The measurement of the shear wave velocities (V_s) of soils is an important aspect of geotechnical and earthquake engineering, due to its direct relation to the shear modulus (G), which in turn influences the stress–strain behavior of geomaterials. V_s can be directly measured or estimated using a variety of onsite tests or in a laboratory. Methods such as downhole PS logging require boreholes and may not be logistically and economically feasible in all situations. Many researchers have estimated V_s from other geotechnical parameters, such as standard penetration test resistance (SPT-N), by means of empirical correlations. This paper aimed to contribute to this subject by developing an empirical relationship between V_s and SPT-N. Data from twenty sites in Metro Manila were obtained from geotechnical investigation reports. V_s profiles of the same sites were also acquired using the refraction microtremor method. New empirical relationships were developed for all, sandy, and clayey soil types, using a non-linear regression method that is applicable for Metro Manila soils. Statistical evaluation and comparison of the proposed correlations with other previous works suggested the viability of the empirical model.

As an attempt to understand and reflect on the unique circumstances of communities in assessing landslide risk, the Dynaslope Project, under the Department of Science and Technology-Philippine Institute of Volcanology and Seismology (DOST-PHIVOLCS), conducts community landslide risk assessment (CLRA). It is a participatory process of assessing landslide hazards, exposure, vulnerabilities, and capacities of at-risk communities. CLRA includes hazard assessment, participatory community workshops, focus group discussions, and surveys. Risk components are assessed, and results are integrated through a semi-quantitative method that utilizes a scoring system with equivalent categorical labels, i.e., low, moderate, and high, to classify each risk component and the overall landslide risk. It was first conducted in four project sites. Priorities of the communities are taken into account in the assessment by letting them identify and validate the elements-at-risk, vulnerability, and capacity indicators, and the corresponding weights used in the scoring system. The results are presented in household-level risk maps and landslide risk assessment reports. Participatory identification of risk indicators helps in drawing out different community contexts which is useful in developing site-specific risk management strategies and actions.