“我们的地质学家团队, 工程地质学家, 水文地质学家随时准备帮助您满足站点开发的需要. 体育菠菜大平台. 在协助业主方面有广泛和本地化的经验吗, 开发人员, 架构师, 工程师, and governmental agencies in applying value-based geologic engineering and hydrogeologic services to their varied projects.”
美国西部是一个复杂的地质和地震环境, and site development projects located in this region are often faced with challenging conditions. 体育菠菜大平台. understands that these potential issues require the coordinated effort of experienced geologists and hydrogeologists to provide value-oriented solutions. Our team of experienced staff are able to successfully tackle the various geologic hazards and unique groundwater conditions that may affect your property/project including fault rupture hazard investigation, 液化评估, 边坡稳定性问题, 概率和确定性地震风险, 浅层地下水, rippability评估, 矿山复垦, 法医研究, 施工排水, 含水层测试, 及入渗盆设计.
A 地质、地震灾害评估 addresses the hazards inherent to a site as a result of the interaction of site development and the surrounding geologic and seismic environment. The primary hazard posed by earthquakes is the potential for ground rupture to directly affect structures. 地震还经常导致次生灾害，可能造成广泛的破坏. 三种最可能的次生地震灾害是地面震动, 液化/横向传播, 还有山体滑坡或岩崩. 其他地震灾害可能包括非饱和土的地震沉降, 洪水与大坝破坏和洪水有关, 海啸和湖面. 非地震地质灾害包括由收缩/膨胀的土壤构成的灾害, 土壤在湿润时具有很高的坍塌潜力, 局部和区域地面沉降通常是由于地下水的抽取, 以及代表长期定居问题的土壤，如湾泥.
Larger seismic events can produce significant and sometimes catastrophic total and differential settlement of structures as a result of the liquefaction of low-density silty and sandy soils, whereby the soil temporarily loses its strength characteristics due to a pore-water pressure increase caused by the passing seismic waves. Liquefaction effects are generally limited to the upper approximately 50 feet of the soil profile, 还有, 只在饱和或接近饱和的土壤中. 体育菠菜大平台. 一般评估国家指定的液化危险区内的液化潜力, 或者在低密度土壤和浅层地下水共存的地方, 利用空心杆螺旋钻和spt取样产生的地下数据, 或使用锥穿透计测试(CPT)方法. 基于此分析，SALEM工程集团有限公司. can recommend settlement mitigation techniques for structures that may include ground improvement or enhanced foundation design.
按照加州法规的要求, 必须为公立学校进行特定地点的地面震动危害分析, 医院, and essential services buildings if an applicable Seismic Design Category has been established for the site. This analysis determines both probabilistic and deterministic-based ground motions and combines these data to generate a site-specific site response spectra used by structural 工程师 for building design.
The State of California has established Earthquake Fault Zones (formerly known and commonly referred to as an Alquist-Priolo Earthquake Fault Zones [A-P zones]) in many areas of the state along faults it considers as active. State and County governments require that a fault rupture hazard investigation study be conducted for plan approval of any habitable structures proposed to be located within an A-P zone. Subsurface exploration by trenching and trench wall logging is generally required to assess the potential of active faulting within these sites. 挖沟调查可以修改, 或全部取代, using continuous core drilling and logging and/or Cone Pe网rometer Test (CPT) holes where access difficulty makes trenching infeasible. Surface-only (indirect) investigations may include geophysical methods such as seismic refraction or electrical resistivity surveys.
加州的许多地区位于国家指定的滑坡危险区内, which include much of the hilly terrain in Southern California and the Coastal Ranges underlain by relatively young, 薄弱的基础. 计划在这些地区的斜坡趾部及山顶进行发展, 在其他倾斜的地形中也是如此, 是否有可能受到斜坡运动的影响, 事实上, 这种发展可能会对移动潜力产生潜在的负面影响. 体育菠菜大平台. can conduct a stability assessment that includes site reconnaissance and geologic mapping by an Engineering Geologist, 以及土壤/岩石样品的采集和检测. This information is then used to generate geologic maps and cross sections and to conduct slope stability analysis using computer software. 在此基础上，体育菠菜大平台. 可以建议项目修改，包括建筑选址的修改, 深基础, 或边坡改造，包括加固或改建.
许多丘陵地区都曾受到滑坡和斜坡移动的影响. 体育菠菜大平台. can develop slope investigation and monitoring programs to better understand the extent and magnitude of movement. 这些方案可能包括详细的地质绘图, 钻孔及土壤取样, down-hole geologic mapping in large-diameter boreholes to better identify the slide plane upon which movement has occurred, 并安装斜坡运动监测仪器如测斜仪. Compilation and analysis of data generated by the program may then be used to design slope instability mitigation measures that either increase the resisting forces or decrease the driving forces causing slope movement. 这些措施可包括坡度重构, 土壤或岩石支撑, 安装剪切销或回接, 或根据场地限制确定的组合方法, 斜率条件, 和预算.
Many development projects in weathered bedrock terrain will encounter resistant bedrock exposures at or near the surface, 或在计划的分级深度内. 限制项目调度延迟的可能性, it is critical that the equipment adequate to move these materials be available during grading. More importantly, the need to mobilize specialty equipment or use enhanced methods (blasting, etc.)以达到粗略的场地等级，可大幅增加项目的整体预算. 在场地开发规划阶段，SALEM工程集团公司. can provide geophysical services (usually seismic refraction surveys) to determine the seismic velocity profile across a site, which may then be correlated to the capability to rip geologic material using large tracked vehicles equipped with a ripping shank.
体育菠菜大平台. 能否为新的或扩大的砂石开采区域制定资源评估计划. 计划研究可能包括从现有的或附近的操作中获取数据, 地质勘测, 航空照片/卫星图像审查, 地表地球物理方法, and subsurface exploration programs including drilling using sonic or Becker-hammer drilling methods. Former quarry operations often create extensive volumes of non-engineered backfill that may negatively impact the re-use potential of the operation area for building sites due to long-term and differential settlement issues. 体育菠菜大平台. can assist in establishing settlement monitoring and pit reclamation geotechnical criteria that may enable future construction over the former quarry areas with limited restrictions on structural or foundation design.