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 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.

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 guidelines and provisions.

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.