Renato Perucchio

• University of Rochester

The structural assessment of masonry construction often requires the use of nonlinear 2- and 3D finite element analysis. This work describes a strategy for using energy outputs from such analyses to accurately assess failure conditions precipitated by increasing lateral load. The methodology relies on the analogy between plastic strains and fractur...

Huaca de la Luna is a monumental earthen complex near Trujillo in north coastal Peru built from 200 AD to 850 AD by the Moche civilization. Its principal structure – a stepped pyramid built with millions of adobe bricks on sloping bedrock and soft soil – presents severe structural damage at the NW corner. The static and dynamic response of the pyra...

The Moche civilization constructed the monumental adobe complex Huaca de la Luna in phases from 100–650 CE. Its main stepped pyramid is the focus of this study. Located at the foot of Cerro Blanco, near coastal Trujillo, Perú, the structure is subject to Pacific Ring of Fire seismic activity. Damage to the northwest corner and looting on the north...

This study contributes to the structural assessment of the main pyramid in the archaeological complex of Huaca de la Luna, Peru. Built with millions of adobe bricks by the Moche civilization (200–850 A.D.), the monument is one of the largest adobe structures in the world. Located in a seismically active area, the monument shows signs of severe natu...

Concrete vaults of the Late Classic Maya complex of Bonampak, Chiapas, Mexico (580-800 C.E.) are well-preserved examples of the one-story, corbelled style of the Maya and they house some of the best examples of murals in the Americas. To assess the monuments in light of the seismic risk of the region and the structures’ cultural value, the present...

Our research aims at evaluating the seismic vulnerability of concrete vaulted buildings of the Late Classic Maya complex of Bonampak, Chiapas, Mexico (circa AD. 580-800). Bonampak is famous for the Maya murals present in Structure 1, which are arguably the most complete and best-preserved murals of the ancient Americas. Structure 3-the focus of the...

The present paper presents results of a comprehensive engineering analysis for understanding the current structural damage condition of a sector of one of the most representative archaeological complexes in Perú: the main Moche culture pyramid of Huaca de la Luna. It is estimated that this pyramid was built in stages with adobe masonry between 100...

Finite element analysis (FEA) is used to analyze the static and dynamic structural behavior providing important information for the conservation of monuments in cultural heritage. Accurate solid models are fundamental in this type of analysis, but the structural changes introduced during the lifetime of the monument produce complex geometrical conf...

A methodology for computing the stress distribution of vascular tissue using finite element-based, intravascular ultrasound (IVUS) reconstruction elastography is described. This information could help cardiologists detect life-threatening atherosclerotic plaques and predict their propensity to rupture. The calculation of vessel stresses requires th...

This poster presents results of geophysical tests to help assess the geotechnical conditions of the archaeological complex of Huaca de la Luna located near the coastal city of Trujillo, Peru. To characterize the foundation soils of the areas of interest of the huaca Multichannel Analysis of Surface Waves (MASW), Seismic Cone Penetration Tests (SCPT...

The Saint Peter Apostle church of Andahuaylillas, in Cusco, is an emblematic example of a large number of early colonial adobe churches in Peru. The church is comprised of a main nave, six chapels and a bell tower, and features a typical ‘par y nudillo’ roof system. Although this monument is considered to be one of the most important churches due t...

This paper presents the first round of on-site investigations and numerical analysis applied to the archaeological complex of Huaca de la Luna, aiming at its structural assessment. The studied complex is a massive adobe construction located in Trujillo, a northern city of Peru, which was built by the Moche Civilization from 100 AD to 650 AD. An on-...

The morphogenetic process of cardiac looping transforms the straight heart tube into a curved tube that resembles the shape of the future four-chambered heart. Although great progress has been made in identifying the molecular and genetic factors involved in looping, the physical mechanisms that drive this process have remained poorly understood. R...

"Huaca de la Luna" is a massive adobe complex in Trujillo, Peru, built by the Moche civilization (100-650 AD) and brought to light through archaeological excavations began in 1991. The paper presents the first stage of a multidisciplinary study regarding the structural state of the construction. Considering the complex vast size, structural element...

The church of Andahuaylillas in Cusco is an emblematic example of a large number of adobe churches in Peru. The investigation of the seismic behaviour of these constructions has received almost no attention, even if they are placed in high seismicity zones. This paper presents a study on the seismic behaviour of the Andahuaylillas church, which is...

Structural changes introduced during the life of monuments contribute to produce complex geometrical configurations that cannot be properly represented in standard solid modeling systems designed for current engineering applications such as finite element analysis (FEA). Likewise, point-based 3D meshes - laser-scanner or photogrammetric -, although...

The vaulted concrete monuments of ancient Rome have an unreinforced concrete core of pozzolanic mortar and decimeter-sized coarse aggregate. An assessment of the mechanical and fracture properties of a reproduced Trajanic-era (c. 100AD) mortar is the subject of the present work. Description of a newly developed arc-shaped three-point bending test,...

An in-depth structural analysis is used to explore the design and functionality of the Great Hall of Trajan’s Markets (110 CE), a large Imperial monument cross vaulted in unreinforced Roman concrete. Following a combined approach, the analysis utilizes both field quantities and aggregate equilibrium quantities to determine how the load paths of the...

Mechanics plays a major role in heart development. This paper reviews some of the mechanical aspects involved in theoretical modeling of the embryonic heart as it transforms from a single tube into a four-chambered pump. In particular, large deformations and significant alterations in structure lead to highly nonlinear boundary value problems. Firs...

Accurate material properties of developing embryonic tissues are a crucial factor in studies of the mechanics of morphogenesis. In the present work, we characterize the viscoelastic material properties of the looping heart tube in the chick embryo through nonlinear finite element modeling and microindentation experiments. Both hysteresis and ramp-h...

The analysis of the biomechanics of growth and remodeling in soft tissues requires the formulation of specialized pseudoelastic constitutive relations. The nonlinear finite element analysis package ABAQUS allows the user to implement such specialized material responses through the coding of a user material subroutine called UMAT. However, hand codi...

C-looping is the morphomechanical process through which the initially straight embryonic heart tube (HT) reconfigures into a doubly bent, twisted, swollen, c-shaped tube [1] between stages HH10− and HH12 [2]. According to the biomechanical hypotheses proposed by Taber [3], the ventral and rightward bending of the heart tube are intrinsic to the ini...

The highly developed concrete composites used to realize the monumental structures of Imperial Rome are remarkable engineering materials. Their mechanical properties are attested to by the numerous constructions still intact after millennia of usage. The assessment of these mechanical properties – particularly in tension and fracture – is the objec...

The concrete composites used to realize the monumental structures of Imperial Rome are remarkable engineering materials. While the endurance of intact constructions such as the Pantheon evinces the concretes’ durability, such durability mostly serves to preserve the mechanical properties, which are responsible both for the monuments’ original creat...

HH Stage 22 chick heart inflated ex ovo with perfusate containing propidium iodide (red) and 3000 MW dextran (green), viewed here in left sagittal plane by confocal microscopy of acrylamide slab sections. Stretch-sensitive membrane leaks were conspicuous along subendocardial trabeculae near the apex of the looped ventricle (bottom) and along inner...

It is often difficult for commercial finite element (FE) analysis developers to implement highly specialized materials. Therefore, it is advantageous to allow users to code subroutines for specialized constitutive equations. The disadvantage is that the user must learn and understand the developer’s implementation of the nonlinear FE formulation. I...

During cardiac development, the initially straight heart tube bends ventrally and rotates towards the right side of the embryo. The biomechanical mechanism of cardiac looping is still unclear, but it has been hypothesized to be related to the unbalanced forces in the left and right omphalomesenteric veins (OVs) generated by cytoskeletal contraction...

The hypothesis that inner layers of contracting muscular tubes undergo greater strain than concentric outer layers was tested by numerical modeling and by confocal microscopy of strain within the wall of the early chick heart. We modeled the looped heart as a thin muscular shell surrounding an inner layer of sponge-like trabeculae by two methods: c...

Significant progress has been made in the study of the developmental biomechanics of the embryonic chick heart through the use of the finite element method (FEM) [1, 2, 3]. Our work focuses on the geometry of the Hamburger-Hamilton stages 9–12 embryonic chick heart, approximately the time when the heart begins to function and undergoes drastic morp...

Mechanical force is believed to play a significant role in regulating the morphogenetic process of cardiac looping. To better understand this process, it is crucial to determine the material properties of the early chick heart. It is well known that biological tissues are viscoelastic, however previous data on early stage embryonic heart tissue sho...

The Great Hall of the Trajan's Markets in Rome is the oldest surviving example of a cross vaulted structure built entirely in Roman pozzolanic concrete (opus caementicium.) The Finite Element method is used to investigate the structural behavior of the Great Hall under static gravitational loads and with the assumption of Roman concrete behaving as...

Early in development, the heart is a single muscle-wrapped tube without formed valves. Yet survival of the embryo depends on the ability of this tube to pump blood at steadily increasing rates and pressures. Developmental biologists historically have speculated that the heart tube pumps via a peristaltic mechanism, with a wave of contraction propag...

In fold-thrust belts, sedimentary cover rocks are detached from undeformed basement and undergo crustal-scale shortening and internal deformation. We have investigated a three-dimensional (3-D), nonlinear, elastic-plastic finite element model using the restored Provo salient of the Sevier belt as our initial configuration. In the model the deformed...

A skeleton modeling procedure for computing the continuous structural orientation from the discrete curve skeleton yielded by 3D image thinning is presented. The proposed modeling procedure consists of three consecutive operations: (1) topological segmentation to divide a curve skeleton into branches; (2) branch filtering to remove spurious branche...

Mechanics plays a major role in heart development. This paper reviews some of the mechanical aspects involved in theoretical modeling of the embryonic heart as it transforms from a single tube into a four-chambered pump. In particular, large deformations and significant alterations in structure lead to highly nonlinear boundary value problems. Firs...

Cardiac looping, which begins with ventral bending and rightward rotation of the primitive heart tube, is an essential morphogenetic event that occurs early in vertebrate development. The biophysical mechanism that drives this process is unknown. It has been speculated that increased stiffness along the dorsal side of the ventricle combined with an...

We introduce a new topology-preserving 3D thinning procedure for deriving the curve voxel skeleton from 3D binary digital images. Based on a rigorously defined classification procedure, the algorithm consists of sequential thinning iterations each characterized by six parallel directional sub-iterations followed by a set of sequential sub-iteration...

A numerical homogenization procedure for deriving the constitutive relations of the trabeculated embryonic myocardium is presented. This procedure is based on voxel modeling, nonlinear Finite Element analysis, and nonlinear data regression. Voxel reconstructions derived from digitized serial sections are used to construct local Finite Element meshe...

A complete understanding of joint kinematics is important to the study of general locomotion, the diagnosis of abnormal joint behavior resulting from disease or injury, the quantitative assessment of treatment and the design of better prosthetic devices. The knee motion during passive flexion or specific activities, such as walking, running and sta...

The mechanical response of the trabeculated ventricle at stage 21 is modeled using nonlinear finite element analysis. The objective is to investigate how stresses and strains resulting from ventricular activation and blood pressure modulate the growth and remodeling of the trabeculated wall and of the ventricle. A multiscale approach, consisting of...

Early in development, the initially straight heart tube bends (loops) into a curved tube. Two theoretical models are proposed for the mechanism of cardiac looping. In one model, a residual stress in the dorsal mesocardium drives looping, while in the other model, microfilament contraction drives the deformation. The results show that the models are...

In this paper we present a fast, inherently parallel, two-level multigrid (TLMG) algorithm for solving quadratic finite element models containing tetrahedral meshes. The basic idea is to integrate a TLMG algorithm with hierarchical octree structure based on Recursive Spatial Decomposition (RSD). The new hierarchical TLMG (HTLMG) algorithm combines...

This paper introduces an automatic self-adaptive finite element system for 3-D stress analysis of homogeneous elastic solids described in a Solid Modelling System (SMS). This system reduces the role of the analyst into two basic tasks: defining the problem (i.e. geometry, material properties and boundary conditions) and specifying the desired accur...

A mixed finite element method is presented for geometrically and materially non-linear analysis of anisotropic incompressible hyperelastic materials. An incremental iteractive total Lagrangian formulation is adopted. The nodal displacements and the hydrostatic pressure are independently interpolated leading to a mixed system of equations, with char...

A recursive spatial decomposition (RSD) R(S) of a solid S is an approximation of 5 consisting of regular cells that either lie inside S (IN cells) or intersect the boundary of S (NIO cells). Automatic finite element meshing based on RSD has many advantages, compared to ‘global’ methods, particularly in the areas of adaptive meshing and parallel pro...

In the companion paper, we discussed the applicability of a recursive spatial decomposition (RSD) based automatic meshing procedure for concurrent implementation. This paper describes an automatic substructuring scheme based on RSD of the domain, that can be closely integrated with the RSD-based automatic meshing procedure. The hierarchical data st...

This paper discusses an automatic meshing scheme that is suitable for parallel processing. Meshes derived from solid models through recursive spatial decompositions inherit the hierarchical organization and the spatial addressability of the underlying grid. These two properties are exploited to design a meshing algorithm capable of operating in par...

Correct solid/solid classification operations are necessary for fully automatic discretization of solid models. The paper addresses this classification problem in the context of recursive spatial decomposition and domain triangulation. While, in the former case, solid/solid classification must be strictly based on the intersection operation, in the...

An algorithm is presented for constructing a Domain Delaunay triangulation (DDT) of an arbitrarily shaped, multiply-connected (manifold or nonmanifold), planar domain. DDT preserves the boundary of the given region and has properties identical to those of the standard Delaunay triangulation. Construction of this triangulation involves operations (n...

An algorithm is presented for constructing a topologically and geometrically valid Domain Delaunay Tetrahedrization (DDT) of an arbitrarily shaped solid model with quadric curved faces (including objects with holes and nonmanifold objects). The algorithm operates on the boundary representation (B-rep) of the solid, and makes extensive use of proper...

A two-level multigrid algorithm for solving a quadratic finite element models containing tetrahedral meshes is presented. The basic idea is to generate two nested finite element models, first a linear model and then a quadratic one embedded hierarchically into the linear one. The exact solution to the linear model is computed and a two-level iterat...

An algorithm is presented for constructing a topologically and geometrically valid Domain Delaunay Z’etrahedr.zatiorz (DDT) of an arbitrarily shaped solid model with quadric curved faces (including objects with holes and nonmanifold objects). The algorithm operates on the boundary representation (B-rep) of the solid, and makes extensive use of prop...

An element extraction procedure to be used for 3-D automatic meshing in conjunction with Recursive Spatial Decompositions (RSD) is introduced. In this scheme a solid Ω is approximated by a collection of regular cells—either wholly inside the solid or intersecting its boundary—which are then transformed into elements. Element extraction is used to o...

This paper introduces a two-stage algorithm for the automatic conversion of solid models into finite element meshes. In Stage 1 the solid is approximated by a collection of variably sized cells generated by recursive spatial decomposition and stored in a logical tree. In Stage 2 the approximating cell structure, which includes cells that are wholly...

A systematic analysis and evaluation of algorithms for automatic meshing from solid models is attempted. Focusing on algorithms that can be integrated into existing solid-modelling-based CAD systems, only three families of algorithms have been included: element extraction, domain triangulation, and recursive spatial decomposition. Algorithms in the...

The boundary element method and interactive computer graphics together make possible the analysis of general, three-dimensional linear elastic crack propagation. A program called the Fracture Editor has been developed for this purpose. The pre-processing, post-processing and fracture prediction capabilities of this program make up a general purpose...

This paper deals initially with a new algorithm for generating automatically, from solid models of mechanical parts, finite element meshes that are organized as spatially addressable quaternary trees (for 2D work) or octal trees (for 3D work). Because such meshes are inherently hierarchical as well as spatially addressable, they permit efficient su...

Finite element meshes derived automatically from solid models through recursive spatial subdivision schemes (octrees) can be made to inherit the hierarchical structure and the spatial addressability intrinsic to the underlying grid. These two properties, together with the geometric regularity that can also be built into the mesh, make octree based...

Two problems must be solved if the finite element method is to become a reliable and affordable 'blackbox' engineering tool. FE meshes must be generated automatically from CAD databases and mesh analysis must be made self-adaptive. The experimental system described here solves both problems in 2-D through spatial and analytical substructuring techn...

An analysis system for three-dimensional fracture mechanics based on an interactive computer graphic preprocessor and a linear-elastic boundary element code is described. The system is designed for virtual memory mini-computer operations and incorporates a multidomain modeling capability which allows the treatment of domains built up as a sequence...

The trend toward ubiquity of interactive graphics in computational engineering is helping to develop an atmosphere conducive to the combination and unification of various numerical analysis methods. A number of features of interactive computer aided design which foster unification are discussed. Examples are drawn from three principal aspects of co...

Description Twenty papers in this volume are presented in three sections, including stress analysis, test method development, and fracture toughness measurements. One purpose of this volume, given the precracking and other differences in chevron-notched testing compared with existing tests, is to identify conditions that will yield reproducible res...

An interactive computer graphic system has been developed for generating and editing three-dimensional meshes for boundary-integral element analysis. The various difficulties inherent in the generation of solid three-dimensional geometries for both finite and boundary-integral element analysis are examined to explain the advantages of the present a...

An interactive computer graphic system has been developed for generating and editing three-dimensional finite element meshes. The various difficulties inherent to the generation of solid three-dimensional geometries through an effective use of computer graphic techniques are examined to explain the advantages of this system. The method is a combina...