Local site effects evaluation by surface wave and H/V survey methods in Senirkent(Isparta)region,southwestern Turkey

This study aimed to investigate the site characterization of the Senirkent Basin(Isparta)by using the microtremor(H/V)and surface wave analysis(ReMi)methods.Senirkent district,which is located on the foothill of the Kap?Mountain,are prone to seismic and landslide hazards.After the last landslip disaster(1995),the city has continued to develop on the alluvial basin.The microtremor data collected at 41 stations were analyzed.The predominant frequency and the amplification of the soil were found to be in the range of 1.8–6.6 Hz and 0.8–6.8,respectively.These are 4.0-6.8 Hz and 1-2.5 around the slope of the Kap?Mountain and 0.8-3.6 Hz and 3.0-6.6 at alluvium deposits of the valley.The ReMi data collected along 41 profiles were analyzed to obtain a Vs30 map.The soil classifications were done by using Vs30 values according to NEHRP soil classification criteria.The results showed that the southern area of the study had better soil conditions with Vs30 between 360-1160 m/s and soil class between C and B.The alluvium deposits on the north are relatively low with Vs30 in the range of 260-360 m/s and soil class D.

固溶处理对Mg-4Y-2.5Nd-1.0Gd-0.5Zr合金组织与力学性能的影响

采用显微组织观察、拉伸性能测试、断口形貌观察等方法研究了540℃不同保温时间的固溶处理对Mg-4Y-2.5Nd-1.0Gd-0.5Zr合金组织和力学性能的影响。结果表明:铸态试验合金组织主要由α-Mg基体、短条状的Mg-Y-Nd相及少量颗粒状的Mg_(24)Y_(5)相组成。经540℃×4 h固溶处理的试验合金,晶界处的Mg-Y-Nd相基本溶入基体,晶内Mg_(24)Y_(5)相也明显减少。随着固溶时间再继续延长,第二相无明显变化。随着固溶时间的延长,合金的抗拉强度和伸长率均先升高后降低,经540℃×4 h固溶合金的抗拉强度和伸长率均达到最大值。540℃×4 h为Mg-4Y-2.5Nd-1.0Gd-0.5Zr合金的最佳固溶工艺。