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Abstract Background The clinical diagnosis of neonatal sepsis remains difficult because of various challenges, such as culturing the bacteria and avoiding contamination. Therefore, this study aimed to identify bacterial pathogens in patients with clinically diagnosed neonatal sepsis by next-generation sequencing (NGS). Methods High-throughput NGS and traditional culture identification were performed by comparing samples from newborns with neonatal sepsis with healthy control infants. All blood samples were separately inoculated into anaerobic and aerobic bottles and incubated for 7 days at 37 °C, the positive specimens were then identified. Novel bacteria identified through high-throughput NGS were analysed using polymerase chain reaction (PCR), PCR products were verified by Sanger sequencing. Wilcoxon rank-sum and chi-square tests were performed to assess the significance of differences in species abundance between groups. Subjects were clinically diagnosed and hospitalized at the Pediatrics Department of Shenzhen Seventh People’s Hospital and Pediatrics Department of the Longhua Branch of Shenzhen People’s Hospital. Experiments were performed at the Shenzhen Seventh People’s Hospital. The experimental group comprised 45 newborns clinically diagnosed with neonatal sepsis (age: 0–28 days; 28 males, 17 females). Fifteen normal newborns aged 0–28 days (7 males, 8 females) were included as the control group. Results High-throughput NGS showed a positivity rate of 44% (20/45) for bacteria in patients clinically diagnosed with neonatal sepsis, whereas traditional bacterial culture identification showed a positivity rate of 0% (0/45). The four main bacterial species identified were Anoxybacillus kestanbolensis, Geobacillus vulcani, Klebsiella oxytoca, and Acinetobacter guillouiae. Conclusions A. kestanbolensis, G. vulcani, K. oxytoca, and A. guillouiae, newly discovered bacteria in patients with neonatal sepsis, were identified with high-throughput NGS. Which may result from maternal intrauterine infection or birth-canal infection and have a high clinical-cure rate. Owing to a lack of methods to culture these bacteria, their role in neonatal sepsis remains unclear. A definite diagnosis cannot rely solely on bacterial culture identification for patients with a suspected diagnosis and clinical diagnosis of neonatal sepsis and should involve other effective diagnostic techniques.

Evaluation of seismic bearing capacity is to be vital for design of strip foundations in earthquake areas. Combining the upper bound theorem of limit analysis, the discrete technique is successfully extended in this study to investigate the seismic ultimate bearing capacity of shallow strip foundations on rock masses considering the Rayleigh waves, in which the nonlinear HB failure criterion is used to describe the constitutive relation of rock masses. The failure model of foundation soil is generated using the discretization method, a “point by point” technique. The variations of shear modulus G of rock masses and seismic acceleration varying with the depth are taken into consideration. The generalized tangential technique is employed to avoid the difficulty resulting from the nonlinear HB failure criterion. A linear corresponding to the Mohr–Coulomb failure criterion, tangent to the nonlinear Hoek–Brown failure criterion, is used to derive the objective function that is to be minimized. By comparing with the existing results, the present approach is verified. The widely parametric studies are made to investigate the effect of different parameters, e.g. shear modulus G, mi, GSI, σci, γ, D, VR, on the seismic bearing capacity of strip foundations. The present method provides a reference for strip foundations designed in earthquake areas.

Highlights Comprehensive and systematic discussion of vascularized additive manufacturing scaffolds for bone tissue repair is provided. The development mechanism of blood vessels and the relationship between bone tissue engineering and blood vessels are discussed. Vascularized additively manufactured scaffolds in tissue repair are discussed in terms of issues, opportunities, and challenges. Intelligent vascularized 3D/4D/5D/6D-printed tissue scaffolds are discussed.

Constructing offshore wind turbines on artificial islands is considered a viable option, but negative skin friction (NSF) is a significant adverse factor that cannot be ignored. The NSF adversely affects the bearing capacity of pile foundations. Currently, design methods for studying the impact of NSF group effects mainly rely on empirical approaches. Moreover, existing experimental studies do not simulate the NSF experienced by offshore wind turbine pile groups on artificial islands. In order to further explore the impact of pile group effects on NSF experienced by offshore wind turbine pile foundations on artificial islands, this study conducted indoor model tests on single piles and 3 × 3 rectangular pile groups in sandy soil under uniformly distributed loading on surrounding soil. The experiment measured the settlement of piles at various positions within single piles and rectangular pile groups, as well as the settlement of the soil surrounding the piles and the NSF. Through calculations, the experiment determined the neutral points and NSF group effect coefficients for each pile. The results indicate that densely spaced pile groups are advantageous in reducing settlement of the surrounding soil, thereby mitigating the adverse effects of NSF. Due to the influence of pile group effects, different positions within the group experience varying degrees of NSF. Consequently, in practical engineering applications, settlement of both the pile groups and the surrounding soil should be calculated separately. Furthermore, design considerations for the uplift forces and neutral points of piles at different positions within the pile group should adhere to distinct standards.

Arch bridges have been constructed in China more than 1400 years ago. This study collated the details of 120 single-span arch bridges with spans of more than 100 m that have been constructed or undergoing construction in China over the recent three decades. The type proportion, span to rise ratio, spatial distribution, and span length of the 120 arch bridges were reported in this paper. An examination of the foundation of the 120 single-span arch bridges was further conducted. Based on the analysis of the arch bridge foundations, it was found that the foundation types can be grouped into enlarged footing, pile foundation, composite foundation, and “others”. Thus, the application rate of various foundation types, characteristics of each foundation type, and development trend of arch bridge foundations were investigated and discussed. Finally, case studies of single-span arch bridge with composite foundations consisting of open caisson and shaft, and foundation with barrette piles were reviewed. The construction techniques, applicable conditions and resistance characteristics of various foundations were analyzed and evaluated. The case studies highlighted in this paper illustrated the advancement, innovation and development in foundation engineering of single-span arch bridges in China.

Abstract Background The current genome-wide association study (GWAS) of Lewy body dementia (LBD) suffers from low power due to a limited sample size. In addition, the genetic determinants underlying LBD and the shared genetic etiology with Alzheimer’s disease (AD) and Parkinson’s disease (PD) remain poorly understood. Methods Using the largest GWAS summary statistics of LBD to date (2591 cases and 4027 controls), late-onset AD (86,531 cases and 676,386 controls), and PD (33,674 cases and 449,056 controls), we comprehensively investigated the genetic basis of LBD and shared genetic etiology among LBD, AD, and PD. We first conducted genetic correlation analysis using linkage disequilibrium score regression (LDSC), followed by multi-trait analysis of GWAS (MTAG) and association analysis based on SubSETs (ASSET) to identify the trait-specific SNPs. We then performed SNP-level functional annotation to identify significant genomic risk loci paired with Bayesian fine-mapping and colocalization analysis to identify potential causal variants. Parallel gene-level analysis including GCTA-fastBAT and transcriptome-wide association analysis (TWAS) was implemented to explore novel LBD-associated genes, followed by pathway enrichment analysis to understand underlying biological mechanisms. Results Pairwise LDSC analysis found positive genome-wide genetic correlations between LBD and AD (rg = 0.6603, se = 0.2001; P = 0.0010), between LBD and PD (rg = 0.6352, se = 0.1880; P = 0.0007), and between AD and PD (rg = 0.2136, se = 0.0860; P = 0.0130). We identified 13 significant loci for LBD, including 5 previously reported loci (1q22, 2q14.3, 4p16.3, 4q22.1, and 19q13.32) and 8 novel biologically plausible genetic associations (5q12.1, 5q33.3, 6p21.1, 8p23.1, 8p21.1, 16p11.2, 17p12, and 17q21.31), among which APOC1 (19q13.32), SNCA (4q22.1), TMEM175 (4p16.3), CLU (8p21.1), MAPT (17q21.31), and FBXL19 (16p11.2) were also validated by gene-level analysis. Pathway enrichment analysis of 40 common genes identified by GCTA-fastBAT and TWAS implicated significant role of neurofibrillary tangle assembly (GO:1902988, adjusted P = 1.55 × 10−2). Conclusions Our findings provide novel insights into the genetic determinants of LBD and the shared genetic etiology and biological mechanisms of LBD, AD, and PD, which could benefit the understanding of the co-pathology as well as the potential treatment of these diseases simultaneously.

BackgroundObservational studies have investigated the associations between antihypertensive drugs and fracture risk as well as bone mineral density (BMD), but yielding controversial results.MethodsIn this study, a comprehensive drug-target Mendelian randomization (MR) analysis was conducted to systematically examine the associations between genetic proxies for eight common antihypertensive drugs and three bone health-related traits (fracture, total body BMD [TB-BMD], and estimated heel BMD [eBMD]). The main analysis used the inverse-variance weighted (IVW) method to estimate the causal effect. Multiple MR methods were also employed to test the robustness of the results.ResultsThe genetic proxies for angiotensin receptor blockers (ARBs) were associated with a reduced risk of fracture (odds ratio [OR] = 0.67, 95% confidence interval [CI]: 0.54 to 0.84; P = 4.42 × 10-4; P-adjusted = 0.004), higher TB-BMD (β = 0.36, 95% CI: 0.11 to 0.61; P = 0.005; P-adjusted = 0.022), and higher eBMD (β = 0.30, 95% CI: 0.21 to 0.38; P = 3.59 × 10-12; P-adjusted = 6.55 × 10-11). Meanwhile, genetic proxies for calcium channel blockers (CCBs) were associated with an increased risk of fracture (OR = 1.07, 95% CI: 1.03 to 1.12; P = 0.002; P-adjusted = 0.013). Genetic proxies for potassium sparing diuretics (PSDs) showed negative associations with TB-BMD (β = -0.61, 95% CI: -0.88 to -0.33; P = 1.55 × 10-5; P-adjusted = 1.86 × 10-4). Genetic proxies for thiazide diuretics had positive associations with eBMD (β = 0.11, 95% CI: 0.03 to 0.18; P = 0.006; P-adjusted = 0.022). No significant heterogeneity or pleiotropy was identified. The results were consistent across different MR methods.ConclusionsThese findings suggest that genetic proxies for ARBs and thiazide diuretics may have a protective effect on bone health, while genetic proxies for CCBs and PSDs may have a negative effect.

Scour is a common phenomenon for laterally loaded underwater piles. The underwater piles used in different projects have different pile head conditions and pile types (flexible and rigid). On the one hand, an increasing number of rigid piles have begun to be used for underwater piles; on the other hand, flexible piles may be transformed into rigid piles after scour. This study presents a general method for laterally loaded monopile foundations (flexible and rigid), with both a free head and a fixed head, based on the curved strain wedge model under scour. The rationality and accuracy of the presented analytical solution are verified by two different case studies. The influence of scour dimension on the response of piles with different pile head conditions and pile types is studied. The results reveal that pile head condition, pile type and scour dimension all have a great influence on monopile response and should all be carefully considered. Under the same conditions as other parameters, monopile with a fixed pile head is less susceptible to scour dimension than monopile with a free head, and flexible monopile is less susceptible to scour dimension than rigid monopile.

Sidewall roughness is a key factor influencing the shaft resistance of rock-socketed piles. Owing to the difficulties in onsite measuring and the inconsistency in quantitatively characterizing the roughness degree of sidewalls, existing approaches for estimating the shaft resistance of rock-socketed piles often cannot take this factor into account. Based on the measured surface curves of the 68 sockets in No. 6# and 7# group piles of the Chishi Bridge on the Ru-Chen Expressway in China, sidewall roughness is described by introducing the roughness factor (RF) based on the Horvath and Monash models, respectively, while a statistical analysis of the sidewall roughness in rock-socketed sections is also conducted. In addition, an analytical solution to the shaft resistance of rock-socketed piles with consideration of sidewall roughness and the relative settlement of the pile–rocks interface (∆s), is proposed and further compared with the field load tests. The results showed that: the RF obtained by the Horvath model is bigger than that obtained by the Monash model; the larger RF is, the bigger the mobilized shaft resistance; the analytical solution generally overestimates the mobilized shaft resistance of rock-socketed piles under the same ∆s, and the deviation is less than 15% if ∆s is larger than 3.00 mm. The Horvath model is recommended to quantitatively characterize the roughness degree of sidewalls for its good operability in practice.

In the field of bone defect repair, 3D printed scaffolds have the characteristics of personalized customization and accurate internal structure. However, how to construct a well-structured vascular network quickly and effectively inside the scaffold is essential for bone repair after transplantation. Herein, inspired by the unique biological structure of “lotus seedpod”, hydrogel microspheres encapsulating deferoxamine (DFO) liposomes were prepared through microfluidic technology as “lotus seeds”, and skillfully combined with a three-dimensional (3D) printed bioceramic scaffold with biomimetic “lotus” biological structure which can internally grow blood vessels. In this composite scaffold system, DFO was effectively released by 36% in the first 6 h, which was conducive to promote the growth of blood vessels inside the scaffold quickly. In the following 7 days, the release rate of DFO reached 69%, which was fundamental in the formation of blood vessels inside the scaffold as well as osteogenic differentiation of bone mesenchymal stem cells (BMSCs). It was confirmed that the composite scaffold could significantly promote the human umbilical vein endothelial cells (HUVECs) to form the vascular morphology within 6 h in vitro. In vivo, the composite scaffold increased the expression of vascularization and osteogenic related proteins Hif1-α, CD31, OPN, and OCN in the rat femoral defect model, significantly cutting down the time of bone repair. To sum up, this “lotus seedpod” inspired porous bioceramic 3D printed scaffold with internal vascularization functionality has broad application prospects in the future.

Accuracy prediction of the yield strength and displacement of reinforced concrete (RC) columns for evaluating the seismic performance of structure plays an important role in engineering the structural design of RC columns. A new hybrid machine learning technique based on the least squares support vector machine (LSSVM) and the particle swarm optimization (PSO) algorithm is proposed to predict the yield strength and displacement of RC columns. In this PSO-LSSVM model, the LSSVM is applied to discover the mapping between the influencing factors and the yield strength and displacement, and the PSO algorithm is utilized to select the optimal parameters of LSSVM to facilitate the prediction performance of the proposed model. A dataset covering the PEER database and the available experimental data in relevant literature is established for model training and testing. The PSO algorithm is then evaluated and compared with other metaheuristic algorithms based on the experiment’s database. The results indicate the effectiveness of the PSO employed for improving the prediction performance of the LSSVM model according to the evaluation criteria such as the root mean square error (RMSE), mean absolute error (MAE) and coefficient of determination (R2). Overall, the simulation demonstrates that the developed PSO-LSSVM model has ideal prediction accuracy in the yield properties of RC columns.

Soft soil is widely distributed in the riverside area of southern China. The creep deformation characteristics of the soft soil affect the long-term stability of the structure foundation, which cannot be ignored. Through the triaxial drainage creep test, the creep characteristics of riverside soil with a soft interlayer from Jiangsu Province were studied. The test results show that the creep procedure of the soft soil is divided into two stages, exhibiting steady-state creep and shear shrinkage characteristics with time and stress growth, which presents typical nonlinear behavior. Additionally, the confining pressure and stress are critical factors affecting creep characteristics. The fractal dashpot based on fractal derivative theory is introduced in place of the Abel dashpot in the classical fractional Burgers model; a fractal Burgers creep model with few parameters, high precision, and clear physical significance is established. Additionally, an analytical solution to the creep model is given. The model parameters are determined by fitting the test results, and the comparison shows that the results estimated with the model are more accurate than those estimated with the traditional model. The sensitivity analyses of the model parameters reveal the influence of key parameters on the creep characteristics of the soil. The results further confirm that the proposed fractal Burgers model can characterize the creep behavior of viscoelastic soil. These observations are extremely important for predicting the foundation displacement and formulating measures to prevent the deformation, which can provide a reference for engineering applications in the riverside area of southern China.

Gravel cushions have been introduced as a practical and efficient seismic isolation technology to ensure the safety of nuclear power plants. This study investigated the seismic isolation effect of a gravel cushion by conducting a series of shaking table tests on a model foundation with a cushion built of three different types of graded aggregates (single-sized (2–5 mm), two-sized (2–5 mm:5–10 mm = 3 : 1), and continuously graded) under input El Centro seismic waves with three different peak accelerations (0.1 g, 0.2 g, and 0.3 g). The testing results showed that the seismic isolation effect of the gravel cushion increased with the peak seismic acceleration. The gravel cushion built with single-sized aggregates had better seismic isolation performance than gravel cushions built with two-sized or continuously graded aggregates. Under input seismic waves with 0.1 g peak acceleration, the single-sized aggregate gravel cushion still had a seismic isolation effect with a vibration reduction rate of approximately 11.81%, whereas the other two gravel cushions had no effect. Under input seismic waves with peak accelerations of 0.2 g and 0.3 g, all three gravel cushions had seismic isolation effects with vibration reduction rates of approximately 18.63% and 17.92%, respectively. An empirical model is proposed for predicting the vibration reduction rate of the cushion. Under input seismic waves with 0.3 g peak acceleration, the ultimate vibration reduction rate of the gravel cushion fell between 20.44% and 31.33%. The gravel cushion is an excellent option for nuclear power plant foundations with high requirements for seismic isolation, provided that the required bearing capacity is satisfied.

Idiopathic pulmonary fibrosis (IPF) is a type of scarring lung disease characterized by a chronic, progressive, and irreversible decline in lung function. The genetic basis of IPF remains elusive. A transcriptome-wide association study (TWAS) of IPF was performed by FUSION using gene expression weights of three tissues combined with a large-scale genome-wide association study (GWAS) dataset, totally involving 2,668 IPF cases and 8,591 controls. Significant genes identified by TWAS were then subjected to gene ontology (GO) and pathway enrichment analysis. The overlapped GO terms and pathways between enrichment analysis of TWAS significant genes and differentially expressed genes (DEGs) from the genome-wide mRNA expression profiling of IPF were also identified. For TWAS significant genes, protein–protein interaction (PPI) network and clustering modules analyses were further conducted using STRING and Cytoscape. Overall, TWAS identified a group of candidate genes for IPF under the Bonferroni corrected P value threshold (0.05/14929 = 3.35 × 10–6), such as DSP (PTWAS = 1.35 × 10–29 for lung tissue), MUC5B (PTWAS = 1.09 × 10–28 for lung tissue), and TOLLIP (PTWAS = 1.41 × 10–15 for whole blood). Pathway enrichment analysis identified multiple candidate pathways, such as herpes simplex infection (P value = 7.93 × 10–5) and antigen processing and presentation (P value = 6.55 × 10–5). 38 common GO terms and 8 KEGG pathways shared by enrichment analysis of TWAS significant genes and DEGs were identified. In the PPI network, 14 genes (DYNLL1, DYNC1LI1, DYNLL2, HLA-DRB5, HLA-DPB1, HLA-DQB2, HLA-DQA2, HLA-DQB1, HLA-DRB1, POLR2L, CENPP, CENPK, NUP133, and NUP107) were simultaneously detected by hub gene and module analysis. In conclusion, through integrative analysis of TWAS and mRNA expression profiles, we identified multiple novel candidate genes, GO terms and pathways for IPF, which contributes to the understanding of the genetic mechanism of IPF.

Rock–socketed pile under lateral loading is important in engineering practice. It is very significant to calculate the lateral bearing capacity of rock–socketed piles since few studies focus on this problem. The rock cohesion and instantaneous angle of friction, which have a high correlation with confining pressure, are obtained. Moreover, the strain wedge model is modified from three aspects: the assumption of nonlinear displacement; the stress level related to cohesion and friction angle; and the pile side resistance. Then, the modified strain wedge model is employed to deduce p–y criterion for rock–socketed pile considering Hoek–Brown failure criterion. The fourth-order partial differential equation constructed according to the p–y curve is solved by using the finite difference method. A numerical method with 2 m diameter rock-socketed pile is given to validate the rationality of the proposed method. It is shown that the proposed could predict the pile deformation well, and the responses are considered acceptable.

The addition of chemical or mechanical materials, such as fibers or stabilizers, is frequently utilized in geotechnical engineering to improve the mechanical properties of problematic soils. In this study, great efforts have been made to obtain insight into the mechanical properties of the natural, fiber, and chemical additive-stabilized soil in heavy-haul railway embankment. A series of triaxial compression tests are conducted on the stabilized samples of different preparation conditions, including water content, compaction degree, confining pressure, fiber content, fiber length, stabilizer content, and curing time. Results show that the shear strength of natural soils shows a distinct increase after adding fiber and chemical additive stabilization. The optimum fiber content and length for fiber stabilization are 0.2% and 12 mm, respectively. The initial tangential modulus and failure stress of chemical stabilized samples increase with the increase of additive dosage or curing time. Meanwhile, a brittle characteristic is observed. In the process of determining the reinforcement methods in practical projects, several other considerations are included, such as equipment and time available, especially for stabilized soils. The fiber-reinforced soils and stabilized soils are efficient for increasing the shear strength and changing of the brittleness character of the heavy-haul railway embankment. The results of this study could provide a valuable reference for geotechnical engineers dealing with soil problems, especially for the heavy-haul railway embankment.

The vibration acceleration during a freezing period was monitored in the Beijing-Harbin railway subgrade, and its frequency characteristics were studied. The results show the following. (1) The vibration acceleration frequency of the railway subgrade was divided into three main bands: the first frequency band is caused by the vehicle wheelbase, the second frequency band is caused by the sleeper spacing, and the third frequency band is mainly affected by the track irregularity spectrum and site structure. (2) The fitted dominant frequency, as can be seen from the monitored results, is in good agreement with the calculated value from the vibration frequency calculation formulas. (3) From the monitoring, it can be seen that train type, traveling speed, and train formation have a significant influence on the dominant frequencies of the first and second bands. Train formation, load, and distance from the track have a great influence on the amplitude of each frequency band.

This paper presents a field study on the axial behavior of four large-diameter drilled shafts embedded in coarse sand. The grouting and loading test procedures were reported. The bearing capacity of shafts (TS1 and TS2) and grouted drilled shafts (TS3 and TS4) were herein determined by the bi-directional static test and top-down load test, respectively. The enhancement mechanism of bearing characteristics of the grouted shafts was discussed in detail. The test results indicate that the bearing characteristics and load transfer mechanisms of the test shafts were significantly affected by the quantity of pressurized cement slurry and the mechanical properties of the soil surrounding the shafts. Furthermore, the tip resistance of shaft can be mobilized more rapidly and fully after grouting, the side and tip resistance are mobilized in a more synchronized and coordinated manner due to the pre-mobilization of the grouted cement. Additionally, the standard penetration test (SPT) prediction model was introduced to calculate and predict the SPT blow counts of soil after grouting. The results show that the post grouting has a more obvious improvement on the strength of cohesionless soil.

Dendritic cells (DCs) play important roles in initiation of the pathogenic processes of autoimmune disorders, such as rheumatoid arthritis (RA). Tolerogenic dendritic cells (tolDCs) are generated from naïve DCs and induce T cell tolerance; thus, they represent a promising strategy for specific cellular therapy for autoimmune diseases. In this study, we generated green fluorescent protein (GFP)-labeled tolDCs and confirmed their phenotypes and biological functions. We found that tolDCs suppressed the memory lymphocyte response and exhibited strong tolerogenic potential; thus, these cells show promise for the treatment of autoimmune diseases. Additionally, a collagen-induced arthritis (CIA) mouse model was used to test the role of tolDCs in vivo. The results of a further mechanistic experiment revealed that tolDCs suppressed inflammatory arthritis at least partially by up-regulating regulatory T (Treg) cells. Collectively, our data suggest that tolDCs may be used as a promising alternative therapy for inflammatory arthritis.

This study examined the influence of osteoprotegerin (OPG) gene transfer on a murine collagen-induced arthritis model. A single periarticular injection of AAV-OPG or AAV-LacZ on the arthritic paw successfully incorporated the exogenous gene to the local tissue and resulted in marked transgene expression in the joint homogenate for at least three weeks. Clinical disease scores were significantly improved in OPG treated mice starting at 28-day post-treatment (P

The karst that is dominated by medium-weathered limestone and caves with various spatial features is widely distributed in the northern Fujian Province. This paper discusses the load-bearing behaviors of post-grouting tubular piles in karst region of north Fujian Province with reference to the prestressed tubular piles adopted in the residential buildings of Haixi Comprehensive Trade City Phase II Project in Sanming City. The load-settlement curve, pile side friction resistance, and pile end resistance of tubular piles are analyzed by finite element numerical simulations and field static load tests. The load-bearing behaviors of prestressed tubular piles under karst geological conditions with two different spatial features are comparatively investigated, and the effectiveness of tubular pile reinforcement is verified by field settlement observation. The results reveal that the finite element numerical model can effectively simulate the tubular pile-soil interaction. The use of pile end post-grouting of prestressed tubular piles in the karst region can significantly increase their load-bearing capacities. The top settlements of grouted tubular piles under the maximum test load can be reduced by 16.8%-22.3% compared with these of ungrouted test piles, and the theoretical simulated ultimate load-bearing capacity can be increased by 27.3%. The adoption of pile end post-grouting technique can reduce the pile end displacement of tubular piles and improve the proportion of pile end resistance. Plastic-hard plastic breccia silty clay can be used as a bearing stratum for post-grouting to achieve excellent grouting performance. The bead-shaped karst caves are more unfavorable to the exertion of load-bearing capacity of the tubular piles than the karst caves filled with plastic-hard plastic breccia silty clay to which the piles have direct access. The field monitored average settlements of the 19# and 17# buildings under karst geological conditions with two different spatial features are -12.88 mm and -8.98 mm, respectively, both of which do not exceed the warning value, indicating that it is feasible for the project to adopt the pile end post-grouting technique of the tubular piles. The achievements of this study help to further reveal the load-bearing mechanism of this type of pile, which can provide a basis for its engineering design and construction optimization. [ABSTRACT FROM AUTHOR]