hollow reinforced concrete (ICHRC), and externally confined hollow reinforced concrete (ECHRC). To bridge this gap, an experimental study was conducted on four different confinement forms of hollow circular UHPC columns: CFDST, ECHRC, ICHRC, and HRC. These columns were subjected to combined loads of constant compression and cyclic bending. The performance of five specimens was assessed by comparing failure modes, hysteresis curves, ultimate capacity, stiffness degradation, ductility, and energy dissipation, identifying cost-effective confinement forms. The study revealed that UHPC-HSS composite columns exhibit characteristic bending damage modes, with external steel tubes significantly enhancing their ultimate capacity and energy absorption. Replacing the internal HSS tube with reinforcements increased the load-bearing capacity by up to 5.6%. Substituting external steel tubes with steel bars leads to an 18%-27% reduction in load-bearing capacity. In terms of ductility, CFDST columns showed notable improvements, with a 2.8% increase over ECHRC column and a 7.53% increase over ICHRC column. The ECHRC column was identified as the most cost-effective, while CFDST columns, although high-performing, incurred higher costs. Finite element simulations of specimens were developed and validated the experimental results, with errors under 10%. Finally, the feasibility of predicting the ultimate strength of the columns using existing methods was evaluated based on the experimental data.

Bayesian Inference and Condition Assessment Based on the Deflection of Aging Reinforced Concrete Hollow Slab Bridges

This paper presents a Bayesian inference framework for updating the structural rigidity ratio of aging hollow slab RC bridges using deflection measurements. The framework models the structural rigidity ratio as a stochastic field along the hollow RC slabs, using the Karhunen–Loeve (KL) transform to capture spatial correlation and variation. Bayesian inference is then applied using deflection data from static loading tests, supported by a finite element model (FEM) and a Kriging surrogate model to enhance computational efficiency. The posterior distribution of the structural rigidity ratio is derived using a Markov chain Monte Carlo (MCMC) sampler. The proposed method was tested on an RC bridge with hollow slabs, using deflection measurements taken before and after reinforcement. The Bayesian updates indicated increased structural rigidity ratios after reinforcement, validating the effectiveness of the reinforcement. The deflection predictions from the updated models closely matched the measurements, with the 95% confidence bounds encompassing most of the data. This demonstrates the method’s validity and robustness in capturing the structural improvements post-reinforcement.

Experimental Study of Self-Compacting Reinforced Concrete Hollow Beams Using Recycled Aggregate under Torsion

Experimental Study of Self-Compacting Reinforced Concrete Hollow Beams Using Recycled Aggregate under Torsion

Life-cycle performance prediction and interpretation for coastal and marine RC structures: An ensemble learning framework

Long-term exposure to coastal and marine environments accelerates the aging of reinforced concrete (RC) structures, impacting their structural safety and society impact. Traditional assessments of long-term performance deterioration in RC structures involve complex, nonlinear, and time-intensive studies of physical mechanisms. While existing machine learning (ML) methods can assess the lifetime of these structures, they often prioritize data regression over mechanistic interpretation. To enhance the efficiency and interpretability of predicting the life-cycle performance of RC structures, this study introduces a generic framework based on interpretable ensemble learning (EL) methods. The framework predicts life-cycle performance efficiently and accurately, with optimal hyperparameters automatically tuned through Bayesian optimization. Interpretability algorithms clarify the influence of environmental, durability, and mechanical parameters on structural durability and mechanical predictions. Validation employs real-world cases of RC hollow beams in the coastal area of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). The comprehensive model for RC structures integrates actual data on temperature, humidity, and surface chloride content in the GBA, considering diffusion, convection, and binding effects of chloride ions, corrosion non-uniformity, and crack impact on durability estimation. Comparative analysis with existing ML methods underscores the effectiveness of the framework. The findings highlight the dynamic evolution of feature importance rankings throughout the service life, shedding light on the continuous changes in the significance of different factors when predicting mechanical resistance.

Behavior of Circular Hollow Steel-Reinforced Concrete Columns under Axial Compression

The circular hollow steel-reinforced concrete (HSRC) column consists of an inner circular hollow steel tube and outer circular hollow reinforced concrete (RC). This design provides several advantages, including being lightweight, having a wide sectional profile, and having a high flexural stiffness. This paper aims to investigate the behavior of the circular HSRC columns under axial compression through testing and finite element (FE) modeling. An FE model was established to simulate the circular HSRC columns under axial compression, which was validated against the test data. Additionally, the load distribution and the interface stress between the outer hollow RC and inner steel tube were analyzed. Subsequently, a systematic parametric analysis was conducted on the diameter (d) and thickness (t) of the steel tube; slenderness ratio (λ); strength of concrete (fcu); yield strength of steel tube (fsy), longitudinal rebar (fly), and stirrup (fgy); as well as the stirrup spacing (s). The critical influencing factors of the circular HSRC columns under axial compression were identified. fcu, λ, d, fly, and fsy dramatically influence the bearing capacity, and the stiffness is notably affected by λ and fcu. Finally, three simplified design methods were summarized and evaluated for calculating the bearing capacity of the circular HSRC columns under axial compression.

Comparative Study of Numerical Methods for Predicting Crack Propagation in Reinforced Concrete Hollow Core Slabs

Hollow core slabs are commonly used in prefabricated building construction and are calculated and constructed using gravity loads. The dead loads of the structure are reduced by using this slab system. Different criteria, such as the initiation and propagation of cracks in the hollow core slab, are used to analyze these slabs. Fracture mechanics is the basis for studying crack propagation. The present study was conducted to analyze the propagation of cracks in hollow core slabs under common loading conditions using the finite element method and numerical modeling to analyze cracks in reinforced concrete members. This research is theoretically conducted using finite element software. This research takes into account the potential varieties of cracks in concrete slabs. Slabs should consider all three types of cracks, which are shear, flexural, and flexural-shear cracks obtained from the reference test. Two Contour integral and XFEM methods are used to analyze cracks in Abaqus software. To validate and control the modeling process, the laboratory results of the research of Ibrahim N. Najma, Raid A. Daudb, and Adel A. Al-Azzawi. December 2, 2019, has been used. The outcomes of this study showed that the probability of the formation of a flexural-shear crack in the slab is higher than in other crack forms.

Flexural behavior of square concrete-encased concrete-filled double-skin steel tube members

This study presents a comprehensive investigation involving a series of experimental tests and finite element model (FEM) simulations conducted on a novel composite member subjected to bending, namely a concrete-encased concrete-filled double-skin steel tube (CECFDST) member. Comparative tests of composite performance were first conducted for a total of six specimens, including two CECFDST members, two hollow reinforced concrete (HRC) members, and two concrete-filled double-skin steel tube (CFDST) members. These tests aimed to explore the failure modes and performance of the CECFDST members under bending. The findings revealed that the CECFDST specimens exhibited good stiffness and bearing behavior, showcasing good cooperation between the components. Notably, they achieved a bearing capacity 8.1% higher than the combined value of the HRC and CFDST specimens. Then, an FEM was developed to analyze the flexural performance of CECFDST members, including the stress and constraint mechanisms, and its accuracy was verified. Furthermore, a systematic parametric analysis was carried out using the verified FEM to identify the key parameters influencing the bending performance and the composite effect. Finally, a simplified calculation method was developed to predict the flexural capacity of CECFDST members.

Numerical analysis of high-strength centrifugal precast RC hollow pipe columns using grouted corrugated duct connection: Confinement effect and ductility evaluation

High-strength centrifugal precast (HSCP) reinforced concrete (RC) hollow pipe columns using grouted corrugated duct connection (GCDC) is a novel structure form in accelerated bridge construction (ABC). Nevertheless, the confinement effect of the HSCP hollow column core concrete provided by single-layer transverse rebar and its impact on ductility is not clear. Therefore, in this paper, the confinement effect and the ductility of hollow columns is studied using finite element analysis (FEA) method. A modified model is established to evaluate the constitutive relation of the core concrete confined by single layer transverse rebar. Based on the modified model, a simplified fiber model for predicting the hysteric response of HSCP hollow pipe column using GCDC, which considers bond-slip effect in GCDC joint was developed. The results indicate that the confinement effect of HSCP hollow pipe column is sensitive to the wall thickness ratio. When the wall thickness ratio decreases, the ultimate strain of the core concrete significantly decreases, while the effect on strength is not significant. The simplified model which considers confinement effect is more accurate in predicting the ductility of HSCP hollow columns. It proves that the weak confinement effects can lead to early cracking of the inner wall of hollow columns, which leads a significant impact on the ductility of HSCP hollow columns. Based on the parametric analysis, the peak load of the hollow column increases by 16.7% when the wall thickness ratio rises from 0.1 to 0.2, but only slightly changes when the wall thickness ratio is increased beyond 0.2. The wall thickness ratio of HSCP hollow pipe columns should be set above 0.2 to ensure the strength and ductility. In addition, a ductility evaluation method and a design example were developed to guide preliminary ductile design of HSCP hollow columns.

Residual performance of hollow RC piers damaged by rockfall impact

Recently, hollow reinforced concrete (RC) piers have been increasingly utilized in bridge structures located in mountainous regions, owing to their high strength-to-mass ratio and stiffness-to-mass ratio. Among various natural disasters, rockfall poses a major threat to the serviceability and safety of bridge piers, potentially leading to a reduction in bearing capacity or even complete collapse. Given the critical nature of repairing or reinforcing bridges, this paper aims to enhance the understanding of the residual performance of hollow RC piers against rockfall impact. A simulation framework for hollow piers subjected to rockfall impact is developed using LS-DYNA and validated against available experimental data. Utilizing this validated framework, extensive numerical simulations have been conducted to investigate the effect of various parameters such as impact energy, longitudinal reinforcement ratio, stirrup ratio, and axial force ratio on the localized damage patterns and residual capacity of hollow piers. In addition, the relationship between the rupture width of the front panel and the resulting reduction in axial capacity is discussed. These results indicate the impact force and resistance mechanism of hollow piers are governed by the interaction between the rockfall and hollow section. The rupture width of the front panel notably increases with the impact energy, and increasing the stirrup ratio could reduce the concrete spalling. However, the axial force demonstrates minimal influence on the localized damage of the front panel when the rockfall diameter is less than the front panel width. The residual capacity of an impact-damaged hollow pier mainly relies on the rupture width of the front panel. These findings would contribute to the fast prediction of the residual capacity of hollow RC piers after rockfall impact.

Failure Mode Identification and Shear Strength Prediction of Rectangular Hollow RC Columns Using Novel Hybrid Machine Learning Models

Failure mode identification and shear strength prediction are critical issues in designing reinforced concrete (RC) structures. Nevertheless, specific guidelines for identifying the failure modes and for accurate predictions of the shear strength of rectangular hollow RC columns are not provided in design codes. This study develops hybrid machine learning (ML) models to accurately identify the failure modes and precisely predict the shear strength of rectangular hollow RC columns. For this purpose, 121 experimental results of such columns are collected from the literature. Eight widely used ML models are employed to identify the failure modes and predict the shear strength of the column. The moth-flame optimization (MFO) algorithm and five-fold cross-validation are utilized to fine-tune the hyperparameters of the ML models. Additionally, seven empirical formulas are adopted to evaluate the performance of regression ML models in predicting the shear strength. The results reveal that the hybrid MFO-extreme gradient boosting (XGB) model outperforms others in both classifying the failure modes (accuracy of 93%) and predicting the shear strength (R2 = 0.996) of hollow RC columns. Additionally, the results indicate that the MFO-XGB model is more accurate than the empirical models for shear strength prediction. Moreover, the effect of input parameters on the failure modes and shear strength is investigated using the Shapley Additive exPlanations method. Finally, an efficient web application is developed for users who want to use the results of this study or update a new dataset.

Flexural behaviour of hollow reinforced concrete T-beams strengthened or retrofitted with carbon-fibre-reinforced laminates: Experimental and numerical investigation

This study investigates the effect of longitudinal rectangular openings on the flexural behaviour of reinforced concrete (RC) T-beams strengthened or retrofitted with external carbon-fibre-reinforced polymer (CFRP) laminates. Eight RC T-beams, with one solid and one hollow beam in each of four groups, were analysed using a three-point bending test. The CFRP laminate used in each beam was similar, and the beams had an identical longitudinal reinforcement ratio. The ultimate load capacity of the strengthened hollow RC T-beams showed a 9% decrease compared to that of the strengthened solid RC T-beams, while retrofitted hollow RC T-beams with 100% preloading exhibited a 24% decrease in ultimate load capacity compared to that of retrofitted solid RC T-beams. In addition, the CFRP laminate had a positive effect on reducing strain in hollow RC T-beams as compared to that of solid RC T-beams. The flexural behaviour of the CFRP-strengthened hollow RC T-beams with a 5% cross-sectional hollow core area was similar to that of strengthened solid RC T-beams. However, after preloading, the retrofitted hollow RC T-beams exhibited a decrease in flexural efficiency compared to the retrofitted solid beams. A validated numerical model was developed using ABAQUS to accurately simulate the behaviour of the hollow RC T-beams. Subsequently, a parametric study was conducted using the validated model to investigate the effects of varying the position and size of the hollow section on the response of the RC T-beams.

Shear Capacity of Hollow Reinforced Concrete Members without Stirrups

This paper presents experimental results on the shear capacity of hollow reinforced concrete members without stirrups. The area of the hollow was 2.32% of the concrete cross-sectional area. The hollow size used in this study is smaller than the maximum percentage required in the code, where the maximum hollow area was 4% of the total cross-sectional area. The longitudinal reinforcement used in the specimen varies with the three types of reinforcement ratios. The test was carried out using the four-point shear test to achieve the expected shear failure mode. The loading was given monotonically until the specimen failed. Analytical flexural capacity was also calculated using the fiber element method. The specimens failed in shear failure mode, indicated by large diagonal cracks in the observed shear span. The influence of the hollow on the shear strength was also compared with the theoretical shear capacity proposed by the code. This comparison shows that the calculated theoretical shear capacity is conservative for hollow reinforced concrete structural elements with a hollow area smaller than 4%. The results of the flexural analysis show that all the specimens did not reach the flexural capacity due to premature shear failure.

Multifractal characteristics of fatigue cracks in the full-scale reinforced concrete hollow-slab beams

Highway Reinforced concrete (RC) bridges bear the repeated vehicle loads for a long time, promoting cracks' sprouting and development. Establishing a quantitative evolution model of cracks will improve the management and maintenance of similar bridges. Therefore, this paper introduces the multifractal theory into crack characterization and carries out the study on the multifractal characteristics of fatigue cracks in full-scale RC hollow slabs. Firstly, the basic procedure of the multifractal analysis method for concrete cracks is introduced, and the sensitivity of the multifractal spectrum under different influencing factors is analyzed. Secondly, the basic information and scheme of the experimental beam are introduced. The experimental results and the development law of fatigue cracks are analyzed. Finally, the variation law of the multifractal spectrum with cycle number is analyzed based on the multifractal theory, and a simplified evolution model of fractal dimension (FD) under fatigue load is established based on the experimental results. The experimental results prove that the multifractal theory is effective in describing the cracking state of RC members under fatigue load. The fatigue cracks' development of the experimental beam presents an obvious three-stage pattern: rapid stage, stable stage, and destabilized stage. The FDs of fatigue cracks also develop in a three-stage pattern along with cycle number, which can be expressed by a linear equation of cycle percentage. The evolution model can provide technical support for the maintenance decisions of RC bridges in service.

Experimental study on flexural behaviours of fresh or aged hollow reinforced concrete girders strengthened by prestressed CFRP plates

The paper presents a well-rounded experimental study on the flexural performance of Reinforced Concrete (RC) box girders strengthened with prestressed carbon fibre reinforced polymer (CFRP) plates. The motivation behind the study was twofold: the rising need for structural reinforcement of existing aged and heavily utilised hollow RC box girders, and the absence of prior attempts to integrate prestressed CFRP plate strengthening for those hollow girders. Previous experimental studies are scarce and fewer studies are focused on the combined prestress and thin-wall effects, such as prestress-related stress condensation and shear lag. However, experimental results are important in directing further analytical studies for hollow sections with more complex behaviours than solid sections since there is a need to predict the behaviour of the prestress-strengthened hollow RC structures for routine design. This pivotal experimental study aims to quantify the structural interactions initiated by prestress in hollow sections and evaluate the impact of age while promoting further analytical initiatives. In this study, two types of CFRP plates, ordinary CFRP and steel-wire-CFRP (SW-CFRP), were used on different specimen beams with varying prestressing levels, sizes of the CFRP plates, and pre-damaged states representing aged and over-used members. Their performance indexes, including cracking load, yield load, ultimate load, structural stiffness, ductility, and crack resistance, were tested and summarised in this paper. The CFRP plates of the eight specimen beams were prestressed to different levels (non-prestressed, and 30% and 40% of the CFRP plate's ultimate strength). The test results suggest that the crack load increased by 86% and 134%, when the specimens were enhanced with the combinations of 30% prestress level for the same CFRP cross-section, and 40% prestress level with a thicker CFRP plate, respectively. The flexural capacity also increased by 42% and 72%, and flexural stiffness increased by 3% and 63%, respectively. The experimental results proved that the proposed prestressed CFRP plate technology effectively strengthens the new or aged RC box girders, but the ductility is sacrificed. These first-hand test results provide an excellent target dataset for further development in the analysis and design of prestressed CFRP plate-strengthened RC box girders.

Structural Behavior of Reinforced Concrete Hollow Core Slabs Cast with Self-Compacting Concrete Containing Recycled Concrete as Coarse Aggregate

This paper investigates the possibility of recycled aggregate use in concrete slabs with hollow cores. The main variables considered in the experimental study for the slabs were the recycled aggregate percentage and the hollow core number. Six slabs with dimensions of (1000 × 500 × 120) mm was fabricated and tested. The results showed that the addition of recycled aggregate in the concrete slabs affected the ultimate strength, ductility, and energy absorption of the concrete members. An increase of the recycled aggregate percentage to 25 % decreased the ultimate strength capacity by 3.54 %, but the increase of recycled aggregate to 50 % led to a decrease in the ultimate strength of about 6.64%. The existence of a hollow core reduced the cracking and ultimate load capacity of the RCA slabs, and this reduction was according to the core number which the fabrication of more cores caused more decrement. The ductility and energy absorption were decreased when the replacement ratio of the recycled aggregate increased. Also, the core number affected the ductility and energy absorption. The energy absorption was the most property affected by the core number increase which caused an average reduction of 71.5 % when the core number increased from two to three hollow cores.

Structural Behavior of Reinforced Concrete Hollow Beams under Partial Uniformly Distributed Load

A Longitudinal opening is used to construct hollow core beam is a cast in site or precast or pre stressed concrete member with continuous voids provided to reduce weight, cost and, as a side benefit, to use for concealed electrical or mechanical runs. Primarily is used as floor beams or roof deck systems. This study investigate the behavior of six beams (solid or with opening) of dimension (length 1000 x height 180 x width120mm) simply support under partial uniformly distributed load, four of these beam contain long opening of varied section (40x40mm) or (80x40mm). The effect of vertical steel reinforcing, opening size and orientations are investigated to evaluate the response of beams. The experimental behavior based on load-deflection measured at central and quarter of tension zones. The experimental test result shows the presence of Hollow decrease the load carrying capacity by about (37.14% to 58.33%) and increased the deflections by about (71.6% for (Hollow ratio 7.4%) to 75.5% for (Hollow ratio 14.8%)) for same applied loadcompared with solid beams with the same properties. The increase shear steel reinforcing will decrease all the deformations at all stages of loading, but particularly after initial cracking and give enhancement in ultimate load capacity of beams by about 31.5% with increasing the amount of shear steel reinforcing by about 50%. Finally, ductility is increased in all cases under partial uniformly distributed load when hollow ratio decreased by about 50% or increased in shear steel reinforcing by about 50%

Experimental investigation on plastic hinge length of RC round-ended hollow columns with a variable section

In the ductile design, it is an essential task to accurately estimate the equivalent plastic hinge length of a reinforced concrete (RC) column. The plastic behavior of a RC hollow column is influenced significantly by tension shift and bond-slip according to the test results, which hasn’t yet received adequate attention in the existing models of equivalent plastic hinge in the literatures. Few publications and even no explicit provision in the current codes provide the method to compute the plastic hinge of hollow RC columns, especially those with a variable section. To bridge this knowledge gap, in this study, based on the equivalent principle of plastic displacement, an innovative formula of equivalent plastic hinge length is derived for the hollow columns, which considers both the effects of plastic tension shift and bond-slip based upon the authors’ previous research on solid columns. The quasi-static tests on two rectangular and two round-ended hollow columns were conducted to calibrate the undetermined parameters of the proposed formula. The accuracy and applicability of the proposed formula were then investigated based on the available test results of 30 rectangular and 3 round-ended hollow columns in literature. The results show that different slip behavior leads to distinct plastic deformation between these two types of hollow columns. Compared to the rectangular columns with a uniform section, the plastic hinge length of round-ended columns is longer due to the presence of the bottom solid segment, chamfer, and variable section. For both types of hollow columns, the equivalent plastic hinge region increases with the specimen length, section height, and strain penetration. The comparison suggests that the proposed formula is more appropriate to calculate the plastic hinge length of hollow columns with a uniform or variable section than the existing models.

Dynamic responses and damage behavior of hollow RC piers against rockfall impact

Rockfall impact on bridge piers poses a challenge to the safety of bridge structures in mountainous regions. Hollow reinforced concrete (RC) piers are one of the popular constructional elements in engineering construction, and their impact behavior has not been fully investigated. Therefore, this study aims to explore the dynamic responses and damage behavior of hollow RC piers under rockfall impact. A finite element (FE) model of a hollow RC pier is established and validated against experimental tests. The validated model is then utilized to investigate the impact force, lateral displacement, internal forces, and failure mode of the hollow pier under rockfall impact. A parametric study is conducted to examine the effectiveness of rockfall diameter, impact velocity, axial force, impact elevation, and reinforcement ratio on the dynamic responses and damage modes of hollow piers. The results show that hollow piers under rockfall impact are prone to suffer serious localized damage with concrete spalling at the front panel, which plays a significant role in the pier’s global response. The stress distribution of cross-sections near the impact position is governed by the stress wave propagation and sectional internal force. Increasing the rockfall diameter would change the resistance mechanism of the front panel and enlarge the peak impact force (PIF) due to the influences of side panels and impact energy. The effects of impact elevation, axial force ratio, and reinforcement ratio are marginal on the impact force but significant on the lateral displacement and damage of hollow piers. This study provides a comprehensive understanding of impact performance of hollow RC piers and offers useful insights for their design and protection against rockfall hazards.