The design of reinforced concrete beams for shear in current practice: A new analytical model

Londhe, R.S. Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.2

The present paper reviews the shear design (of reinforced concrete beam) provisions of four different national codes and proposes a new but simplified shear strength empirical expression, incorporating variables such as compressive strength of concrete, percentage of longitudinal and vertical steel/s, depth of beam in terms of shear span-to-depth ratio, for reinforced concrete (RC) beams without shear reinforcement. The expression is based on the experimental investigation on RC beams without shear reinforcement. Further, the comparisons of shear design provisions of four National codes viz.: (i) IS 456-2000, (iii) BS 8110-1997, (iv) ACI 318-2002 (v) EuroCode-2-2002 and the proposed expression for the prediction of shear capacity of normal beam/s, have been made by solving a numerical example. The results of the numerical example worked out suggest that there is need for revision in the shear design procedure of different codes. Also, the proposed expression is less conservative among the IS, BS & Eurocode.

Synthesis of 2-Arylbenzothiazoles Catalyzed by Biomimetic Catalyst, β-Cyclodextrin

Londhe, Balaji S.,Pratap, Umesh R.,Mali, Jyotirling R.,Mane, Ramrao A. Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.8

Cyclocondensation of 2-aminothiophenol and aryl/heteryl aldehydes has been carried using biomimetic catalyst, $\beta$-Cyclodextrin in water and obtained 2-aryl/heteryl benzothiazoles with better to excellent yields. This biomimetic catalyzed route is simple, economic, and environmentally benign.

Study of Patients with Bilateral Knee Osteoarthritis Undergoing Total Knee Replacement Procedure with Coexisting Lumbar Spondylosis Symptoms

Londhe Sanjay Bhalchandra,Shah Ravi Vinod,Patwardhan Meghana,Doshi Amit Pankaj,Londhe Shubhankar Sanjay,Subhedar Kavita,Kundnani Vishal G.,Patel Jwalant Y. 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.6

Study Design: This is a prospective cohort study involving patients who were followed for 2 years after total knee replacement (TKR) to determine changes in lumbar spine and knee symptoms. Purpose: The objectives of this study were to determine the percentage of patients undergoing bilateral TKR who present with coexisting lumbar spine problems and determine if TKR relieves lumbar spine symptoms. Overview of Literature: No studies quantify the percentage of TKR patients who experience relief of lumbar spine symptoms after TKR surgery. Methods: The study included 200 patients (164 females, 36 males) undergoing primary TKR. Follow-up was performed at 4 weeks, 3, 6, 12, and 24 months. Lumbar spine and knee symptom improvements were assessed using the Oswestry Disability Index (ODI) and Oxford Knee Score, respectively. Results: All 200 patients undergoing bilateral TKR presented with radiographic lumbar spine degenerative pathology; 60% (n=120) of the patients presented with moderate to severe clinical symptoms of lumbar spondylosis, including 54% (n=108) with degenerative lumbar spondylosis and lumbar canal stenosis and 6% (n=12) with degenerative spondylolisthesis. Of the 120 patients who presented with lumbar spine problems, 90% (n=108) reported improvement in their symptoms; the ODI score improved from 42.5%±4.1% preoperative score to 15.6%±2.3% postoperative score (p-value<0.001). Of the 12 patients with no improvement, 10 patients underwent percutaneous procedures for their lumbar spine pathology with good results, one patient underwent surgery, and one declined any intervention. Conclusions: A significant number of patients (60%) undergoing bilateral TKR also present with symptomatic lumbar spine problems. Patients with mild to moderate lumbar spine degenerative symptoms and no associated severe radiating pain on activity are more likely to experience relief of their symptoms post-TKR.

Shear strength analysis and prediction of reinforced concrete transfer beams in high-rise buildings

Londhe, R.S. Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.37 No.1

Results of an experimental investigation on the behavior and ultimate shear capacity of 27 reinforced concrete Transfer (deep) beams are summarized. The main variables were percent longitudinal(tension) steel (0.28 to 0.60%), percent horizontal web steel (0.60 to 2.40%), percent vertical steel (0.50to 2.25%), percent orthogonal web steel, shear span-to-depth ratio (1.10 to 3.20) and cube concrete compressive strength (32 MPa to 48 MPa).The span of the beam has been kept constant at 1000 mm with100 mm overhang on either side of the supports. The result of this study shows that the load transfer capacity of transfer (deep) beam with distributed longitudinal reinforcement is increased significantly. Also, the vertical shear reinforcement is more effective than the horizontal reinforcement in increasing the shear capacity as well as to transform the brittle mode of failure in to the ductile mode of failure. It has been observed that the orthogonal web reinforcement is highly influencing parameter to generate the shear capacity of transfer beams as well as its failure modes. Moreover, the results from the experiments have been processed suitably and presented an analytical model for design of transfer beams in high-rise buildings for estimating the shear capacity of beams.

Synthesis of 2-Arylbenzothiazoles Catalyzed by Biomimetic Catalyst, β-Cyclodextrin

Balaji S. Londhe,Umesh R. Pratap,Jyotirling R. Mali,Ramrao A. Mane 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.8

Cyclocondensation of 2-aminothiophenol and aryl/heteryl aldehydes has been carried using biomimetic catalyst, β-Cyclodextrin in water and obtained 2-aryl/heteryl benzothiazoles with better to excellent yields. This biomimetic catalyzed route is simple, economic, and environmentally benign.

Comparison of Time Taken in Conventional versus Active Robotic-Assisted Total Knee Arthroplasty

Sanjay Bhalchandra Londhe,Santosh Shetty,Vijay Shetty,Clevio Desouza,Paras Banka,Nicholas Antao 대한정형외과학회 2024 Clinics in Orthopedic Surgery Vol.16 No.2

Background: Computer- and robotic-assisted total knee replacement procedures have been shown to improve the accuracy of the implant size. It also allows dynamic confirmation of the implant and limb alignment during total knee arthroplasty (TKA). The major inhibition of the arthroplasty surgeon in adapting to the robotic-assisted TKA (RA-TKA) is the extra time spent during the registration process and milling of the bone with the robot. The aim of the study was to ascertain the extra time spent during these 2 steps as compared to the conventional TKA (C-TKA). Methods: It is a prospective study involving 30 patients each in the conventional TKA and RA-TKA operated by the same surgical team. The patients were given a choice between the C-TKA and RA-TKA and consecutive 30 cases in each group were studied by an independent observer. In the C-TKA group, the time for the application of appropriate zigs and execution of the bone cuts and soft-tissue release was recorded whereas in the RA-TKA group, the time taken for fixation of the tibial and femoral arrays and bone registration and bone milling with robot and required soft-tissue release was measured. Results: The preoperative patient characteristics were the same in both groups. The time taken in the C-TKA and RA-TKA groups was 24.77 ± 1.92 minutes and 25.03 ± 3.27 minutes, respectively, which is statistically insignificant (p = 0.709). Conclusions: The study findings show that RA-TKA does not take additional time than C-TKA.

Electrosprayed graphene decorated with ZnO nanoparticles for supercapacitors

Samuel, Edmund,Londhe, Priyanka U.,Joshi, Bhavana,Kim, Min-Woo,Kim, Karam,Swihart, Mark T.,Chaure, Nandu B.,Yoon, Sam S. Elsevier 2018 Journal of alloys and compounds Vol.741 No.-

<P><B>Abstract</B></P> <P>A binder-free nanocomposite consisting of ZnO nanoparticles (NPs) grown directly on graphene sheets by electrospraying was fabricated for use as an electrode material in supercapacitors. The optimal concentrations of graphene and ZnO NPs were determined from the capacitive characteristics of the composite. Scanning electron microscopy confirmed that the ZnO NPs grew in a uniformly distributed manner on the graphene sheets and that they exhibited negligible agglomeration. Further, X-ray diffraction analysis confirmed that ZnO growth was preferentially oriented along (100) plane in the ZnO/graphene composite. A symmetric supercapacitor fabricated using this composite exhibited an energy density of 67 mWh·cm<SUP>−3</SUP> and power density of 6000 mW·cm<SUP>−3</SUP>. The composite also showed good long-term cycling performance, retaining 90% of its capacitance after 1000 galvanostatic charge/discharge cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZnO/graphene electrodes for supercapacitor applications have been fabricated using electrospraying. </LI> <LI> A symmetric supercapacitor exhibited an energy density of 67 mWh·cm-3 and power density of 6000 mW·cm<SUP>−3</SUP>. </LI> <LI> The composite retained 90% of its capacitance after 1000 galvanostatic charge and discharge cycles. </LI> <LI> The graphene sheets prevented agglomeration of the ZnO nanoparticles. </LI> </UL> </P>

Discovery of non-peptidic small molecule inhibitors of cyclophilin D as neuroprotective agents in Aβ-induced mitochondrial dysfunction

Park, Insun,Londhe, Ashwini M.,Lim, Ji Woong,Park, Beoung-Geon,Jung, Seo Yun,Lee, Jae Yeol,Lim, Sang Min,No, Kyoung Tai,Lee, Jiyoun,Pae, Ae Nim Springer-Verlag 2017 Journal of computer-aided molecular design Vol.31 No.10

Modelling dissolved oxygen and biochemical oxygen demand using data-driven techniques

Pali Sahu,Shreenivas N Londhe,Preeti S Kulkarni 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.3

Precise quantification of Biochemical oxygen demand (BOD) and Dissolved oxygen (DO) are critically important for water quality assessment as well as for development of various management policies. To calculate BOD and DO for any water sample, standard technique Winkler-Azide method is used which is cumbersome and prone to measurement error. Therefore, there is a need to device alternate Data Driven Technique (DDT). In the present study, three different DDT: Artificial Neural Network (ANN), Multi Gene Genetic Programming (MG-GP) and M5 Model Tree (M5T) have been used for DO as well as BOD prediction for 3 separate stretches of Mula-Mutha River situated in Pune, India. Additionally, attempt has been made to predict BOD using modelled DO; which shows possibility of using modelled parameter in development of another model. Performance of the models was assessed through, root mean square error (RMSE); mean absolute relative error (MARE) and coefficient of correlation (R). Results based on 3 stations indicate that ANN and MGGP both outperformed with R above 0.85 and RMSE below 1 mg/L for 2 stations out of 3. MGGP and M5T can grasp the influence parameter which can be seen from the input frequency distribution in MGGP and coefficient of input parameters in M5T.

Application of artificial neural networks for dynamic analysis of building frames

Shardul G. Joshi,Shreenivas N. Londhe,Naveen Kwatra 사단법인 한국계산역학회 2014 Computers and Concrete, An International Journal Vol.13 No.6

Many building codes use the empirical equation to determine fundamental period of vibration where in effect of length, width and the stiffness of the building is not explicitly accounted for. In the present study, ANN models are developed in three categories, varying the number of input parameters in each category. Input parameters are chosen to represent mass, stiffness and geometry of the buildings indirectly. Total numbers of 206 buildings are analyzed out of which, data set of 142 buildings is used to develop these models. It is demonstrated through developed ANN models that geometry of the building and the sizes of the columns are significant parameters in the dynamic analysis of building frames. The testing dataset of these three models is used to obtain the empirical relationship between the height of the building and fundamental period of vibration and compared with the similar equations proposed by other researchers. Experiments are conducted on Mild Steel frames using uniaxial shake table. It is seen that the values obtained through the ANN models are close to the experimental values. The validity of ANN technique is verified by experimental values.