Langan International is a geotechnical consulting firm that has performed Probabilistic Seismic Hazard Analysis (PSHA) for Philippine real estate developer DMCI Homes to help design earthquake-resistant condominiums. PSHA takes into account uncertainties around earthquakes to estimate ground shaking at a site. Langan works with DMCI Homes to develop detailed site-specific ground motion criteria for projects like The Crestmont, Cameron Residences, and The Erin Heights. DMCI Homes then uses these criteria along with building code prescriptions and performance analyses to develop their quake-resistant condo designs.

1. DMCI Homes designs quake-resistant condos
with help from international experts
The Crestmont (Artist’s illustration)
From the home of 2022 NBA Champions Golden State Warriors, Chase Center, to the soon-to-be
world’s tallest tower, Jeddah Tower in the Kingdom of Saudi Arabia, Langan International has built
an impressive portfolio of clients around the world who seek the company’s geotechnical and seismic
expertise.
Founded in 1970, the New Jersey-based firm has earned its reputation as a premier geotechnical
consultant by managing hundreds of projects involving complex, technically challenging sites where
highly specialized site preparation, foundations, and fast-track engineering solutions were required.
The company works closely with developers, property owners, government agencies, corporations,
institutions, and energy companies around the world to engineer cost-effective geotechnical
solutions appropriate for proposed state-of-the-art sports stadiums and arenas, skyscrapers,
infrastructures, airports, colleges and universities, residential and office buildings, hotels, and other
important structures.
Seismic Hazard Analysis
Langan is the same firm that performed Probabilistic Seismic Hazard Analysis (PSHA) for Quadruple
A developer, DMCI Homes, which is an important tool for planning and designing structures in
seismically active regions like the Philippines.
PSHA provides an appropriate quantification of ground shaking hazard at a particular site using the
latest quantification of hazard and seismic standards. The aim of this approach is to provide
structural engineers with criteria for seismic evaluation and design of structures.

2. Langan has served as DMCI Homes’ geotechnical consultant in designing ongoing condominium
projects like The Crestmont, Cameron Residences, The Erin Heights, and upcoming developments
like The Calinea Tower, Kalea Heights, Lyre Garden Residences, Mulberry Place 2, Solmera Coast,
and The Valeron Tower.
DMCI Homes, as builder and developer of its condominium projects, performs civil, structural, and
architectural works in-house with the guidance of local and third-party international consultants like
Langan to develop an earthquake-resistant design.
In designing its condos, DMCI Homes follows the prescriptions of the current building code and
performance-based analyses and testing for thresholds conducted by its consultants on top of
adhering to Philippine Institute of Volcanology and Seismology (Phivolcs) certifications on fault line
distances and National Structural Code of the Philippines (NSCP) guidelines and provisions.
Cameron Residences (Artist’s illustration)
Site-specific estimation of ground-shaking
Ramin Golesorkhi, Langan’s Director of Seismic Engineering Services, said they work with DMCI
Homes to develop detailed site-specific ground motion criteria for seismic design.
“PSHA is about a systematic treatment of uncertainty because earthquakes are uncertain. We don’t
know where it’s going to happen. We don’t know how big these earthquakes are going to be. We
don’t know how often they are going to occur, and also, we don’t know for sure the level of ground
shaking at a particular location,” Golesorkhi said.
“So, because of all of these uncertainties, the PSHA is a way of systematically considering these
uncertainties in order for us to be able to estimate the level of ground-shaking at a particular
location of interest,” explained Golesorkhi.
Rational and up-to-date basis
According to Golesorkhi, since the PSHA is a site-specific estimation of ground shaking, “it provides
a specific, more up-to-date, more appropriate basis, and potentially less conservative values for

3. design than code approach.”
“Site-specific estimation of ground shaking provides a rational and up-to-date basis using the latest
quantification of hazard and latest seismic standards, which means it’s going to be more effective
and more efficient design,” he pointed out.
“These are the kind of information that we (Langan) develop and then they go to the project
structural engineers, who will use them in their structural models to evaluate and design the
structures for these seismic forces,” he continued.
The Erin Heights (Artist’s illustration)
DMCI Homes is the Philippines’ first Quadruple A real estate developer known for building quality
resort-inspired communities in Mega Manila, Baguio, Boracay, and Davao City. The company now
has over 60 properties in its portfolio since it was launched in 1999.
To learn more about DMCI Homes’ pre-selling and ready-for-occupancy projects, units for lease, and
special promos, call (+63) 917-1324585. You may also visit our other social media accounts on
Facebook, Twitter, Instagram, and YouTube.